drm/ast: Fix incorrect register check for DRAM width

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@raptorengineeringinc.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c
index 541a610..e0b4586 100644 (file)
--- a/drivers/gpu/drm/ast/ast_main.c
+++ b/drivers/gpu/drm/ast/ast_main.c
@@ -227,7 +227,7 @@ static int ast_get_dram_info(struct drm_device *dev)
        } 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;