[SCSI] hpsa: use new doorbell-bit-5 reset method

The bit-2-doorbell reset method seemed to cause (survivable) NMIs
on some systems and (unsurvivable) IOCK NMIs on some G7 servers.
Firmware guys implemented a new doorbell method to alleviate these
problems triggered by bit 5 of the doorbell register.  We want to
use it if it's available.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

2 files changed, 22 insertions, 5 deletions

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index ca92141b7736..c096cda3a6f4 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -3128,7 +3128,7 @@ static __devinit int hpsa_message(struct pci_dev *pdev, unsigned char opcode,
 #define hpsa_noop(p) hpsa_message(p, 3, 0)
 
 static int hpsa_controller_hard_reset(struct pci_dev *pdev,
-        void * __iomem vaddr, bool use_doorbell)
+        void * __iomem vaddr, u32 use_doorbell)
 {
         u16 pmcsr;
         int pos;
@@ -3139,7 +3139,7 @@ static int hpsa_controller_hard_reset(struct pci_dev *pdev,
                  * other way using the doorbell register.
                  */
                 dev_info(&pdev->dev, "using doorbell to reset controller\n");
-                writel(DOORBELL_CTLR_RESET, vaddr + SA5_DOORBELL);
+                writel(use_doorbell, vaddr + SA5_DOORBELL);
                 msleep(1000);
         } else { /* Try to do it the PCI power state way */
 
@@ -3243,7 +3243,7 @@ static __devinit int hpsa_kdump_hard_reset_controller(struct pci_dev *pdev)
         u32 misc_fw_support;
         int rc;
         struct CfgTable __iomem *cfgtable;
-        bool use_doorbell;
+        u32 use_doorbell;
         u32 board_id;
         u16 command_register;
 
@@ -3306,9 +3306,24 @@ static __devinit int hpsa_kdump_hard_reset_controller(struct pci_dev *pdev)
         if (rc)
                 goto unmap_vaddr;
 
-        /* If reset via doorbell register is supported, use that. */
+        /* If reset via doorbell register is supported, use that.
+         * There are two such methods.  Favor the newest method.
+         */
         misc_fw_support = readl(&cfgtable->misc_fw_support);
-        use_doorbell = misc_fw_support & MISC_FW_DOORBELL_RESET;
+        use_doorbell = misc_fw_support & MISC_FW_DOORBELL_RESET2;
+        if (use_doorbell) {
+                use_doorbell = DOORBELL_CTLR_RESET2;
+        } else {
+                use_doorbell = misc_fw_support & MISC_FW_DOORBELL_RESET;
+                if (use_doorbell) {
+                        dev_warn(&pdev->dev, "Controller claims that "
+                                "'Bit 2 doorbell reset' is "
+                                "supported, but not 'bit 5 doorbell reset'.  "
+                                "Firmware update is recommended.\n");
+                        rc = -ENODEV;
+                        goto unmap_cfgtable;
+                }
+        }
 
         rc = hpsa_controller_hard_reset(pdev, vaddr, use_doorbell);
         if (rc)
diff --git a/drivers/scsi/hpsa_cmd.h b/drivers/scsi/hpsa_cmd.h
index 8fd35a7abcd1..55d741b019db 100644
--- a/drivers/scsi/hpsa_cmd.h
+++ b/drivers/scsi/hpsa_cmd.h
@@ -101,6 +101,7 @@
 #define CFGTBL_ChangeReq        0x00000001l
 #define CFGTBL_AccCmds          0x00000001l
 #define DOORBELL_CTLR_RESET     0x00000004l
+#define DOORBELL_CTLR_RESET2    0x00000020l
 
 #define CFGTBL_Trans_Simple     0x00000002l
 #define CFGTBL_Trans_Performant 0x00000004l
@@ -337,6 +338,7 @@ struct CfgTable {
         u8              reserved[0x78 - 0x58];
         u32             misc_fw_support; /* offset 0x78 */
 #define                 MISC_FW_DOORBELL_RESET (0x02)
+#define                 MISC_FW_DOORBELL_RESET2 (0x010)
         u8              driver_version[32];
 };