ACPICA 20050708 from Bob Moore <robert.moore@intel.com>

[linux-2.6] / drivers / acpi / tables / tbxfroot.c

diff --git a/drivers/acpi/tables/tbxfroot.c b/drivers/acpi/tables/tbxfroot.c
index dc3c3f6a9f621d5c93cf39bfa39ae6c4ee101399..abb4c934656049360163c09c54037392975f0ab6 100644 (file)
--- a/drivers/acpi/tables/tbxfroot.c
+++ b/drivers/acpi/tables/tbxfroot.c
@@ -63,6 +63,51 @@ acpi_tb_scan_memory_for_rsdp (
        u32                             length);
 
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_tb_validate_rsdp
+ *
+ * PARAMETERS:  Rsdp        - Pointer to unvalidated RSDP
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Validate the RSDP (ptr)
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_tb_validate_rsdp (
+       struct rsdp_descriptor          *rsdp)
+{
+       ACPI_FUNCTION_ENTRY ();
+
+
+       /*
+        *  The signature and checksum must both be correct
+        */
+       if (ACPI_STRNCMP ((char *) rsdp, RSDP_SIG, sizeof (RSDP_SIG)-1) != 0) {
+               /* Nope, BAD Signature */
+
+               return (AE_BAD_SIGNATURE);
+       }
+
+       /* Check the standard checksum */
+
+       if (acpi_tb_checksum (rsdp, ACPI_RSDP_CHECKSUM_LENGTH) != 0) {
+               return (AE_BAD_CHECKSUM);
+       }
+
+       /* Check extended checksum if table version >= 2 */
+
+       if ((rsdp->revision >= 2) &&
+               (acpi_tb_checksum (rsdp, ACPI_RSDP_XCHECKSUM_LENGTH) != 0)) {
+               return (AE_BAD_CHECKSUM);
+       }
+
+       return (AE_OK);
+}
+
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_tb_find_table
@@ -218,19 +263,11 @@ acpi_get_firmware_table (
                        acpi_gbl_RSDP = address.pointer.logical;
                }
 
-               /* The signature and checksum must both be correct */
-
-               if (ACPI_STRNCMP ((char *) acpi_gbl_RSDP, RSDP_SIG,
-                               sizeof (RSDP_SIG)-1) != 0) {
-                       /* Nope, BAD Signature */
-
-                       return_ACPI_STATUS (AE_BAD_SIGNATURE);
-               }
-
-               if (acpi_tb_checksum (acpi_gbl_RSDP, ACPI_RSDP_CHECKSUM_LENGTH) != 0) {
-                       /* Nope, BAD Checksum */
+               /* The RDSP signature and checksum must both be correct */
 
-                       return_ACPI_STATUS (AE_BAD_CHECKSUM);
+               status = acpi_tb_validate_rsdp (acpi_gbl_RSDP);
+               if (ACPI_FAILURE (status)) {
+                       return_ACPI_STATUS (status);
                }
        }
 
@@ -287,9 +324,11 @@ acpi_get_firmware_table (
         * requested table
         */
        for (i = 0, j = 0; i < table_count; i++) {
-               /* Get the next table pointer, handle RSDT vs. XSDT */
-
-               if (acpi_gbl_RSDP->revision < 2) {
+               /*
+                * Get the next table pointer, handle RSDT vs. XSDT
+                * RSDT pointers are 32 bits, XSDT pointers are 64 bits
+                */
+               if (acpi_gbl_root_table_type == ACPI_TABLE_TYPE_RSDT) {
                        address.pointer.value = (ACPI_CAST_PTR (
                                RSDT_DESCRIPTOR, rsdt_info->pointer))->table_offset_entry[i];
                }
@@ -331,8 +370,10 @@ acpi_get_firmware_table (
 
 
 cleanup:
-       acpi_os_unmap_memory (rsdt_info->pointer,
-               (acpi_size) rsdt_info->pointer->length);
+       if (rsdt_info->pointer) {
+               acpi_os_unmap_memory (rsdt_info->pointer,
+                       (acpi_size) rsdt_info->pointer->length);
+       }
        ACPI_MEM_FREE (rsdt_info);
 
        if (header) {
@@ -410,9 +451,9 @@ acpi_tb_scan_memory_for_rsdp (
        u8                              *start_address,
        u32                             length)
 {
+       acpi_status                     status;
        u8                              *mem_rover;
        u8                              *end_address;
-       u8                              checksum;
 
