diff options
Diffstat (limited to 'drivers/scsi/atari_NCR5380.c')
| -rw-r--r-- | drivers/scsi/atari_NCR5380.c | 2986 |
1 files changed, 2986 insertions, 0 deletions
diff --git a/drivers/scsi/atari_NCR5380.c b/drivers/scsi/atari_NCR5380.c new file mode 100644 index 00000000000..5d1e78ebed8 --- /dev/null +++ b/drivers/scsi/atari_NCR5380.c @@ -0,0 +1,2986 @@ +/* + * NCR 5380 generic driver routines. These should make it *trivial* + * to implement 5380 SCSI drivers under Linux with a non-trantor + * architecture. + * + * Note that these routines also work with NR53c400 family chips. + * + * Copyright 1993, Drew Eckhardt + * Visionary Computing + * (Unix and Linux consulting and custom programming) + * drew@colorado.edu + * +1 (303) 666-5836 + * + * DISTRIBUTION RELEASE 6. + * + * For more information, please consult + * + * NCR 5380 Family + * SCSI Protocol Controller + * Databook + * + * NCR Microelectronics + * 1635 Aeroplaza Drive + * Colorado Springs, CO 80916 + * 1+ (719) 578-3400 + * 1+ (800) 334-5454 + */ + +/* + * ++roman: To port the 5380 driver to the Atari, I had to do some changes in + * this file, too: + * + * - Some of the debug statements were incorrect (undefined variables and the + * like). I fixed that. + * + * - In information_transfer(), I think a #ifdef was wrong. Looking at the + * possible DMA transfer size should also happen for REAL_DMA. I added this + * in the #if statement. + * + * - When using real DMA, information_transfer() should return in a DATAOUT + * phase after starting the DMA. It has nothing more to do. + * + * - The interrupt service routine should run main after end of DMA, too (not + * only after RESELECTION interrupts). Additionally, it should _not_ test + * for more interrupts after running main, since a DMA process may have + * been started and interrupts are turned on now. The new int could happen + * inside the execution of NCR5380_intr(), leading to recursive + * calls. + * + * - I've added a function merge_contiguous_buffers() that tries to + * merge scatter-gather buffers that are located at contiguous + * physical addresses and can be processed with the same DMA setup. + * Since most scatter-gather operations work on a page (4K) of + * 4 buffers (1K), in more than 90% of all cases three interrupts and + * DMA setup actions are saved. + * + * - I've deleted all the stuff for AUTOPROBE_IRQ, REAL_DMA_POLL, PSEUDO_DMA + * and USLEEP, because these were messing up readability and will never be + * needed for Atari SCSI. + * + * - I've revised the NCR5380_main() calling scheme (relax the 'main_running' + * stuff), and 'main' is executed in a bottom half if awoken by an + * interrupt. + * + * - The code was quite cluttered up by "#if (NDEBUG & NDEBUG_*) printk..." + * constructs. In my eyes, this made the source rather unreadable, so I + * finally replaced that by the *_PRINTK() macros. + * + */ + +/* + * Further development / testing that should be done : + * 1. Test linked command handling code after Eric is ready with + * the high level code. + */ + +#if (NDEBUG & NDEBUG_LISTS) +#define LIST(x,y) \ + { printk("LINE:%d Adding %p to %p\n", __LINE__, (void*)(x), (void*)(y)); \ + if ((x)==(y)) udelay(5); } +#define REMOVE(w,x,y,z) \ + { printk("LINE:%d Removing: %p->%p %p->%p \n", __LINE__, \ + (void*)(w), (void*)(x), (void*)(y), (void*)(z)); \ + if ((x)==(y)) udelay(5); } +#else +#define LIST(x,y) +#define REMOVE(w,x,y,z) +#endif + +#ifndef notyet +#undef LINKED +#endif + +/* + * Design + * Issues : + * + * The other Linux SCSI drivers were written when Linux was Intel PC-only, + * and specifically for each board rather than each chip. This makes their + * adaptation to platforms like the Mac (Some of which use NCR5380's) + * more difficult than it has to be. + * + * Also, many of the SCSI drivers were written before the command queuing + * routines were implemented, meaning their implementations of queued + * commands were hacked on rather than designed in from the start. + * + * When I designed the Linux SCSI drivers I figured that + * while having two different SCSI boards in a system might be useful + * for debugging things, two of the same type wouldn't be used. + * Well, I was wrong and a number of users have mailed me about running + * multiple high-performance SCSI boards in a server. + * + * Finally, when I get questions from users, I have no idea what + * revision of my driver they are running. + * + * This driver attempts to address these problems : + * This is a generic 5380 driver. To use it on a different platform, + * one simply writes appropriate system specific macros (ie, data + * transfer - some PC's will use the I/O bus, 68K's must use + * memory mapped) and drops this file in their 'C' wrapper. + * + * As far as command queueing, two queues are maintained for + * each 5380 in the system - commands that haven't been issued yet, + * and commands that are currently executing. This means that an + * unlimited number of commands may be queued, letting + * more commands propagate from the higher driver levels giving higher + * throughput. Note that both I_T_L and I_T_L_Q nexuses are supported, + * allowing multiple commands to propagate all the way to a SCSI-II device + * while a command is already executing. + * + * To solve the multiple-boards-in-the-same-system problem, + * there is a separate instance structure for each instance + * of a 5380 in the system. So, multiple NCR5380 drivers will + * be able to coexist with appropriate changes to the high level + * SCSI code. + * + * A NCR5380_PUBLIC_REVISION macro is provided, with the release + * number (updated for each public release) printed by the + * NCR5380_print_options command, which should be called from the + * wrapper detect function, so that I know what release of the driver + * users are using. + * + * Issues specific to the NCR5380 : + * + * When used in a PIO or pseudo-dma mode, the NCR5380 is a braindead + * piece of hardware that requires you to sit in a loop polling for + * the REQ signal as long as you are connected. Some devices are + * brain dead (ie, many TEXEL CD ROM drives) and won't disconnect + * while doing long seek operations. + * + * The workaround for this is to keep track of devices that have + * disconnected. If the device hasn't disconnected, for commands that + * should disconnect, we do something like + * + * while (!REQ is asserted) { sleep for N usecs; poll for M usecs } + * + * Some tweaking of N and M needs to be done. An algorithm based + * on "time to data" would give the best results as long as short time + * to datas (ie, on the same track) were considered, however these + * broken devices are the exception rather than the rule and I'd rather + * spend my time optimizing for the normal case. + * + * Architecture : + * + * At the heart of the design is a coroutine, NCR5380_main, + * which is started when not running by the interrupt handler, + * timer, and queue command function. It attempts to establish + * I_T_L or I_T_L_Q nexuses by removing the commands from the + * issue queue and calling NCR5380_select() if a nexus + * is not established. + * + * Once a nexus is established, the NCR5380_information_transfer() + * phase goes through the various phases as instructed by the target. + * if the target goes into MSG IN and sends a DISCONNECT message, + * the command structure is placed into the per instance disconnected + * queue, and NCR5380_main tries to find more work. If USLEEP + * was defined, and the target is idle for too long, the system + * will try to sleep. + * + * If a command has disconnected, eventually an interrupt will trigger, + * calling NCR5380_intr() which will in turn call NCR5380_reselect + * to reestablish a nexus. This will run main if necessary. + * + * On command termination, the done function will be called as + * appropriate. + * + * SCSI pointers are maintained in the SCp field of SCSI command + * structures, being initialized after the command is connected + * in NCR5380_select, and set as appropriate in NCR5380_information_transfer. + * Note that in violation of the standard, an implicit SAVE POINTERS operation + * is done, since some BROKEN disks fail to issue an explicit SAVE POINTERS. + */ + +/* + * Using this file : + * This file a skeleton Linux SCSI driver for the NCR 5380 series + * of chips. To use it, you write an architecture specific functions + * and macros and include this file in your driver. + * + * These macros control options : + * AUTOSENSE - if defined, REQUEST SENSE will be performed automatically + * for commands that return with a CHECK CONDITION status. + * + * LINKED - if defined, linked commands are supported. + * + * REAL_DMA - if defined, REAL DMA is used during the data transfer phases. + * + * SUPPORT_TAGS - if defined, SCSI-2 tagged queuing is used where possible + * + * These macros MUST be defined : + * + * NCR5380_read(register) - read from the specified register + * + * NCR5380_write(register, value) - write to the specific register + * + * Either real DMA *or* pseudo DMA may be implemented + * REAL functions : + * NCR5380_REAL_DMA should be defined if real DMA is to be used. + * Note that the DMA setup functions should return the number of bytes + * that they were able to program the controller for. + * + * Also note that generic i386/PC versions of these macros are + * available as NCR5380_i386_dma_write_setup, + * NCR5380_i386_dma_read_setup, and NCR5380_i386_dma_residual. + * + * NCR5380_dma_write_setup(instance, src, count) - initialize + * NCR5380_dma_read_setup(instance, dst, count) - initialize + * NCR5380_dma_residual(instance); - residual count + * + * PSEUDO functions : + * NCR5380_pwrite(instance, src, count) + * NCR5380_pread(instance, dst, count); + * + * If nothing specific to this implementation needs doing (ie, with external + * hardware), you must also define + * + * NCR5380_queue_command + * NCR5380_reset + * NCR5380_abort + * NCR5380_proc_info + * + * to be the global entry points into the specific driver, ie + * #define NCR5380_queue_command t128_queue_command. + * + * If this is not done, the routines will be defined as static functions + * with the NCR5380* names and the user must provide a globally + * accessible wrapper function. + * + * The generic driver is initialized by calling NCR5380_init(instance), + * after setting the appropriate host specific fields and ID. If the + * driver wishes to autoprobe for an IRQ line, the NCR5380_probe_irq(instance, + * possible) function may be used. Before the specific driver initialization + * code finishes, NCR5380_print_options should be called. + */ + +static struct Scsi_Host *first_instance = NULL; +static Scsi_Host_Template *the_template = NULL; + +/* Macros ease life... :-) */ +#define SETUP_HOSTDATA(in) \ + struct NCR5380_hostdata *hostdata = \ + (struct NCR5380_hostdata *)(in)->hostdata +#define HOSTDATA(in) ((struct NCR5380_hostdata *)(in)->hostdata) + +#define NEXT(cmd) ((Scsi_Cmnd *)((cmd)->host_scribble)) +#define NEXTADDR(cmd) ((Scsi_Cmnd **)&((cmd)->host_scribble)) + +#define HOSTNO instance->host_no +#define H_NO(cmd) (cmd)->device->host->host_no + +#ifdef SUPPORT_TAGS + +/* + * Functions for handling tagged queuing + * ===================================== + * + * ++roman (01/96): Now I've implemented SCSI-2 