From: Liwei Song <liwei.s...@windriver.com>

This is a follow up to commit f712c71f7b2b ("ACPI, APEI: Fixup common
access width firmware bug") fix the following firmware bug:

[Firmware Bug]: APEI: Invalid bit width + offset in GAR [0xb2/16/0/1/1]

This is due to an 8-bit access width is specified for a 16-bit register,
Rearrange the condition and add 8-bit width check.

Signed-off-by: Liwei Song <liwei.s...@windriver.com>
---
 drivers/acpi/apei/apei-base.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/acpi/apei/apei-base.c b/drivers/acpi/apei/apei-base.c
index da370e1..eca3d7a 100644
--- a/drivers/acpi/apei/apei-base.c
+++ b/drivers/acpi/apei/apei-base.c
@@ -604,12 +604,12 @@ static int apei_check_gar(struct acpi_generic_address 
*reg, u64 *paddr,
        *access_bit_width = 1UL << (access_size_code + 2);
 
        /* Fixup common BIOS bug */
-       if (bit_width == 32 && bit_offset == 0 && (*paddr & 0x03) == 0 &&
-           *access_bit_width < 32)
-               *access_bit_width = 32;
-       else if (bit_width == 64 && bit_offset == 0 && (*paddr & 0x07) == 0 &&
-           *access_bit_width < 64)
-               *access_bit_width = 64;
+       if (*access_bit_width < bit_width && bit_offset == 0) {
+               if ((bit_width == 16 && (*paddr & 0x01) == 0) ||
+                   (bit_width == 32 && (*paddr & 0x03) == 0) ||
+                   (bit_width == 64 && (*paddr & 0x07) == 0))
+                       *access_bit_width = bit_width;
+       }
 
        if ((bit_width + bit_offset) > *access_bit_width) {
                pr_warning(FW_BUG APEI_PFX
-- 
2.7.4

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