 
        ACPI_FUNCTION_TRACE ("tb_scan_memory_for_rsdp");
@@ -424,45 +465,25 @@ acpi_tb_scan_memory_for_rsdp (
 
        for (mem_rover = start_address; mem_rover < end_address;
                 mem_rover += ACPI_RSDP_SCAN_STEP) {
-               /* The signature and checksum must both be correct */
-
-               if (ACPI_STRNCMP ((char *) mem_rover,
-                               RSDP_SIG, sizeof (RSDP_SIG) - 1) != 0) {
-                       /* No signature match, keep looking */
-
-                       continue;
-               }
-
-               /* Signature matches, check the appropriate checksum */
-
-               if ((ACPI_CAST_PTR (struct rsdp_descriptor, mem_rover))->revision < 2) {
-                       /* ACPI version 1.0 */
+               /* The RSDP signature and checksum must both be correct */
 
-                       checksum = acpi_tb_checksum (mem_rover, ACPI_RSDP_CHECKSUM_LENGTH);
-               }
-               else {
-                       /* Post ACPI 1.0, use extended_checksum */
-
-                       checksum = acpi_tb_checksum (mem_rover, ACPI_RSDP_XCHECKSUM_LENGTH);
-               }
-
-               if (checksum == 0) {
-                       /* Checksum valid, we have found a valid RSDP */
+               status = acpi_tb_validate_rsdp (ACPI_CAST_PTR (struct rsdp_descriptor, mem_rover));
+               if (ACPI_SUCCESS (status)) {
+                       /* Sig and checksum valid, we have found a real RSDP */
 
                        ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
                                "RSDP located at physical address %p\n", mem_rover));
                        return_PTR (mem_rover);
                }
 
-               ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
-                       "Found an RSDP at physical address %p, but it has a bad checksum\n",
-                       mem_rover));
+               /* No sig match or bad checksum, keep searching */
        }
 
        /* Searched entire block, no RSDP was found */
 
        ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
-               "Searched entire block, no valid RSDP was found.\n"));
+               "Searched entire block from %p, valid RSDP was not found\n",
+               start_address));
        return_PTR (NULL);
 }
 
@@ -550,7 +571,7 @@ acpi_tb_find_rsdp (
                        acpi_os_unmap_memory (table_ptr, ACPI_EBDA_WINDOW_SIZE);
 
                        if (mem_rover) {
-                               /* Found it, return the physical address */
+                               /* Return the physical address */
 
                                physical_address += ACPI_PTR_DIFF (mem_rover, table_ptr);
 
@@ -579,7 +600,7 @@ acpi_tb_find_rsdp (
                acpi_os_unmap_memory (table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
 
                if (mem_rover) {
-                       /* Found it, return the physical address */
+                       /* Return the physical address */
 
                        physical_address =
                                ACPI_HI_RSDP_WINDOW_BASE + ACPI_PTR_DIFF (mem_rover, table_ptr);
@@ -610,7 +631,7 @@ acpi_tb_find_rsdp (
                                          ACPI_PHYSADDR_TO_PTR (physical_address),
                                          ACPI_EBDA_WINDOW_SIZE);
                        if (mem_rover) {
-                               /* Found it, return the physical address */
+                               /* Return the physical address */
 
                                table_info->physical_address = ACPI_TO_INTEGER (mem_rover);
                                return_ACPI_STATUS (AE_OK);
@@ -630,8 +651,9 @@ acpi_tb_find_rsdp (
                }
        }
 
-       /* RSDP signature was not found */
+       /* A valid RSDP was not found */
 
+       ACPI_REPORT_ERROR (("No valid RSDP was found\n"));
        return_ACPI_STATUS (AE_NOT_FOUND);
 }