libata lets low level drivers build ata_port_operations table and
register it with libata core layer. This allows low level drivers
high level of flexibility but also burdens them with lots of
boilerplate entries.
This becomes worse for drivers which support related similar
controllers which differ slightly. They share most of the operations
except for a few. However, the driver still needs to list all
operations for each variant. This results in large number of
duplicate entries, which is not only inefficient but also error-prone
as it becomes very difficult to tell what the actual differences are.
This duplicate boilerplates all over the low level drivers also make
updating the core layer exteremely difficult and error-prone. When
compounded with multi-branched development model, it ends up
accumulating inconsistencies over time. Some of those inconsistencies
cause immediate problems and fixed. Others just remain there dormant
making maintenance increasingly difficult.
To rectify the problem, this patch implements ata_port_operations
inheritance. To allow LLDs to easily re-use their own ops tables
overriding only specific methods, this patch implements poor man's
class inheritance. An ops table has ->inherits field which can be set
to any ops table as long as it doesn't create a loop. When the host
is started, the inheritance chain is followed and any operation which
isn't specified is taken from the nearest ancestor which has it
specified. This operation is called finalization and done only once
per an ops table and the LLD doesn't have to do anything special about
it other than making the ops table non-const such that libata can
update it.
libata provides four base ops tables lower drivers can inherit from -
base, sata, pmp, sff and bmdma. To avoid overriding these ops
accidentaly, these ops are declared const and LLDs should always
inherit these instead of using them directly.
After finalization, all the ops table are identical before and after
the patch except for setting .irq_handler to ata_interrupt in drivers
which didn't use to. The .irq_handler doesn't have any actual effect
and the field will soon be removed by later patch.
* sata_sx4 is still using old style EH and currently doesn't take
advantage of ops inheritance.
Signed-off-by: Tejun Heo <htejun@gmail.com>
libata lets low level drivers build scsi_host_template and register it
to the SCSI layer. This allows low level drivers high level of
flexibility but also burdens them with lots of boilerplate entries.
This patch implements SHT initializers which can be used to initialize
all the boilerplate entries in a sht. Three variants of them are
implemented - BASE, BMDMA and NCQ - for different types of drivers.
Note that entries can be overriden by putting individual initializers
after the helper macro.
All sht tables are identical before and after this patch.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Over the time, port info, ops and sht structures developed quite a bit
of inconsistencies. This patch updates drivers.
* Enable/disable_pm callbacks added to all ahci ops tables.
* Every driver for SFF controllers now uses ata_sff_port_start()
instead of ata_port_start() unless the driver has custom
implementation.
* Every driver for SFF controllers now uses ata_pci_default_filter()
unless the driver has custom implementation.
* Removed an odd port_info->sht initialization from ata_piix.c.
Likely a merge byproduct.
* A port which has ATA_FLAG_SATA set doesn't need to set cable_detect
to ata_cable_sata(). Remove it from via and mv port ops.
* Some drivers had unnecessary .max_sectors initialization which is
ignored and was missing .slave_destroy callback. Fixed.
* Removed unnecessary sht initializations port_info's.
* Removed onsolete scsi device suspend/resume callbacks from
pata_bf54x.
* No reason to set ata_pci_default_filter() and bmdma functions for
PIO-only drivers. Remove those callbacks and replace
ata_bmdma_irq_clear with ata_noop_irq_clear.
* pata_platform sets port_start to ata_dummy_ret0. port_start can
just be set to NULL.
* sata_fsl supports NCQ but was missing qc_defer. Fixed.
* pata_rb600_cf implements dummy port_start. Removed.
Signed-off-by: Tejun Heo <htejun@gmail.com>
->irq_clear() is used to clear IRQ bit of a SFF controller and isn't
useful for drivers which don't use libata SFF HSM implementation.
However, it's a required callback and many drivers implement their own
noop version as placeholder. This patch implements ata_noop_irq_clear
and use it to replace those custom placeholders.
Also, SFF drivers which don't support BMDMA don't need to use
ata_bmdma_irq_clear(). It becomes noop if BMDMA address isn't
initialized. Convert them to use ata_noop_irq_clear().
Signed-off-by: Tejun Heo <htejun@gmail.com>
PCI device should be powered up or powered up before its PCI regsiters
are accessed. Although PCI configuration register access is allowed
in D3hot, PCI device is free to reset its status when transiting from
D3hot to D0 causing configuration data to change.
Many libata SFF drivers which use ata_pci_init_one() read and update
configuration registers before calling ata_pci_init_one() which
enables the PCI device. Also, in resume paths, some drivers access
registers without resuming the PCI device.
