diff options
Diffstat (limited to 'common/recipes-kernel/linux/linux-yocto-4.19.8/1500-drm-amd-display-Pass-app_tf-by-value-rather-than-by-.patch')
| -rw-r--r-- | common/recipes-kernel/linux/linux-yocto-4.19.8/1500-drm-amd-display-Pass-app_tf-by-value-rather-than-by-.patch | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/common/recipes-kernel/linux/linux-yocto-4.19.8/1500-drm-amd-display-Pass-app_tf-by-value-rather-than-by-.patch b/common/recipes-kernel/linux/linux-yocto-4.19.8/1500-drm-amd-display-Pass-app_tf-by-value-rather-than-by-.patch new file mode 100644 index 00000000..22919771 --- /dev/null +++ b/common/recipes-kernel/linux/linux-yocto-4.19.8/1500-drm-amd-display-Pass-app_tf-by-value-rather-than-by-.patch @@ -0,0 +1,95 @@ +From 8ad6275aa89f52fc35414a48ae6f29002f529c15 Mon Sep 17 00:00:00 2001 +From: Nathan Chancellor <natechancellor@gmail.com> +Date: Mon, 10 Dec 2018 16:42:01 -0700 +Subject: [PATCH 1500/2940] drm/amd/display: Pass app_tf by value rather than + by reference + +Clang warns when an expression that equals zero is used as a null +pointer constant (in lieu of NULL): + +drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm.c:4435:3: +warning: expression which evaluates to zero treated as a null pointer +constant of type 'const enum color_transfer_func *' +[-Wnon-literal-null-conversion] + TRANSFER_FUNC_UNKNOWN, + ^~~~~~~~~~~~~~~~~~~~~ +1 warning generated. + +This warning is caused by commit bb47de736661 ("drm/amdgpu: Set FreeSync +state using drm VRR properties") and it could be solved by using NULL +instead of TRANSFER_FUNC_UNKNOWN or casting TRANSFER_FUNC_UNKNOWN as a +pointer. However, after looking into it, there doesn't appear to be a +good reason to pass app_tf by reference as it is never mutated along the +way. This is the only code path in which app_tf is used: + +mod_freesync_build_vrr_infopacket -> + build_vrr_infopacket_v2 -> + build_vrr_infopacket_fs2_data + +Neither mod_freesync_build_vrr_infopacket or build_vrr_infopacket_v2 +modify app_tf's value and build_vrr_infopacket_fs2_data expects just +the value so we can avoid dereferencing anything by just passing in +app_tf's value to mod_freesync_build_vrr_infopacket and +build_vrr_infopacket_v2. + +There is no functional change because build_vrr_infopacket_fs2_data +doesn't do anything if TRANSFER_FUNC_UNKNOWN is passed to it, the same +as not calling build_vrr_infopacket_fs2_data at all like before this +change when NULL was used for app_tf. + +Reviewed-by: Harry Wentland <harry.wentland@amd.com> +Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> +Signed-off-by: Alex Deucher <alexander.deucher@amd.com> +--- + drivers/gpu/drm/amd/display/modules/freesync/freesync.c | 7 +++---- + drivers/gpu/drm/amd/display/modules/inc/mod_freesync.h | 2 +- + 2 files changed, 4 insertions(+), 5 deletions(-) + +diff --git a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c +index 94a84bc57c7a..bfd27f10879e 100644 +--- a/drivers/gpu/drm/amd/display/modules/freesync/freesync.c ++++ b/drivers/gpu/drm/amd/display/modules/freesync/freesync.c +@@ -724,7 +724,7 @@ static void build_vrr_infopacket_v1(enum signal_type signal, + + static void build_vrr_infopacket_v2(enum signal_type signal, + const struct mod_vrr_params *vrr, +- const enum color_transfer_func *app_tf, ++ enum color_transfer_func app_tf, + struct dc_info_packet *infopacket) + { + unsigned int payload_size = 0; +@@ -732,8 +732,7 @@ static void build_vrr_infopacket_v2(enum signal_type signal, + build_vrr_infopacket_header_v2(signal, infopacket, &payload_size); + build_vrr_infopacket_data(vrr, infopacket); + +- if (app_tf != NULL) +- build_vrr_infopacket_fs2_data(*app_tf, infopacket); ++ build_vrr_infopacket_fs2_data(app_tf, infopacket); + + build_vrr_infopacket_checksum(&payload_size, infopacket); + +@@ -757,7 +756,7 @@ void mod_freesync_build_vrr_infopacket(struct mod_freesync *mod_freesync, + const struct dc_stream_state *stream, + const struct mod_vrr_params *vrr, + enum vrr_packet_type packet_type, +- const enum color_transfer_func *app_tf, ++ enum color_transfer_func app_tf, + struct dc_info_packet *infopacket) + { + /* SPD info packet for FreeSync +diff --git a/drivers/gpu/drm/amd/display/modules/inc/mod_freesync.h b/drivers/gpu/drm/amd/display/modules/inc/mod_freesync.h +index 4222e403b151..dcef85994c45 100644 +--- a/drivers/gpu/drm/amd/display/modules/inc/mod_freesync.h ++++ b/drivers/gpu/drm/amd/display/modules/inc/mod_freesync.h +@@ -145,7 +145,7 @@ void mod_freesync_build_vrr_infopacket(struct mod_freesync *mod_freesync, + const struct dc_stream_state *stream, + const struct mod_vrr_params *vrr, + enum vrr_packet_type packet_type, +- const enum color_transfer_func *app_tf, ++ enum color_transfer_func app_tf, + struct dc_info_packet *infopacket); + + void mod_freesync_build_vrr_params(struct mod_freesync *mod_freesync, +-- +2.17.1 + |