tagged queuing. Some notes: + * + * Using consecutive numbers for the tags is no good idea in my eyes. There + * could be wrong re-usings if the counter (8 bit!) wraps and some early + * command has been preempted for a long time. My solution: a bitfield for + * remembering used tags. + * + * There's also the problem that each target has a certain queue size, but we + * cannot know it in advance :-( We just see a QUEUE_FULL status being + * returned. So, in this case, the driver internal queue size assumption is + * reduced to the number of active tags if QUEUE_FULL is returned by the + * target. The command is returned to the mid-level, but with status changed + * to BUSY, since --as I've seen-- the mid-level can't handle QUEUE_FULL + * correctly. + * + * We're also not allowed running tagged commands as long as an untagged + * command is active. And REQUEST SENSE commands after a contingent allegiance + * condition _must_ be untagged. To keep track whether an untagged command has + * been issued, the host->busy array is still employed, as it is without + * support for tagged queuing. + * + * One could suspect that there are possible race conditions between + * is_lun_busy(), cmd_get_tag() and cmd_free_tag(). But I think this isn't the + * case: is_lun_busy() and cmd_get_tag() are both called from NCR5380_main(), + * which already guaranteed to be running at most once. It is also the only + * place where tags/LUNs are allocated. So no other allocation can slip + * between that pair, there could only happen a reselection, which can free a + * tag, but that doesn't hurt. Only the sequence in cmd_free_tag() becomes + * important: the tag bit must be cleared before 'nr_allocated' is decreased. + */ + +/* -1 for TAG_NONE is not possible with unsigned char cmd->tag */ +#undef TAG_NONE +#define TAG_NONE 0xff + +typedef struct { + DECLARE_BITMAP(allocated, MAX_TAGS); + int nr_allocated; + int queue_size; +} TAG_ALLOC; + +static TAG_ALLOC TagAlloc[8][8]; /* 8 targets and 8 LUNs */ + + +static void __init init_tags( void ) +{ + int target, lun; + TAG_ALLOC *ta; + + if (!setup_use_tagged_queuing) + return; + + for( target = 0; target < 8; ++target ) { + for( lun = 0; lun < 8; ++lun ) { + ta = &TagAlloc[target][lun]; + bitmap_zero(ta->allocated, MAX_TAGS); + ta->nr_allocated = 0; + /* At the beginning, assume the maximum queue size we could + * support (MAX_TAGS). This value will be decreased if the target + * returns QUEUE_FULL status. + */ + ta->queue_size = MAX_TAGS; + } + } +} + + +/* Check if we can issue a command to this LUN: First see if the LUN is marked + * busy by an untagged command. If the command should use tagged queuing, also + * check that there is a free tag and the target's queue won't overflow. This + * function should be called with interrupts disabled to avoid race + * conditions. + */ + +static int is_lun_busy( Scsi_Cmnd *cmd, int should_be_tagged ) +{ + SETUP_HOSTDATA(cmd->device->host); + + if (hostdata->busy[cmd->device->id] & (1 << cmd->device->lun)) + return( 1 ); + if (!should_be_tagged || + !setup_use_tagged_queuing || !cmd->device->tagged_supported) + return( 0 ); + if (TagAlloc[cmd->device->id][cmd->device->lun].nr_allocated >= + TagAlloc[cmd->device->id][cmd->device->lun].queue_size ) { + TAG_PRINTK( "scsi%d: target %d lun %d: no free tags\n", + H_NO(cmd), cmd->device->id, cmd->device->lun ); + return( 1 ); + } + return( 0 ); +} + + +/* Allocate a tag for a command (there are no checks anymore, check_lun_busy() + * must be called before!), or reserve the LUN in 'busy' if the command is + * untagged. + */ + +static void cmd_get_tag( Scsi_Cmnd *cmd, int should_be_tagged ) +{ + SETUP_HOSTDATA(cmd->device->host); + + /* If we or the target don't support tagged queuing, allocate the LUN for + * an untagged command. + */ + if (!should_be_tagged || + !setup_use_tagged_queuing || !cmd->device->tagged_supported) { + cmd->tag = TAG_NONE; + hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); + TAG_PRINTK( "scsi%d: target %d lun %d now allocated by untagged " + "command\n", H_NO(cmd), cmd->device->id, cmd->device->lun ); + } + else { + TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun]; + + cmd->tag = find_first_zero_bit( ta->allocated, MAX_TAGS ); + set_bit( cmd->tag, ta->allocated ); + ta->nr_allocated++; + TAG_PRINTK( "scsi%d: using tag %d for target %d lun %d " + "(now %d tags in use)\n", + H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun, + ta->nr_allocated ); + } +} + + +/* Mark the tag of command 'cmd' as free, or in case of an untagged command, + * unlock the LUN. + */ + +static void cmd_free_tag( Scsi_Cmnd *cmd ) +{ + SETUP_HOSTDATA(cmd->device->host); + + if (cmd->tag == TAG_NONE) { + hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); + TAG_PRINTK( "scsi%d: target %d lun %d untagged cmd finished\n", + H_NO(cmd), cmd->device->id, cmd->device->lun ); + } + else if (cmd->tag >= MAX_TAGS) { + printk(KERN_NOTICE "scsi%d: trying to free bad tag %d!\n", + H_NO(cmd), cmd->tag ); + } + else { + TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun]; + clear_bit( cmd->tag, ta->allocated ); + ta->nr_allocated--; + TAG_PRINTK( "scsi%d: freed tag %d for target %d lun %d\n", + H_NO(cmd), cmd->tag, cmd->device->id, cmd->device->lun ); + } +} + + +static void free_all_tags( void ) +{ + int target, lun; + TAG_ALLOC *ta; + + if (!setup_use_tagged_queuing) + return; + + for( target = 0; target < 8; ++target ) { + for( lun = 0; lun < 8; ++lun ) { + ta = &TagAlloc[target][lun]; + bitmap_zero(ta->allocated, MAX_TAGS); + ta->nr_allocated = 0; + } + } +} + +#endif /* SUPPORT_TAGS */ + + +/* + * Function: void merge_contiguous_buffers( Scsi_Cmnd *cmd ) + * + * Purpose: Try to merge several scatter-gather requests into one DMA + * transfer. This is possible if the scatter buffers lie on + * physical contiguous addresses. + * + * Parameters: Scsi_Cmnd *cmd + * The command to work on. The first scatter buffer's data are + * assumed to be already transfered into ptr/this_residual. + */ + +static void merge_contiguous_buffers( Scsi_Cmnd *cmd ) +{ + unsigned long endaddr; +#if (NDEBUG & NDEBUG_MERGING) + unsigned long oldlen = cmd->SCp.this_residual; + int cnt = 1; +#endif + + for (endaddr = virt_to_phys(cmd->SCp.ptr + cmd->SCp.this_residual - 1) + 1; + cmd->SCp.buffers_residual && + virt_to_phys(page_address(cmd->SCp.buffer[1].page)+ + cmd->SCp.buffer[1].offset) == endaddr; ) { + MER_PRINTK("VTOP(%p) == %08lx -> merging\n", + cmd->SCp.buffer[1].address, endaddr); +#if (NDEBUG & NDEBUG_MERGING) + ++cnt; +#endif + ++cmd->SCp.buffer; + --cmd->SCp.buffers_residual; + cmd->SCp.this_residual += cmd->SCp.buffer->length; + endaddr += cmd->SCp.buffer->length; + } +#if (NDEBUG & NDEBUG_MERGING) + if (oldlen != cmd->SCp.this_residual) + MER_PRINTK("merged %d buffers from %p, new length %08x\n", + cnt, cmd->SCp.ptr, cmd->SCp.this_residual); +#endif +} + +/* + * Function : void initialize_SCp(Scsi_Cmnd *cmd) + * + * Purpose : initialize the saved data pointers for cmd to point to the + * start of the buffer. + * + * Inputs : cmd - Scsi_Cmnd structure to have pointers reset. + */ + +static __inline__ void initialize_SCp(Scsi_Cmnd *cmd) +{ + /* + * Initialize the Scsi Pointer field so that all of the commands in the + * various queues are valid. + */ + + if (cmd->use_sg) { + cmd->SCp.buffer = (struct scatterlist *) cmd->buffer; + cmd->SCp.buffers_residual = cmd->use_sg - 1; + cmd->SCp.ptr = (char *)page_address(cmd->SCp.buffer->page)+ + cmd->SCp.buffer->offset; + cmd->SCp.this_residual = cmd->SCp.buffer->length; + /* ++roman: Try to merge some scatter-buffers if they are at + * contiguous physical addresses. + */ + merge_contiguous_buffers( cmd ); + } else { + cmd->SCp.buffer = NULL; + cmd->SCp.buffers_residual = 0; + cmd->SCp.ptr = (char *) cmd->request_buffer; + cmd->SCp.this_residual = cmd->request_bufflen; + } +} + +#include <linux/config.h> +#include <linux/delay.h> + +#if NDEBUG +static struct { + unsigned char mask; + const char * name;} +signals[] = {{ SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" }, + { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD, "CD" }, { SR_IO, "IO" }, + { SR_SEL, "SEL" }, {0, NULL}}, +basrs[] = {{BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}}, +icrs[] = {{ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"}, + {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"}, + {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"}, + {0, NULL}}, +mrs[] = {{MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"}, + {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR, + "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"}, + {MR_MONITOR_BSY, "MODE MONITOR BSY"}, + {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"}, + {0, NULL}}; + +/* + * Function : void NCR5380_print(struct Scsi_Host *instance) + * + * Purpose : print the SCSI bus signals for debugging purposes + * + * Input : instance - which NCR5380 + */ + +static void NCR5380_print(struct Scsi_Host *instance) { + unsigned char status, data, basr, mr, icr, i; + unsigned long flags; + + local_irq_save(flags); + data = NCR5380_read(CURRENT_SCSI_DATA_REG); + status = NCR5380_read(STATUS_REG); + mr = NCR5380_read(MODE_REG); + icr = NCR5380_read(INITIATOR_COMMAND_REG); + basr = NCR5380_read(BUS_AND_STATUS_REG); + local_irq_restore(flags); + printk("STATUS_REG: %02x ", status); + for (i = 0; signals[i].mask ; ++i) + if (status & signals[i].mask) + printk(",%s", signals[i].name); + printk("\nBASR: %02x ", basr); + for (i = 0; basrs[i].mask ; ++i) + if (basr & basrs[i].mask) + printk(",%s", basrs[i].name); + printk("\nICR: %02x ", icr); + for (i = 0; icrs[i].mask; ++i) + if (icr & icrs[i].mask) + printk(",%s", icrs[i].name); + printk("\nMODE: %02x ", mr); + for (i = 0; mrs[i].mask; ++i) + if (mr & mrs[i].mask) + printk(",%s", mrs[i].name); + printk("\n"); +} + +static struct { + unsigned char value; + const char *name; +} phases[] = { + {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"}, + {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"}, + {PHASE_UNKNOWN, "UNKNOWN"}}; + +/* + * Function : void NCR5380_print_phase(struct Scsi_Host *instance) + * + * Purpose : print the current SCSI phase for debugging purposes + * + * Input : instance - which NCR5380 + */ + +static void NCR5380_print_phase(struct Scsi_Host *instance) +{ + unsigned char status; + int i; + + status = NCR5380_read(STATUS_REG); + if (!