2022-04-05 03:32:40

by Grigory Vasilyev

[permalink] [raw]
Subject: [PATCH] drm/amdgpu: Junk code

Variable igp_lane_info always is 0. 0 & any value = 0 and false.
In this way, all сonditional statements will false.
Therefore, it is not clear what this code does.

Signed-off-by: Grigory Vasilyev <[email protected]>
---
.../gpu/drm/amd/amdgpu/atombios_encoders.c | 21 -------------------
1 file changed, 21 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
index 2b0cc793291c..100bad2f5901 100644
--- a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
+++ b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
@@ -769,7 +769,6 @@ amdgpu_atombios_encoder_setup_dig_transmitter(struct drm_encoder *encoder, int a
int dp_clock = 0;
int dp_lane_count = 0;
int connector_object_id = 0;
- int igp_lane_info = 0;
int dig_encoder = dig->dig_encoder;
int hpd_id = AMDGPU_HPD_NONE;

@@ -852,26 +851,6 @@ amdgpu_atombios_encoder_setup_dig_transmitter(struct drm_encoder *encoder, int a
else
args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_DIG1_ENCODER;

- if ((adev->flags & AMD_IS_APU) &&
- (amdgpu_encoder->encoder_id == ENCODER_OBJECT_ID_INTERNAL_UNIPHY)) {
- if (is_dp ||
- !amdgpu_dig_monitor_is_duallink(encoder, amdgpu_encoder->pixel_clock)) {
- if (igp_lane_info & 0x1)
- args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_0_3;
- else if (igp_lane_info & 0x2)
- args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_4_7;
- else if (igp_lane_info & 0x4)
- args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_8_11;
- else if (igp_lane_info & 0x8)
- args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_12_15;
- } else {
- if (igp_lane_info & 0x3)
- args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_0_7;
- else if (igp_lane_info & 0xc)
- args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_8_15;
- }
- }
-
if (dig->linkb)
args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LINKB;
else
--
2.35.1


2022-04-06 10:15:48

by Alex Deucher

[permalink] [raw]
Subject: Re: [PATCH] drm/amdgpu: Junk code

On Tue, Apr 5, 2022 at 5:07 AM Grigory Vasilyev <[email protected]> wrote:
>
> Variable igp_lane_info always is 0. 0 & any value = 0 and false.
> In this way, all сonditional statements will false.
> Therefore, it is not clear what this code does.

It was leftover from when the code was ported from radeon. The igp
lane info was available from the vbios on older APUs. It's not
relevant on any asics supported by amdgpu. I've applied the patch and
clarified the commit message.

Thanks,

Alex

>
> Signed-off-by: Grigory Vasilyev <[email protected]>
> ---
> .../gpu/drm/amd/amdgpu/atombios_encoders.c | 21 -------------------
> 1 file changed, 21 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
> index 2b0cc793291c..100bad2f5901 100644
> --- a/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
> +++ b/drivers/gpu/drm/amd/amdgpu/atombios_encoders.c
> @@ -769,7 +769,6 @@ amdgpu_atombios_encoder_setup_dig_transmitter(struct drm_encoder *encoder, int a
> int dp_clock = 0;
> int dp_lane_count = 0;
> int connector_object_id = 0;
> - int igp_lane_info = 0;
> int dig_encoder = dig->dig_encoder;
> int hpd_id = AMDGPU_HPD_NONE;
>
> @@ -852,26 +851,6 @@ amdgpu_atombios_encoder_setup_dig_transmitter(struct drm_encoder *encoder, int a
> else
> args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_DIG1_ENCODER;
>
> - if ((adev->flags & AMD_IS_APU) &&
> - (amdgpu_encoder->encoder_id == ENCODER_OBJECT_ID_INTERNAL_UNIPHY)) {
> - if (is_dp ||
> - !amdgpu_dig_monitor_is_duallink(encoder, amdgpu_encoder->pixel_clock)) {
> - if (igp_lane_info & 0x1)
> - args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_0_3;
> - else if (igp_lane_info & 0x2)
> - args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_4_7;
> - else if (igp_lane_info & 0x4)
> - args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_8_11;
> - else if (igp_lane_info & 0x8)
> - args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_12_15;
> - } else {
> - if (igp_lane_info & 0x3)
> - args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_0_7;
> - else if (igp_lane_info & 0xc)
> - args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LANE_8_15;
> - }
> - }
> -
> if (dig->linkb)
> args.v1.ucConfig |= ATOM_TRANSMITTER_CONFIG_LINKB;
> else
> --
> 2.35.1
>