Dave Müller sent a diff for the pata_oldpiix that highlighted a problem
where a lot of the ATA drivers assume dma_mode == 0 means "no DMA" while
the core code uses 0xFF.
This turns out to have other consequences such as code doing >= XFER_UDMA_0
also catching 0xFF as UDMAlots. Fortunately it doesn't generally affect
set_dma_mode, although some drivers call back into their own set mode code
from other points.
Having been through the drivers I've added helpers for using_udma/using_mwdma
dma_enabled so that people don't open code ranges that may change (eg if UDMA8
appears somewhere)
Thanks to David for the initial bits
[and added fix for pata_oldpiix from and signed-off-by Dave Mueller
<dave.mueller@gmx.ch> -jg]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Save SControl during probing and restore it on detach. This prevents
adjustments made by libata drivers to seep into the next driver which
gets attached (be it a libata one or not).
It's not clear whether SControl also needs to be restored on suspend.
The next system to have control (ACPI or kexec'd kernel) would
probably like to see the original SControl value but there's no
guarantee that a link is gonna keep working after SControl is adjusted
without a reset and adding a reset and modified recovery cycle soley
for this is an overkill. For now, do it only for detach.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Implement force params nohrst, nosrst and norst. This is to work
around reset related problems and ease debugging.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
- Add support for the RDC 1010 variant
- Rework the core library to have a read_id method. This allows the hacky
bits of it821x to go and prepares us for pata_hd
- Switch from WARN to BUG in ata_id_string as it will reboot if you get
it wrong so WARN won't be seen
- Allow the issue of command 0xFC on the 821x. This is needed to query
rebuild status.
- Tidy up printk formatting
- Do more ident rewriting on RAID volumes to handle firmware provided
ident data which is rather wonky
- Report the firmware revision and device layout in RAID mode
- Don't try and disable raid on the 8211 or RDC - they don't have the
relevant bits
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Add Enclosure Management support to libata and ahci.
Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
ATA_TMOUT_INTERNAL which was 30secs were used for all internal
commands which is way too long when something goes wrong. This patch
implements command type based stepped timeouts. Different command
types can use different timeouts and each command type can use
different timeout values after timeouts.
ie. the initial timeout is set to a value which should cover most of
the cases but not too long so that run away cases don't delay things
too much. After the first try times out, the second try can use
longer timeout and if that one times out too, it can go for full 30sec
timeout.
IDENTIFYs use 5s - 10s - 30s timeout and all other commands use 5s -
10s timeouts.
This patch significantly cuts down the needed time to handle failure
cases while still allowing libata to work with nut job devices through
retries.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
EH retries were delayed by 5 seconds to ensure that resets don't occur
back-to-back. However, this 5 second delay is superflous or excessive
in many cases. For example, after IDENTIFY times out, there's no
reason to wait five more seconds before retrying.
This patch adds ehc->last_reset timestamp and record the timestamp for
the last reset trial or success and uses it to space resets by
ATA_EH_RESET_COOL_DOWN which is 5 secs and removes unconditional 5 sec
sleeps.
As this change makes inter-try waits often shorter and they're
redundant in nature, this patch also removes the "retrying..."
messages.
While at it, convert explicit rounding up division to DIV_ROUND_UP().
This change speeds up EH in many cases w/o sacrificing robustness.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
libata has been using mix of jiffies and msecs for time druations.
This is getting confusing. As writing sub HZ values in jiffies is
PITA and msecs_to_jiffies() can't be used as initializer, unify unit
for all time durations to msecs. So, durations are in msecs and
deadlines are in jiffies. ata_deadline() is added to compute deadline
from a start time and duration in msecs.
While at it, drop now superflous _msec suffix from arguments and
rename @timeout to @deadline if it represents a fixed point in time
rather than duration.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
- Make ata_sff_altstatus private so nobody uses it by mistake
- Drop the 400nS delay from it
Add
ata_sff_irq_status - encapsulates the IRQ check logic
This function keeps the existing behaviour for altstatus using devices. I
actually suspect the logic was wrong before the changes but -rc isn't the
time to play with that
ata_sff_sync - ensure writes hit the device
Really we want an io* operation for 'is posted' eg ioisposted(ioaddr) so
that we can fix the nasty delay this causes on most systems.
- ata_sff_pause - 400nS delay
Ensure the command hit the device and delay 400nS
- ata_sff_dma_pause
Ensure the I/O hit the device and enforce an HDMA1:0 transition delay.
