Commit 31fbc073 authored by Bob Moore's avatar Bob Moore Committed by Len Brown
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ACPICA: FADT: Favor 32-bit register addresses for compatibility



Use the 32-bit register addresses whenever they are non-zero. This
means that the 32-bit addresses are favored over the 64-bit
(GAS) addresses. The 64-bit addresses are only used if the 32-bit
addresses are zero. This change provides compatibility with all
versions of Windows. The worst case that this solves is when both
the 32-bit and 64-bit addresses are non-zero, but only the 32-bit
addresses are actually valid. This appears to happen in some
BIOSes because in this case, Windows uses the 32-bit addresses.
Signed-off-by: default avatarBob Moore <robert.moore@intel.com>
Signed-off-by: default avatarLin Ming <ming.m.lin@intel.com>
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent f28ad2c3
......@@ -320,29 +320,35 @@ void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)
* RETURN: None
*
* DESCRIPTION: Converts all versions of the FADT to a common internal format.
* Expand all 32-bit addresses to 64-bit.
* Expand 32-bit addresses to 64-bit as necessary.
*
* NOTE: acpi_gbl_FADT must be of size (struct acpi_table_fadt),
* and must contain a copy of the actual FADT.
*
* ACPICA will use the "X" fields of the FADT for all addresses.
* Notes on 64-bit register addresses:
*
* "X" fields are optional extensions to the original V1.0 fields. Even if
* they are present in the structure, they can be optionally not used by
* setting them to zero. Therefore, we must selectively expand V1.0 fields
* if the corresponding X field is zero.
* After this FADT conversion, later ACPICA code will only use the 64-bit "X"
* fields of the FADT for all ACPI register addresses.
*
* For ACPI 1.0 FADTs, all address fields are expanded to the corresponding
* "X" fields.
* The 64-bit "X" fields are optional extensions to the original 32-bit FADT
* V1.0 fields. Even if they are present in the FADT, they are optional and
* are unused if the BIOS sets them to zero. Therefore, we must copy/expand
* 32-bit V1.0 fields if the corresponding X field is zero.
*
* For ACPI 2.0 FADTs, any "X" fields that are NULL are filled in by
* expanding the corresponding ACPI 1.0 field.
* For ACPI 1.0 FADTs, all 32-bit address fields are expanded to the
* corresponding "X" fields in the internal FADT.
*
* For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded
* to the corresponding 64-bit X fields. For compatibility with other ACPI
* implementations, we ignore the 64-bit field if the 32-bit field is valid,
* regardless of whether the host OS is 32-bit or 64-bit.
*
******************************************************************************/
static void acpi_tb_convert_fadt(void)
{
struct acpi_generic_address *target64;
struct acpi_generic_address *address64;
u32 address32;
u32 i;
/* Update the local FADT table header length */
......@@ -391,29 +397,51 @@ static void acpi_tb_convert_fadt(void)
* Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"
* generic address structures as necessary. Later code will always use
* the 64-bit address structures.
*
* March 2009:
* We now always use the 32-bit address if it is valid (non-null). This
* is not in accordance with the ACPI specification which states that
* the 64-bit address supersedes the 32-bit version, but we do this for
* compatibility with other ACPI implementations. Most notably, in the
* case where both the 32 and 64 versions are non-null, we use the 32-bit
* version. This is the only address that is guaranteed to have been
* tested by the BIOS manufacturer.
*/
for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {
target64 =
ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,
fadt_info_table[i].address64);
address32 = *ACPI_ADD_PTR(u32,
&acpi_gbl_FADT,
fadt_info_table[i].address32);
/* Expand only if the 64-bit X target is null */
address64 = ACPI_ADD_PTR(struct acpi_generic_address,
&acpi_gbl_FADT,
fadt_info_table[i].address64);
if (!target64->address) {
/*
* If both 32- and 64-bit addresses are valid (non-zero),
* they must match.
*/
if (address64->address && address32 &&
(address64->address != (u64) address32)) {
ACPI_ERROR((AE_INFO,
"32/64X address mismatch in %s: %8.8X/%8.8X%8.8X, using 32",
fadt_info_table[i].name, address32,
ACPI_FORMAT_UINT64(address64->address)));
}
/* The space_id is always I/O for the 32-bit legacy address fields */
/* Always use 32-bit address if it is valid (non-null) */
acpi_tb_init_generic_address(target64,
if (address32) {
/*
* Copy the 32-bit address to the 64-bit GAS structure. The
* Space ID is always I/O for 32-bit legacy address fields
*/
acpi_tb_init_generic_address(address64,
ACPI_ADR_SPACE_SYSTEM_IO,
*ACPI_ADD_PTR(u8,
&acpi_gbl_FADT,
fadt_info_table
[i].length),
(u64) * ACPI_ADD_PTR(u32,
&acpi_gbl_FADT,
fadt_info_table
[i].
address32));
address32);
}
}
}
......@@ -530,18 +558,6 @@ static void acpi_tb_validate_fadt(void)
length));
}
}
/*
* If both 32- and 64-bit addresses are valid (non-zero),
* they must match
*/
if (address64->address && *address32 &&
(address64->address != (u64) * address32)) {
ACPI_ERROR((AE_INFO,
"32/64X address mismatch in %s: %8.8X/%8.8X%8.8X, using 64X",
name, *address32,
ACPI_FORMAT_UINT64(address64->address)));
}
}
}
......
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