linux-toradex.git/drivers/ata/libahci.c, branch v4.3.2

Merge branch 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata

2015-06-25T23:49:21+00:00

Pull libata updates from Tejun Heo:

 - a number of libata core changes to better support NCQ TRIM.

 - ahci now supports MSI-X in single IRQ mode to support a new
   controller which doesn't implement MSI or INTX.

 - ahci now supports edge-triggered IRQ mode to support a new controller
   which for some odd reason did edge-triggered IRQ.

 - the usual controller support additions and changes.

* 'for-4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata: (27 commits)
  libata: Do not blacklist Micron M500DC
  ata: ahci_mvebu: add suspend/resume support
  ahci, msix: Fix build error for !PCI_MSI
  ahci: Add support for Cavium's ThunderX host controller
  ahci: Add generic MSI-X support for single interrupts to SATA PCI driver
  libata: finally use __initconst in ata_parse_force_one()
  drivers: ata: add support for Ceva sata host controller
  devicetree:bindings: add devicetree bindings for ceva ahci
  ahci: added support for Freescale AHCI sata
  ahci: Store irq number in struct ahci_host_priv
  ahci: Move interrupt enablement code to a separate function
  Doc: libata: Fix spelling typo found in libata.xml
  ata:sata_nv - Change 1 to true for bool type variable.
  ata: add Broadcom AHCI SATA3 driver for STB chips
  Documentation: devicetree: add Broadcom SATA binding
  libata: Fix regression when the NCQ Send and Receive log page is absent
  ata: hpt366: fix constant cast warning
  ata: ahci_xgene: potential NULL dereference in probe
  ata: ahci_xgene: Add AHCI Support for 2nd HW version of APM X-Gene SoC AHCI SATA Host controller.
  libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch.
  ...

ahci: Store irq number in struct ahci_host_priv

2015-06-03T05:37:49+00:00

Currently, ahci supports only msi and intx. To also support msix the
handling of the irq number need to be changed. The irq number for msix
devices is taken from msi_list instead of pci_dev. Thus, the irq
number of a device needs to be stored in struct ahci_host_priv now.
This allows the host controller to be activated in a generic way.

This change is only intended for ahci drivers. For that reason the irq
number is stored in struct ahci_host_priv used only by ahci drivers.
Thus, the ABI changes only for ahci_host_activate(), but existing ata
drivers (about 50) are unaffected and keep unchanged. All users of
ahci_host_activate() have been updated.

While touching drivers/ata/libahci.c, doing a small code cleanup in
ahci_port_start().

Signed-off-by: Robert Richter 
Signed-off-by: Tejun Heo

libahci: Add support to handle HOST_IRQ_STAT as edge trigger latch.

2015-05-10T15:52:44+00:00

This patch adds the support to handle HOST_IRQ_STAT as edge trigger
latch.

Signed-off-by: Suman Tripathi 
Signed-off-by: Tejun Heo

libahci: Refactoring of ahci_single_irq_intr function.

2015-05-10T15:52:44+00:00

This patch refactors the ahci_single_irq_intr function and also rename
it to ahci_single_level_irq_intr as it handles a level triggered latch.

Signed-off-by: Suman tripathi 
Signed-off-by: Tejun Heo

libata: Add helper to determine when PHY events should be ignored

2015-04-25T20:50:14+00:00

This is a preparation commit that will allow to add other criteria
according to which PHY events should be dropped.

Signed-off-by: Gabriele Mazzotta 
Signed-off-by: Tejun Heo 
Cc: stable@vger.kernel.org

ahci: Use dev_info() to inform about the lack of Device Sleep support

2015-01-09T22:04:12+00:00

According to the Serial ATA AHCI specification, Device Sleep is an
optional feature and as such no errors should be printed if it's
missing. Keep informing users, but use dev_info() instead of dev_err().

Signed-off-by: Gabriele Mazzotta 
Signed-off-by: Tejun Heo

Revert "AHCI: Optimize single IRQ interrupt processing"

2014-10-27T16:02:05+00:00

This reverts commit 18dcf433f3ded61eb140a55e7048ec2fef79e723.
IRQF_ONESHOT was missing from the conversion causing screaming
interrupts problems on some setups and LKP detected measureable drop
in IO performance.  It looks like we'll first need to drop the
threaded IRQ handling first before splitting locking.

Signed-off-by: Tejun Heo 
Cc: Alexander Gordeev 
Reported-by: kernel test robot 
Reported-by: Marc Zyngier 
Link: http://lkml.kernel.org/g/20141027021651.GF27038@yliu-dev.sh.intel.com
Link: http://lkml.kernel.org/g/1414082970-20775-1-git-send-email-marc.zyngier@arm.com

Revert "AHCI: Do not acquire ata_host::lock from single IRQ handler"

2014-10-27T16:00:01+00:00

This reverts commit 33fb0d01ce60fe4c0c12c4f0c134c5cdb818ac5a.

18dcf433f3de ("AHCI: Optimize single IRQ interrupt processing") is
scheduled to be reverted.  This is an optimization dependent on the
mentioned commit.  Revert it first.

Signed-off-by: Tejun Heo

AHCI: Do not acquire ata_host::lock from single IRQ handler

2014-10-06T15:43:36+00:00

There is no need to acquire ata_host::lock spinlock from
hardware context single IRQ interrupt handler since the
handler does not access host data that could be altered
by concurrent processors.

Signed-off-by: Alexander Gordeev 
Signed-off-by: Tejun Heo 
Cc: linux-ide@vger.kernel.org

AHCI: Optimize single IRQ interrupt processing

2014-10-06T15:43:36+00:00

Split interrupt service routine into hardware context handler
and threaded context handler. That allows to protect ports with
individual locks rather than with a single host-wide lock and
move port interrupts handling out of the hardware interrupt
context.

Testing was done by transferring 8GB on two hard drives in
parallel using command 'dd if=/dev/sd{a,b} of=/dev/null'. With
lock_stat statistics I measured access times to ata_host::lock
spinlock (since interrupt handler code is fully embraced with
this lock). The average lock's holdtime decreased eight times
while average waittime decreased two times.

Both before and after the change the transfer time is the same,
while 'perf record -e cycles:k ...' shows 1%-4% CPU time spent
in ahci_single_irq_intr() routine before the update and not even
sampled/shown ahci_single_irq_intr() after the update.

Signed-off-by: Alexander Gordeev 
Signed-off-by: Tejun Heo 
Cc: linux-ide@vger.kernel.org