(status & SR_REQ)) + printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO); + else { + for (i = 0; (phases[i].value != PHASE_UNKNOWN) && + (phases[i].value != (status & PHASE_MASK)); ++i); + printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name); + } +} + +#else /* !NDEBUG */ + +/* dummies... */ +__inline__ void NCR5380_print(struct Scsi_Host *instance) { }; +__inline__ void NCR5380_print_phase(struct Scsi_Host *instance) { }; + +#endif + +/* + * ++roman: New scheme of calling NCR5380_main() + * + * If we're not in an interrupt, we can call our main directly, it cannot be + * already running. Else, we queue it on a task queue, if not 'main_running' + * tells us that a lower level is already executing it. This way, + * 'main_running' needs not be protected in a special way. + * + * queue_main() is a utility function for putting our main onto the task + * queue, if main_running is false. It should be called only from a + * interrupt or bottom half. + */ + +#include <linux/workqueue.h> +#include <linux/interrupt.h> + +static volatile int main_running = 0; +static DECLARE_WORK(NCR5380_tqueue, (void (*)(void*))NCR5380_main, NULL); + +static __inline__ void queue_main(void) +{ + if (!main_running) { + /* If in interrupt and NCR5380_main() not already running, + queue it on the 'immediate' task queue, to be processed + immediately after the current interrupt processing has + finished. */ + schedule_work(&NCR5380_tqueue); + } + /* else: nothing to do: the running NCR5380_main() will pick up + any newly queued command. */ +} + + +static inline void NCR5380_all_init (void) +{ + static int done = 0; + if (!done) { + INI_PRINTK("scsi : NCR5380_all_init()\n"); + done = 1; + } +} + + +/* + * Function : void NCR58380_print_options (struct Scsi_Host *instance) + * + * Purpose : called by probe code indicating the NCR5380 driver + * options that were selected. + * + * Inputs : instance, pointer to this instance. Unused. + */ + +static void __init NCR5380_print_options (struct Scsi_Host *instance) +{ + printk(" generic options" +#ifdef AUTOSENSE + " AUTOSENSE" +#endif +#ifdef REAL_DMA + " REAL DMA" +#endif +#ifdef PARITY + " PARITY" +#endif +#ifdef SUPPORT_TAGS + " SCSI-2 TAGGED QUEUING" +#endif + ); + printk(" generic release=%d", NCR5380_PUBLIC_RELEASE); +} + +/* + * Function : void NCR5380_print_status (struct Scsi_Host *instance) + * + * Purpose : print commands in the various queues, called from + * NCR5380_abort and NCR5380_debug to aid debugging. + * + * Inputs : instance, pointer to this instance. + */ + +static void NCR5380_print_status (struct Scsi_Host *instance) +{ + char *pr_bfr; + char *start; + int len; + + NCR_PRINT(NDEBUG_ANY); + NCR_PRINT_PHASE(NDEBUG_ANY); + + pr_bfr = (char *) __get_free_page(GFP_ATOMIC); + if (!pr_bfr) { + printk("NCR5380_print_status: no memory for print buffer\n"); + return; + } + len = NCR5380_proc_info(pr_bfr, &start, 0, PAGE_SIZE, HOSTNO, 0); + pr_bfr[len] = 0; + printk("\n%s\n", pr_bfr); + free_page((unsigned long) pr_bfr); +} + + +/******************************************/ +/* + * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED] + * + * *buffer: I/O buffer + * **start: if inout == FALSE pointer into buffer where user read should start + * offset: current offset + * length: length of buffer + * hostno: Scsi_Host host_no + * inout: TRUE - user is writing; FALSE - user is reading + * + * Return the number of bytes read from or written +*/ + +#undef SPRINTF +#define SPRINTF(fmt,args...) \ + do { if (pos + strlen(fmt) + 20 /* slop */ < buffer + length) \ + pos += sprintf(pos, fmt , ## args); } while(0) +static +char *lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length); + +static +int NCR5380_proc_info (struct Scsi_Host *instance, char *buffer, char **start, off_t offset, + int length, int inout) +{ + char *pos = buffer; + struct NCR5380_hostdata *hostdata; + Scsi_Cmnd *ptr; + unsigned long flags; + off_t begin = 0; +#define check_offset() \ + do { \ + if (pos - buffer < offset - begin) { \ + begin += pos - buffer; \ + pos = buffer; \ + } \ + } while (0) + + hostdata = (struct NCR5380_hostdata *)instance->hostdata; + + if (inout) { /* Has data been written to the file ? */ + return(-ENOSYS); /* Currently this is a no-op */ + } + SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE); + check_offset(); + local_irq_save(flags); + SPRINTF("NCR5380: coroutine is%s running.\n", main_running ? "" : "n't"); + check_offset(); + if (!hostdata->connected) + SPRINTF("scsi%d: no currently connected command\n", HOSTNO); + else + pos = lprint_Scsi_Cmnd ((Scsi_Cmnd *) hostdata->connected, + pos, buffer, length); + SPRINTF("scsi%d: issue_queue\n", HOSTNO); + check_offset(); + for (ptr = (Scsi_Cmnd *) hostdata->issue_queue; ptr; ptr = NEXT(ptr)) { + pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length); + check_offset(); + } + + SPRINTF("scsi%d: disconnected_queue\n", HOSTNO); + check_offset(); + for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr; + ptr = NEXT(ptr)) { + pos = lprint_Scsi_Cmnd (ptr, pos, buffer, length); + check_offset(); + } + + local_irq_restore(flags); + *start = buffer + (offset - begin); + if (pos - buffer < offset - begin) + return 0; + else if (pos - buffer - (offset - begin) < length) + return pos - buffer - (offset - begin); + return length; +} + +static char * +lprint_Scsi_Cmnd (Scsi_Cmnd *cmd, char *pos, char *buffer, int length) +{ + int i, s; + unsigned char *command; + SPRINTF("scsi%d: destination target %d, lun %d\n", + H_NO(cmd), cmd->device->id, cmd->device->lun); + SPRINTF(" command = "); + command = cmd->cmnd; + SPRINTF("%2d (0x%02x)", command[0], command[0]); + for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i) + SPRINTF(" %02x", command[i]); + SPRINTF("\n"); + return pos; +} + + +/* + * Function : void NCR5380_init (struct Scsi_Host *instance) + * + * Purpose : initializes *instance and corresponding 5380 chip. + * + * Inputs : instance - instantiation of the 5380 driver. + * + * Notes : I assume that the host, hostno, and id bits have been + * set correctly. I don't care about the irq and other fields. + * + */ + +static int NCR5380_init (struct Scsi_Host *instance, int flags) +{ + int i; + SETUP_HOSTDATA(instance); + + NCR5380_all_init(); + + hostdata->aborted = 0; + hostdata->id_mask = 1 << instance->this_id; + hostdata->id_higher_mask = 0; + for (i = hostdata->id_mask; i <= 0x80; i <<= 1) + if (i > hostdata->id_mask) + hostdata->id_higher_mask |= i; + for (i = 0; i < 8; ++i) + hostdata->busy[i] = 0; +#ifdef SUPPORT_TAGS + init_tags(); +#endif +#if defined (REAL_DMA) + hostdata->dma_len = 0; +#endif + hostdata->targets_present = 0; + hostdata->connected = NULL; + hostdata->issue_queue = NULL; + hostdata->disconnected_queue = NULL; + hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT; + + if (!the_template) { + the_template = instance->hostt; + first_instance = instance; + } + + +#ifndef AUTOSENSE + if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1)) + printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n" + " without AUTOSENSE option, contingent allegiance conditions may\n" + " be incorrectly cleared.\n", HOSTNO); +#endif /* def AUTOSENSE */ + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(TARGET_COMMAND_REG, 0); + NCR5380_write(SELECT_ENABLE_REG, 0); + + return 0; +} + +/* + * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd, + * void (*done)(Scsi_Cmnd *)) + * + * Purpose : enqueues a SCSI command + * + * Inputs : cmd - SCSI command, done - function called on completion, with + * a pointer to the command descriptor. + * + * Returns : 0 + * + * Side effects : + * cmd is added to the per instance issue_queue, with minor + * twiddling done to the host specific fields of cmd. If the + * main coroutine is not running, it is restarted. + * + */ + +static +int NCR5380_queue_command (Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *)) +{ + SETUP_HOSTDATA(cmd->device->host); + Scsi_Cmnd *tmp; + int oldto; + unsigned long flags; + extern int update_timeout(Scsi_Cmnd * SCset, int timeout); + +#if (NDEBUG & NDEBUG_NO_WRITE) + switch (cmd->cmnd[0]) { + case WRITE_6: + case WRITE_10: + printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n", + H_NO(cmd)); + cmd->result = (DID_ERROR << 16); + done(cmd); + return 0; + } +#endif /* (NDEBUG & NDEBUG_NO_WRITE) */ + + +#ifdef NCR5380_STATS +# if 0 + if (!hostdata->connected && !hostdata->issue_queue && + !hostdata->disconnected_queue) { + hostdata->timebase = jiffies; + } +# endif +# ifdef NCR5380_STAT_LIMIT + if (cmd->request_bufflen > NCR5380_STAT_LIMIT) +# endif + switch (cmd->cmnd[0]) + { + case WRITE: + case WRITE_6: + case WRITE_10: + hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase); + hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen; + hostdata->pendingw++; + break; + case READ: + case READ_6: + case READ_10: + hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase); + hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen; + hostdata->pendingr++; + break; + } +#endif + + /* + * We use the host_scribble field as a pointer to the next command + * in a queue + */ + + NEXT(cmd) = NULL; + cmd->scsi_done = done; + + cmd->result = 0; + + + /* + * Insert the cmd into the issue queue. Note that REQUEST SENSE + * commands are added to the head of the queue since any command will + * clear the contingent allegiance condition that exists and the + * sense data is only guaranteed to be valid while the condition exists. + */ + + local_irq_save(flags); + /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA. + * Otherwise a running NCR5380_main may steal the lock. + * Lock before actually inserting due to fairness reasons explained in + * atari_scsi.c. If we insert first, then it's impossible for this driver + * to release the lock. + * Stop timer for this command while waiting for the lock, or timeouts + * may happen (and they really do), and it's no good if the command doesn't + * appear in any of the queues. + * ++roman: Just disabling the NCR interrupt isn't sufficient here, + * because also a timer int can trigger an abort or reset, which would + * alter queues and touch the lock. + */ + if (!IS_A_TT()) { + oldto = update_timeout(cmd, 0); + falcon_get_lock(); + update_timeout(cmd, oldto); + } + if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) { + LIST(cmd, hostdata->issue_queue); + NEXT(cmd) = hostdata->issue_queue; + hostdata->issue_queue = cmd; + } else { + for (tmp = (Scsi_Cmnd *)hostdata->issue_queue; + NEXT(tmp); tmp = NEXT(tmp)) + ; + LIST(cmd, tmp); + NEXT(tmp) = cmd; + } + local_irq_restore(flags); + + QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd), + (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail"); + + /* If queue_command() is called from an interrupt (real one or bottom + * half), we let queue_main() do the job of taking care about main. If it + * is already running, this is a no-op, else main will be queued. + * + * If we're not in an interrupt, we can call NCR5380_main() + * unconditionally, because it cannot be already running. + */ + if (in_interrupt() || ((flags >> 8) & 7) >= 6) + queue_main(); + else + NCR5380_main(NULL); + return 0; +} + +/* + * Function : NCR5380_main (void) + * + * Purpose : NCR5380_main is a coroutine that runs as long as more work can + * be done on the NCR5380 host adapters in a system. Both + * NCR5380_queue_command() and NCR5380_intr() will try to start it + * in case it is not running. + * + * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should + * reenable them. This prevents reentrancy and kernel stack overflow. + */ + +static void NCR5380_main (void *bl) +{ + Scsi_Cmnd *tmp, *prev; + struct Scsi_Host *instance = first_instance; + struct NCR5380_hostdata *hostdata = HOSTDATA(instance); + int done; + unsigned long flags; + + /* + * We run (with interrupts disabled) until we're sure that none of + * the host adapters have anything that can be done, at which point + * we set main_running to 0 and exit. + * + * Interrupts are enabled before doing various other internal + * instructions, after we've decided that we need to run through + * the loop again. + * + * this should prevent any race conditions. + * + * ++roman: Just disabling the NCR interrupt isn't sufficient here, + * because also a timer int can trigger an abort or reset, which can + * alter queues and touch the Falcon lock. + */ + + /* Tell int handlers main() is now already executing. Note that + no races are possible here. If an int comes in before + 'main_running' is set here, and queues/executes main via the + task queue, it doesn't do any harm, just this instance of main + won't find any work left to do. */ + if (main_running) + return; + main_running = 1; + + local_save_flags(flags); + do { + local_irq_disable(); /* Freeze request queues */ + done = 1; + + if (!hostdata->connected) { + MAIN_PRINTK( "scsi%d: not connected\n", HOSTNO ); + /* + * Search through the issue_queue for a command destined + * for a target that's not busy. + */ +#if (NDEBUG & NDEBUG_LISTS) + for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL; + tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp)) + ; + /*printk("%p ", tmp);*/ + if ((tmp == prev) && tmp) printk(" LOOP\n");/* else printk("\n");*/ +#endif + for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, + prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp) ) { + +#if (NDEBUG & NDEBUG_LISTS) + if (prev != tmp) + printk("MAIN tmp=%p target=%d busy=%d lun=%d\n", + tmp, tmp->device->id, hostdata->busy[tmp->device->id], + tmp->device->lun); +#endif + /* When we find one, remove it from the issue queue. */ + /* ++guenther: possible race with Falcon locking */ + if ( +#ifdef SUPPORT_TAGS + !