On mainboards with analog VGA output the memory size is incorrectly detected due to an invalid register probe. This leads to a corrupted and unusable framebuffer on the analog VGA output.
Do not probe the DP501-related VGA scratch register if the DP501 device was not detected.
Tested-on: ASUS KGPE-D16 (AST2050) w/ 8MB VRAM.
Signed-off-by: Timothy Pearson tpearson@raptorengineering.com --- drivers/gpu/drm/ast/ast_main.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-)
diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c index 7bc3aa6..090b571 100644 --- a/drivers/gpu/drm/ast/ast_main.c +++ b/drivers/gpu/drm/ast/ast_main.c @@ -372,17 +372,19 @@ static u32 ast_get_vram_info(struct drm_device *dev) case 3: vram_size = AST_VIDMEM_SIZE_64M; break; }
- jreg = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x99, 0xff); - switch (jreg & 0x03) { - case 1: - vram_size -= 0x100000; - break; - case 2: - vram_size -= 0x200000; - break; - case 3: - vram_size -= 0x400000; - break; + if (ast->tx_chip_type == AST_TX_DP501) { + jreg = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0x99, 0xff); + switch (jreg & 0x03) { + case 1: + vram_size -= 0x100000; + break; + case 2: + vram_size -= 0x200000; + break; + case 3: + vram_size -= 0x400000; + break; + } }
return vram_size;