The current LPM implementation has the following issues.
* Operation order isn't well thought-out. e.g. HIPM should be
configured after IPM in SControl is properly configured. Not the
other way around.
* Suspend/resume paths call ata_lpm_enable/disable() which must only
be called from EH context directly. Also, ata_lpm_enable/disable()
were called whether LPM was in use or not.
* Implementation is per-port when it should be per-link. As a result,
it can't be used for controllers with slave links or PMP.
* LPM state isn't managed consistently. After a link reset for
whatever reason including suspend/resume the actual LPM state would
be reset leaving ap->lpm_policy inconsistent.
* Generic/driver-specific logic boundary isn't clear. Currently,
libahci has to mangle stuff which libata EH proper should be
handling. This makes the implementation unnecessarily complex and
fragile.
* Tied to ALPM. Doesn't consider DIPM only cases and doesn't check
whether the device allows HIPM.
* Error handling isn't implemented.
Given the extent of mismatch with the rest of libata, I don't think
trying to fix it piecewise makes much sense. This patch reimplements
LPM support.
* The new implementation is per-link. The target policy is still
port-wide (ap->target_lpm_policy) but all the mechanisms and states
are per-link and integrate well with the rest of link abstraction
and can work with slave and PMP links.
* Core EH has proper control of LPM state. LPM state is reconfigured
when and only when reconfiguration is necessary. It makes sure that
LPM state is reset when probing for new device on the link.
Controller agnostic logic is now implemented in libata EH proper and
driver implementation only has to deal with controller specifics.
* Proper error handling. LPM config failure is attributed to the
device on the link and LPM is disabled for the link if it fails
repeatedly.
* ops->enable/disable_pm() are replaced with single ops->set_lpm()
which takes @policy and @hints. This simplifies driver specific
implementation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Link power management related symbols are in confusing state w/ mixed
usages of lpm, ipm and pm. This patch cleans up lpm related symbols
and sysfs show/store functions as follows.
* lpm states - NOT_AVAILABLE, MIN_POWER, MAX_PERFORMANCE and
MEDIUM_POWER are renamed to ATA_LPM_UNKNOWN and
ATA_LPM_{MIN|MAX|MED}_POWER.
* Pre/postfixes are unified to lpm.
* sysfs show/store functions for link_power_management_policy were
curiously named get/put and unnecessarily complex. Renamed to
show/store and simplified.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
libata depends on scsi_host_template for module reference counting and
sht's should be owned by each low level driver. During libahci split,
the sht was left with libahci.ko leaving the actual low level drivers
not reference counted. This made ahci and ahci_platform always
unloadable even while they're being actively used.
Fix it by defining AHCI_SHT() macro in ahci.h and defining a sht for
each low level ahci driver.
stable: only applicable to 2.6.35.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Pedro Francisco <pedrogfrancisco@gmail.com>
Tested-by: Michael Tokarev <mjt@tls.msk.ru>
Cc: stable@kernel.org
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
The driver is using platform_driver_probe() during initialization,
so ahci_driver.probe hook is never used.
But it causes the following (harmless, luckily) section mismatch:
WARNING: vmlinux.o(.data+0x2fb20): Section mismatch in reference
from the variable ahci_driver to the function .init.text:ahci_probe()
This patch removes the ahci_driver.probe assignment, thus fixes
the warning.
p.s. Note that there's another patch[1] from Rene Bolldorf that
tried to solve the same issue by __refdata annotation. __refdata
says that this reference is actually OK, but in fact it is not OK,
because dereferencing .probe() will cause problems. So the proper
fix is to remove the assignment.
[1] http://kerneltrap.org/mailarchive/linux-kernel/2010/3/18/4549547
Signed-off-by: Anton Vorontsov <avorontsov@mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Some AHCI implementations may use Vendor Specific HBA[A0h, FFh]
and/or Port[70h, 7Fh] registers to 'prepare' for initialization.
For that, the platform needs memory mapped address of AHCI registers.
This patch adds the 'mmio' argument and reorders the call to
platform init function.
Signed-off-by: Jassi Brar <jassi.brar@samsung.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Implicit slab.h inclusion via percpu.h is about to go away. Make sure
gfp.h or slab.h is included as necessary.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This can be used for AHCI-compatible interfaces implemented inside
System-On-Chip solutions, or AHCI devices connected via localbus.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