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE) +#else + !(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun)) +#endif + ) { + /* ++guenther: just to be sure, this must be atomic */ + local_irq_disable(); + if (prev) { + REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); + NEXT(prev) = NEXT(tmp); + } else { + REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp)); + hostdata->issue_queue = NEXT(tmp); + } + NEXT(tmp) = NULL; + falcon_dont_release++; + + /* reenable interrupts after finding one */ + local_irq_restore(flags); + + /* + * Attempt to establish an I_T_L nexus here. + * On success, instance->hostdata->connected is set. + * On failure, we must add the command back to the + * issue queue so we can keep trying. + */ + MAIN_PRINTK("scsi%d: main(): command for target %d " + "lun %d removed from issue_queue\n", + HOSTNO, tmp->device->id, tmp->device->lun); + /* + * REQUEST SENSE commands are issued without tagged + * queueing, even on SCSI-II devices because the + * contingent allegiance condition exists for the + * entire unit. + */ + /* ++roman: ...and the standard also requires that + * REQUEST SENSE command are untagged. + */ + +#ifdef SUPPORT_TAGS + cmd_get_tag( tmp, tmp->cmnd[0] != REQUEST_SENSE ); +#endif + if (!NCR5380_select(instance, tmp, + (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE : + TAG_NEXT)) { + falcon_dont_release--; + /* release if target did not response! */ + falcon_release_lock_if_possible( hostdata ); + break; + } else { + local_irq_disable(); + LIST(tmp, hostdata->issue_queue); + NEXT(tmp) = hostdata->issue_queue; + hostdata->issue_queue = tmp; +#ifdef SUPPORT_TAGS + cmd_free_tag( tmp ); +#endif + falcon_dont_release--; + local_irq_restore(flags); + MAIN_PRINTK("scsi%d: main(): select() failed, " + "returned to issue_queue\n", HOSTNO); + if (hostdata->connected) + break; + } + } /* if target/lun/target queue is not busy */ + } /* for issue_queue */ + } /* if (!hostdata->connected) */ + + if (hostdata->connected +#ifdef REAL_DMA + && !hostdata->dma_len +#endif + ) { + local_irq_restore(flags); + MAIN_PRINTK("scsi%d: main: performing information transfer\n", + HOSTNO); + NCR5380_information_transfer(instance); + MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO); + done = 0; + } + } while (!done); + + /* Better allow ints _after_ 'main_running' has been cleared, else + an interrupt could believe we'll pick up the work it left for + us, but we won't see it anymore here... */ + main_running = 0; + local_irq_restore(flags); +} + + +#ifdef REAL_DMA +/* + * Function : void NCR5380_dma_complete (struct Scsi_Host *instance) + * + * Purpose : Called by interrupt handler when DMA finishes or a phase + * mismatch occurs (which would finish the DMA transfer). + * + * Inputs : instance - this instance of the NCR5380. + * + */ + +static void NCR5380_dma_complete( struct Scsi_Host *instance ) +{ + SETUP_HOSTDATA(instance); + int transfered, saved_data = 0, overrun = 0, cnt, toPIO; + unsigned char **data, p; + volatile int *count; + + if (!hostdata->connected) { + printk(KERN_WARNING "scsi%d: received end of DMA interrupt with " + "no connected cmd\n", HOSTNO); + return; + } + + if (atari_read_overruns) { + p = hostdata->connected->SCp.phase; + if (p & SR_IO) { + udelay(10); + if ((((NCR5380_read(BUS_AND_STATUS_REG)) & + (BASR_PHASE_MATCH|BASR_ACK)) == + (BASR_PHASE_MATCH|BASR_ACK))) { + saved_data = NCR5380_read(INPUT_DATA_REG); + overrun = 1; + DMA_PRINTK("scsi%d: read overrun handled\n", HOSTNO); + } + } + } + + DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n", + HOSTNO, NCR5380_read(BUS_AND_STATUS_REG), + NCR5380_read(STATUS_REG)); + + (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + + transfered = hostdata->dma_len - NCR5380_dma_residual(instance); + hostdata->dma_len = 0; + + data = (unsigned char **) &(hostdata->connected->SCp.ptr); + count = &(hostdata->connected->SCp.this_residual); + *data += transfered; + *count -= transfered; + + if (atari_read_overruns) { + if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) { + cnt = toPIO = atari_read_overruns; + if (overrun) { + DMA_PRINTK("Got an input overrun, using saved byte\n"); + *(*data)++ = saved_data; + (*count)--; + cnt--; + toPIO--; + } + DMA_PRINTK("Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data); + NCR5380_transfer_pio(instance, &p, &cnt, data); + *count -= toPIO - cnt; + } + } +} +#endif /* REAL_DMA */ + + +/* + * Function : void NCR5380_intr (int irq) + * + * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses + * from the disconnected queue, and restarting NCR5380_main() + * as required. + * + * Inputs : int irq, irq that caused this interrupt. + * + */ + +static irqreturn_t NCR5380_intr (int irq, void *dev_id, struct pt_regs *regs) +{ + struct Scsi_Host *instance = first_instance; + int done = 1, handled = 0; + unsigned char basr; + + INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO); + + /* Look for pending interrupts */ + basr = NCR5380_read(BUS_AND_STATUS_REG); + INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr); + /* dispatch to appropriate routine if found and done=0 */ + if (basr & BASR_IRQ) { + NCR_PRINT(NDEBUG_INTR); + if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) { + done = 0; + ENABLE_IRQ(); + INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO); + NCR5380_reselect(instance); + (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); + } + else if (basr & BASR_PARITY_ERROR) { + INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO); + (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); + } + else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) { + INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO); + (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG); + } + else { + /* + * The rest of the interrupt conditions can occur only during a + * DMA transfer + */ + +#if defined(REAL_DMA) + /* + * We should only get PHASE MISMATCH and EOP interrupts if we have + * DMA enabled, so do a sanity check based on the current setting + * of the MODE register. + */ + + if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) && + ((basr & BASR_END_DMA_TRANSFER) || + !(basr & BASR_PHASE_MATCH))) { + + INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO); + NCR5380_dma_complete( instance ); + done = 0; + ENABLE_IRQ(); + } else +#endif /* REAL_DMA */ + { +/* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */ + if (basr & BASR_PHASE_MATCH) + printk(KERN_NOTICE "scsi%d: unknown interrupt, " + "BASR 0x%x, MR 0x%x, SR 0x%x\n", + HOSTNO, basr, NCR5380_read(MODE_REG), + NCR5380_read(STATUS_REG)); + (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); + } + } /* if !(SELECTION || PARITY) */ + handled = 1; + } /* BASR & IRQ */ + else { + printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, " + "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr, + NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG)); + (void) NCR5380_read(RESET_PARITY_INTERRUPT_REG); + } + + if (!done) { + INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO); + /* Put a call to NCR5380_main() on the queue... */ + queue_main(); + } + return IRQ_RETVAL(handled); +} + +#ifdef NCR5380_STATS +static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd* cmd) +{ +# ifdef NCR5380_STAT_LIMIT + if (cmd->request_bufflen > NCR5380_STAT_LIMIT) +# endif + switch (cmd->cmnd[0]) + { + case WRITE: + case WRITE_6: + case WRITE_10: + hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase); + /*hostdata->bytes_write[cmd->device->id] += cmd->request_bufflen;*/ + hostdata->pendingw--; + break; + case READ: + case READ_6: + case READ_10: + hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase); + /*hostdata->bytes_read[cmd->device->id] += cmd->request_bufflen;*/ + hostdata->pendingr--; + break; + } +} +#endif + +/* + * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, + * int tag); + * + * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command, + * including ARBITRATION, SELECTION, and initial message out for + * IDENTIFY and queue messages. + * + * Inputs : instance - instantiation of the 5380 driver on which this + * target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for + * new tag, TAG_NONE for untagged queueing, otherwise set to the tag for + * the command that is presently connected. + * + * Returns : -1 if selection could not execute for some reason, + * 0 if selection succeeded or failed because the target + * did not respond. + * + * Side effects : + * If bus busy, arbitration failed, etc, NCR5380_select() will exit + * with registers as they should have been on entry - ie + * SELECT_ENABLE will be set appropriately, the NCR5380 + * will cease to drive any SCSI bus signals. + * + * If successful : I_T_L or I_T_L_Q nexus will be established, + * instance->connected will be set to cmd. + * SELECT interrupt will be disabled. + * + * If failed (no target) : cmd->scsi_done() will be called, and the + * cmd->result host byte set to DID_BAD_TARGET. + */ + +static int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag) +{ + SETUP_HOSTDATA(instance); + unsigned char tmp[3], phase; + unsigned char *data; + int len; + unsigned long timeout; + unsigned long flags; + + hostdata->restart_select = 0; + NCR_PRINT(NDEBUG_ARBITRATION); + ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO, + instance->this_id); + + /* + * Set the phase bits to 0, otherwise the NCR5380 won't drive the + * data bus during SELECTION. + */ + + local_irq_save(flags); + if (hostdata->connected) { + local_irq_restore(flags); + return -1; + } + NCR5380_write(TARGET_COMMAND_REG, 0); + + + /* + * Start arbitration. + */ + + NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); + NCR5380_write(MODE_REG, MR_ARBITRATE); + + local_irq_restore(flags); + + /* Wait