diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/ppc64/Kconfig | 17 | ||||
| -rw-r--r-- | arch/ppc64/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/ppc64/kernel/head.S | 6 | ||||
| -rw-r--r-- | arch/ppc64/kernel/machine_kexec.c | 301 | ||||
| -rw-r--r-- | arch/ppc64/kernel/misc.S | 175 | ||||
| -rw-r--r-- | arch/ppc64/kernel/mpic.c | 29 | ||||
| -rw-r--r-- | arch/ppc64/kernel/mpic.h | 3 | ||||
| -rw-r--r-- | arch/ppc64/kernel/pSeries_setup.c | 4 | ||||
| -rw-r--r-- | arch/ppc64/kernel/setup.c | 22 | ||||
| -rw-r--r-- | arch/ppc64/kernel/xics.c | 25 |
10 files changed, 566 insertions, 17 deletions
diff --git a/arch/ppc64/Kconfig b/arch/ppc64/Kconfig index 5f40b438b58..f804f25232a 100644 --- a/arch/ppc64/Kconfig +++ b/arch/ppc64/Kconfig @@ -142,6 +142,23 @@ config PPC_SPLPAR processors, that is, which share physical processors between two or more partitions. +config KEXEC + bool "kexec system call (EXPERIMENTAL)" + depends on PPC_MULTIPLATFORM && EXPERIMENTAL + help + kexec is a system call that implements the ability to shutdown your + current kernel, and to start another kernel. It is like a reboot + but it is indepedent of the system firmware. And like a reboot + you can start any kernel with it, not just Linux. + + The name comes from the similiarity to the exec system call. + + It is an ongoing process to be certain the hardware in a machine + is properly shutdown, so do not be surprised if this code does not + initially work for you. It may help to enable device hotplugging + support. As of this writing the exact hardware interface is + strongly in flux, so no good recommendation can be made. + config IBMVIO depends on PPC_PSERIES || PPC_ISERIES bool diff --git a/arch/ppc64/kernel/Makefile b/arch/ppc64/kernel/Makefile index dffbfb7ac8d..d9b2660ef22 100644 --- a/arch/ppc64/kernel/Makefile +++ b/arch/ppc64/kernel/Makefile @@ -36,6 +36,7 @@ obj-$(CONFIG_PPC_PSERIES) += pSeries_pci.o pSeries_lpar.o pSeries_hvCall.o \ obj-$(CONFIG_PPC_BPA) += bpa_setup.o bpa_iommu.o bpa_nvram.o \ bpa_iic.o spider-pic.o +obj-$(CONFIG_KEXEC) += machine_kexec.o obj-$(CONFIG_EEH) += eeh.o obj-$(CONFIG_PROC_FS) += proc_ppc64.o obj-$(CONFIG_RTAS_FLASH) += rtas_flash.o diff --git a/arch/ppc64/kernel/head.S b/arch/ppc64/kernel/head.S index 02c8f4e3e4b..675c2708588 100644 --- a/arch/ppc64/kernel/head.S +++ b/arch/ppc64/kernel/head.S @@ -1194,7 +1194,7 @@ _GLOBAL(pSeries_secondary_smp_init) bl .__restore_cpu_setup /* Set up a paca value for this processor. Since we have the - * physical cpu id in r3, we need to search the pacas to find + * physical cpu id in r24, we need to search the pacas to find * which logical id maps to our physical one. */ LOADADDR(r13, paca) /* Get base vaddr of paca array */ @@ -1207,8 +1207,8 @@ _GLOBAL(pSeries_secondary_smp_init) cmpwi r5,NR_CPUS blt 1b -99: HMT_LOW /* Couldn't find our CPU id */ - b 99b + mr r3,r24 /* not found, copy phys to r3 */ + b .kexec_wait /* next kernel might do better */ 2: mtspr SPRG3,r13 /* Save vaddr of paca in SPRG3 */ /* From now on, r24 is expected to be logica cpuid */ diff --git a/arch/ppc64/kernel/machine_kexec.c b/arch/ppc64/kernel/machine_kexec.c new file mode 100644 index 00000000000..217965d60a4 --- /dev/null +++ b/arch/ppc64/kernel/machine_kexec.c @@ -0,0 +1,301 @@ +/* + * machine_kexec.c - handle transition of Linux booting another kernel + * + * Copyright (C) 2004-2005, IBM Corp. + * + * Created by: Milton D Miller II + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + + +#include <linux/cpumask.h> +#include <linux/kexec.h> +#include <linux/smp.h> +#include <linux/thread_info.h> +#include <linux/errno.h> + +#include <asm/page.h> +#include <asm/current.h> +#include <asm/machdep.h> +#include <asm/cacheflush.h> +#include <asm/paca.h> +#include <asm/mmu.h> +#include <asm/sections.h> /* _end */ +#include <asm/prom.h> + +#define HASH_GROUP_SIZE 0x80 /* size of each hash group, asm/mmu.h */ + +/* Have this around till we move it into crash specific file */ +note_buf_t crash_notes[NR_CPUS]; + +/* Dummy for now. Not sure if we need to have a crash shutdown in here + * and if what it will achieve. Letting it be now to compile the code + * in generic kexec environment + */ +void machine_crash_shutdown(void) +{ + /* do nothing right now */ + /* smp_relase_cpus() if we want smp on panic kernel */ + /* cpu_irq_down to isolate us until we are ready */ +} + +int machine_kexec_prepare(struct kimage *image) +{ + int i; + unsigned long begin, end; /* limits of segment */ + unsigned long low, high; /* limits of blocked memory range */ + struct device_node *node; + unsigned long *basep; + unsigned int *sizep; + + if (!ppc_md.hpte_clear_all) + return -ENOENT; + + /* + * Since we use the kernel fault handlers and paging code to + * handle the virtual mode, we must make sure no destination + * overlaps kernel static data or bss. + */ + for(i = 0; i < image->nr_segments; i++) + if (image->segment[i].mem < __pa(_end)) + return -ETXTBSY; + + /* + * For non-LPAR, we absolutely can not overwrite the mmu hash + * table, since we are still using the bolted entries in it to + * do the copy. Check that here. + * + * It is safe if the end is below the start of the blocked + * region (end <= low), or if the beginning is after the + * end of the blocked region (begin >= high). Use the + * boolean identity !(a || b) === (!a && !b). + */ + if (htab_address) { + low = __pa(htab_address); + high = low + (htab_hash_mask + 1) * HASH_GROUP_SIZE; + + for(i = 0; i < image->nr_segments; i++) { + begin = image->segment[i].mem; + end = begin + image->segment[i].memsz; + + if ((begin < high) && (end > low)) + return -ETXTBSY; + } + } + + /* We also should not overwrite the tce tables */ + for (node = of_find_node_by_type(NULL, "pci"); node != NULL; + node = of_find_node_by_type(node, "pci")) { + basep = (unsigned long *)get_property(node, "linux,tce-base", + NULL); + sizep = (unsigned int *)get_property(node, "linux,tce-size", + NULL); + if (basep == NULL || sizep == NULL) + continue; + + low = *basep; + high = low + (*sizep); + + for(i = 0; i < image->nr_segments; i++) { + begin = image->segment[i].mem; + end = begin + image->segment[i].memsz; + + if ((begin < high) && (end > low)) + return -ETXTBSY; + } + } + + return 0; +} + +void machine_kexec_cleanup(struct kimage *image) +{ + /* we do nothing in prepare that needs to be undone */ +} + +#define IND_FLAGS (IND_DESTINATION | IND_INDIRECTION | IND_DONE | IND_SOURCE) + +static void copy_segments(unsigned long ind) +{ + unsigned long entry; + unsigned long *ptr; + void *dest; + void *addr; + + /* + * We rely on kexec_load to create a lists that properly + * initializes these pointers before they are used. + * We will still crash if the list is wrong, but at least + * the compiler will be quiet. + */ + ptr = NULL; + dest = NULL; + + for (entry = ind; !