1. 27 5月, 2010 1 次提交
  2. 20 5月, 2010 9 次提交
    • K
      i2c-omap: add mpu wake up latency constraint in i2c · 20c9d2c4
      Kalle Jokiniemi 提交于
      While waiting for completion of the i2c transfer, the
      MPU could hit OFF mode and cause several msecs of
      delay that made i2c transfers fail more often. The
      extra delays and subsequent re-trys cause i2c clocks
      to be active more often. This has also an negative
      effect on power consumption.
      
      Created a mechanism for passing and using the
      constraint setting function in driver code. The used
      mpu wake up latency constraints are now set individually
      per bus, and they are calculated based on clock rate
      and fifo size.
      
      Thanks to Jarkko Nikula, Moiz Sonasath, Paul Walmsley,
      and Nishanth Menon for tuning out the details of
      this patch.
      
      Updates by Kevin as requested by Tony:
      
      - Remove omap_set_i2c_constraint_func() in favor of conditionally
        adding the flag in omap_i2c_add_bus() in order to keep all the OMAP
        conditional checking in a single location.
      - Update set_mpu_wkup_lat prototypes to match OMAP PM layer so
        OMAP PM function can be used directly in pdata.
      
      Cc: Moiz Sonasath <m-sonasath@ti.com>
      Cc: Jarkko Nikula <jhnikula@gmail.com>
      Cc: Paul Walmsley <paul@pwsan.com>
      Cc: Nishanth Menon <nm@ti.com>
      Signed-off-by: NKalle Jokiniemi <kalle.jokiniemi@digia.com>
      Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>
      Signed-off-by: NTony Lindgren <tony@atomide.com>
      Signed-off-by: NBen Dooks <ben-linux@fluff.org>
      20c9d2c4
    • T
      libata-sff: separate out BMDMA qc_issue · 360ff783
      Tejun Heo 提交于
      Separate out ata_bmdma_qc_issue() from ata_sff_qc_issue() such that
      ata_sff_qc_issue() only deals with non-BMDMA SFF protocols (PIO and
      nodata) while ata_bmdma_qc_issue() deals with the BMDMA protocols and
      uses ata_sff_qc_issue() for non-DMA commands.  All the users are
      updated accordingly.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      360ff783
    • T
      libata-sff: prd is BMDMA specific · f60d7011
      Tejun Heo 提交于
      struct ata_prd and ap->prd are BMDMA specific.  Add bmdma_ prefix to
      them and move them inside CONFIG_ATA_SFF.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      f60d7011
    • T
      libata-sff: ata_sff_[dumb_]qc_prep are BMDMA specific · f47451c4
      Tejun Heo 提交于
      Both qc_prep functions deal only with BMDMA PRD setup and PIO only SFF
      drivers don't need them.  Rename to ata_bmdma_[dumb_]qc_prep() and
      relocate.
      
      All usages are renamed except for pdc_adma and sata_qstor.  Those two
      drivers are not BMDMA drivers and don't need to call BMDMA qc_prep
      functions.  Calls to ata_sff_qc_prep() in the two drivers are removed.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      f47451c4
    • T
      libata-sff: separate out BMDMA EH · fe06e5f9
      Tejun Heo 提交于
      Some of error handling logic in ata_sff_error_handler() and all of
      ata_sff_post_internal_cmd() are for BMDMA.  Create
      ata_bmdma_error_handler() and ata_bmdma_post_internal_cmd() and move
      BMDMA part into those.
      
      While at it, change DMA protocol check to ata_is_dma(), fix
      post_internal_cmd to call ap->ops->bmdma_stop instead of directly
      calling ata_bmdma_stop() and open code hardreset selection so that
      ata_std_error_handler() doesn't have to know about sff hardreset.
      
      As these two functions are BMDMA specific, there's no reason to check
      for bmdma_addr before calling bmdma methods if the protocol of the
      failed command is DMA.  sata_mv and pata_mpc52xx now don't need to set
      .post_internal_cmd to ATA_OP_NULL and pata_icside and sata_qstor don't
      need to set it to their bmdma_stop routines.
      
      ata_sff_post_internal_cmd() becomes noop and is removed.
      
