[PATCH] ahci: disable 64bit dma on sb600

SB600 claims it can do 64bit DMA but it can't.  Disable it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index fd27227771b48a8038ec867c62f9804fc34aa9af..efd87d34d584d5e3b0abdb41938c03e0db8f980f 100644 (file)
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -170,6 +170,7 @@ enum {
        AHCI_FLAG_IGN_IRQ_IF_ERR        = (1 << 25), /* ignore IRQ_IF_ERR */
        AHCI_FLAG_HONOR_PI              = (1 << 26), /* honor PORTS_IMPL */
        AHCI_FLAG_IGN_SERR_INTERNAL     = (1 << 27), /* ignore SERR_INTERNAL */
+       AHCI_FLAG_32BIT_ONLY            = (1 << 28), /* force 32bit */
 };
 
 struct ahci_cmd_hdr {
@@ -370,7 +371,8 @@ static const struct ata_port_info ahci_port_info[] = {
                .flags          = ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
                                  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA |
                                  ATA_FLAG_SKIP_D2H_BSY |
-                                 AHCI_FLAG_IGN_SERR_INTERNAL,
+                                 AHCI_FLAG_IGN_SERR_INTERNAL |
+                                 AHCI_FLAG_32BIT_ONLY,
                .pio_mask       = 0x1f, /* pio0-4 */
                .udma_mask      = 0x7f, /* udma0-6 ; FIXME */
                .port_ops       = &ahci_ops,
@@ -1579,6 +1581,12 @@ static int ahci_host_init(struct ata_probe_ent *probe_ent)
                probe_ent->n_ports = cap_n_ports;
 
        using_dac = hpriv->cap & HOST_CAP_64;
+       if (using_dac && (probe_ent->port_flags & AHCI_FLAG_32BIT_ONLY)) {
+               dev_printk(KERN_INFO, &pdev->dev,
+                          "controller can't do 64bit DMA, forcing 32bit\n");
+               using_dac = 0;
+       }
+
        if (using_dac &&
            !pci_set_dma_mask(pdev, DMA_64BIT_MASK)) {
                rc = pci_set_consistent_dma_mask(pdev, DMA_64BIT_MASK);