I haven't seen anyone work on the recent SB600 errata, where the
hardware does not like 256-length PRD entries.
Is this correct, AMD folks?
It hurts performance on SB600, but it is more important to get a
correct patch eliminating the data corruption/lockups, and then later
on tune for performance.
We simply limit each command to a maximum of 255 sectors, on SB600.
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
---
drivers/ata/ahci.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 1db93b6..8a49835 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -186,6 +186,7 @@ enum {
AHCI_HFLAG_NO_MSI = (1 << 5), /* no PCI MSI */
AHCI_HFLAG_NO_PMP = (1 << 6), /* no PMP */
AHCI_HFLAG_NO_HOTPLUG = (1 << 7), /* ignore PxSERR.DIAG.N */
+ AHCI_HFLAG_SECT255 = (1 << 8), /* max 255 sectors */
/* ap->flags bits */
@@ -255,6 +256,7 @@ static void ahci_vt8251_error_handler(struct ata_port *ap);
static void ahci_p5wdh_error_handler(struct ata_port *ap);
static void ahci_post_internal_cmd(struct ata_queued_cmd *qc);
static int ahci_port_resume(struct ata_port *ap);
+static void ahci_dev_config(struct ata_device *dev);
static unsigned int ahci_fill_sg(struct ata_queued_cmd *qc, void *cmd_tbl);
static void ahci_fill_cmd_slot(struct ahci_port_priv *pp, unsigned int tag,
u32 opts);
@@ -294,6 +296,8 @@ static const struct ata_port_operations ahci_ops = {
.check_altstatus = ahci_check_status,
.dev_select = ata_noop_dev_select,
+ .dev_config = ahci_dev_config,
+
.tf_read = ahci_tf_read,
.qc_defer = sata_pmp_qc_defer_cmd_switch,
@@ -425,7 +429,7 @@ static const struct ata_port_info ahci_port_info[] = {
/* board_ahci_sb600 */
{
AHCI_HFLAGS (AHCI_HFLAG_IGN_SERR_INTERNAL |
- AHCI_HFLAG_32BIT_ONLY | AHCI_HFLAG_NO_PMP),
+ AHCI_HFLAG_SECT255 | AHCI_HFLAG_NO_PMP),
.flags = AHCI_FLAG_COMMON,
.link_flags = AHCI_LFLAG_COMMON,
.pio_mask = 0x1f, /* pio0-4 */
@@ -1176,6 +1180,14 @@ static void ahci_init_controller(struct ata_host *host)
VPRINTK("HOST_CTL 0x%x\n", tmp);
}
+static void ahci_dev_config(struct ata_device *dev)
+{
+ struct ahci_host_priv *hpriv = dev->link->ap->host->private_data;
+
+ if (hpriv->flags & AHCI_HFLAG_SECT255)
+ dev->max_sectors = 255;
+}
+
static unsigned int ahci_dev_classify(struct ata_port *ap)
{
void __iomem *port_mmio = ahci_port_base(ap);
--