This patch adds a call to pcim_enable_device() in init path if
register is accessed before calling ata_pci_init_one() and make resume
paths first resume PCI devices, access PCI configuration regiters then
resume ATA host.
While at it...
* cmd640 was strange in that it set ->resume even when CONFIG_PM is
not. This is by-product of minimal build fix. Updated.
* In cs5530, Don't BUG() on reinit failure. Just whine and fail
resume.
Signed-off-by: Tejun Heo <htejun@gmail.com>
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>
Some controllers can't reliably record the initial D2H FIS after SATA
link is brought online for whatever reason. Advanced controllers
which don't have traditional TF register based interface often have
this problem as they don't really have the TF registers to update
while the controller and link are being initialized.
SKIP_D2H_BSY works around the problem by skipping the wait for device
readiness before issuing SRST, so for such controllers libata issues
SRST blindly and hopes for the best.
Now that libata defaults to hardreset, this workaround is no longer
necessary. For controllers which have support for hardreset, SRST is
never issued by itself. It is only issued as follow-up SRST for
device classification and PMP initialization, so there's no need to
wait for it from prereset.
Kill ATA_LFLAG_SKIP_D2H_BSY.
Signed-off-by: Tejun Heo <htejun@gmail.com>
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>
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>
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>
This patch makes the needlessly global ali_atapi_dma static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
According to Broadcom, two chips have their port counts flipped. The proper
count is:
0x241 is 8 ports
0x242 is 4 ports
Reported by Yohei Honda on kernel bz 10424.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Commit 0f436eff54 breaks build on
arch/ppc as it doesn't implement the machine_is() macro.
This fixes it by using CONFIG_PPC_MERGE instead which represents
arch/powerpc only, while CONFIG_PPC is set for both.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
ATAPI DMA just doesn't work reliably on pata_ali. The IDE driver can
do it but for some mysterious reason, pata_ali can't. This patch
disables it by default and makes the driver whine during
initialization. "pata_ali.atapi_dma" parameter is added so that user
can bypass the workaround.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
SAT passthrus don't really fit into ATAPI_MISC class. SAT passthru
commands always transfer multiple of 512 bytes and variable length
response is not allowed. This patch creates a separate category -
ATAPI_PASS_THRU - for these.
This fixes HSM violation on "hdparm -I".
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Uninline atapi_cmd_type(). It doesn't really have to be inline and
more case will be added which need to access unexported libata
variable.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Commit f58229f806 accidentally made
ata_bus_probe() not use reverse order probing. Fix it.
There currently isn't any PATA driver which uses obsolete
ata_bus_probe() path, so this patch is mainly for correctness.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
There have been reported regressions of the SIL 680 driver when using MMIO, so
this makes it only try MMIO on Cell blades where it's known to be necessary
(the host bridge doesn't do PIO on these).
We'll try to find the root problem with MMIO separately.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Make it possible to pass mbus_dram_target_info to the sata_mv
driver via the platform data, make the sata_mv driver program
the window registers based on this data if it is passed in, and
make the Orion platform setup code use this method instead of
programming the SATA mbus window registers by hand.
Signed-off-by: Lennert Buytenhek <buytenh@marvell.com>
Reviewed-by: Tzachi Perelstein <tzachi@marvell.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
At least one report claims that a878539ef9
failed to solve lockups, whereas the old limit-to-32-bit trick worked.
Restore the 32-bit limit, but also leave the 255-sector limit in place,
because we know that's needed as well.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
A Promise SATA controller will signal hotplug events when a hard
reset (COMRESET) is done on a port. These events aren't masked by
the driver, and the unexpected interrupts will cause a sequence
of failed reset attempts util libata's EH finally gives up.
This has not been a common problem so far, but the pending libata
hardreset-by-default changes makes it a critical issue.
The solution is to disable hotplug events before a reset, and to
reenable them afterwards. (Promise's driver does this too.)
This patch adds SATA-specific versions of ->freeze() and ->thaw()
that also disable and enable hotplug events. PATA ports continue
to use the old versions of ->freeze() and ->thaw().
Accesses to the hotplug register must be serialised via host->lock.
We rely on ap->lock == &ap->host->lock and that libata takes this
lock before ->freeze() and ->thaw(). Document this requirement.
The interrupt handler is adjusted so its hotplug register accesses
are inside the region protected by host->lock.
Tested on various chips (SATA300TX4, SATA300TX2plus, SATAII150TX4,
FastTrack TX4000) with various combinations of SATA and PATA disks,
with and without the pending hardreset-by-default changes.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Acked-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
