From e615bf5b5519862ab66172f4dec7455d6543a578 Mon Sep 17 00:00:00 2001 From: Myron Stowe Date: Fri, 20 Jan 2012 19:13:24 -0700 Subject: 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 Signed-off-by: Len Brown --- drivers/acpi/apei/apei-base.c | 35 ++++------------------------------- 1 file changed, 4 insertions(+), 31 deletions(-) (limited to 'drivers/acpi/apei/apei-base.c') diff --git a/drivers/acpi/apei/apei-base.c b/drivers/acpi/apei/apei-base.c index e45350cb6ac8..e5d53b7ddc7e 100644 --- a/drivers/acpi/apei/apei-base.c +++ b/drivers/acpi/apei/apei-base.c @@ -596,33 +596,19 @@ int apei_read(u64 *val, struct acpi_generic_address *reg) { 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 apei_write(u64 val, struct acpi_generic_address *reg) { 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); -- cgit v1.2.1