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We must disable the DMA engine before accessing taskfile registers.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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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>
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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>
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No functional changes in this patch.
Signed-off-by: Erik Inge Bolsø <knan-lkml@anduin.net>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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SFF functions have confusing names. Some have sff prefix, some have
bmdma, some std, some pci and some none. Unify the naming by...
* SFF functions which are common to both BMDMA and non-BMDMA are
prefixed with ata_sff_.
* SFF functions which are specific to BMDMA are prefixed with
ata_bmdma_.
* SFF functions which are specific to PCI but apply to both BMDMA and
non-BMDMA are prefixed with ata_pci_sff_.
* SFF functions which are specific to PCI and BMDMA are prefixed with
ata_pci_bmdma_.
* Drop generic prefixes from LLD specific routines. For example,
bfin_std_dev_select -> bfin_dev_select.
The following renames are noteworthy.
ata_qc_issue_prot() -> ata_sff_qc_issue()
ata_pci_default_filter() -> ata_bmdma_mode_filter()
ata_dev_try_classify() -> ata_sff_dev_classify()
This rename is in preparation of separating SFF support out of libata
core layer. This patch strictly renames functions and doesn't
introduce any behavior difference.
Signed-off-by: Tejun Heo <htejun@gmail.com>
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ata_chk_status() just calls ops->check_status and it only adds
confusion with other status functions. Kill it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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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>
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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>
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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>
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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>
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Implement protocol tests - ata_is_atapi(), ata_is_nodata(),
ata_is_pio(), ata_is_dma(), ata_is_ncq() and ata_is_data() and use
them to replace is_atapi_taskfile() and hard coded protocol tests.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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link->eh_info.serror is used to cache SError for controllers which
need it cleared from interrupt handler to clear IRQ. It also should
be cleared after reset just like SError itself.
Make ata_std_postreset() clear link->eh_info.serror too and update
sata_sil such that it doesn't care about bookkeeping the value.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Interestingly, sata_sil raises spurious interrupts if it's coupled
with Sil SATA_PATA bridge. Currently, sata_sil interrupt handler is
strict about spurious interrupts and freezes the port when it occurs.
This patch makes it more forgiving.
* On SATA PHY event interrupt, serror value is checked to see whether
it really is PHYRDY CHG event. If not, SATA PHY event interrupt is
ignored.
* If ATA interrupt occurs while no command is in progress, it's
cleared and ignored.
This fixes bugzilla bug 9505.
http://bugzilla.kernel.org/show_bug.cgi?id=9505
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
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Currently, port configuration reporting has the following problems.
* iomapped address is reported instead of raw address
* report contains irrelevant fields or lacks necessary fields for
non-SFF controllers.
* host->irq/irq2 are there just for reporting and hacky.
This patch implements and uses ata_port_desc() and
ata_port_pbar_desc(). ata_port_desc() is almost identical to
ata_ehi_push_desc() except that it takes @ap instead of @ehi, has no
locking requirement, can only be used during host initialization and "
" is used as separator instead of ", ". ata_port_pbar_desc() is a
helper to ease reporting of a PCI BAR or an offsetted address into it.
LLD pushes whatever description it wants using the above two
functions. The accumulated description is printed on host
registration after "[S/P]ATA max MAX_XFERMODE ".
SFF init helpers and ata_host_activate() automatically add
descriptions for addresses and irq respectively, so only LLDs which
isn't standard SFF need to add custom descriptions. In many cases,
such controllers need to report different things anyway.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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It was always set to ata_port_disable(). Removed the hook, and replaced
the very few ap->ops->port_disable() callsites with direct calls to
ata_port_disable().
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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* ->irq_ack() is redundant to what the irq handler already
performs... chk-status + irq-clear. Furthermore, it is only
called in one place, when screaming-irq-debugging is enabled,
so we don't want to bother with a hook just for that.
* ata_dummy_irq_on() is only ever used in drivers that have
no callpath reaching ->irq_on(). Remove .irq_on hook from
those drivers, and the now-unused ata_dummy_irq_on()
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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HRST_TO_RESUME and SKIP_D2H_BSY are link attributes. Move them to
ata_link->flags. This will allow host and PMP links to have different
attributes. ata_port_info->link_flags is added and used by LLDs to
specify these flags during initialization.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Make the following functions deal with ata_link instead of ata_port.
* ata_set_mode()
* ata_eh_autopsy() and related functions
* ata_eh_report() and related functions
* suspend/resume related functions
* ata_eh_recover() and related functions
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Multiple links and different number of devices per link should be
considered to iterate over links and devices. This patch implements
and uses link and device iterators - ata_port_for_each_link() and
ata_link_for_each_dev() - and ata_link_max_devices().
This change makes a lot of functions iterate over only possible
devices instead of from dev 0 to dev ATA_MAX_DEVICES. All such
changes have been examined and nothing should be broken.
While at it, add a separating comment before device helpers to
distinguish them better from link helpers and others.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Introduce ata_link. It abstracts PHY and sits between ata_port and
ata_device. This new level of abstraction is necessary to support
SATA Port Multiplier, which basically adds a bunch of links (PHYs) to
a ATA host port. Fields related to command execution, spd_limit and
EH are per-link and thus moved to ata_link.
This patch only defines the host link. Multiple link handling will be
added later. Also, a lot of ap->link derefences are added but many of
them will be removed as each part is converted to deal directly with
ata_link instead of ata_port.
This patch introduces no behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Bump the versions for drivers that were modified, but had not already
had a version number bump.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Convert ->scr_read/write callbacks to return error code to better
indicate failure. This will help handling of SCR_NOTIFICATION.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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The ATA_UDMAx masks are self-documenting, and far better than manually
writing in the hex mask.