      This fixes p3 described in clean-up-BMDMA-initialization patch.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      fe06e5f9
    • T
      libata-sff: port_task is SFF specific · c429137a
      Tejun Heo 提交于
      port_task is tightly bound to the standard SFF PIO HSM implementation.
      Using it for any other purpose would be error-prone and there's no
      such user and if some drivers need such feature, it would be much
      better off using its own.  Move it inside CONFIG_ATA_SFF and rename it
      to sff_pio_task.
      
      The only function which is exposed to the core layer is
      ata_sff_flush_pio_task() which is renamed from ata_port_flush_task()
      and now also takes care of resetting hsm_task_state to HSM_ST_IDLE,
      which is possible as it's now specific to PIO HSM.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      c429137a
    • T
      libata-sff: ap->[last_]ctl are SFF specific · 5fe7454a
      Tejun Heo 提交于
      ap->[last_]ctl are specific to SFF controllers.  Put them inside
      CONFIG_ATA_SFF and move initialization into ata_sff_port_init().
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      5fe7454a
    • T
      libata-sff: rename ap->ops->drain_fifo() to sff_drain_fifo() · 8244cd05
      Tejun Heo 提交于
      ->drain_fifo() is SFF specific.  Rename and relocate it.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      8244cd05
    • T
      libata-sff: clean up BMDMA initialization · c7087652
      Tejun Heo 提交于
      When BMDMA initialization failed or BMDMA was not available for
      whatever reason, bmdma_addr was left at zero and used as an indication
      that BMDMA shouldn't be used.  This leads to the following problems.
      
      p1. For BMDMA drivers which don't use traditional BMDMA register,
          ata_bmdma_mode_filter() incorrectly inhibits DMA modes.  Those
          drivers either have to inherit from ata_sff_port_ops or clear
          ->mode_filter explicitly.
      
      p2. non-BMDMA drivers call into BMDMA PRD table allocation.  It
          doesn't actually allocate PRD table if bmdma_addr is not
          initialized but is still confusing.
      
      p3. For BMDMA drivers which don't use traditional BMDMA register, some
          methods might not be invoked as expected (e.g. bmdma_stop from
          ata_sff_post_internal_cmd()).
      
      p4. SFF drivers w/ custom DMA interface implement noop BMDMA ops
          worrying libata core might call into one of them.
      
      These problems are caused by the muddy line between SFF and BMDMA and
      the assumption that all BMDMA controllers initialize bmdma_addr.
      
      This patch fixes p1 and p2 by removing the bmdma_addr assumption and
      moving prd allocation to BMDMA port start.  Later patches will fix the
      remaining issues.
      
      This patch improves BMDMA initialization such that
      
      * When BMDMA register initialization fails, falls back to PIO instead
        of failing.  ata_pci_bmdma_init() never fails now.
      
      * When ata_pci_bmdma_init() falls back to PIO, it clears
        ap->mwdma_mask and udma_mask instead of depending on
        ata_bmdma_mode_filter().  This makes ata_bmdma_mode_filter()
        unnecessary thus resolving p1.
      
      * ata_port_start() which actually is BMDMA specific is moved to
        ata_bmdma_port_start().  ata_port_start() and ata_sff_port_start()
        are killed.
      
      * ata_sff_port_start32() is moved and renamed to
        ata_bmdma_port_start32().
      
      Drivers which no longer call into PRD table allocation are...
      
        pdc_adma, sata_inic162x, sata_qstor, sata_sx4, pata_cmd640 and all
        drivers which inherit from ata_sff_port_ops.
      
      pata_icside sets ->port_start to ATA_OP_NULL as it doesn't need PRD
      but is a BMDMA controller and doesn't have custom port_start like
      other such controllers.
      