for arbitration logic to complete */ +#if NCR_TIMEOUT + { + unsigned long timeout = jiffies + 2*NCR_TIMEOUT; + + while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) + && time_before(jiffies, timeout) && !hostdata->connected) + ; + if (time_after_eq(jiffies, timeout)) + { + printk("scsi : arbitration timeout at %d\n", __LINE__); + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + return -1; + } + } +#else /* NCR_TIMEOUT */ + while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) + && !hostdata->connected); +#endif + + ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO); + + if (hostdata->connected) { + NCR5380_write(MODE_REG, MR_BASE); + return -1; + } + /* + * The arbitration delay is 2.2us, but this is a minimum and there is + * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate + * the integral nature of udelay(). + * + */ + + udelay(3); + + /* Check for lost arbitration */ + if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || + (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) || + (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || + hostdata->connected) { + NCR5380_write(MODE_REG, MR_BASE); + ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n", + HOSTNO); + return -1; + } + + /* after/during arbitration, BSY should be asserted. + IBM DPES-31080 Version S31Q works now */ + /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_SEL | + ICR_ASSERT_BSY ) ; + + if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) || + hostdata->connected) { + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n", + HOSTNO); + return -1; + } + + /* + * Again, bus clear + bus settle time is 1.2us, however, this is + * a minimum so we'll udelay ceil(1.2) + */ + +#ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY + /* ++roman: But some targets (see above :-) seem to need a bit more... */ + udelay(15); +#else + udelay(2); +#endif + + if (hostdata->connected) { + NCR5380_write(MODE_REG, MR_BASE); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + return -1; + } + + ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO); + + /* + * Now that we have won arbitration, start Selection process, asserting + * the host and target ID's on the SCSI bus. + */ + + NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id))); + + /* + * Raise ATN while SEL is true before BSY goes false from arbitration, + * since this is the only way to guarantee that we'll get a MESSAGE OUT + * phase immediately after selection. + */ + + NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY | + ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL )); + NCR5380_write(MODE_REG, MR_BASE); + + /* + * Reselect interrupts must be turned off prior to the dropping of BSY, + * otherwise we will trigger an interrupt. + */ + + if (hostdata->connected) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + return -1; + } + + NCR5380_write(SELECT_ENABLE_REG, 0); + + /* + * The initiator shall then wait at least two deskew delays and release + * the BSY signal. + */ + udelay(1); /* wingel -- wait two bus deskew delay >2*45ns */ + + /* Reset BSY */ + NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA | + ICR_ASSERT_ATN | ICR_ASSERT_SEL)); + + /* + * Something weird happens when we cease to drive BSY - looks + * like the board/chip is letting us do another read before the + * appropriate propagation delay has expired, and we're confusing + * a BSY signal from ourselves as the target's response to SELECTION. + * + * A small delay (the 'C++' frontend breaks the pipeline with an + * unnecessary jump, making it work on my 386-33/Trantor T128, the + * tighter 'C' code breaks and requires this) solves the problem - + * the 1 us delay is arbitrary, and only used because this delay will + * be the same on other platforms and since it works here, it should + * work there. + * + * wingel suggests that this could be due to failing to wait + * one deskew delay. + */ + + udelay(1); + + SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->device->id); + + /* + * The SCSI specification calls for a 250 ms timeout for the actual + * selection. + */ + + timeout = jiffies + 25; + + /* + * XXX very interesting - we're seeing a bounce where the BSY we + * asserted is being reflected / still asserted (propagation delay?) + * and it's detecting as true. Sigh. + */ + +#if 0 + /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert + * IO while SEL is true. But again, there are some disks out the in the + * world that do that nevertheless. (Somebody claimed that this announces + * reselection capability of the target.) So we better skip that test and + * only wait for BSY... (Famous german words: Der Klügere gibt nach :-) + */ + + while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & + (SR_BSY | SR_IO))); + + if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == + (SR_SEL | SR_IO)) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + NCR5380_reselect(instance); + printk (KERN_ERR "scsi%d: reselection after won arbitration?\n", + HOSTNO); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + return -1; + } +#else + while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY)); +#endif + + /* + * No less than two deskew delays after the initiator detects the + * BSY signal is true, it shall release the SEL signal and may + * change the DATA BUS. -wingel + */ + + udelay(1); + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); + + if (!(NCR5380_read(STATUS_REG) & SR_BSY)) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + if (hostdata->targets_present & (1 << cmd->device->id)) { + printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO); + if (hostdata->restart_select) + printk(KERN_NOTICE "\trestart select\n"); + NCR_PRINT(NDEBUG_ANY); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + return -1; + } + cmd->result = DID_BAD_TARGET << 16; +#ifdef NCR5380_STATS + collect_stats(hostdata, cmd); +#endif +#ifdef SUPPORT_TAGS + cmd_free_tag( cmd ); +#endif + cmd->scsi_done(cmd); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + return 0; + } + + hostdata->targets_present |= (1 << cmd->device->id); + + /* + * Since we followed the SCSI spec, and raised ATN while SEL + * was true but before BSY was false during selection, the information + * transfer phase should be a MESSAGE OUT phase so that we can send the + * IDENTIFY message. + * + * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG + * message (2 bytes) with a tag ID that we increment with every command + * until it wraps back to 0. + * + * XXX - it turns out that there are some broken SCSI-II devices, + * which claim to support tagged queuing but fail when more than + * some number of commands are issued at once. + */ + + /* Wait for start of REQ/ACK handshake */ + while (!(NCR5380_read(STATUS_REG) & SR_REQ)); + + SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n", + HOSTNO, cmd->device->id); + tmp[0] = IDENTIFY(1, cmd->device->lun); + +#ifdef SUPPORT_TAGS + if (cmd->tag != TAG_NONE) { + tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG; + tmp[2] = cmd->tag; + len = 3; + } else + len = 1; +#else + len = 1; + cmd->tag=0; +#endif /* SUPPORT_TAGS */ + + /* Send message(s) */ + data = tmp; + phase = PHASE_MSGOUT; + NCR5380_transfer_pio(instance, &phase, &len, &data); + SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO); + /* XXX need to handle errors here */ + hostdata->connected = cmd; +#ifndef SUPPORT_TAGS + hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); +#endif + + initialize_SCp(cmd); + + + return 0; +} + +/* + * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance, + * unsigned char *phase, int *count, unsigned char **data) + * + * Purpose : transfers data in given phase using polled I/O + * + * Inputs : instance - instance of driver, *phase - pointer to + * what phase is expected, *count - pointer to number of + * bytes to transfer, **data - pointer to data pointer. + * + * Returns : -1 when different phase is entered without transferring + * maximum number of bytes, 0 if all bytes are transfered or exit + * is in same phase. + * + * Also, *phase, *count, *data are modified in place. + * + * XXX Note : handling for bus free may be useful. + */ + +/* + * Note : this code is not as quick as it could be, however it + * IS 100% reliable, and for the actual data transfer where speed + * counts, we will always do a pseudo DMA or DMA transfer. + */ + +static int NCR5380_transfer_pio( struct Scsi_Host *instance, + unsigned char *phase, int *count, + unsigned char **data) +{ + register unsigned char p = *phase, tmp; + register int c = *count; + register unsigned char *d = *data; + + /* + * The NCR5380 chip will only drive the SCSI bus when the + * phase specified in the appropriate bits of the TARGET COMMAND + * REGISTER match the STATUS REGISTER + */ + + NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); + + do { + /* + * Wait for assertion of REQ, after which the phase bits will be + * valid + */ + while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ)); + + HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO); + + /* Check for phase mismatch */ + if ((tmp & PHASE_MASK) != p) { + PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO); + NCR_PRINT_PHASE(NDEBUG_PIO); + break; + } + + /* Do actual transfer from SCSI bus to / from memory */ + if (!(p & SR_IO)) + NCR5380_write(OUTPUT_DATA_REG, *d); + else + *d = NCR5380_read(CURRENT_SCSI_DATA_REG); + + ++d; + + /* + * The SCSI standard suggests that in MSGOUT phase, the initiator + * should drop ATN on the last byte of the message phase + * after REQ has been asserted for the handshake but before + * the initiator raises ACK. + */ + + if (!(p & SR_IO)) { + if (!((p & SR_MSG) && c > 1)) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_DATA); + NCR_PRINT(NDEBUG_PIO); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_DATA | ICR_ASSERT_ACK); + } else { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_DATA | ICR_ASSERT_ATN); + NCR_PRINT(NDEBUG_PIO); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK); + } + } else { + NCR_PRINT(NDEBUG_PIO); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK); + } + + while (NCR5380_read(STATUS_REG) & SR_REQ); + + HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO); + +/* + * We have several special cases to consider during REQ/ACK handshaking : + * 1. We were in MSGOUT phase, and we are on the last byte of the + * message. ATN must be dropped as ACK is dropped. + * + * 2. We are in a MSGIN phase, and we are on the last byte of the + * message. We must exit with ACK asserted, so that the calling + * code may raise ATN before dropping ACK to reject the message. + * + * 3. ACK and ATN are clear and the target may proceed as normal. + */ + if (!