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path: root/drivers/ata/libata-pmp.c
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2008-07-14libata: improve EH retry delay handlingTejun Heo
EH retries were delayed by 5 seconds to ensure that resets don't occur back-to-back. However, this 5 second delay is superflous or excessive in many cases. For example, after IDENTIFY times out, there's no reason to wait five more seconds before retrying. This patch adds ehc->last_reset timestamp and record the timestamp for the last reset trial or success and uses it to space resets by ATA_EH_RESET_COOL_DOWN which is 5 secs and removes unconditional 5 sec sleeps. As this change makes inter-try waits often shorter and they're redundant in nature, this patch also removes the "retrying..." messages. While at it, convert explicit rounding up division to DIV_ROUND_UP(). This change speeds up EH in many cases w/o sacrificing robustness. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-07-14libata: consistently use msecs for time durationsTejun Heo
libata has been using mix of jiffies and msecs for time druations. This is getting confusing. As writing sub HZ values in jiffies is PITA and msecs_to_jiffies() can't be used as initializer, unify unit for all time durations to msecs. So, durations are in msecs and deadlines are in jiffies. ata_deadline() is added to compute deadline from a start time and duration in msecs. While at it, drop now superflous _msec suffix from arguments and rename @timeout to @deadline if it represents a fixed point in time rather than duration. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-30libata: SRST can't be trusted on PMP sil3726Tejun Heo
As in sil4726, SRST can't be trusted on sil3726 causing detection problems under certain configuraitons. I thought it was from the Config Disk device but apparently not. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-19libata: make sure PMP notification is turned off during recoveryTejun Heo
PMP notification during reset can make some controllers fail reset processing and needs to be turned off during resets. PMP attach and full-revalidation path did this via sata_pmp_configure() but the quick revalidation wasn't. Move the notification disable code right above fan-out port recovery so that it's always turned off. This fixes obscure reset failures. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-19libata: increase PMP register access timeout to 3sTejun Heo
This timeout was set low because previously PMP register access was done via polling and register access timeouts could stack up. This is no longer the case. One timeout will make all following accesses fail immediately. In rare cases both marvell and SIMG PMPs need almost a second. Bump it to 3s. While at it, rename it to SATA_PMP_RW_TIMEOUT. It's not specific to SCR access. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-05-19libata: move reset freeze/thaw handling into ata_eh_reset()Tejun Heo
Previously reset freeze/thaw handling lived outside of ata_eh_reset() mainly because the original PMP reset code needed the port frozen while resetting all the fan-out ports, which is no longer the case. This patch moves freeze/thaw handling into ata_eh_reset(). @prereset() and @postreset() are now called w/o freezing the port although @prereset() an be called frozen if the port is frozen prior to entering ata_eh_reset(). This makes code simpler and will help removing hotplug event related races. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2008-04-17libata: implement PMP helpersTejun Heo
Implement helpers to test whether PMP is supported, attached and determine pmp number to use when issuing SRST to a link. While at it, move ata_is_host_link() so that it's together with the two new PMP helpers. This change simplifies LLDs and helps making PMP support optional. Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17libata: separate PMP support code from core codeTejun Heo
Most of PMP support code is already in libata-pmp.c. All that are in libata-core.c are sata_pmp_port_ops and EXPORTs. Move them to libata-pmp.c. Also, collect PMP related prototypes and declarations in header files and move them right above of SFF stuff. This change is to make PMP support optional. Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17libata: move PMP SCR access failure during reset to ata_eh_reset()Tejun Heo
If PMP fan-out reset fails and SCR isn't accessible, PMP should be reset. This used to be tested by sata_pmp_std_hardreset() and communicated to EH by -ERESTART. However, this logic is generic and doesn't really have much to do with specific hardreset implementation. This patch moves SCR access failure detection logic to ata_eh_reset() where it belongs. As this makes sata_pmp_std_hardreset() identical to sata_std_hardreset(), the function is killed and replaced with the standard method. Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17libata: clear SError after link resumeTejun Heo
SError used to be cleared in ->postreset. This has small hotplug race condition. If a device is plugged in after reset is complete but postreset hasn't run yet, its hotplug event gets lost when SError is cleared. This patch makes sata_link_resume() clear SError. This kills the race condition and makes a lot of sense as some PMP and host PHYs don't work properly without SError cleared. This change makes sata_pmp_std_{pre|post}_reset()'s unnecessary as they become identical to ata_std counterparts. It also simplifies sata_pmp_hardreset() and ahci_vt8251_hardreset(). Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17libata: move generic hardreset code from sata_sff_hardreset() to ↵Tejun Heo