      Note that with the previous patch which makes all and only BMDMA
      drivers inherit from ata_bmdma_port_ops, this change doesn't break
      drivers which need PRD table.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJeff Garzik <jgarzik@redhat.com>
      c7087652
  3. 19 5月, 2010 7 次提交
  4. 18 5月, 2010 10 次提交
  5. 17 5月, 2010 2 次提交
    • A
      atomic_t: Remove volatile from atomic_t definition · 81880d60
      Anton Blanchard 提交于
      When looking at a performance problem on PowerPC, I noticed some awful code
      generation:
      
      c00000000051fc98:       3b 60 00 01     li      r27,1
      ...
      c00000000051fca0:       3b 80 00 00     li      r28,0
      ...
      c00000000051fcdc:       93 61 00 70     stw     r27,112(r1)
      c00000000051fce0:       93 81 00 74     stw     r28,116(r1)
      c00000000051fce4:       81 21 00 70     lwz     r9,112(r1)
      c00000000051fce8:       80 01 00 74     lwz     r0,116(r1)
      c00000000051fcec:       7d 29 07 b4     extsw   r9,r9
      c00000000051fcf0:       7c 00 07 b4     extsw   r0,r0
      
      c00000000051fcf4:       7c 20 04 ac     lwsync
      c00000000051fcf8:       7d 60 f8 28     lwarx   r11,0,r31
      c00000000051fcfc:       7c 0b 48 00     cmpw    r11,r9
      c00000000051fd00:       40 c2 00 10     bne-    c00000000051fd10
      c00000000051fd04:       7c 00 f9 2d     stwcx.  r0,0,r31
      c00000000051fd08:       40 c2 ff f0     bne+    c00000000051fcf8
      c00000000051fd0c:       4c 00 01 2c     isync
      
      We create two constants, write them out to the stack, read them straight back
      in and sign extend them. What a mess.
      
      It turns out this bad code is a result of us defining atomic_t as a
      volatile int.
      
      We removed the volatile attribute from the powerpc atomic_t definition years
      ago, but commit ea435467 (atomic_t: unify all
      arch definitions) added it back in.
      
      To dig up an old quote from Linus:
      
      > The fact is, volatile on data structures is a bug. It's a wart in the C
      > language. It shouldn't be used.
      >
      > Volatile accesses in *code* can be ok, and if we have "atomic_read()"
      > expand to a "*(volatile int *)&(x)->value", then I'd be ok with that.
      >
      > But marking data structures volatile just makes the compiler screw up
      > totally, and makes code for initialization sequences etc much worse.
      
      And screw up it does :)
      
      With the volatile removed, we see much more reasonable code generation:
      
      c00000000051f5b8:       3b 60 00 01     li      r27,1
      ...
      c00000000051f5c0:       3b 80 00 00     li      r28,0
      ...
      
      c00000000051fc7c:       7c 20 04 ac     lwsync
      c00000000051fc80:       7c 00 f8 28     lwarx   r0,0,r31
      c00000000051fc84:       7c 00 d8 00     cmpw    r0,r27
      c00000000051fc88:       40 c2 00 10     bne-    c00000000051fc98
      c00000000051fc8c:       7f 80 f9 2d     stwcx.  r28,0,r31
      c00000000051fc90:       40 c2 ff f0     bne+    c00000000051fc80
      c00000000051fc94:       4c 00 01 2c     isync
      
      Six instructions less.
      Signed-off-by: NAnton Blanchard <anton@samba.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      81880d60
    • M
      [S390] add breaking event address for user space · 86f2552b
      Martin Schwidefsky 提交于
      Copy the last breaking event address from the lowcore to a new
      field in the thread_struct on each system entry. Add a new
      ptrace request PTRACE_GET_LAST_BREAK and a new utrace regset
      REGSET_LAST_BREAK to query the last breaking event.
      
      This is useful for debugging wild branches in user space code.
      Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      86f2552b
  6. 16 5月, 2010 1 次提交
  7. 15 5月, 2010 10 次提交