linux-toradex.git/drivers/ata/libata-pmp.c, branch v2.6.27.62

libata: improve EH retry delay handling

2008-07-14T19:59:32+00:00

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 
Signed-off-by: Jeff Garzik

libata: consistently use msecs for time durations

2008-07-14T19:59:32+00:00

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 
Signed-off-by: Jeff Garzik

libata: SRST can't be trusted on PMP sil3726

2008-05-30T16:37:56+00:00

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 
Signed-off-by: Jeff Garzik

libata: make sure PMP notification is turned off during recovery

2008-05-19T21:51:48+00:00

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 
Signed-off-by: Jeff Garzik

libata: increase PMP register access timeout to 3s

2008-05-19T21:51:47+00:00

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 
Signed-off-by: Jeff Garzik

libata: move reset freeze/thaw handling into ata_eh_reset()

2008-05-19T21:51:47+00:00

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 
Signed-off-by: Jeff Garzik

libata: implement PMP helpers

2008-04-17T19:44:25+00:00

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

libata: separate PMP support code from core code

2008-04-17T19:44:25+00:00

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

libata: move PMP SCR access failure during reset to ata_eh_reset()

2008-04-17T19:44:23+00:00

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

libata: clear SError after link resume

2008-04-17T19:44:23+00:00

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