diff options
Diffstat (limited to 'drivers/acpi/tables/tbxfroot.c')
| -rw-r--r-- | drivers/acpi/tables/tbxfroot.c | 120 |
1 files changed, 71 insertions, 49 deletions
diff --git a/drivers/acpi/tables/tbxfroot.c b/drivers/acpi/tables/tbxfroot.c index dc3c3f6a9f6..87dccdda9ae 100644 --- a/drivers/acpi/tables/tbxfroot.c +++ b/drivers/acpi/tables/tbxfroot.c @@ -65,6 +65,51 @@ acpi_tb_scan_memory_for_rsdp ( /******************************************************************************* * + * 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_generate_checksum (rsdp, ACPI_RSDP_CHECKSUM_LENGTH) != 0) { + return (AE_BAD_CHECKSUM); + } + + /* Check extended checksum if table version >= 2 */ + + if ((rsdp->revision >= 2) && + (acpi_tb_generate_checksum (rsdp, ACPI_RSDP_XCHECKSUM_LENGTH) != 0)) { + return (AE_BAD_CHECKSUM); + } + + return (AE_OK); +} + + +/******************************************************************************* + * * FUNCTION: acpi_tb_find_table * * PARAMETERS: Signature - String with ACPI table signature @@ -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); } |