Requires altstatus register exists, BUG if not so we don't risk
corruption in MWDMA modes. (UDMA the checksum will save your backside in
theory)
The only other complication then is devices with their own handlers.
rb532 can use dma_pause but scc needs to access its own altstatus
register for internal errata workarounds so directly call the drivers own
altstatus function.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
I was hoping ATA_HORKAGE_NODMA | ATA_HORKAGE_SKIP_PM could keep it
happy but no even this doesn't work under certain configurations and
it's not like we can do anything useful with the cofig device anyway.
Replace ATA_HORKAGE_SKIP_PM with ATA_HORKAGE_DISABLE and use it for
the config device. This makes the device completely ignored by
libata.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This timeout was set low because previously PMP register access was
done via polling and register access timeouts could stack up. This is
no longer the case. One timeout will make all following accesses fail
immediately.
In rare cases both marvell and SIMG PMPs need almost a second. Bump
it to 3s.
While at it, rename it to SATA_PMP_RW_TIMEOUT. It's not specific to
SCR access.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Use the kernel-provided clamp_val() macro.
FIT was always applied to a member of struct ata_timing (unsigned short)
and two constants. clamp_val will not cast to short anymore.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This behavior differs across multiple controllers, so we cannot use
common logic for all controllers.
Revert back to the basic common behavior, and specific drivers will
be updated from here to take into account the unusual Status return
values.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Export ata_eh_analyze_ncq_error() for subsequent use by sata_mv,
as suggested by Tejun.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Some controllers (jmb and inic162x) use 0x77 and 0x7f to indicate that
the device isn't ready yet. It looks like they use 0xff if device
presence is detected but connection isn't established. 0x77 or 0x7f
after connection is established and use the value from signature FIS
after receiving it.
This patch implements ata_check_ready(), which takes TF status value
and determines whether the port is ready or not considering the above
and other conditions, and use it in @check_ready() functions. This is
safe as both 0x77 and 0x7f aren't valid ready status value even though
they have BSY bit cleared.
This fixes hot plug detection failures which can be triggered with
certain drives if they aren't already spun up when the data connector
is hot plugged.
Tested on sil, sil24, ahci (jmb/ich), piix and inic162x combined with
eight drives from all major vendors.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Put the big stuff at the end, to prepare for upcoming changes (and
also hopefully achieve nicer packing of remaining members).
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
It's big, but there doesn't seem to be a way to split it up smaller...
Signed-off-by: Tony Jones <tonyj@suse.de>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Sean Hefty <sean.hefty@intel.com>
Cc: Hal Rosenstock <hal.rosenstock@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Make PMP support optional by adding CONFIG_SATA_PMP and leaving out
libata-pmp.c if it isn't set. PMP helpers return constant values if
PMP support is not enabled and PMP declarations alias non-PMP
counterparts. This makes the compiler to leave out PMP related part
out and LLDs to use non-PMP counterparts automatically.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Implement helpers to test whether PMP is supported, attached and
determine pmp number to use when issuing SRST to a link. While at it,
move ata_is_host_link() so that it's together with the two new PMP
helpers.
This change simplifies LLDs and helps making PMP support optional.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Most of PMP support code is already in libata-pmp.c. All that are in
libata-core.c are sata_pmp_port_ops and EXPORTs. Move them to
libata-pmp.c. Also, collect PMP related prototypes and declarations
in header files and move them right above of SFF stuff.
This change is to make PMP support optional.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Now that SFF support is completely separated out from the core layer,
it can be made optional. Add CONFIG_ATA_SFF and let SFF drivers
depend on it. If CONFIG_ATA_SFF isn't set, all codes in libata-sff.c
and data structures for SFF support are disabled. This saves good
number of bytes for small systems.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Now that SFF assumptions are separated out from non-SFF reset
sequence, port_ops->sff_dev_select() is no longer necessary for
non-SFF controllers. Kill ata_noop_dev_select() and ->sff_dev_select
initialization from base and other non-SFF port_ops.
Signed-off-by: Tejun Heo <htejun@gmail.com>
ata_qc_complete_multiple() took @finish_qc and called it on every qc
before completing it. This was to give opportunity to update TF cache
before ata_qc_complete() tries to fill result_tf. Now that result TF
is a separate operation, this is no longer necessary.
Update sata_sil24, which was the only user of this mechanism, such
that it implements its own ops->qc_fill_rtf() and drop @finish_qc from
ata_qc_complete_multiple().