sata_link_hardreset() sata_sff_hardreset() contains link readiness wait logic which isn't SFF specific. Move that part into sata_link_hardreset(), which now takes two more parameters - @online and @check_ready. Both are optional. The former is out parameter for link onlineness after reset. The latter is used to wait for link readiness after hardreset. Users of sata_link_hardreset() is updated to use new funtionality and ahci_hardreset() is updated to use sata_link_hardreset() instead of sata_sff_hardreset(). This doesn't really cause any behavior change. Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17libata: make reset related methods proper port operationsTejun Heo
Currently reset methods are not specified directly in the ata_port_operations table. If a LLD wants to use custom reset methods, it should construct and use a error_handler which uses those reset methods. It's done this way for two reasons. First, the ops table already contained too many methods and adding four more of them would noticeably increase the amount of necessary boilerplate code all over low level drivers. Second, as ->error_handler uses those reset methods, it can get confusing. ie. By overriding ->error_handler, those reset ops can be made useless making layering a bit hazy. Now that ops table uses inheritance, the first problem doesn't exist anymore. The second isn't completely solved but is relieved by providing default values - most drivers can just override what it has implemented and don't have to concern itself about higher level callbacks. In fact, there currently is no driver which actually modifies error handling behavior. Drivers which override ->error_handler just wraps the standard error handler only to prepare the controller for EH. I don't think making ops layering strict has any noticeable benefit. This patch makes ->prereset, ->softreset, ->hardreset, ->postreset and their PMP counterparts propoer ops. Default ops are provided in the base ops tables and drivers are converted to override individual reset methods instead of creating custom error_handler. * ata_std_error_handler() doesn't use sata_std_hardreset() if SCRs aren't accessible. sata_promise doesn't need to use separate error_handlers for PATA and SATA anymore. * softreset is broken for sata_inic162x and sata_sx4. As libata now always prefers hardreset, this doesn't really matter but the ops are forced to NULL using ATA_OP_NULL for documentation purpose. * pata_hpt374 needs to use different prereset for the first and second PCI functions. This used to be done by branching from hpt374_error_handler(). The proper way to do this is to use separate ops and port_info tables for each function. Converted. Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17libata: kill ata_ehi_schedule_probe()Tejun Heo
ata_ehi_schedule_probe() was created to hide details of link-resuming reset magic. Now that all the softreset workarounds are gone, scheduling probe is very simple - set probe_mask and request RESET. Kill ata_ehi_schedule_probe() and open code it. This also increases consistency as ata_ehi_schedule_probe() couldn't cover individual device probings so they were open-coded even when the helper existed. While at it, define ATA_ALL_DEVICES as mask of all possible devices on a link and always use it when requesting probe on link level for simplicity and consistency. Setting extra bits in the probe_mask doesn't hurt anybody. Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17libata: kill ATA_EHI_RESUME_LINKTejun Heo
ATA_EHI_RESUME_LINK has two functions - promote reset to hardreset if ATA_LFLAG_HRST_TO_RESUME is set and preventing EH from shortcutting reset action when probing is requested. The former is gone now and the latter can easily be achieved by making EH to perform at least one reset if reset is requested, which also makes more sense than depending on RESUME_LINK flag. As ATA_EHI_RESUME_LINK was the only EHI reset modifier, this also kills reset modifier handling. Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17libata: kill ATA_LFLAG_HRST_TO_RESUMETejun Heo
Now that hardreset is the preferred method of resetting, there's no need for ATA_LFLAG_HRST_TO_RESUME flag. Kill it. Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-04-17libata: prefer hardresetTejun Heo
When both soft and hard resets are available, libata preferred softreset till now. The logic behind it was to be softer to devices; however, this doesn't really help much. Rationales for the change: * BIOS may freeze lock certain things during boot and softreset can't unlock those. This by itself is okay but during operation PHY event or other error conditions can trigger hardreset and the device may end up with different configuration. For example, after a hardreset, previously unlockable HPA can be unlocked resulting in different device size and thus revalidation failure. Similar condition can occur during or after resume. * Certain ATAPI devices require hardreset to recover after certain error conditions. On PATA, this is done by issuing the DEVICE RESET command. On SATA, COMRESET has equivalent effect. The problem is that DEVICE RESET needs its own execution protocol. For SFF controllers with bare TF access, it can be easily implemented but more advanced controllers (e.g. ahci and sata_sil24) require