31 May, 2008

1 commit

  • The following commit (4c9bf4e799ce06a7378f1196587084802a414c03):
    libata: replace tf_read with qc_fill_rtf for non-SFF drivers

    Broke the sata_fsl.c driver in 2.6.26-rc. I know the following patch fixes
    the issue, it clearly also adds port multipler support. The current
    2.6.26-rc driver is broken.

    On boot with debug enabled we get something like (w/o this patch):

    spurious interrupt!!, CC = 0x1
    interrupt status 0x1
    xx_scr_read, reg_in = 1
    spurious interrupt!!, CC = 0x1
    interrupt status 0x1
    xx_scr_read, reg_in = 1
    spurious interrupt!!, CC = 0x1
    interrupt status 0x1
    xx_scr_read, reg_in = 1

    .. continues for ever.

    This change fixes this as a side effect of adding port multiplier support.

    Signed-off-by: Ashish Kalra
    Signed-off-by: Jeff Garzik

    Ashish Kalra
     

29 Apr, 2008

1 commit


18 Apr, 2008

12 commits

  • Currently, SATA softresets should do link onlineness check before
    actually performing SRST protocol but it doesn't really belong to
    softreset.

    This patch moves onlineness check in softreset to ata_eh_reset() and
    ata_eh_followup_srst_needed() to clean up code and help future sata_mv
    changes which need clear separation between SCR and TF accesses.

    sata_fsl is peculiar in that its softreset really isn't softreset but
    combination of hardreset and softreset. This patch adds dummy private
    ->prereset to keep the current behavior but the driver really should
    implement separate hard and soft resets and return -EAGAIN from
    hardreset if it should be follwed by softreset.

    Signed-off-by: Tejun Heo
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • ap->ioaddr is to carry addresses for TF and BMDMA registers of a SFF
    controller, don't abuse it in non-SFF controllers.

    Signed-off-by: Tejun Heo

    Tejun Heo
     
  • Now that all SFF stuff is separated out of core layer, core layer
    doesn't call ops->[alt_]check_status(). In fact, no one calls them
    for non-SFF drivers anymore. Kill them.

    Signed-off-by: Tejun Heo

    Tejun Heo
     
  • Now that all SFF stuff is separated out of core layer, core layer
    doesn't call ops->tf_read directly. It gets called only via
    ops->qc_fill_rtf() for non-SFF drivers. This patch directly
    implements private ops->qc_fill_rtf() for non-SFF controllers and kill
    ops->tf_read().

    This is much cleaner for non-SFF controllers as some of them have to
    cache SFF register values in private data structure and report the
    cached values via ops->tf_read(). Also, ops->tf_read() gets nasty for
    controllers which don't have clear notion of TF registers when
    operation is not in progress.

    As this change makes default ops->qc_fill_rtf unnecessary, move
    ata_sff_qc_fill_rtf() form ata_base_port_ops to ata_sff_port_ops where
    it belongs.

    Signed-off-by: Tejun Heo

    Tejun Heo
     
  • 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

    Tejun Heo
     
  • 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

    Tejun Heo
     
  • 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

    Tejun Heo
     
  • 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

    Tejun Heo
     
  • 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

    Tejun Heo
     
  • ->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

    Tejun Heo
     
  • 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

    Tejun Heo
     
  • 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

    Tejun Heo
     

09 Apr, 2008

1 commit


31 Mar, 2008

1 commit


24 Feb, 2008

1 commit

  • This patch fixes build and few warnings when ATA_VERBOSE_DEBUG
    is defined:

    CC drivers/ata/sata_fsl.o
    drivers/ata/sata_fsl.c: In function ‘sata_fsl_fill_sg’:
    drivers/ata/sata_fsl.c:338: warning: format ‘%x’ expects type ‘unsigned int’, but argument 3 has type ‘void *’
    drivers/ata/sata_fsl.c:338: warning: format ‘%x’ expects type ‘unsigned int’, but argument 4 has type ‘struct prde *’
    drivers/ata/sata_fsl.c: In function ‘sata_fsl_qc_issue’:
    drivers/ata/sata_fsl.c:459: error: ‘csr_base’ undeclared (first use in this function)
    drivers/ata/sata_fsl.c:459: error: (Each undeclared identifier is reported only once
    drivers/ata/sata_fsl.c:459: error: for each function it appears in.)
    drivers/ata/sata_fsl.c: In function ‘sata_fsl_freeze’:
    drivers/ata/sata_fsl.c:525: error: ‘csr_base’ undeclared (first use in this function)
    make[2]: *** [drivers/ata/sata_fsl.o] Error 1

    Signed-off-by: Anton Vorontsov
    Signed-off-by: Jeff Garzik

    Anton Vorontsov
     

19 Feb, 2008

1 commit

  • 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: James Bottomley
    Signed-off-by: Tejun Heo
    Signed-off-by: Jens Axboe

    James Bottomley
     

06 Feb, 2008

1 commit

  • qc->n_iter was used for libata's own sg walking before sg chaining
    replaced it. During conversion, the field and its usage in sata_fsl
    were left behind. Kill the filed and update sata_fsl.

    tj: This was part of James's libata-use-block-layer-padding patch.
    Separated out by me.

    Signed-off-by: James Bottomley
    Signed-off-by: Tejun Heo
    Cc: Li Yang
    Signed-off-by: Jeff Garzik

    James Bottomley
     

23 Jan, 2008

3 commits

  • drivers/ata/sata_fsl.c: In function 'sata_fsl_fill_sg':
    drivers/ata/sata_fsl.c:337: error: redeclaration of 'si' with no linkage
    drivers/ata/sata_fsl.c:326: error: previous declaration of 'si' was here

    Reported-by: Olof Johansson
    Cc: Jeff Garzik
    Signed-off-by: Andrew Morton
    Signed-off-by: Jeff Garzik

    akpm@linux-foundation.org
     
  • 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: Tejun Heo
    Cc: Jens Axboe
    Signed-off-by: Jeff Garzik

    Tejun Heo
     
  • 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
    Signed-off-by: Jeff Garzik

    Tejun Heo
     

03 Nov, 2007

12 commits


18 Oct, 2007

1 commit