(entry & IND_DONE); entry = *ptr++) { + addr = __va(entry & PAGE_MASK); + + switch (entry & IND_FLAGS) { + case IND_DESTINATION: + dest = addr; + break; + case IND_INDIRECTION: + ptr = addr; + break; + case IND_SOURCE: + copy_page(dest, addr); + dest += PAGE_SIZE; + } + } +} + +void kexec_copy_flush(struct kimage *image) +{ + long i, nr_segments = image->nr_segments; + struct kexec_segment ranges[KEXEC_SEGMENT_MAX]; + + /* save the ranges on the stack to efficiently flush the icache */ + memcpy(ranges, image->segment, sizeof(ranges)); + + /* + * After this call we may not use anything allocated in dynamic + * memory, including *image. + * + * Only globals and the stack are allowed. + */ + copy_segments(image->head); + + /* + * we need to clear the icache for all dest pages sometime, + * including ones that were in place on the original copy + */ + for (i = 0; i < nr_segments; i++) + flush_icache_range(ranges[i].mem + KERNELBASE, + ranges[i].mem + KERNELBASE + + ranges[i].memsz); +} + +#ifdef CONFIG_SMP + +/* FIXME: we should schedule this function to be called on all cpus based + * on calling the interrupts, but we would like to call it off irq level + * so that the interrupt controller is clean. + */ +void kexec_smp_down(void *arg) +{ + if (ppc_md.cpu_irq_down) + ppc_md.cpu_irq_down(); + + local_irq_disable(); + kexec_smp_wait(); + /* NOTREACHED */ +} + +static void kexec_prepare_cpus(void) +{ + int my_cpu, i, notified=-1; + + smp_call_function(kexec_smp_down, NULL, 0, /* wait */0); + my_cpu = get_cpu(); + + /* check the others cpus are now down (via paca hw cpu id == -1) */ + for (i=0; i < NR_CPUS; i++) { + if (i == my_cpu) + continue; + + while (paca[i].hw_cpu_id != -1) { + if (!cpu_possible(i)) { + printk("kexec: cpu %d hw_cpu_id %d is not" + " possible, ignoring\n", + i, paca[i].hw_cpu_id); + break; + } + if (!cpu_online(i)) { + /* Fixme: this can be spinning in + * pSeries_secondary_wait with a paca + * waiting for it to go online. + */ + printk("kexec: cpu %d hw_cpu_id %d is not" + " online, ignoring\n", + i, paca[i].hw_cpu_id); + break; + } + if (i != notified) { + printk( "kexec: waiting for cpu %d (physical" + " %d) to go down\n", + i, paca[i].hw_cpu_id); + notified = i; + } + } + } + + /* after we tell the others to go down */ + if (ppc_md.cpu_irq_down) + ppc_md.cpu_irq_down(); + + put_cpu(); + + local_irq_disable(); +} + +#else /* ! SMP */ + +static void kexec_prepare_cpus(void) +{ + /* + * move the secondarys to us so that we can copy + * the new kernel 0-0x100 safely + * + * do this if kexec in setup.c ? + */ + smp_relase_cpus(); + if (ppc_md.cpu_irq_down) + ppc_md.cpu_irq_down(); + local_irq_disable(); +} + +#endif /* SMP */ + +/* + * kexec thread structure and stack. + * + * We need to make sure that this is 16384-byte aligned due to the + * way process stacks are handled. It also must be statically allocated + * or allocated as part of the kimage, because everything else may be + * overwritten when we copy the kexec image. We piggyback on the + * "init_task" linker section here to statically allocate a stack. + * + * We could use a smaller stack if we don't care about anything using + * current, but that audit has not been performed. + */ +union thread_union kexec_stack + __attribute__((__section__(".data.init_task"))) = { }; + +/* Our assembly helper, in kexec_stub.S */ +extern NORET_TYPE void kexec_sequence(void *newstack, unsigned long start, + void *image, void *control, void (*clear_all)(void)) ATTRIB_NORET; + +/* too