(p == PHASE_MSGIN && c == 1)) { + if (p == PHASE_MSGOUT && c > 1) + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); + else + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + } + } while (--c); + + PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c); + + *count = c; + *data = d; + tmp = NCR5380_read(STATUS_REG); + /* The phase read from the bus is valid if either REQ is (already) + * asserted or if ACK hasn't been released yet. The latter is the case if + * we're in MSGIN and all wanted bytes have been received. */ + if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0)) + *phase = tmp & PHASE_MASK; + else + *phase = PHASE_UNKNOWN; + + if (!c || (*phase == p)) + return 0; + else + return -1; +} + +/* + * Function : do_abort (Scsi_Host *host) + * + * Purpose : abort the currently established nexus. Should only be + * called from a routine which can drop into a + * + * Returns : 0 on success, -1 on failure. + */ + +static int do_abort (struct Scsi_Host *host) +{ + unsigned char tmp, *msgptr, phase; + int len; + + /* Request message out phase */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); + + /* + * Wait for the target to indicate a valid phase by asserting + * REQ. Once this happens, we'll have either a MSGOUT phase + * and can immediately send the ABORT message, or we'll have some + * other phase and will have to source/sink data. + * + * We really don't care what value was on the bus or what value + * the target sees, so we just handshake. + */ + + while (!(tmp = NCR5380_read(STATUS_REG)) & SR_REQ); + + NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); + + if ((tmp & PHASE_MASK) != PHASE_MSGOUT) { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | + ICR_ASSERT_ACK); + while (NCR5380_read(STATUS_REG) & SR_REQ); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN); + } + + tmp = ABORT; + msgptr = &tmp; + len = 1; + phase = PHASE_MSGOUT; + NCR5380_transfer_pio (host, &phase, &len, &msgptr); + + /* + * If we got here, and the command completed successfully, + * we're about to go into bus free state. + */ + + return len ? -1 : 0; +} + +#if defined(REAL_DMA) +/* + * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance, + * unsigned char *phase, int *count, unsigned char **data) + * + * Purpose : transfers data in given phase using either real + * or pseudo DMA. + * + * Inputs : instance - instance of driver, *phase - pointer to + * what phase is expected, *count - pointer to number of + * bytes to transfer, **data - pointer to data pointer. + * + * Returns : -1 when different phase is entered without transferring + * maximum number of bytes, 0 if all bytes or transfered or exit + * is in same phase. + * + * Also, *phase, *count, *data are modified in place. + * + */ + + +static int NCR5380_transfer_dma( struct Scsi_Host *instance, + unsigned char *phase, int *count, + unsigned char **data) +{ + SETUP_HOSTDATA(instance); + register int c = *count; + register unsigned char p = *phase; + register unsigned char *d = *data; + unsigned char tmp; + unsigned long flags; + + if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) { + *phase = tmp; + return -1; + } + + if (atari_read_overruns && (p & SR_IO)) { + c -= atari_read_overruns; + } + + DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n", + HOSTNO, (p & SR_IO) ? "reading" : "writing", + c, (p & SR_IO) ? "to" : "from", d); + + NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p)); + +#ifdef REAL_DMA + NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY); +#endif /* def REAL_DMA */ + + if (IS_A_TT()) { + /* On the Medusa, it is a must to initialize the DMA before + * starting the NCR. This is also the cleaner way for the TT. + */ + local_irq_save(flags); + hostdata->dma_len = (p & SR_IO) ? + NCR5380_dma_read_setup(instance, d, c) : + NCR5380_dma_write_setup(instance, d, c); + local_irq_restore(flags); + } + + if (p & SR_IO) + NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0); + else { + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA); + NCR5380_write(START_DMA_SEND_REG, 0); + } + + if (!IS_A_TT()) { + /* On the Falcon, the DMA setup must be done after the last */ + /* NCR access, else the DMA setup gets trashed! + */ + local_irq_save(flags); + hostdata->dma_len = (p & SR_IO) ? + NCR5380_dma_read_setup(instance, d, c) : + NCR5380_dma_write_setup(instance, d, c); + local_irq_restore(flags); + } + return 0; +} +#endif /* defined(REAL_DMA) */ + +/* + * Function : NCR5380_information_transfer (struct Scsi_Host *instance) + * + * Purpose : run through the various SCSI phases and do as the target + * directs us to. Operates on the currently connected command, + * instance->connected. + * + * Inputs : instance, instance for which we are doing commands + * + * Side effects : SCSI things happen, the disconnected queue will be + * modified if a command disconnects, *instance->connected will + * change. + * + * XXX Note : we need to watch for bus free or a reset condition here + * to recover from an unexpected bus free condition. + */ + +static void NCR5380_information_transfer (struct Scsi_Host *instance) +{ + SETUP_HOSTDATA(instance); + unsigned long flags; + unsigned char msgout = NOP; + int sink = 0; + int len; +#if defined(REAL_DMA) + int transfersize; +#endif + unsigned char *data; + unsigned char phase, tmp, extended_msg[10], old_phase=0xff; + Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected; + + while (1) { + tmp = NCR5380_read(STATUS_REG); + /* We only have a valid SCSI phase when REQ is asserted */ + if (tmp & SR_REQ) { + phase = (tmp & PHASE_MASK); + if (phase != old_phase) { + old_phase = phase; + NCR_PRINT_PHASE(NDEBUG_INFORMATION); + } + + if (sink && (phase != PHASE_MSGOUT)) { + NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp)); + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN | + ICR_ASSERT_ACK); + while (NCR5380_read(STATUS_REG) & SR_REQ); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_ATN); + sink = 0; + continue; + } + + switch (phase) { + case PHASE_DATAOUT: +#if (NDEBUG & NDEBUG_NO_DATAOUT) + printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT " + "aborted\n", HOSTNO); + sink = 1; + do_abort(instance); + cmd->result = DID_ERROR << 16; + cmd->done(cmd); + return; +#endif + case PHASE_DATAIN: + /* + * If there is no room left in the current buffer in the + * scatter-gather list, move onto the next one. + */ + + if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) { + ++cmd->SCp.buffer; + --cmd->SCp.buffers_residual; + cmd->SCp.this_residual = cmd->SCp.buffer->length; + cmd->SCp.ptr = page_address(cmd->SCp.buffer->page)+ + cmd->SCp.buffer->offset; + /* ++roman: Try to merge some scatter-buffers if + * they are at contiguous physical addresses. + */ + merge_contiguous_buffers( cmd ); + INF_PRINTK("scsi%d: %d bytes and %d buffers left\n", + HOSTNO, cmd->SCp.this_residual, + cmd->SCp.buffers_residual); + } + + /* + * The preferred transfer method is going to be + * PSEUDO-DMA for systems that are strictly PIO, + * since we can let the hardware do the handshaking. + * + * For this to work, we need to know the transfersize + * ahead of time, since the pseudo-DMA code will sit + * in an unconditional loop. + */ + +/* ++roman: I suggest, this should be + * #if def(REAL_DMA) + * instead of leaving REAL_DMA out. + */ + +#if defined(REAL_DMA) + if (!cmd->device->borken && + (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) { + len = transfersize; + cmd->SCp.phase = phase; + if (NCR5380_transfer_dma(instance, &phase, + &len, (unsigned char **) &cmd->SCp.ptr)) { + /* + * If the watchdog timer fires, all future + * accesses to this device will use the + * polled-IO. */ + printk(KERN_NOTICE "scsi%d: switching target %d " + "lun %d to slow handshake\n", HOSTNO, + cmd->device->id, cmd->device->lun); + cmd->device->borken = 1; + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_ATN); + sink = 1; + do_abort(instance); + cmd->result = DID_ERROR << 16; + cmd->done(cmd); + /* XXX - need to source or sink data here, as appropriate */ + } else { +#ifdef REAL_DMA + /* ++roman: When using real DMA, + * information_transfer() should return after + * starting DMA since it has nothing more to + * do. + */ + return; +#else + cmd->SCp.this_residual -= transfersize - len; +#endif + } + } else +#endif /* defined(REAL_DMA) */ + NCR5380_transfer_pio(instance, &phase, + (int *) &cmd->SCp.this_residual, (unsigned char **) + &cmd->SCp.ptr); + break; + case PHASE_MSGIN: + len = 1; + data = &tmp; + NCR5380_write(SELECT_ENABLE_REG, 0); /* disable reselects */ + NCR5380_transfer_pio(instance, &phase, &len, &data); + cmd->SCp.Message = tmp; + + switch (tmp) { + /* + * Linking lets us reduce the time required to get the + * next command out to the device, hopefully this will + * mean we don't waste another revolution due to the delays + * required by ARBITRATION and another SELECTION. + * + * In the current implementation proposal, low level drivers + * merely have to start the next command, pointed to by + * next_link, done() is called as with unlinked commands. + */ +#ifdef LINKED + case LINKED_CMD_COMPLETE: + case LINKED_FLG_CMD_COMPLETE: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + + LNK_PRINTK("scsi%d: target %d lun %d linked command " + "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun); + + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + /* + * Sanity check : A linked command should only terminate + * with one of these messages if there are more linked + * commands available. + */ + + if (!cmd->next_link) { + printk(KERN_NOTICE "scsi%d: target %d lun %d " + "linked command complete, no next_link\n", + HOSTNO, cmd->device->id, cmd->device->lun); + sink = 1; + do_abort (instance); + return; + } + + initialize_SCp(cmd->next_link); + /* The next command is still part of this process; copy it + * and don't free it! */ + cmd->next_link->tag = cmd->tag; + cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); + LNK_PRINTK("scsi%d: target %d lun %d linked request " + "done, calling scsi_done().\n", + HOSTNO, cmd->device->id, cmd->device->lun); +#ifdef NCR5380_STATS + collect_stats(hostdata, cmd); +#endif + cmd->scsi_done(cmd); + cmd = hostdata->connected; + break; +#endif /* def LINKED */ + case ABORT: + case COMMAND_COMPLETE: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + /* ++guenther: possible race with Falcon locking */ + falcon_dont_release++; + hostdata->connected = NULL; + QU_PRINTK("scsi%d: command for target %d, lun %d " + "completed\n", HOSTNO, cmd->device->id, cmd->device->lun); +#ifdef SUPPORT_TAGS + cmd_free_tag( cmd ); + if (status_byte(cmd->SCp.Status) == QUEUE_FULL) { + /* Turn a QUEUE FULL status into BUSY, I think the + * mid level cannot handle QUEUE FULL :-( (The + * command is retried after BUSY). Also update our + * queue size to the number of currently issued + * commands now. + */ + /* ++Andreas: the mid level code knows about + QUEUE_FULL now. */ + TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun]; + TAG_PRINTK("scsi%d: target %d lun %d returned " + "QUEUE_FULL after %d commands\n", + HOSTNO, cmd->device->id, cmd->device->lun, + ta->nr_allocated); + if (ta->queue_size > ta->nr_allocated) + ta->nr_allocated = ta->queue_size; + } +#else + hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); +#endif + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + + /* + * I'm not sure what the correct thing to do here is : + * + * If the command that just executed is NOT a request + * sense, the obvious thing to do is to set the result + * code to the values of the stored parameters. + * + * If it was a REQUEST SENSE command, we need some way to + * differentiate between the failure code of the original + * and the failure code of the REQUEST sense - the obvious + * case is success, where we fall through and leave the + * result