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/osl.c | |
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/osl.c')
-rw-r--r-- | drivers/acpi/osl.c | 8 |
1 files changed, 6 insertions, 2 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) |