ACPI, APEI: Add 64-bit read/write support for APEI on i386
Base ACPI (CA) currently does not support atomic 64-bit reads and writes
(acpi_read() and acpi_write() split 64-bit loads/stores into two
32-bit transfers) yet APEI expects 64-bit transfer capability, even
when running on 32-bit systems.
This patch implements 64-bit read and write routines for APEI usage.
This patch re-factors similar functionality introduced in commit
04c25997c97, bringing it into the ACPI subsystem in preparation for
removing ./drivers/acpi/atomicio.[ch]. In the implementation I have
replicated acpi_os_read_memory() and acpi_os_write_memory(), creating
64-bit versions for APEI to utilize, as opposed to something more
elegant. My thinking is that we should attempt to see if we can get
ACPI's CA/OSL changed so that the existing acpi_read() and acpi_write()
interfaces are natively 64-bit capable and then subsequently remove the
replication.
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/apei/apei-base.c b/drivers/acpi/apei/apei-base.c
index e45350c..e5d53b7 100644
--- a/drivers/acpi/apei/apei-base.c
+++ b/drivers/acpi/apei/apei-base.c
@@ -596,33 +596,19 @@
{
int rc;
u64 address;
- u32 tmp, width = reg->bit_width;
acpi_status status;
rc = apei_check_gar(reg, &address);
if (rc)
return rc;
- if (width == 64)
- width = 32; /* Break into two 32-bit transfers */
-
*val = 0;
switch(reg->space_id) {
case ACPI_ADR_SPACE_SYSTEM_MEMORY:
- status = acpi_os_read_memory((acpi_physical_address)
- address, &tmp, width);
+ status = acpi_os_read_memory64((acpi_physical_address)
+ address, val, reg->bit_width);
if (ACPI_FAILURE(status))
return -EIO;
- *val = tmp;
-
- if (reg->bit_width == 64) {
- /* Read the top 32 bits */
- status = acpi_os_read_memory((acpi_physical_address)
- (address + 4), &tmp, 32);
- if (ACPI_FAILURE(status))
- return -EIO;
- *val |= ((u64)tmp << 32);
- }
break;
case ACPI_ADR_SPACE_SYSTEM_IO:
status = acpi_os_read_port(address, (u32 *)val, reg->bit_width);
@@ -642,31 +628,18 @@
{
int rc;
u64 address;
- u32 width = reg->bit_width;
acpi_status status;
rc = apei_check_gar(reg, &address);
if (rc)
return rc;
- if (width == 64)
- width = 32; /* Break into two 32-bit transfers */
-
switch (reg->space_id) {
case ACPI_ADR_SPACE_SYSTEM_MEMORY:
- status = acpi_os_write_memory((acpi_physical_address)
- address, ACPI_LODWORD(val),
- width);
+ status = acpi_os_write_memory64((acpi_physical_address)
+ address, val, reg->bit_width);
if (ACPI_FAILURE(status))
return -EIO;
-
- if (reg->bit_width == 64) {
- status = acpi_os_write_memory((acpi_physical_address)
- (address + 4),
- ACPI_HIDWORD(val), 32);
- if (ACPI_FAILURE(status))
- return -EIO;
- }
break;
case ACPI_ADR_SPACE_SYSTEM_IO:
status = acpi_os_write_port(address, val, reg->bit_width);