host->ports[] always contain pointers to valid port structures since
a "dummy port" structure is used in case if there is no physical port.

This patch takes care of two entries from Dan's list:

drivers/ata/sata_sil.c +535 sil_interrupt(13) warning: variable derefenced before check 'ap'
drivers/ata/sata_mv.c +2517 mv_unexpected_intr(6) warning: variable derefenced before check 'ap'

and of another needless NULL pointer check in pata_octeon_cf.c.

Reported-by: Dan Carpenter <error27@gmail.com>
Cc: corbet@lwn.net
Cc: eteo@redhat.com
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

32-bit PIO seems to work fine on sata_sil hardware (tested on SiI3114) and is
listed as OK in the Silicon Image datasheets. Enable it.

Signed-off-by: Robert Hancock <hancockrwd@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

No functional changes in this patch.

Signed-off-by: Erik Inge Bolsø <knan-lkml@anduin.net>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

I tried compiling 2.6.29-rc1 and 2.6.29-rc3 with libata debugging enabled
and got the following error:

  CC [M]  drivers/ata/sata_sil.o
drivers/ata/sata_sil.c: In function 'sil_fill_sg':
drivers/ata/sata_sil.c:327: error: 'pi' undeclared (first use in this function)
drivers/ata/sata_sil.c:327: error: (Each undeclared identifier is reported only once
drivers/ata/sata_sil.c:327: error: for each function it appears in.)
make[2]: *** [drivers/ata/sata_sil.o] Error 1
make[1]: *** [drivers/ata] Error 2
make: *** [drivers] Error 2

include/linux/libata.h has the following enabled:

#define ATA_DEBUG
#define ATA_VERBOSE_DEBUG
#define ATA_IRQ_TRAP

This fixes the compilation.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

Commit e57db7b (SATA Sil: Blacklist system that spins off disks during ACPI power off)
 breaks build like the following, in both cases when CONFIG_DMI set or not.

        drivers/ata/sata_sil.c: In function 'sil_broken_system_poweroff':
        drivers/ata/sata_sil.c:713: error: implicit declaration of function 'dmi_first_match'
        drivers/ata/sata_sil.c:713: warning: initialization makes pointer from integer without a cast

  sata_sil.c should include dmi.h

Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Some notebooks from HP have the problem that their BIOSes attempt to
spin down hard drives before entering ACPI system states S4 and S5.
This leads to a yo-yo effect during system power-off shutdown and the
last phase of hibernation when the disk is first spun down by the
kernel and then almost immediately turned on and off by the BIOS.
This, in turn, may result in shortening the disk's life times.

To prevent this from happening we can blacklist the affected systems
using DMI information.

Blacklist HP nx6325 that uses the sata_sil driver.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

This implements support for the Large Block Transfer feature found in Silicon
Image 311x controllers. This allows transferring bigger contiguous chunks of
data from system memory and avoids the 64KB boundary restriction of standard
SFF controllers.

This is based on a patch from Jeff Garzik (from the sii-lbt branch of
libata-dev) but includes a few bug fixes: Since the bmdma2 register does not
implement the status bits, the original bmdma register must be used except
where the bmdma2 register is required. As well the DMA boundary should be
31-bit instead of 32-bit since the top bit of the length field is still
required for the PRD end-of-table flag.

Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

There currently are the following looping constructs.

* __ata_port_for_each_link() for all available links
* ata_port_for_each_link() for edge links
* ata_link_for_each_dev() for all devices
* ata_link_for_each_dev_reverse() for all devices in reverse order

Now there's a need for looping construct which is similar to
__ata_port_for_each_link() but iterates over PMP links before the host
link.  Instead of adding another one with long name, do the following
cleanup.

* Implement and export ata_link_next() and ata_dev_next() which take
  @mode parameter and can be used to build custom loop.
* Implement ata_for_each_link() and ata_for_each_dev() which take
  looping mode explicitly.

The following iteration modes are implemented.

* ATA_LITER_EDGE		: loop over edge links
* ATA_LITER_HOST_FIRST		: loop over all links, host link first
* ATA_LITER_PMP_FIRST		: loop over all links, PMP links first

* ATA_DITER_ENABLED		: loop over enabled devices
* ATA_DITER_ENABLED_REVERSE	: loop over enabled devices in reverse order
* ATA_DITER_ALL			: loop over all devices
* ATA_DITER_ALL_REVERSE		: loop over all devices in reverse order

This change removes exlicit device enabledness checks from many loops
and makes it clear which ones are iterated over in which direction.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

Logically, SCR access ops should take @link; however, there was no
compelling reason to convert all SCR access ops when adding @link
abstraction as there's one-to-one mapping between a port and a non-PMP
link.  However, that assumption won't hold anymore with the scheduled
addition of slave link.

Make SCR access ops per-link.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

Add sff_ prefix to SFF specific port ops.

This rename is in preparation of separating SFF support out of libata
core layer.  This patch strictly renames ops and doesn't introduce any
behavior difference.

Signed-off-by: Tejun Heo <htejun@gmail.com>