cciss: add small delay when using PCI Power Management to reset for kump
Mike Miller [Thu, 20 Oct 2011 20:19:17 +0000 (22:19 +0200)]
commit ab5dbebe33e0c353e8545f09c34553ac3351dad6 upstream.

The P600 requires a small delay when changing states. Otherwise we may think
the board did not reset and we bail. This for kdump only and is particular
to the P600.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/block/cciss.c

index 8f4ef65..c2f9b3e 100644 (file)
@@ -4533,6 +4533,13 @@ static int cciss_controller_hard_reset(struct pci_dev *pdev,
                pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
                pmcsr |= PCI_D0;
                pci_write_config_word(pdev, pos + PCI_PM_CTRL, pmcsr);
+
+               /*
+                * The P600 requires a small delay when changing states.
+                * Otherwise we may think the board did not reset and we bail.
+                * This for kdump only and is particular to the P600.
+                */
+               msleep(500);
        }
        return 0;
 }