From: "Y.C. Chen" <yc_chen@xxxxxxxxxxxxxx> [ Upstream commit 05b439711f6ff8700e8660f97a1179650778b9cb ] There is another thread still access standard VGA I/O while loading drm driver. Disable standard VGA I/O decode to avoid this issue. Signed-off-by: Y.C. Chen <yc_chen@xxxxxxxxxxxxxx> Reviewed-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/1523410059-18415-1-git-send-email-yc_chen@xxxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/ast/ast_main.c | 5 ++++- drivers/gpu/drm/ast/ast_mode.c | 2 +- drivers/gpu/drm/ast/ast_post.c | 2 +- 3 files changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c index 373700c05a00f..224fa1ef87ff9 100644 --- a/drivers/gpu/drm/ast/ast_main.c +++ b/drivers/gpu/drm/ast/ast_main.c @@ -131,8 +131,8 @@ static int ast_detect_chip(struct drm_device *dev, bool *need_post) /* Enable extended register access */ - ast_enable_mmio(dev); ast_open_key(ast); + ast_enable_mmio(dev); /* Find out whether P2A works or whether to use device-tree */ ast_detect_config_mode(dev, &scu_rev); @@ -576,6 +576,9 @@ void ast_driver_unload(struct drm_device *dev) { struct ast_private *ast = dev->dev_private; + /* enable standard VGA decode */ + ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xa1, 0x04); + ast_release_firmware(dev); kfree(ast->dp501_fw_addr); ast_mode_fini(dev); diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c index 8bb355d5d43d8..9d92d2d2fcfc7 100644 --- a/drivers/gpu/drm/ast/ast_mode.c +++ b/drivers/gpu/drm/ast/ast_mode.c @@ -600,7 +600,7 @@ static int ast_crtc_mode_set(struct drm_crtc *crtc, return -EINVAL; ast_open_key(ast); - ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xa1, 0xff, 0x04); + ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xa1, 0x06); ast_set_std_reg(crtc, adjusted_mode, &vbios_mode); ast_set_crtc_reg(crtc, adjusted_mode, &vbios_mode); diff --git a/drivers/gpu/drm/ast/ast_post.c b/drivers/gpu/drm/ast/ast_post.c index f7d421359d564..c1d1ac51d1c20 100644 --- a/drivers/gpu/drm/ast/ast_post.c +++ b/drivers/gpu/drm/ast/ast_post.c @@ -46,7 +46,7 @@ void ast_enable_mmio(struct drm_device *dev) { struct ast_private *ast = dev->dev_private; - ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xa1, 0xff, 0x04); + ast_set_index_reg(ast, AST_IO_CRTC_PORT, 0xa1, 0x06); } -- 2.20.1