Signed-off-by: Tejun Heo <htejun@gmail.com>
On command completion, ata_qc_complete() directly called ops->tf_read
to fill qc->result_tf. This patch adds ops->qc_fill_rtf to replace
hardcoded ops->tf_read usage.
ata_sff_qc_fill_rtf() which uses ops->tf_read to fill result_tf is
implemented and set in ata_base_port_ops and other ops tables which
don't inherit from ata_base_port_ops, so this patch doesn't introduce
any behavior change.
ops->qc_fill_rtf() is similar to ops->sff_tf_read() but can only be
called when a command finishes. As some non-SFF controllers don't
have TF registers defined unless they're associated with in-flight
commands, this limited operation makes life easier for those drivers
and help lifting SFF assumptions from libata core layer.
Signed-off-by: Tejun Heo <htejun@gmail.com>
If PMP fan-out reset fails and SCR isn't accessible, PMP should be
reset. This used to be tested by sata_pmp_std_hardreset() and
communicated to EH by -ERESTART. However, this logic is generic and
doesn't really have much to do with specific hardreset implementation.
This patch moves SCR access failure detection logic to ata_eh_reset()
where it belongs. As this makes sata_pmp_std_hardreset() identical to
sata_std_hardreset(), the function is killed and replaced with the
standard method.
Signed-off-by: Tejun Heo <htejun@gmail.com>
SError used to be cleared in ->postreset. This has small hotplug race
condition. If a device is plugged in after reset is complete but
postreset hasn't run yet, its hotplug event gets lost when SError is
cleared. This patch makes sata_link_resume() clear SError. This
kills the race condition and makes a lot of sense as some PMP and host
PHYs don't work properly without SError cleared.
This change makes sata_pmp_std_{pre|post}_reset()'s unnecessary as
they become identical to ata_std counterparts. It also simplifies
sata_pmp_hardreset() and ahci_vt8251_hardreset().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Implement sata_std_hardreset(), which simply wraps around
sata_link_hardreset(). sata_std_hardreset() becomes new standard
hardreset method for sata_port_ops and sata_sff_hardreset() moves from
ata_base_port_ops to ata_sff_port_ops, which is where it really
belongs.
ata_is_builtin_hardreset() is added so that both
ata_std_error_handler() and ata_sff_error_handler() skip both builtin
hardresets if SCR isn't accessible.
piix_sidpr_hardreset() in ata_piix.c is identical to
sata_std_hardreset() in functionality and got replaced with the
standard function.
Signed-off-by: Tejun Heo <htejun@gmail.com>
sata_sff_hardreset() contains link readiness wait logic which isn't
SFF specific. Move that part into sata_link_hardreset(), which now
takes two more parameters - @online and @check_ready. Both are
optional. The former is out parameter for link onlineness after
reset. The latter is used to wait for link readiness after hardreset.
Users of sata_link_hardreset() is updated to use new funtionality and
ahci_hardreset() is updated to use sata_link_hardreset() instead of
sata_sff_hardreset(). This doesn't really cause any behavior change.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Factor out waiting logic (which is common to all ATA controllers) from
ata_sff_wait_ready() into ata_wait_ready(). ata_wait_ready() takes
@check_ready function pointer and uses it to poll for readiness. This
allows non-SFF controllers to use ata_wait_ready() to wait for link
readiness.
This patch also implements ata_wait_after_reset() - generic version of
ata_sff_wait_after_reset() - using ata_wait_ready().
ata_sff_wait_ready() is reimplemented using ata_wait_ready() and
ata_sff_check_ready(). Functionality remains the same.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Previously, post-softreset readiness is waited as follows.
1. ata_sff_wait_after_reset() waits for 150ms and then for
ATA_TMOUT_FF_WAIT if status is 0xff and other conditions meet.
2. ata_bus_softreset() finishes with -ENODEV if status is still 0xff.
If not, continue to #3.
3. ata_bus_post_reset() waits readiness of dev0 and/or dev1 depending
on devmask using ata_sff_wait_ready().
And for post-hardreset readiness,
1. ata_sff_wait_after_reset() waits for 150ms and then for
ATA_TMOUT_FF_WAIT if status is 0xff and other conditions meet.
2. sata_sff_hardreset waits for device readiness using
ata_sff_wait_ready().
This patch merges and unifies post-reset readiness waits into
ata_sff_wait_ready() and ata_sff_wait_after_reset().