late to fail here */ +void machine_kexec(struct kimage *image) +{ + + /* prepare control code if any */ + + /* shutdown other cpus into our wait loop and quiesce interrupts */ + kexec_prepare_cpus(); + + /* switch to a staticly allocated stack. Based on irq stack code. + * XXX: the task struct will likely be invalid once we do the copy! + */ + kexec_stack.thread_info.task = current_thread_info()->task; + kexec_stack.thread_info.flags = 0; + + /* Some things are best done in assembly. Finding globals with + * a toc is easier in C, so pass in what we can. + */ + kexec_sequence(&kexec_stack, image->start, image, + page_address(image->control_code_page), + ppc_md.hpte_clear_all); + /* NOTREACHED */ +} diff --git a/arch/ppc64/kernel/misc.S b/arch/ppc64/kernel/misc.S index e3c73b3425d..f3dea0c5a88 100644 --- a/arch/ppc64/kernel/misc.S +++ b/arch/ppc64/kernel/misc.S @@ -680,6 +680,177 @@ _GLOBAL(kernel_thread) ld r30,-16(r1) blr +/* kexec_wait(phys_cpu) + * + * wait for the flag to change, indicating this kernel is going away but + * the slave code for the next one is at addresses 0 to 100. + * + * This is used by all slaves. + * + * Physical (hardware) cpu id should be in r3. + */ +_GLOBAL(kexec_wait) + bl 1f +1: mflr r5 + addi r5,r5,kexec_flag-1b + +99: HMT_LOW +#ifdef CONFIG_KEXEC /* use no memory without kexec */ + lwz r4,0(r5) + cmpwi 0,r4,0 + bnea 0x60 +#endif + b 99b + +/* this can be in text because we won't change it until we are + * running in real anyways + */ +kexec_flag: + .long 0 + + +#ifdef CONFIG_KEXEC + +/* kexec_smp_wait(void) + * + * call with interrupts off + * note: this is a terminal routine, it does not save lr + * + * get phys id from paca + * set paca id to -1 to say we got here + * switch to real mode + * join other cpus in kexec_wait(phys_id) + */ +_GLOBAL(kexec_smp_wait) + lhz r3,PACAHWCPUID(r13) + li r4,-1 + sth r4,PACAHWCPUID(r13) /* let others know we left */ + bl real_mode + b .kexec_wait + +/* + * switch to real mode (turn mmu off) + * we use the early kernel trick that the hardware ignores bits + * 0 and 1 (big endian) of the effective address in real mode + * + * don't overwrite r3 here, it is live for kexec_wait above. + */ +real_mode: /* assume normal blr return */ +1: li r9,MSR_RI + li r10,MSR_DR|MSR_IR + mflr r11 /* return address to SRR0 */ + mfmsr r12 + andc r9,r12,r9 + andc r10,r12,r10 + + mtmsrd r9,1 + mtspr SPRN_SRR1,r10 + mtspr SPRN_SRR0,r11 + rfid + + +/* + * kexec_sequence(newstack, start, image, control, clear_all()) + * + * does the grungy work with stack switching and real mode switches + * also does simple calls to other code + */ + +_GLOBAL(kexec_sequence) + mflr r0 + std r0,16(r1) + + /* switch stacks to newstack -- &kexec_stack.stack */ + stdu r1,THREAD_SIZE-112(r3) + mr r1,r3 + + li r0,0 + std r0,16(r1) + + /* save regs for local vars on new stack. + * yes, we won't go back, but ... + */ + std r31,-8(r1) + std r30,-16(r1) + std r29,-24(r1) + std r28,-32(r1) + std r27,-40(r1) + std r26,-48(r1) + std r25,-56(r1) + + stdu r1,-112-64(r1) + + /* save args into preserved regs */ + mr r31,r3 /* newstack (both) */ + mr r30,r4 /* start (real) */ + mr r29,r5 /* image (virt) */ + mr r28,r6 /* control, unused */ + mr r27,r7 /* clear_all() fn desc */ + mr r26,r8 /* spare */ + lhz r25,PACAHWCPUID(r13) /* get our phys cpu from paca */ + + /* disable interrupts, we are overwriting kernel data next */ + mfmsr r3 + rlwinm r3,r3,0,17,15 + mtmsrd r3,1 + + /* copy dest pages, flush whole dest image */ + mr r3,r29 + bl .kexec_copy_flush /* (image) */ + + /* turn off mmu */ + bl real_mode + + /* clear out hardware hash page table and tlb */ + ld r5,0(r27) /* deref function descriptor */ + mtctr r5 + bctrl /* ppc_md.hash_clear_all(void); */ + +/* + * kexec image calling is: + * the first 0x100 bytes of the entry point are copied to 0 + * + * all slaves branch to slave = 0x60 (absolute) + * slave(phys_cpu_id); + * + * master goes to start = entry point + * start(phys_cpu_id, start, 0); + * + * + * a wrapper is needed to call existing kernels, here is an approximate + * description of one method: + * + * v2: (2.6.10) + * start will be near the boot_block (maybe 0x100 bytes before it?) + * it will have a 0x60, which will b to boot_block, where it will wait + * and 0 will store phys into struct boot-block and load r3 from there, + * copy kernel 0-0x100 and tell slaves to back down to 0x60 again + * + * v1: (2.6.9) + * boot block will have all cpus scanning device tree to see if they + * are the boot cpu ????? + * other device tree differences (prop sizes, va vs pa, etc)... + */ + + /* copy 0x100 bytes starting at start to 0 */ + li r3,0 + mr r4,r30 + li r5,0x100 + li r6,0 + bl .copy_and_flush /* (dest, src, copy limit, start offset) */ +1: /* assume normal blr return */ + + /* release other cpus to the new kernel secondary start at 0x60 */ + mflr r5 + li r6,1 + stw r6,kexec_flag-1b(5) + mr r3,r25 # my phys cpu + mr r4,r30 # start, aka phys mem offset + mtlr 4 + li r5,0 + blr /* image->start(physid, image->start, 0); */ +#endif /* CONFIG_KEXEC */ + /* Why isn't this a) automatic, b) written in 'C'? */ .balign 8 _GLOBAL(sys_call_table32) @@ -951,7 +1122,7 @@ _GLOBAL(sys_call_table32) .llong .compat_sys_mq_timedreceive /* 265 */ .llong .compat_sys_mq_notify .llong .compat_sys_mq_getsetattr - .llong .sys_ni_syscall /* 268 reserved for sys_kexec_load */ + .llong .compat_sys_kexec_load .llong .sys32_add_key .llong .sys32_request_key .llong .compat_sys_keyctl @@ -1227,7 +1398,7 @@ _GLOBAL(sys_call_table) .llong .sys_mq_timedreceive /* 265 */ .llong .sys_mq_notify .llong .sys_mq_getsetattr - .llong .sys_ni_syscall /* 268 reserved for sys_kexec_load */ + .llong .sys_kexec_load .llong .sys_add_key .llong .sys_request_key /* 270 */ .llong .sys_keyctl diff --git a/arch/ppc64/kernel/mpic.c b/arch/ppc64/kernel/mpic.c index 593ea5b82af..e8fbab1df37 100644 --- a/arch/ppc64/kernel/mpic.c +++ b/arch/ppc64/kernel/mpic.c @@ -792,6 +792,35 @@ void mpic_setup_this_cpu(void) #endif /* CONFIG_SMP */ } +/* + * XXX: someone who knows mpic should check this. + * do we need to eoi the ipi here (see xics comments)? + * or can we reset the mpic in the new kernel? + */ +void mpic_teardown_this_cpu(void) +{ + struct mpic *mpic = mpic_primary; + unsigned long flags; + u32 msk = 1 << hard_smp_processor_id(); + unsigned int i; + + BUG_ON(mpic == NULL); + + DBG("%s: teardown_this_cpu(%d)\n", mpic->name, hard_smp_processor_id()); + spin_lock_irqsave(&mpic_lock, flags); + + /* let the mpic know we don't want intrs. */ + for (i = 0; i < mpic->num_sources ; i++) + mpic_irq_write(i, MPIC_IRQ_DESTINATION, + mpic_irq_read(i, MPIC_IRQ_DESTINATION) & ~msk); + + /* Set current processor priority to max */ + mpic_cpu_write(MPIC_CPU_CURRENT_TASK_PRI, 0xf); + + spin_unlock_irqrestore(&mpic_lock, flags); +} + + void mpic_send_ipi(unsigned int ipi_no, unsigned int cpu_mask) { struct mpic *mpic = mpic_primary; diff --git a/arch/ppc64/kernel/mpic.h b/arch/ppc64/kernel/mpic.h index 63e177143ea..99fbbc9a084 100644 --- a/arch/ppc64/kernel/mpic.h +++ b/arch/ppc64/kernel/mpic.h @@ -255,6 +255,9 @@ extern unsigned int mpic_irq_get_priority(unsigned int irq); /* Setup a non-boot CPU */ extern void mpic_setup_this_cpu(void); +/* Clean up for kexec (or cpu offline or ...) */ +extern void mpic_teardown_this_cpu(void); + /* Request IPIs on primary mpic */ extern void mpic_request_ipis(void); diff --git a/arch/ppc64/kernel/pSeries_setup.c b/arch/ppc64/kernel/pSeries_setup.c index f2b41243342..44d9af72d22 100644 --- a/arch/ppc64/kernel/pSeries_setup.c +++ b/arch/ppc64/kernel/pSeries_setup.c @@ -187,14 +187,16 @@ static void __init pSeries_setup_arch(void) { /* Fixup ppc_md depending on the type of interrupt controller */ if (ppc64_interrupt_controller == IC_OPEN_PIC) { - ppc_md.init_IRQ = pSeries_init_mpic; + ppc_md.init_IRQ = pSeries_init_mpic; ppc_md.get_irq = mpic_get_irq; + ppc_md.cpu_irq_down = mpic_teardown_this_cpu; /* Allocate the mpic now, so that find_and_init_phbs() can * fill the ISUs */ pSeries_setup_mpic(); } else { ppc_md.init_IRQ = xics_init_IRQ; ppc_md.get_irq = xics_get_irq; + ppc_md.cpu_irq_down = xics_teardown_cpu; } #ifdef CONFIG_SMP diff --git a/arch/ppc64/kernel/setup.c b/arch/ppc64/kernel/setup.c index 0a47a5ef428..d5e4866e9ac 100644 --- a/arch/ppc64/kernel/setup.c +++ b/arch/ppc64/kernel/setup.c @@ -677,11 +677,16 @@ void __init setup_system(void) DBG(" <- setup_system()\n"); } - -void machine_restart(char *cmd) +/* also used by kexec */ +void machine_shutdown(void) { if (ppc_md.nvram_sync) ppc_md.nvram_sync(); +} + +void machine_restart(char *cmd) +{ + machine_shutdown(); ppc_md.restart(cmd); #ifdef CONFIG_SMP smp_send_stop(); @@ -690,13 +695,11 @@ void machine_restart(char *cmd) local_irq_disable(); while (1) ; } - EXPORT_SYMBOL(machine_restart); - + void machine_power_off(void) { - if (ppc_md.nvram_sync) - ppc_md.nvram_sync(); + machine_shutdown(); ppc_md.power_off(); #ifdef CONFIG_SMP smp_send_stop(); @@ -705,13 +708,11 @@ void machine_power_off(void) local_irq_disable(); while (1) ; } - EXPORT_SYMBOL(machine_power_off); - + void machine_halt(void) { - if (ppc_md.nvram_sync) - ppc_md.nvram_sync(); + machine_shutdown(); ppc_md.halt(); #ifdef CONFIG_SMP smp_send_stop(); @@ -720,7 +721,6 @@ void machine_halt(void) local_irq_disable(); while (1) ; } - EXPORT_SYMBOL(machine_halt); static int ppc64_panic_event(struct notifier_block *this, diff --git a/arch/ppc64/kernel/xics.c b/arch/ppc64/kernel/xics.c index 879f39b90a3..677c4450984 100644 --- a/arch/ppc64/kernel/xics.c +++ b/arch/ppc64/kernel/xics.c @@ -647,6 +647,31 @@ static void xics_set_affinity(unsigned int virq, cpumask_t cpumask) } } +void xics_teardown_cpu(void) +{ + int cpu = smp_processor_id(); + int status; + + ops->cppr_info(cpu, 0x00); + iosync(); + + /* + * we need to EOI the IPI if we got here from kexec down IPI + * + * xics doesn't care if we duplicate an EOI as long as we + * don't EOI and raise priority. + * + * probably need to check all the other interrupts too + * should we be flagging idle loop instead? + * or creating some task to be scheduled? + */ + ops->xirr_info_set(cpu, XICS_IPI); + + status = rtas_set_indicator(GLOBAL_INTERRUPT_QUEUE, + (1UL << interrupt_server_size) - 1 - default_distrib_server, 0); + WARN_ON(status != 0); +} + #ifdef CONFIG_HOTPLUG_CPU /* Interrupts are disabled. */ |