src/patches/suse-2.6.27.31/patches.drivers/libata-whitelist-good-bridges

   1 From 9ce8e3073d9cfd6f859c22a25441db41b85cbf6e Mon Sep 17 00:00:00 2001
   2 From: Jens Axboe <jens.axboe@oracle.com>
   3 Date: Wed, 27 Aug 2008 15:23:18 +0200
   4 Subject: [PATCH] libata: add whitelist for devices with known good pata-sata bridges
   5
   6 libata currently imposes a UDMA5 max transfer rate and 200 sector max
   7 transfer size for SATA devices that sit behind a pata-sata bridge. Lots
   8 of devices have known good bridges that don't need this limit applied.
   9 The MTRON SSD disks are such devices. Transfer rates are increased by
  10 20-30% with the restriction removed.
  11
  12 So add a "blacklist" entry for the MTRON devices, with a flag indicating
  13 that the bridge is known good.
  14
  15 Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
  16 Signed-off-by: Tejun Heo <teheo@suse.de>
  17 ---
  18  drivers/ata/libata-core.c |    7 +++++++
  19  include/linux/libata.h    |    1 +
  20  2 files changed, 8 insertions(+)
  21
  22 --- a/drivers/ata/libata-core.c
  23 +++ b/drivers/ata/libata-core.c
  24 @@ -2163,6 +2163,10 @@ retry:
  25  static inline u8 ata_dev_knobble(struct ata_device *dev)
  26  {
  27         struct ata_port *ap = dev->link->ap;
  28 +
  29 +       if (ata_dev_blacklisted(dev) & ATA_HORKAGE_BRIDGE_OK)
  30 +               return 0;
  31 +
  32         return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
  33  }
  34
  35 @@ -4141,6 +4145,9 @@ static const struct ata_blacklist_entry
  36         { "TSSTcorp CDDVDW SH-S202N", "SB00",     ATA_HORKAGE_IVB, },
  37         { "TSSTcorp CDDVDW SH-S202N", "SB01",     ATA_HORKAGE_IVB, },
  38
  39 +       /* Devices that do not need bridging limits applied */
  40 +       { "MTRON MSP-SATA*",            NULL,   ATA_HORKAGE_BRIDGE_OK, },
  41 +
  42         /* End Marker */
  43         { }
  44  };
  45 --- a/include/linux/libata.h
  46 +++ b/include/linux/libata.h
  47 @@ -371,6 +371,7 @@ enum {
  48         ATA_HORKAGE_IPM         = (1 << 7),     /* Link PM problems */
  49         ATA_HORKAGE_IVB         = (1 << 8),     /* cbl det validity bit bugs */
  50         ATA_HORKAGE_STUCK_ERR   = (1 << 9),     /* stuck ERR on next PACKET */
  51 +       ATA_HORKAGE_BRIDGE_OK   = (1 << 10),    /* no bridge limits */
  52         ATA_HORKAGE_FIRMWARE_WARN = (1 << 12),  /* firwmare update warning */
  53
  54          /* DMA mask for user DMA control: User visible values; DO NOT