ATA_TMOUT_FF_WAIT handling is merged into ata_sff_wait_ready(). If TF
status is 0xff, link status is unknown and the port is SATA, it will
continue polling till ATA_TMOUT_FF_WAIT.
ata_sff_wait_after_reset() is updated to perform the following steps.
1. waits for 150ms.
2. waits for dev0 readiness using ata_sff_wait_ready(). Note that
this is done regardless of devmask, as ata_sff_wait_ready() handles
0xff status correctly, this preserves the original behavior except
that it may wait longer after softreset if link is online but
status is 0xff. This behavior change is very unlikely to cause any
actual difference and is intended. It brings softreset behavior to
that of hardreset.
3. waits for dev1 readiness just the same way ata_bus_post_reset() did.
Now both soft and hard resets call ata_sff_wait_after_reset() after
reset to wait for readiness after resets. As
ata_sff_wait_after_reset() contains calls to ->sff_dev_select(),
explicit call near the end of sata_sff_hardreset() is removed.
This change makes reset implementation simpler and more consistent.
While at it, make the magical 150ms wait post-reset wait duration a
constant and ata_sff_wait_ready() and ata_sff_wait_after_reset() take
@link instead of @ap. This is to make them consistent with other
reset helpers and ease core changes.
pata_scc is updated accordingly.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Separate out generic ATA portion from ata_sff_postreset() into
ata_std_postreset() and implement ata_sff_postreset() using the std
version.
ata_base_port_ops now has ata_std_postreset() for its postreset and
ata_sff_port_ops overrides it to ata_sff_postreset().
This change affects pdc_adma, ahci, sata_fsl and sata_sil24. pdc_adma
now specifies postreset to ata_sff_postreset() explicitly. sata_fsl
and sata_sil24 now use ata_std_postreset() which makes no difference
to them. ahci now calls ata_std_postreset() from its own postreset
method, which causes no behavior difference.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Separate out generic ATA portion from ata_sff_prereset() into
ata_std_prereset() and implement ata_sff_prereset() using the std
version. Waiting for device readiness is the only SFF specific part.
ata_base_port_ops now has ata_std_prereset() for its prereset and
ata_sff_port_ops overrides it to ata_sff_prereset(). This change can
affect pdc_adma, ahci, sata_fsl and sata_sil24. pdc_adma implements
its own prereset using ata_sff_prereset() and the rest has hardreset
and thus are unaffected by this change.
This change reflects real world situation. There is no generic way to
wait for device readiness for non-SFF controllers and some of them
don't have any mechanism for that. Non-sff drivers which don't have
hardreset should wrap ata_std_prereset() and wait for device readiness
itself but there's no such driver now and isn't likely to be popular
in the future either.
Signed-off-by: Tejun Heo <htejun@gmail.com>
->sff_irq_clear() is called only from SFF interrupt handler, so there
is no reason to initialize it for non-SFF controllers. Also,
ata_sff_irq_clear() can handle both BMDMA and non-BMDMA SFF
controllers.
This patch kills ata_noop_irq_clear() and removes it from base
port_ops and sets ->sff_irq_clear to ata_sff_irq_clear() in sff
port_ops instead of bmdma port_ops.
Signed-off-by: Tejun Heo <htejun@gmail.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>
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>
Currently whether a command should be retried after failure is
determined inside ata_eh_finish(). Add ATA_QCFLAG_RETRY and move the
logic into ata_eh_autopsy(). This makes things clearer and helps
extending retry determination logic.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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>
ata_pci_default_filter() doesn't really have anything to do with PCI.
It's generally applicable to BMDMA controllers. Move it out of
CONFIG_PCI.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
* Move SFF related functions from libata-core.c to libata-sff.c.
ata_[bmdma_]sff_port_ops, ata_devchk(), ata_dev_try_classify(),
ata_std_dev_select(), ata_tf_to_host(), ata_busy_sleep(),
ata_wait_after_reset(), ata_wait_ready(), ata_bus_post_reset(),
ata_bus_softreset(), ata_bus_reset(), ata_std_softreset(),
sata_std_hardreset(), ata_fill_sg(), ata_fill_sg_dumb(),
ata_qc_prep(), ata_dump_qc_prep(), ata_data_xfer(),
ata_data_xfer_noirq(), ata_pio_sector(), ata_pio_sectors(),
atapi_send_cdb(), __atapi_pio_bytes(), atapi_pio_bytes(),
ata_hsm_ok_in_wq(), ata_hsm_qc_complete(), ata_hsm_move(),
ata_pio_task(), ata_qc_issue_prot(), ata_host_intr(),
ata_interrupt(), ata_std_ports()
* Make ata_pio_queue_task() global as it's now called from
libata-sff.c.