code unchanged. + * + * The non-obvious place is where the REQUEST SENSE failed + */ + + if (cmd->cmnd[0] != REQUEST_SENSE) + cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8); + else if (status_byte(cmd->SCp.Status) != GOOD) + cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16); + +#ifdef AUTOSENSE + if ((cmd->cmnd[0] != REQUEST_SENSE) && + (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) { + ASEN_PRINTK("scsi%d: performing request sense\n", + HOSTNO); + cmd->cmnd[0] = REQUEST_SENSE; + cmd->cmnd[1] &= 0xe0; + cmd->cmnd[2] = 0; + cmd->cmnd[3] = 0; + cmd->cmnd[4] = sizeof(cmd->sense_buffer); + cmd->cmnd[5] = 0; + cmd->cmd_len = COMMAND_SIZE(cmd->cmnd[0]); + + cmd->use_sg = 0; + /* this is initialized from initialize_SCp + cmd->SCp.buffer = NULL; + cmd->SCp.buffers_residual = 0; + */ + cmd->request_buffer = (char *) cmd->sense_buffer; + cmd->request_bufflen = sizeof(cmd->sense_buffer); + + local_irq_save(flags); + LIST(cmd,hostdata->issue_queue); + NEXT(cmd) = hostdata->issue_queue; + hostdata->issue_queue = (Scsi_Cmnd *) cmd; + local_irq_restore(flags); + QU_PRINTK("scsi%d: REQUEST SENSE added to head of " + "issue queue\n", H_NO(cmd)); + } else +#endif /* def AUTOSENSE */ + { +#ifdef NCR5380_STATS + collect_stats(hostdata, cmd); +#endif + cmd->scsi_done(cmd); + } + + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + /* + * Restore phase bits to 0 so an interrupted selection, + * arbitration can resume. + */ + NCR5380_write(TARGET_COMMAND_REG, 0); + + while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) + barrier(); + + falcon_dont_release--; + /* ++roman: For Falcon SCSI, release the lock on the + * ST-DMA here if no other commands are waiting on the + * disconnected queue. + */ + falcon_release_lock_if_possible( hostdata ); + return; + case MESSAGE_REJECT: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + switch (hostdata->last_message) { + case HEAD_OF_QUEUE_TAG: + case ORDERED_QUEUE_TAG: + case SIMPLE_QUEUE_TAG: + /* The target obviously doesn't support tagged + * queuing, even though it announced this ability in + * its INQUIRY data ?!? (maybe only this LUN?) Ok, + * clear 'tagged_supported' and lock the LUN, since + * the command is treated as untagged further on. + */ + cmd->device->tagged_supported = 0; + hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun); + cmd->tag = TAG_NONE; + TAG_PRINTK("scsi%d: target %d lun %d rejected " + "QUEUE_TAG message; tagged queuing " + "disabled\n", + HOSTNO, cmd->device->id, cmd->device->lun); + break; + } + break; + case DISCONNECT: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + local_irq_save(flags); + cmd->device->disconnect = 1; + LIST(cmd,hostdata->disconnected_queue); + NEXT(cmd) = hostdata->disconnected_queue; + hostdata->connected = NULL; + hostdata->disconnected_queue = cmd; + local_irq_restore(flags); + QU_PRINTK("scsi%d: command for target %d lun %d was " + "moved from connected to the " + "disconnected_queue\n", HOSTNO, + cmd->device->id, cmd->device->lun); + /* + * Restore phase bits to 0 so an interrupted selection, + * arbitration can resume. + */ + NCR5380_write(TARGET_COMMAND_REG, 0); + + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + /* Wait for bus free to avoid nasty timeouts */ + while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected) + barrier(); + return; + /* + * The SCSI data pointer is *IMPLICITLY* saved on a disconnect + * operation, in violation of the SCSI spec so we can safely + * ignore SAVE/RESTORE pointers calls. + * + * Unfortunately, some disks violate the SCSI spec and + * don't issue the required SAVE_POINTERS message before + * disconnecting, and we have to break spec to remain + * compatible. + */ + case SAVE_POINTERS: + case RESTORE_POINTERS: + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + /* Enable reselect interrupts */ + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + break; + case EXTENDED_MESSAGE: +/* + * Extended messages are sent in the following format : + * Byte + * 0 EXTENDED_MESSAGE == 1 + * 1 length (includes one byte for code, doesn't + * include first two bytes) + * 2 code + * 3..length+1 arguments + * + * Start the extended message buffer with the EXTENDED_MESSAGE + * byte, since print_msg() wants the whole thing. + */ + extended_msg[0] = EXTENDED_MESSAGE; + /* Accept first byte by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + + EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO); + + len = 2; + data = extended_msg + 1; + phase = PHASE_MSGIN; + NCR5380_transfer_pio(instance, &phase, &len, &data); + EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO, + (int)extended_msg[1], (int)extended_msg[2]); + + if (!len && extended_msg[1] <= + (sizeof (extended_msg) - 1)) { + /* Accept third byte by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + len = extended_msg[1] - 1; + data = extended_msg + 3; + phase = PHASE_MSGIN; + + NCR5380_transfer_pio(instance, &phase, &len, &data); + EXT_PRINTK("scsi%d: message received, residual %d\n", + HOSTNO, len); + + switch (extended_msg[2]) { + case EXTENDED_SDTR: + case EXTENDED_WDTR: + case EXTENDED_MODIFY_DATA_POINTER: + case EXTENDED_EXTENDED_IDENTIFY: + tmp = 0; + } + } else if (len) { + printk(KERN_NOTICE "scsi%d: error receiving " + "extended message\n", HOSTNO); + tmp = 0; + } else { + printk(KERN_NOTICE "scsi%d: extended message " + "code %02x length %d is too long\n", + HOSTNO, extended_msg[2], extended_msg[1]); + tmp = 0; + } + /* Fall through to reject message */ + + /* + * If we get something weird that we aren't expecting, + * reject it. + */ + default: + if (!tmp) { + printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO); + print_msg (extended_msg); + printk("\n"); + } else if (tmp != EXTENDED_MESSAGE) + printk(KERN_DEBUG "scsi%d: rejecting unknown " + "message %02x from target %d, lun %d\n", + HOSTNO, tmp, cmd->device->id, cmd->device->lun); + else + printk(KERN_DEBUG "scsi%d: rejecting unknown " + "extended message " + "code %02x, length %d from target %d, lun %d\n", + HOSTNO, extended_msg[1], extended_msg[0], + cmd->device->id, cmd->device->lun); + + + msgout = MESSAGE_REJECT; + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | + ICR_ASSERT_ATN); + break; + } /* switch (tmp) */ + break; + case PHASE_MSGOUT: + len = 1; + data = &msgout; + hostdata->last_message = msgout; + NCR5380_transfer_pio(instance, &phase, &len, &data); + if (msgout == ABORT) { +#ifdef SUPPORT_TAGS + cmd_free_tag( cmd ); +#else + hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); +#endif + hostdata->connected = NULL; + cmd->result = DID_ERROR << 16; +#ifdef NCR5380_STATS + collect_stats(hostdata, cmd); +#endif + cmd->scsi_done(cmd); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + falcon_release_lock_if_possible( hostdata ); + return; + } + msgout = NOP; + break; + case PHASE_CMDOUT: + len = cmd->cmd_len; + data = cmd->cmnd; + /* + * XXX for performance reasons, on machines with a + * PSEUDO-DMA architecture we should probably + * use the dma transfer function. + */ + NCR5380_transfer_pio(instance, &phase, &len, + &data); + break; + case PHASE_STATIN: + len = 1; + data = &tmp; + NCR5380_transfer_pio(instance, &phase, &len, &data); + cmd->SCp.Status = tmp; + break; + default: + printk("scsi%d: unknown phase\n", HOSTNO); + NCR_PRINT(NDEBUG_ANY); + } /* switch(phase) */ + } /* if (tmp * SR_REQ) */ + } /* while (1) */ +} + +/* + * Function : void NCR5380_reselect (struct Scsi_Host *instance) + * + * Purpose : does reselection, initializing the instance->connected + * field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q + * nexus has been reestablished, + * + * Inputs : instance - this instance of the NCR5380. + * + */ + + +static void NCR5380_reselect (struct Scsi_Host *instance) +{ + SETUP_HOSTDATA(instance); + unsigned char target_mask; + unsigned char lun, phase; + int len; +#ifdef SUPPORT_TAGS + unsigned char tag; +#endif + unsigned char msg[3]; + unsigned char *data; + Scsi_Cmnd *tmp = NULL, *prev; +/* unsigned long flags; */ + + /* + * Disable arbitration, etc. since the host adapter obviously + * lost, and tell an interrupted NCR5380_select() to restart. + */ + + NCR5380_write(MODE_REG, MR_BASE); + hostdata->restart_select = 1; + + target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask); + + RSL_PRINTK("scsi%d: reselect\n", HOSTNO); + + /* + * At this point, we have detected that our SCSI ID is on the bus, + * SEL is true and BSY was false for at least one bus settle delay + * (400 ns). + * + * We must assert BSY ourselves, until the target drops the SEL + * signal. + */ + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY); + + while (NCR5380_read(STATUS_REG) & SR_SEL); + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + + /* + * Wait for target to go into MSGIN. + */ + + while (!(NCR5380_read(STATUS_REG) & SR_REQ)); + + len = 1; + data = msg; + phase = PHASE_MSGIN; + NCR5380_transfer_pio(instance, &phase, &len, &data); + + if (!(msg[0] & 0x80)) { + printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO); + print_msg(msg); + do_abort(instance); + return; + } + lun = (msg[0] & 0x07); + +#ifdef SUPPORT_TAGS + /* If the phase is still MSGIN, the target wants to send some more + * messages. In case it supports tagged queuing, this is probably a + * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus. + */ + tag = TAG_NONE; + if (phase == PHASE_MSGIN && setup_use_tagged_queuing) { + /* Accept previous IDENTIFY message by clearing ACK */ + NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE ); + len = 2; + data = msg+1; + if (!NCR5380_transfer_pio(instance, &phase, &len, &data) && + msg[1] == SIMPLE_QUEUE_TAG) + tag = msg[2]; + TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at " + "reselection\n", HOSTNO, target_mask, lun, tag); + } +#endif + + /* + * Find the command corresponding to the I_T_L or I_T_L_Q nexus we + * just reestablished, and remove it from the disconnected queue. + */ + + for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL; + tmp; prev = tmp, tmp = NEXT(tmp) ) { + if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun) +#ifdef SUPPORT_TAGS + && (tag == tmp->tag) +#endif + ) { + /* ++guenther: prevent race with falcon_release_lock */ + falcon_dont_release++; + if (prev) { + REMOVE(prev, NEXT(prev), tmp, NEXT(tmp)); + NEXT(prev) = NEXT(tmp); + } else { + REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp)); + hostdata->disconnected_queue = NEXT(tmp); + } + NEXT(tmp) = NULL; + break; + } + } + + if (!tmp) { + printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d " +#ifdef SUPPORT_TAGS + "tag %d " +#endif + "not in disconnected_queue.