From 239665a3bb0a2234980f918913add31bc536cfd1 Mon Sep 17 00:00:00 2001 From: Len Brown Date: Fri, 23 Nov 2007 20:08:02 -0500 Subject: 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 --- drivers/acpi/osl.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'drivers/acpi/osl.c') 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) -- cgit v1.2.2