* Move SFF related stuff in include/linux/libata.h and
drivers/ata/libata.h into one place. While at it, move timing
constants into the global enum definition and fortify comments a
bit.
This patch strictly moves stuff around and as such doesn't cause any
functional difference.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Currently reset methods are not specified directly in the
ata_port_operations table. If a LLD wants to use custom reset
methods, it should construct and use a error_handler which uses those
reset methods. It's done this way for two reasons.
First, the ops table already contained too many methods and adding
four more of them would noticeably increase the amount of necessary
boilerplate code all over low level drivers.
Second, as ->error_handler uses those reset methods, it can get
confusing. ie. By overriding ->error_handler, those reset ops can be
made useless making layering a bit hazy.
Now that ops table uses inheritance, the first problem doesn't exist
anymore. The second isn't completely solved but is relieved by
providing default values - most drivers can just override what it has
implemented and don't have to concern itself about higher level
callbacks. In fact, there currently is no driver which actually
modifies error handling behavior. Drivers which override
->error_handler just wraps the standard error handler only to prepare
the controller for EH. I don't think making ops layering strict has
any noticeable benefit.
This patch makes ->prereset, ->softreset, ->hardreset, ->postreset and
their PMP counterparts propoer ops. Default ops are provided in the
base ops tables and drivers are converted to override individual reset
methods instead of creating custom error_handler.
* ata_std_error_handler() doesn't use sata_std_hardreset() if SCRs
aren't accessible. sata_promise doesn't need to use separate
error_handlers for PATA and SATA anymore.
* softreset is broken for sata_inic162x and sata_sx4. As libata now
always prefers hardreset, this doesn't really matter but the ops are
forced to NULL using ATA_OP_NULL for documentation purpose.
* pata_hpt374 needs to use different prereset for the first and second
PCI functions. This used to be done by branching from
hpt374_error_handler(). The proper way to do this is to use
separate ops and port_info tables for each function. Converted.
Signed-off-by: Tejun Heo <htejun@gmail.com>
libata core layer doesn't care about sht or ->irq_handler. Those are
only of interest to the LLD during initialization. This is confusing
and has caused several drivers to have duplicate unused initializers
for these fields.
Currently only sata_nv uses these fields. Make sata_nv use
->private_data, which is supposed to carry LLD-specific information,
instead and kill ->sht and ->irq_handler. nv_pi_priv structure is
defined and struct literals are used to initialize private_data.
Notational overhead is negligible.
Signed-off-by: Tejun Heo <htejun@gmail.com>
port_info->private_data is currently used for two purposes - to record
private data about the port_info or to specify host->private_data to
use when allocating ata_host.
This overloading is confusing and counter-intuitive in that
port_info->private_data becomes host->private_data instead of
port->private_data. In addition, port_info and host don't correspond
to each other 1-to-1. Currently, the first non-NULL
port_info->private_data is used.
This patch makes port_info->private_data just be what it is -
private_data for the port_info where LLD can jot down extra info.
libata no longer sets host->private_data to the first non-NULL
port_info->private_data, @host_priv argument is added to
ata_pci_init_one() instead. LLDs which use ata_pci_init_one() can use
this argument to pass in pointer to host private data. LLDs which
don't should use init-register model anyway and can initialize
host->private_data directly.
Adding @host_priv instead of using init-register model for LLDs which
use ata_pci_init_one() is suggested by Alan Cox.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
ata_pci_init_one() is the only function which uses ops->irq_handler
and pi->sht. Other initialization functions take the same information
as arguments. This causes confusion and duplicate unused entries in
structures.
Make ata_pci_init_one() take sht as an argument and use ata_interrupt
implicitly. All current users use ata_interrupt and if different irq
handler is necessary open coding ata_pci_init_one() using
ata_prepare_sff_host() and ata_activate_sff_host can be done under ten
lines including error handling and driver which requires custom
interrupt handler is likely to require custom initialization anyway.
As ata_pci_init_one() was the last user of ops->irq_handler, this
patch also kills the field.
Signed-off-by: Tejun Heo <htejun@gmail.com>
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>
->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>
