1. 04 Jun, 2008 1 commit
    • Alan Cox's avatar
      libata-sff: Fix oops reported in kerneloops.org for pnp devices with no ctl · a57c1bad
      Alan Cox authored
      - 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: default avatarAlan Cox <alan@redhat.com>
      Signed-off-by: default avatarJeff Garzik <jgarzik@redhat.com>
      a57c1bad
  2. 17 Apr, 2008 6 commits
    • Tejun Heo's avatar
      libata: rename SFF port ops · 5682ed33
      Tejun Heo authored
      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: default avatarTejun Heo <htejun@gmail.com>
      5682ed33
    • Tejun Heo's avatar
      libata: rename SFF functions · 9363c382
      Tejun Heo authored
      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: default avatarTejun Heo <htejun@gmail.com>
      9363c382
    • Tejun Heo's avatar
      libata: make reset related methods proper port operations · a1efdaba
      Tejun Heo authored
      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: default avatarTejun Heo <htejun@gmail.com>
      a1efdaba
    • Tejun Heo's avatar
      libata: implement and use ops inheritance · 029cfd6b
      Tejun Heo authored
      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: default avatarTejun Heo <htejun@gmail.com>
      029cfd6b
    • Tejun Heo's avatar
      libata: implement and use SHT initializers · 68d1d07b
      Tejun Heo authored
      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: default avatarTejun Heo <htejun@gmail.com>
      68d1d07b
    • Tejun Heo's avatar
      libata: implement and use ata_noop_irq_clear() · 358f9a77
      Tejun Heo authored
      ->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: default avatarTejun Heo <htejun@gmail.com>
      358f9a77
  3. 19 Feb, 2008 1 commit
    • James Bottomley's avatar
      libata: eliminate the home grown dma padding in favour of · dde20207
      James Bottomley authored
      that provided by the block layer
      
      ATA requires that all DMA transfers begin and end on word boundaries.
      Because of this, a large amount of machinery grew up in ide to adjust
      scatterlists on this basis.  However, as of 2.5, the block layer has a
      dma_alignment variable which ensures both the beginning and length of a
      DMA transfer are aligned on the dma_alignment boundary.  Although the
      block layer does adjust the beginning of the transfer to ensure this
      happens, it doesn't actually adjust the length, it merely makes sure
      that space is allocated for transfers beyond the declared length.  The
      upshot of this is that scatterlists may be padded to any size between
      the actual length and the length adjusted to the dma_alignment safely
      knowing that memory is allocated in this region.
      
      Right at the moment, SCSI takes the default dma_aligment which is on a
      512 byte boundary.  Note that this aligment only applies to transfers
      coming in from user space.  However, since all kernel allocations are
      automatically aligned on a minimum of 32 byte boundaries, it is safe to
      adjust them in this manner as well.
      
      tj: * Adjusting sg after padding is done in block layer.  Make libata
            set queue alignment correctly for ATAPI devices and drop broken
            sg mangling from ata_sg_setup().
          * Use request->raw_data_len for ATAPI transfer chunk size.
          * Killed qc->raw_nbytes.
          * Separated out killing qc->n_iter.
      Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
      Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      dde20207
  4. 23 Jan, 2008 1 commit
    • Tejun Heo's avatar
      libata: convert to chained sg · ff2aeb1e
      Tejun Heo authored
      libata used private sg iterator to handle padding sg.  Now that sg can
      be chained, padding can be handled using standard sg ops.  Convert to
      chained sg.
      
      * s/qc->__sg/qc->sg/
      
      * s/qc->pad_sgent/qc->extra_sg[]/.  Because chaining consumes one sg
        entry.  There need to be two extra sg entries.  The renaming is also
        for future addition of other extra sg entries.
      
      * Padding setup is moved into ata_sg_setup_extra() which is organized
        in a way that future addition of other extra sg entries is easy.
      
      * qc->orig_n_elem is unused and removed.
      
      * qc->n_elem now contains the number of sg entries that LLDs should
        map.  qc->mapped_n_elem is added to carry the original number of
        mapped sgs for unmapping.
      
      * The last sg of the original sg list is used to chain to extra sg
        list.  The original last sg is pointed to by qc->last_sg and the
        content is stored in qc->saved_last_sg.  It's restored during
        ata_sg_clean().
      
      * All sg walking code has been updated.  Unnecessary assertions and
        checks for conditions the core layer already guarantees are removed.
      Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
      Cc: Jens Axboe <jens.axboe@oracle.com>
      Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
      ff2aeb1e
  5. 25 Oct, 2007 1 commit
  6. 12 Oct, 2007 3 commits
    • Tejun Heo's avatar
      libata: implement and use ata_port_desc() to report port configuration · cbcdd875
      Tejun Heo authored
      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: default avatarTejun Heo <htejun@gmail.com>
      Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
      cbcdd875
    • Jeff Garzik's avatar
      [libata] Remove ->port_disable() hook · ac8869d5
      Jeff Garzik authored
      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: default avatarJeff Garzik <jeff@garzik.org>
      ac8869d5
    • Jeff Garzik's avatar
      [libata] Remove ->irq_ack() hook, and ata_dummy_irq_on() · 6d32d30f
      Jeff Garzik authored
      * ->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: default avatarJeff Garzik <jeff@garzik.org>
      6d32d30f
  7. 06 Aug, 2007 1 commit
  8. 09 Jul, 2007 1 commit
  9. 11 May, 2007 3 commits
  10. 03 May, 2007 1 commit