From 69ec87efa815d69140423014bb5f91e034faac22 Mon Sep 17 00:00:00 2001 From: Lin Ming Date: Thu, 1 Apr 2010 11:14:12 +0800 Subject: ACPICA: Add subsystem option to force copy of DSDT to local memory Optionally copy the entire DSDT to local memory (instead of simply mapping it.) There are some BIOSs that corrupt or replace the original DSDT, creating the need for this option. Default is FALSE, do not copy the DSDT. https://bugzilla.kernel.org/show_bug.cgi?id=14679 Signed-off-by: Lin Ming Signed-off-by: Bob Moore Signed-off-by: Len Brown --- drivers/acpi/acpica/tbutils.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) (limited to 'drivers/acpi/acpica/tbutils.c') diff --git a/drivers/acpi/acpica/tbutils.c b/drivers/acpi/acpica/tbutils.c index 07bc7437f82b..1efb0940e8b2 100644 --- a/drivers/acpi/acpica/tbutils.c +++ b/drivers/acpi/acpica/tbutils.c @@ -385,6 +385,41 @@ void acpi_tb_check_dsdt_header(void) } } +/******************************************************************************* + * + * FUNCTION: acpi_tb_copy_dsdt + * + * PARAMETERS: table_desc - Installed table to copy + * + * RETURN: None + * + * DESCRIPTION: Implements a subsystem option to copy the DSDT to local memory. + * Some very bad BIOSs are known to either corrupt the DSDT or + * install a new, bad DSDT. This copy works around the problem. + * + ******************************************************************************/ + +void acpi_tb_copy_dsdt(struct acpi_table_desc *table_desc) +{ + struct acpi_table_header *new_table; + + new_table = ACPI_ALLOCATE(table_desc->length); + if (!new_table) { + ACPI_ERROR((AE_INFO, "Could not copy DSDT of length 0x%X", + table_desc->length)); + return; + } + + ACPI_MEMCPY(new_table, table_desc->pointer, table_desc->length); + acpi_tb_delete_table(table_desc); + table_desc->pointer = new_table; + table_desc->flags = ACPI_TABLE_ORIGIN_ALLOCATED; + + ACPI_INFO((AE_INFO, + "Forced DSDT copy: length 0x%05X copied locally, original unmapped", + new_table->length)); +} + /******************************************************************************* * * FUNCTION: acpi_tb_install_table -- cgit v1.2.2