[PATCH 3.10 05/24] drm/ast: Fix incorrect register check for DRAM width

From: Greg Kroah-Hartman
Date: Mon Mar 07 2016 - 18:46:05 EST


3.10-stable review patch. If anyone has any objections, please let me know.

------------------

From: Timothy Pearson <tpearson@xxxxxxxxxxxxxxxxxxxxxxxx>

commit 2d02b8bdba322b527c5f5168ce1ca10c2d982a78 upstream.

During DRAM initialization on certain ASpeed devices, an incorrect
bit (bit 10) was checked in the "SDRAM Bus Width Status" register
to determine DRAM width.

Query bit 6 instead in accordance with the Aspeed AST2050 datasheet v1.05.

Signed-off-by: Timothy Pearson <tpearson@xxxxxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/gpu/drm/ast/ast_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/gpu/drm/ast/ast_main.c
+++ b/drivers/gpu/drm/ast/ast_main.c
@@ -124,7 +124,7 @@ static int ast_get_dram_info(struct drm_
} while (ast_read32(ast, 0x10000) != 0x01);
data = ast_read32(ast, 0x10004);

- if (data & 0x400)
+ if (data & 0x40)
ast->dram_bus_width = 16;
else
ast->dram_bus_width = 32;