isci: Fixup for OEM parameter EFI variable retrieval

Updating the EFI variable OEM parameter retrieval after examining the EFI
variable exported via sysfs.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

diff --git a/drivers/scsi/isci/probe_roms.c b/drivers/scsi/isci/probe_roms.c
index 64e9a80..0d968d3 100644 (file)
--- a/drivers/scsi/isci/probe_roms.c
+++ b/drivers/scsi/isci/probe_roms.c
@@ -61,6 +61,11 @@ struct isci_orom *isci_request_oprom(struct pci_dev *pdev)
 
        len = pci_biosrom_size(pdev);
        rom = devm_kzalloc(&pdev->dev, sizeof(*rom), GFP_KERNEL);
+       if (!rom) {
+               dev_warn(&pdev->dev,
+                        "Unable to allocate memory for orom\n");
+               return NULL;
+       }
 
        for (i = 0; i < len && rom; i += ISCI_OEM_SIG_SIZE) {
                memcpy_fromio(oem_sig, oprom + i, ISCI_OEM_SIG_SIZE);
@@ -181,7 +186,11 @@ struct isci_orom *isci_get_efi_var(struct pci_dev *pdev)
 {
        struct efi_variable *evar;
        efi_status_t status;
-       struct isci_orom *orom = NULL;
+       struct isci_orom *rom = NULL;
+       struct isci_oem_hdr *oem_hdr;
+       u8 *tmp, sum;
+       int j;
+       size_t copy_len;
 
        evar = devm_kzalloc(&pdev->dev,
                            sizeof(struct efi_variable),
@@ -192,6 +201,16 @@ struct isci_orom *isci_get_efi_var(struct pci_dev *pdev)
                return NULL;
        }
 
+       rom = devm_kzalloc(&pdev->dev, sizeof(*rom), GFP_KERNEL);
+       if (!rom) {
+               dev_warn(&pdev->dev,
+                        "Unable to allocate memory for orom\n");
+               return NULL;
+       }
+
+       for (j = 0; j < strlen(ISCI_EFI_VAR_NAME) + 1; j++)
+               evar->VariableName[j] = ISCI_EFI_VAR_NAME[j];
+
        evar->DataSize = 1024;
        evar->VendorGuid = ISCI_EFI_VENDOR_GUID;
        evar->Attributes = ISCI_EFI_ATTRIBUTES;
@@ -205,19 +224,48 @@ struct isci_orom *isci_get_efi_var(struct pci_dev *pdev)
        else
                status = EFI_NOT_FOUND;
 
-       if (status == EFI_SUCCESS)
-               orom = (struct isci_orom *)evar->Data;
-       else
+       if (status != EFI_SUCCESS) {
                dev_warn(&pdev->dev,
                         "Unable to obtain EFI variable for OEM parms\n");
+               return NULL;
+       }
+
+       oem_hdr = (struct isci_oem_hdr *)evar->Data;
 
-       if (orom && memcmp(orom->hdr.signature, ISCI_ROM_SIG,
-                          strlen(ISCI_ROM_SIG)) != 0)
+       if (memcmp(oem_hdr->sig, ISCI_OEM_SIG, ISCI_OEM_SIG_SIZE) != 0) {
                dev_warn(&pdev->dev,
-                        "Verifying OROM signature failed\n");
+                        "Invalid OEM header signature\n");
+               return NULL;
+       }
 
-       if (!orom)
-               devm_kfree(&pdev->dev, evar);
+       /* calculate checksum */
+       tmp = (u8 *)oem_hdr;
+       for (j = 0, sum = 0; j < sizeof(oem_hdr); j++, tmp++)
+               sum += *tmp;
 
-       return orom;
+       tmp = (u8 *)rom;
+       for (j = 0; j < sizeof(*rom); j++, tmp++)
+               sum += *tmp;
+
+       if (sum != 0) {
+               dev_warn(&pdev->dev,
+                        "OEM table checksum failed\n");
+               return NULL;
+       }
+
+       copy_len = min(evar->DataSize,
+                      min(oem_hdr->len - sizeof(*oem_hdr),
+                          sizeof(*rom)));
+
+       memcpy(rom, (char *)evar->Data + sizeof(*oem_hdr), copy_len);
+
+       if (memcmp(rom->hdr.signature,
+                  ISCI_ROM_SIG,
+                  ISCI_ROM_SIG_SIZE) != 0) {
+               dev_warn(&pdev->dev,
+                        "Invalid OEM table signature\n");
+               return NULL;
+       }
+
+       return rom;
 }

diff --git a/drivers/scsi/isci/probe_roms.h b/drivers/scsi/isci/probe_roms.h
index 0449239..c2162cf 100644 (file)
--- a/drivers/scsi/isci/probe_roms.h
+++ b/drivers/scsi/isci/probe_roms.h
@@ -100,7 +100,7 @@ struct isci_oem_hdr {
        EFI_GUID(0x193dfefa, 0xa445, 0x4302, 0x99, 0xd8, 0xef, 0x3a, 0xad, \
                        0x1a, 0x04, 0xc6)
 #define ISCI_EFI_ATTRIBUTES    0
-#define ISCI_EFI_VAR_NAME      "RST_SCU_OEM"
+#define ISCI_EFI_VAR_NAME      "RstScuO"
 
 /* Allowed PORT configuration modes APC Automatic PORT configuration mode is
  * defined by the OEM configuration parameters providing no PHY_MASK parameters