specialized implementations. Simply using hardreset solves the problem nicely. * COMRESET initialization sequence is the norm in SATA land and many SATA devices don't work properly if only SRST is used. For example, some PMPs behave this way and libata works around by always issuing hardreset if the host supports PMP. Like the above example, libata has developed a number of mechanisms aiming to promote softreset to hardreset if softreset is not going to work. This approach is time consuming and error prone. Also, note that, dependingon how you read the specs, it could be argued that PMP fan-out ports require COMRESET to start operation. In fact, all the PMPs on the market except one don't work properly if COMRESET is not issued to fan-out ports after PMP reset. * COMRESET is an integral part of SATA connection and any working device should be able to handle COMRESET properly. After all, it's the way to signal hardreset during reboot. This is the most used and recommended (at least by the ahci spec) method of resetting devices. So, this patch makes libata prefer hardreset over softreset by making the following changes. * Rename ATA_EH_RESET_MASK to ATA_EH_RESET and use it whereever ATA_EH_{SOFT|HARD}RESET used to be used. ATA_EH_{SOFT|HARD}RESET is now only used to tell prereset whether soft or hard reset will be issued. * Strip out now unneeded promote-to-hardreset logics from ata_eh_reset(), ata_std_prereset(), sata_pmp_std_prereset() and other places. Signed-off-by: Tejun Heo <htejun@gmail.com>
2008-02-24libata-pmp: clear hob for pmp register accessesMark Lord
>> Mark Lord wrote: >>> Tejun, I've added PMP to sata_mv, and am now trying to get it >>> to work with a Marvell PM attached. >>> >>> And the behaviour I see is very bizarre. >>> >>> After hard+soft resets, the PM signature is found, >>> and libata interrogates the PM registers. >>> >>> It successfully reads register 0, and then register 1. >>> But all subsequent registers read out (incorrectly) as zeros. ... This behavior has been confirmed by Marvell with a SATA analyzer. The Marvell port-multiplier apparently likes to see clean HOB information when accessing PMP registers. Since sata_mv uses PIO shadow register access, this doesn't happen automatically, as it might in a more purely FIS-based driver (eg. ahci). One way to fix this is to flag these commands with ATA_TFLAG_LBA48, forcing libata to write out the HOB fields with known (zero) values. Signed-off-by: Saeed Bishara <saeed@marvell.com> Acked-by: Mark Lord <mlord@pobox.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-01-10libata-pmp: 4726 hates SRSTTejun Heo
4726 hates SRST even on non-config ports. Don't use it. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-10-12libata: use ata_exec_internal() for PMP register accessTejun Heo
PMP registers used to be accessed with dedicated accessors ->pmp_read and ->pmp_write. During reset, those callbacks are called with the port frozen so they should be able to run without depending on interrupt delivery. To achieve this, they were implemented polling. However, as resetting the host port makes the PMP to isolate fan-out ports until SError.X is cleared, resetting fan-out ports while port is frozen doesn't buy much additional safety. This patch updates libata PMP support such that PMP registers are accessed using regular ata_exec_internal() mechanism and kills ->pmp_read/write() callbacks. The following changes are made. * PMP access helpers - sata_pmp_read_init_tf(), sata_pmp_read_val(), sata_pmp_write_init_tf() are folded into sata_pmp_read/write() which are now standalone PMP register access functions. * sata_pmp_read/write() returns err_mask instead of rc. This is consistent with other functions which issue internal commands and allows more detailed error reporting. * ahci interrupt handler is modified to ignore BAD_PMP and spurious/illegal completion IRQs while reset is in progress. These conditions are expected during reset. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-10-12libata-pmp: implement qc_defer for command switching PMP supportTejun Heo
Implement sata_pmp_qc_defer_cmd_switch() - standard qc_defer for command switching PMP support. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-10-12libata-pmp: extend ACPI support to cover PMPTejun Heo
Extend ata_acpi_associate_sata_port() such that it can handle PMP and call it when PMP is attached and detached. Build breakage when !CONFIG_ATA_ACPI was spotted and fixed by Petr Vandrovec. Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Petr Vandrovec <petr@vandrovec.name> Signed-off-by: Jeff Garzik <jeff@garzik.org>
2007-10-12libata-pmp: implement Port Multiplier supportTejun Heo
Implement Port Multiplier support. To support PMP, a LLDD has to supply ops->pmp_read() and pmp_write(). If non-null, ->pmp_attach and ->pmp_detach are called on PMP attach and detach, respectively. ->pmp_read/write() can be called while the port is frozen, so they must be implemented by polling. This patch supplies several helpers to ease ->pmp_read/write() implementation. Also, irq_handler and error_handler must be PMP aware. Most of PMP aware EH can be done by calling ata_pmp_do_eh() with appropriate methods. PMP EH uses separate set of reset methods and this patch implements standard prereset, hardreset and postreset methods. This patch only implements PMP support. The next patch will integrate PMP into the reset of libata and thus enable PMP support. Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>