diff options
| author | Len Brown <len.brown@intel.com> | 2007-11-23 20:08:02 -0500 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2007-12-14 02:36:24 -0500 |
| commit | 239665a3bb0a2234980f918913add31bc536cfd1 (patch) | |
| tree | 260262706ce5223bf3d1cec0e8083ea42260f2fb /drivers/acpi | |
| parent | 2ffbb8377c7a0713baf6644e285adc27a5654582 (diff) | |
| download | lwn-239665a3bb0a2234980f918913add31bc536cfd1.tar.gz lwn-239665a3bb0a2234980f918913add31bc536cfd1.zip | |
ACPI: tables: complete searching upon RSDP w/ bad checksum.
ACPI tables follow a tree structure in memory.
The root of the tree is the RSDP (Root System Description Pointer).
To find the RSDP, the OS searches for the signature "RSD PTR "
in well known physical memory locations. Then the OS computes
a table checksum to verify that the signature is really part
of a valid table header.
Some systems have a proper signature but an invalid checksum;
followed elsewhere by a proper signature with valid checksum.
http://bugzilla.kernel.org/show_bug.cgi?id=9444
The Linux RSDP scanning code bailed out on those systems
and as a result they booted with ACPI disabled.
Fix this by deleting the Linux RSDP scanning code and
plugging in the ACPICA RSDP scanning code.
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/osl.c | 8 | ||||
| -rw-r--r-- | drivers/acpi/tables/Makefile | 2 | ||||
| -rw-r--r-- | drivers/acpi/tables/tbxfroot.c | 4 |
3 files changed, 8 insertions, 6 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index aabc6ca4a81c..101691ef66cb 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -207,8 +207,12 @@ acpi_physical_address __init acpi_os_get_root_pointer(void) "System description tables not found\n"); return 0; } - } else - return acpi_find_rsdp(); + } else { + acpi_physical_address pa = 0; + + acpi_find_root_pointer(&pa); + return pa; + } } void __iomem *acpi_os_map_memory(acpi_physical_address phys, acpi_size size) diff --git a/drivers/acpi/tables/Makefile b/drivers/acpi/tables/Makefile index 0a7d7afac255..7385efa61622 100644 --- a/drivers/acpi/tables/Makefile +++ b/drivers/acpi/tables/Makefile @@ -2,6 +2,6 @@ # Makefile for all Linux ACPI interpreter subdirectories # -obj-y := tbxface.o tbinstal.o tbutils.o tbfind.o tbfadt.o +obj-y := tbxface.o tbinstal.o tbutils.o tbfind.o tbfadt.o tbxfroot.o EXTRA_CFLAGS += $(ACPI_CFLAGS) diff --git a/drivers/acpi/tables/tbxfroot.c b/drivers/acpi/tables/tbxfroot.c index cf8fa514189f..9ecb4b6c1e7d 100644 --- a/drivers/acpi/tables/tbxfroot.c +++ b/drivers/acpi/tables/tbxfroot.c @@ -100,7 +100,7 @@ static acpi_status acpi_tb_validate_rsdp(struct acpi_table_rsdp *rsdp) /******************************************************************************* * - * FUNCTION: acpi_tb_find_rsdp + * FUNCTION: acpi_find_root_pointer * * PARAMETERS: table_address - Where the table pointer is returned * @@ -219,8 +219,6 @@ acpi_status acpi_find_root_pointer(acpi_native_uint * table_address) return_ACPI_STATUS(AE_NOT_FOUND); } -ACPI_EXPORT_SYMBOL(acpi_find_root_pointer) - /******************************************************************************* * * FUNCTION: acpi_tb_scan_memory_for_rsdp |