2 files changed, 73 insertions, 10 deletions

diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 9bf13988f1a2..ed6aa83d86dd 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -194,6 +194,8 @@ static int __devinit cciss_find_cfg_addrs(struct pci_dev *pdev,
 static int __devinit cciss_pci_find_memory_BAR(struct pci_dev *pdev,
         unsigned long *memory_bar);
 static inline u32 cciss_tag_discard_error_bits(ctlr_info_t *h, u32 tag);
+static __devinit int write_driver_ver_to_cfgtable(
+        CfgTable_struct __iomem *cfgtable);
 
 /* performant mode helper functions */
 static void  calc_bucket_map(int *bucket, int num_buckets, int nsgs,
@@ -4078,6 +4080,9 @@ static int __devinit cciss_find_cfgtables(ctlr_info_t *h)
                 cfg_base_addr_index) + cfg_offset, sizeof(h->cfgtable));
         if (!h->cfgtable)
                 return -ENOMEM;
+        rc = write_driver_ver_to_cfgtable(h->cfgtable);
+        if (rc)
+                return rc;
         /* Find performant mode table. */
         trans_offset = readl(&h->cfgtable->TransMethodOffset);
         h->transtable = remap_pci_mem(pci_resource_start(h->pdev,
@@ -4428,6 +4433,60 @@ static int cciss_controller_hard_reset(struct pci_dev *pdev,
         return 0;
 }
 
+static __devinit void init_driver_version(char *driver_version, int len)
+{
+        memset(driver_version, 0, len);
+        strncpy(driver_version, "cciss " DRIVER_NAME, len - 1);
+}
+
+static __devinit int write_driver_ver_to_cfgtable(
+        CfgTable_struct __iomem *cfgtable)
+{
+        char *driver_version;
+        int i, size = sizeof(cfgtable->driver_version);
+
+        driver_version = kmalloc(size, GFP_KERNEL);
+        if (!driver_version)
+                return -ENOMEM;
+
+        init_driver_version(driver_version, size);
+        for (i = 0; i < size; i++)
+                writeb(driver_version[i], &cfgtable->driver_version[i]);
+        kfree(driver_version);
+        return 0;
+}
+
+static __devinit void read_driver_ver_from_cfgtable(
+        CfgTable_struct __iomem *cfgtable, unsigned char *driver_ver)
+{
+        int i;
+
+        for (i = 0; i < sizeof(cfgtable->driver_version); i++)
+                driver_ver[i] = readb(&cfgtable->driver_version[i]);
+}
+
+static __devinit int controller_reset_failed(
+        CfgTable_struct __iomem *cfgtable)
+{
+
+        char *driver_ver, *old_driver_ver;
+        int rc, size = sizeof(cfgtable->driver_version);
+
+        old_driver_ver = kmalloc(2 * size, GFP_KERNEL);
+        if (!old_driver_ver)
+                return -ENOMEM;
+        driver_ver = old_driver_ver + size;
+
+        /* After a reset, the 32 bytes of "driver version" in the cfgtable
+         * should have been changed, otherwise we know the reset failed.
+         */
+        init_driver_version(old_driver_ver, size);
+        read_driver_ver_from_cfgtable(cfgtable, driver_ver);
+        rc = !memcmp(driver_ver, old_driver_ver, size);
+        kfree(old_driver_ver);
+        return rc;
+}
+
 /* This does a hard reset of the controller using PCI power management
  * states or using the doorbell register. */
 static __devinit int cciss_kdump_hard_reset_controller(struct pci_dev *pdev)
@@ -4437,7 +4496,7 @@ static __devinit int cciss_kdump_hard_reset_controller(struct pci_dev *pdev)
         u64 cfg_base_addr_index;
         void __iomem *vaddr;
         unsigned long paddr;
-        u32 misc_fw_support, active_transport;
+        u32 misc_fw_support;
         int rc;
         CfgTable_struct __iomem *cfgtable;
         bool use_doorbell;
@@ -4497,6 +4556,9 @@ static __devinit int cciss_kdump_hard_reset_controller(struct pci_dev *pdev)
                 rc = -ENOMEM;
                 goto unmap_vaddr;
         }
+        rc = write_driver_ver_to_cfgtable(cfgtable);
+        if (rc)
+                goto unmap_vaddr;
 
         /* If reset via doorbell register is supported, use that. */
         misc_fw_support = readl(&cfgtable->misc_fw_support);
@@ -4535,21 +4597,21 @@ static __devinit int cciss_kdump_hard_reset_controller(struct pci_dev *pdev)
                         "failed waiting for board to become ready\n");
                 goto unmap_cfgtable;
         }
-        dev_info(&pdev->dev, "board ready.\n");
 
-        /* Controller should be in simple mode at this point.  If it's not,
-         * It means we're on one of those controllers which doesn't support
-         * the doorbell reset method and on which the PCI power management reset
-         * method doesn't work (P800, for example.)
-         * In those cases, don't try to proceed, as it generally doesn't work.
-         */
-        active_transport = readl(&cfgtable->TransportActive);
-        if (active_transport & PERFORMANT_MODE) {
+        rc = controller_reset_failed(vaddr);
+        if (rc < 0)
+                goto unmap_cfgtable;
+        if (rc) {
                 dev_warn(&pdev->dev, "Unable to successfully reset controller,"
                         " Ignoring controller.\n");
                 rc = -ENODEV;
+                goto unmap_cfgtable;
+        } else {
+                dev_info(&pdev->dev, "board ready.\n");
         }
 
+        dev_info(&pdev->dev, "board ready.\n");
+
 unmap_cfgtable:
         iounmap(cfgtable);
 
diff --git a/drivers/block/cciss_cmd.h b/drivers/block/cciss_cmd.h
index cd441bef031f..a2e68d21efe3 100644
--- a/drivers/block/cciss_cmd.h
+++ b/drivers/block/cciss_cmd.h
@@ -235,6 +235,7 @@ typedef struct _CfgTable_struct {
   u8               reserved[0x78 - 0x58];
   u32              misc_fw_support; /* offset 0x78 */
 #define MISC_FW_DOORBELL_RESET (0x02)
+        u8         driver_version[32];
 } CfgTable_struct;
 
 struct TransTable_struct {