Note that pata_it8213 mask differed from the comment. Added a FIXME there.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Make the register offset table more maintainable.
From the 'sii-lbt' branch, which enables the LBT chip feature.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Reimplement suspend/resume support using sdev->manage_start_stop.
* Device suspend/resume is now SCSI layer's responsibility and the
code is simplified a lot.
* DPM is dropped. This also simplifies code a lot. Suspend/resume
status is port-wide now.
* ata_scsi_device_suspend/resume() and ata_dev_ready() removed.
* Resume now has to wait for disk to spin up before proceeding. I
couldn't find easy way out as libata is in EH waiting for the
disk to be ready and sd is waiting for EH to complete to issue
START_STOP.
* sdev->manage_start_stop is set to 1 in ata_scsi_slave_config().
This fixes spindown on shutdown and suspend-to-disk.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Convert ahci, sata_sil, sata_sil24, sata_svw, sata_qstor, sata_mv,
sata_sx4, sata_vsc and sata_inic162x to new init model.
Now that host and ap are available during intialization, functions are
converted to take either host or ap instead of low level parameters
which were inevitable for functions shared between init and other
paths. This simplifies code quite a bit.
* init_one()'s now follow more consistent init order
* ahci_setup_port() and ahci_host_init() collapsed into
ahci_init_one() for init order consistency
* sata_vsc uses port_info instead of setting fields manually
* in sata_svw, k2_board_info converted to port_info (info is now in
port flags). port number is honored now.
Tested on ICH7/8 AHCI, jmb360, sil3112, 3114, 3124 and 3132.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Now that we have ata_do_set_mode() available for drivers to use we don't
actually need ->post_set_mode() as the driver can wrap set_mode nicely
and do stuff before or after (eg PCMCIA needs before), so we can kill off
a method in all the structs
While I was at it I added kernel-doc to the function involved.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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It used to be impossible to get from ata_device to ata_port but that is
no longer true. Various methods have been cleaned up over time but
dev_config still takes both and most users don't need both anyway. Tidy
this one up
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Add missing #ifdef CONFIG_PM conditionals around all PM related parts
in libata LLDs.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Bump versions based on changes submitted during 2.6.21 merge window.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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sata_sil used to trigger HSM error if IRQ occurs during polling
command. This didn't matter because polling wasn't used in sata_sil.
However, as of 2.6.20, all IDENTIFYs are performed by polling and
device detection sometimes fails due to spurious IRQ. This patch
makes sata_sil ignore and clear spurious IRQ while executing commands
by polling.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Fix sparse warnings in SATA:
drivers/ata/sata_sil.c:342:9: warning: Using plain integer as NULL pointer
drivers/ata/sata_mv.c:2056:55: warning: Using plain integer as NULL pointer
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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This patch is against each libata driver.
Two IRQ calls are added in ata_port_operations.
- irq_on() is used to enable interrupts.
- irq_ack() is used to acknowledge a device interrupt.
In most drivers, ata_irq_on() and ata_irq_ack() are used for
irq_on and irq_ack respectively.
In some drivers (ex: ahci, sata_sil24) which cannot use them
as is, ata_dummy_irq_on() and ata_dummy_irq_ack() are used.
Signed-off-by: Kou Ishizaki <kou.ishizaki@toshiba.co.jp>
Signed-off-by: Akira Iguchi <akira2.iguchi@toshiba.co.jp>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Convert libata core layer and LLDs to use iomap.
* managed iomap is used. Pointer to pcim_iomap_table() is cached at
host->iomap and used through out LLDs. This basically replaces
host->mmio_base.
* if possible, pcim_iomap_regions() is used
Most iomap operation conversions are taken from Jeff Garzik
<jgarzik@pobox.com>'s iomap branch.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Update libata LLDs to use devres. Core layer is already converted to
support managed LLDs. This patch simplifies initialization and fixes
many resource related bugs in init failure and detach path. For
example, all converted drivers now handle ata_device_add() failure
gracefully without excessive resource rollback code.
As most resources are released automatically on driver detach, many
drivers don't need or can do with much simpler ->{port|host}_stop().
In general, stop callbacks are need iff port or host needs to be given
commands to shut it down. Note that freezing is enough in many cases
and ports are automatically frozen before being detached.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Handle pci_enable_device() failure while resuming. This patch kills
the "ignoring return value of 'pci_enable_device'" warning message and
propagates __must_check through ata_pci_device_do_resume().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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* Kill _OFS suffixes in ATA_ID_{SERNO|FW_REV|PROD}_OFS for consistency
with other ATA_ID_* constants.
* Kill ATA_SERNO_LEN
* Add and use ATA_ID_SERNO_LEN, ATA_ID_FW_REV_LEN and ATA_ID_PROD_LEN.
This change also makes ata_device_blacklisted() use proper length
for fwrev.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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For certain errors, interrupt handler alter BMDMA host status before
entering EH (clears active and intr). Thus altered BMDMA host status
value is recorded by BMDMA EH and reported to user. Move BMDMA host
status recording from EH to interrupt handler.
Signed-off-by: Tejun Heo <htejun@gmail.com>
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Implement ehi flag ATA_EHI_PRINTINFO. This flag is set when device
configuration needs to print out device info. This used to be handled
by @print_info argument to ata_dev_configure() but LLDs also need to
know about it in ->dev_config() callback.
This patch replaces @print_info w/ ATA_EHI_PRINTINFO and make sata_sil
print workaround messages only on the initial configuration.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
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