\n", + HOSTNO, target_mask, lun +#ifdef SUPPORT_TAGS + , tag +#endif + ); + /* + * Since we have an established nexus that we can't do anything + * with, we must abort it. + */ + do_abort(instance); + return; + } + + /* Accept message by clearing ACK */ + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + + hostdata->connected = tmp; + RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n", + HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag); + falcon_dont_release--; +} + + +/* + * Function : int NCR5380_abort (Scsi_Cmnd *cmd) + * + * Purpose : abort a command + * + * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the + * host byte of the result field to, if zero DID_ABORTED is + * used. + * + * Returns : 0 - success, -1 on failure. + * + * XXX - there is no way to abort the command that is currently + * connected, you have to wait for it to complete. If this is + * a problem, we could implement longjmp() / setjmp(), setjmp() + * called where the loop started in NCR5380_main(). + */ + +static +int NCR5380_abort (Scsi_Cmnd *cmd) +{ + struct Scsi_Host *instance = cmd->device->host; + SETUP_HOSTDATA(instance); + Scsi_Cmnd *tmp, **prev; + unsigned long flags; + + printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO); + print_Scsi_Cmnd (cmd); + + NCR5380_print_status (instance); + + local_irq_save(flags); + + if (!IS_A_TT() && !falcon_got_lock) + printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n", + HOSTNO); + + ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO, + NCR5380_read(BUS_AND_STATUS_REG), + NCR5380_read(STATUS_REG)); + +#if 1 +/* + * Case 1 : If the command is the currently executing command, + * we'll set the aborted flag and return control so that + * information transfer routine can exit cleanly. + */ + + if (hostdata->connected == cmd) { + + ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO); +/* + * We should perform BSY checking, and make sure we haven't slipped + * into BUS FREE. + */ + +/* NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */ +/* + * Since we can't change phases until we've completed the current + * handshake, we have to source or sink a byte of data if the current + * phase is not MSGOUT. + */ + +/* + * Return control to the executing NCR drive so we can clear the + * aborted flag and get back into our main loop. + */ + + if (do_abort(instance) == 0) { + hostdata->aborted = 1; + hostdata->connected = NULL; + cmd->result = DID_ABORT << 16; +#ifdef SUPPORT_TAGS + cmd_free_tag( cmd ); +#else + hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); +#endif + local_irq_restore(flags); + cmd->scsi_done(cmd); + falcon_release_lock_if_possible( hostdata ); + return SCSI_ABORT_SUCCESS; + } else { +/* local_irq_restore(flags); */ + printk("scsi%d: abort of connected command failed!\n", HOSTNO); + return SCSI_ABORT_ERROR; + } + } +#endif + +/* + * Case 2 : If the command hasn't been issued yet, we simply remove it + * from the issue queue. + */ + for (prev = (Scsi_Cmnd **) &(hostdata->issue_queue), + tmp = (Scsi_Cmnd *) hostdata->issue_queue; + tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) ) + if (cmd == tmp) { + REMOVE(5, *prev, tmp, NEXT(tmp)); + (*prev) = NEXT(tmp); + NEXT(tmp) = NULL; + tmp->result = DID_ABORT << 16; + local_irq_restore(flags); + ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n", + HOSTNO); + /* Tagged queuing note: no tag to free here, hasn't been assigned + * yet... */ + tmp->scsi_done(tmp); + falcon_release_lock_if_possible( hostdata ); + return SCSI_ABORT_SUCCESS; + } + +/* + * Case 3 : If any commands are connected, we're going to fail the abort + * and let the high level SCSI driver retry at a later time or + * issue a reset. + * + * Timeouts, and therefore aborted commands, will be highly unlikely + * and handling them cleanly in this situation would make the common + * case of noresets less efficient, and would pollute our code. So, + * we fail. + */ + + if (hostdata->connected) { + local_irq_restore(flags); + ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO); + return SCSI_ABORT_SNOOZE; + } + +/* + * Case 4: If the command is currently disconnected from the bus, and + * there are no connected commands, we reconnect the I_T_L or + * I_T_L_Q nexus associated with it, go into message out, and send + * an abort message. + * + * This case is especially ugly. In order to reestablish the nexus, we + * need to call NCR5380_select(). The easiest way to implement this + * function was to abort if the bus was busy, and let the interrupt + * handler triggered on the SEL for reselect take care of lost arbitrations + * where necessary, meaning interrupts need to be enabled. + * + * When interrupts are enabled, the queues may change - so we + * can't remove it from the disconnected queue before selecting it + * because that could cause a failure in hashing the nexus if that + * device reselected. + * + * Since the queues may change, we can't use the pointers from when we + * first locate it. + * + * So, we must first locate the command, and if NCR5380_select() + * succeeds, then issue the abort, relocate the command and remove + * it from the disconnected queue. + */ + + for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp; + tmp = NEXT(tmp)) + if (cmd == tmp) { + local_irq_restore(flags); + ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO); + + if (NCR5380_select (instance, cmd, (int) cmd->tag)) + return SCSI_ABORT_BUSY; + + ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO); + + do_abort (instance); + + local_irq_save(flags); + for (prev = (Scsi_Cmnd **) &(hostdata->disconnected_queue), + tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; + tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp) ) + if (cmd == tmp) { + REMOVE(5, *prev, tmp, NEXT(tmp)); + *prev = NEXT(tmp); + NEXT(tmp) = NULL; + tmp->result = DID_ABORT << 16; + /* We must unlock the tag/LUN immediately here, since the + * target goes to BUS FREE and doesn't send us another + * message (COMMAND_COMPLETE or the like) + */ +#ifdef SUPPORT_TAGS + cmd_free_tag( tmp ); +#else + hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun); +#endif + local_irq_restore(flags); + tmp->scsi_done(tmp); + falcon_release_lock_if_possible( hostdata ); + return SCSI_ABORT_SUCCESS; + } + } + +/* + * Case 5 : If we reached this point, the command was not found in any of + * the queues. + * + * We probably reached this point because of an unlikely race condition + * between the command completing successfully and the abortion code, + * so we won't panic, but we will notify the user in case something really + * broke. + */ + + local_irq_restore(flags); + printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully\n" + KERN_INFO " before abortion\n", HOSTNO); + +/* Maybe it is sufficient just to release the ST-DMA lock... (if + * possible at all) At least, we should check if the lock could be + * released after the abort, in case it is kept due to some bug. + */ + falcon_release_lock_if_possible( hostdata ); + + return SCSI_ABORT_NOT_RUNNING; +} + + +/* + * Function : int NCR5380_reset (Scsi_Cmnd *cmd) + * + * Purpose : reset the SCSI bus. + * + * Returns : SCSI_RESET_WAKEUP + * + */ + +static int NCR5380_bus_reset( Scsi_Cmnd *cmd) +{ + SETUP_HOSTDATA(cmd->device->host); + int i; + unsigned long flags; +#if 1 + Scsi_Cmnd *connected, *disconnected_queue; +#endif + + if (!IS_A_TT() && !falcon_got_lock) + printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n", + H_NO(cmd) ); + + NCR5380_print_status (cmd->device->host); + + /* get in phase */ + NCR5380_write( TARGET_COMMAND_REG, + PHASE_SR_TO_TCR( NCR5380_read(STATUS_REG) )); + /* assert RST */ + NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST ); + udelay (40); + /* reset NCR registers */ + NCR5380_write( INITIATOR_COMMAND_REG, ICR_BASE ); + NCR5380_write( MODE_REG, MR_BASE ); + NCR5380_write( TARGET_COMMAND_REG, 0 ); + NCR5380_write( SELECT_ENABLE_REG, 0 ); + /* ++roman: reset interrupt condition! otherwise no interrupts don't get + * through anymore ... */ + (void)NCR5380_read( RESET_PARITY_INTERRUPT_REG ); + +#if 1 /* XXX Should now be done by midlevel code, but it's broken XXX */ + /* XXX see below XXX */ + + /* MSch: old-style reset: actually abort all command processing here */ + + /* After the reset, there are no more connected or disconnected commands + * and no busy units; to avoid problems with re-inserting the commands + * into the issue_queue (via scsi_done()), the aborted commands are + * remembered in local variables first. + */ + local_irq_save(flags); + connected = (Scsi_Cmnd *)hostdata->connected; + hostdata->connected = NULL; + disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue; + hostdata->disconnected_queue = NULL; +#ifdef SUPPORT_TAGS + free_all_tags(); +#endif + for( i = 0; i < 8; ++i ) + hostdata->busy[i] = 0; +#ifdef REAL_DMA + hostdata->dma_len = 0; +#endif + local_irq_restore(flags); + + /* In order to tell the mid-level code which commands were aborted, + * set the command status to DID_RESET and call scsi_done() !!! + * This ultimately aborts processing of these commands in the mid-level. + */ + + if ((cmd = connected)) { + ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd)); + cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16); + cmd->scsi_done( cmd ); + } + + for (i = 0; (cmd = disconnected_queue); ++i) { + disconnected_queue = NEXT(cmd); + NEXT(cmd) = NULL; + cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16); + cmd->scsi_done( cmd ); + } + if (i > 0) + ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i); + +/* The Falcon lock should be released after a reset... + */ +/* ++guenther: moved to atari_scsi_reset(), to prevent a race between + * unlocking and enabling dma interrupt. + */ +/* falcon_release_lock_if_possible( hostdata );*/ + + /* since all commands have been explicitly terminated, we need to tell + * the midlevel code that the reset was SUCCESSFUL, and there is no + * need to 'wake up' the commands by a request_sense + */ + return SCSI_RESET_SUCCESS | SCSI_RESET_BUS_RESET; +#else /* 1 */ + + /* MSch: new-style reset handling: let the mid-level do what it can */ + + /* ++guenther: MID-LEVEL IS STILL BROKEN. + * Mid-level is supposed to requeue all commands that were active on the + * various low-level queues. In fact it does this, but that's not enough + * because all these commands are subject to timeout. And if a timeout + * happens for any removed command, *_abort() is called but all queues + * are now empty. Abort then gives up the falcon lock, which is fatal, + * since the mid-level will queue more commands and must have the lock + * (it's all happening inside timer interrupt handler!!). + * Even worse, abort will return NOT_RUNNING for all those commands not + * on any queue, so they won't be retried ... + * + * Conclusion: either scsi.c disables timeout for all resetted commands + * immediately, or we lose! As of linux-2.0.20 it doesn't. + */ + + /* After the reset, there are no more connected or disconnected commands + * and no busy units; so clear the low-level status here to avoid + * conflicts when the mid-level code tries to wake up the affected + * commands! + */ + + if (hostdata->issue_queue) + ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd)); + if (hostdata->connected) + ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd)); + if (hostdata->disconnected_queue) + ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd)); + + local_irq_save(flags); + hostdata->issue_queue = NULL; + hostdata->connected = NULL; + hostdata->disconnected_queue = NULL; +#ifdef SUPPORT_TAGS + free_all_tags(); +#endif + for( i = 0; i < 8; ++i ) + hostdata->busy[i] = 0; +#ifdef REAL_DMA + hostdata->dma_len = 0; +#endif + local_irq_restore(flags); + + /* we did no complete reset of all commands, so a wakeup is required */ + return SCSI_RESET_WAKEUP | SCSI_RESET_BUS_RESET; +#endif /* 1 */ +} + +/* Local Variables: */ +/* tab-width: 8 */ +/* End: */ |