[PATCH] libata: preserve SATA SPD setting over hard resets

Don't overwrite SPD setting during hard reset.  This change has the
(intended) side effect of honoring the BIOS configuration.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 9 insertions, 3 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 061b0b6544cc..3acf56200d87 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -2132,9 +2132,11 @@ err_out:
 static int sata_phy_resume(struct ata_port *ap)
 {
         unsigned long timeout = jiffies + (HZ * 5);
-        u32 sstatus;
+        u32 scontrol, sstatus;
 
-        scr_write_flush(ap, SCR_CONTROL, 0x300);
+        scontrol = scr_read(ap, SCR_CONTROL);
+        scontrol = (scontrol & 0x0f0) | 0x300;
+        scr_write_flush(ap, SCR_CONTROL, scontrol);
 
         /* Wait for phy to become ready, if necessary. */
         do {
@@ -2247,10 +2249,14 @@ int ata_std_softreset(struct ata_port *ap, int verbose, unsigned int *classes)
  */
 int sata_std_hardreset(struct ata_port *ap, int verbose, unsigned int *class)
 {
+        u32 scontrol;
+
         DPRINTK("ENTER\n");
 
         /* Issue phy wake/reset */
-        scr_write_flush(ap, SCR_CONTROL, 0x301);
+        scontrol = scr_read(ap, SCR_CONTROL);
+        scontrol = (scontrol & 0x0f0) | 0x301;
+        scr_write_flush(ap, SCR_CONTROL, scontrol);
 
         /*
          * Couldn't find anything in SATA I/II specs, but AHCI-1.1