[SCSI] qla2xxx: Correct ISP24xx soft-reset handling.

A driver must wait 100us before attempting an MMIO operation
to the RISC after a soft-reset has been initiated.  A
similar delay was needed with earlier ISPs.

Note: a PCI config-space read is used to flush the MMIO
write to the ISP, since the ISP's state machines are unable
to respond to any MMIO read during the reset process.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/drivers/scsi/qla2xxx/qla_init.c b/drivers/scsi/qla2xxx/qla_init.c
index 8fb084b706e0..2d720121a0d3 100644
--- a/drivers/scsi/qla2xxx/qla_init.c
+++ b/drivers/scsi/qla2xxx/qla_init.c
@@ -567,6 +567,7 @@ qla24xx_reset_risc(scsi_qla_host_t *ha)
         unsigned long flags = 0;
         struct device_reg_24xx __iomem *reg = &ha->iobase->isp24;
         uint32_t cnt, d2;
+        uint16_t wd;
 
         spin_lock_irqsave(&ha->hardware_lock, flags);
 
@@ -581,10 +582,10 @@ qla24xx_reset_risc(scsi_qla_host_t *ha)
 
         WRT_REG_DWORD(&reg->ctrl_status,
             CSRX_ISP_SOFT_RESET|CSRX_DMA_SHUTDOWN|MWB_4096_BYTES);
-        RD_REG_DWORD(&reg->ctrl_status);
+        pci_read_config_word(ha->pdev, PCI_COMMAND, &wd);
 
+        udelay(100);
         /* Wait for firmware to complete NVRAM accesses. */
-        udelay(5);
         d2 = (uint32_t) RD_REG_WORD(&reg->mailbox0);
         for (cnt = 10000 ; cnt && d2; cnt--) {
                 udelay(5);
@@ -592,7 +593,7 @@ qla24xx_reset_risc(scsi_qla_host_t *ha)
                 barrier();
         }
 
-        udelay(20);
+        /* Wait for soft-reset to complete. */
         d2 = RD_REG_DWORD(&reg->ctrl_status);
         for (cnt = 6000000 ; cnt && (d2 & CSRX_ISP_SOFT_RESET); cnt--) {
                 udelay(5);