This is a note to let you know that I've just added the patch titled drm/amd/display: Fix debugfs link_settings entry to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-amd-display-fix-debugfs-link_settings-entry.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e799a3f5b05224e80a8118b1988983fc5ff21ab7 Author: Fangzhi Zuo <Jerry.Zuo@xxxxxxx> Date: Tue Mar 9 11:22:36 2021 -0500 drm/amd/display: Fix debugfs link_settings entry [ Upstream commit c006a1c00de29e8cdcde1d0254ac23433ed3fee9 ] 1. Catch invalid link_rate and link_count settings 2. Call dc interface to overwrite preferred link settings, and wait until next stream update to apply the new settings. Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx> Signed-off-by: Fangzhi Zuo <Jerry.Zuo@xxxxxxx> Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@xxxxxxx> Acked-by: Solomon Chiu <solomon.chiu@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c index 8cd646eef096..e02a55fc1382 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c @@ -150,7 +150,7 @@ static int parse_write_buffer_into_params(char *wr_buf, uint32_t wr_buf_size, * * --- to get dp configuration * - * cat link_settings + * cat /sys/kernel/debug/dri/0/DP-x/link_settings * * It will list current, verified, reported, preferred dp configuration. * current -- for current video mode @@ -163,7 +163,7 @@ static int parse_write_buffer_into_params(char *wr_buf, uint32_t wr_buf_size, * echo <lane_count> <link_rate> > link_settings * * for example, to force to 2 lane, 2.7GHz, - * echo 4 0xa > link_settings + * echo 4 0xa > /sys/kernel/debug/dri/0/DP-x/link_settings * * spread_spectrum could not be changed dynamically. * @@ -171,7 +171,7 @@ static int parse_write_buffer_into_params(char *wr_buf, uint32_t wr_buf_size, * done. please check link settings after force operation to see if HW get * programming. * - * cat link_settings + * cat /sys/kernel/debug/dri/0/DP-x/link_settings * * check current and preferred settings. * @@ -255,7 +255,7 @@ static ssize_t dp_link_settings_write(struct file *f, const char __user *buf, int max_param_num = 2; uint8_t param_nums = 0; long param[2]; - bool valid_input = false; + bool valid_input = true; if (size == 0) return -EINVAL; @@ -282,9 +282,9 @@ static ssize_t dp_link_settings_write(struct file *f, const char __user *buf, case LANE_COUNT_ONE: case LANE_COUNT_TWO: case LANE_COUNT_FOUR: - valid_input = true; break; default: + valid_input = false; break; } @@ -294,9 +294,9 @@ static ssize_t dp_link_settings_write(struct file *f, const char __user *buf, case LINK_RATE_RBR2: case LINK_RATE_HIGH2: case LINK_RATE_HIGH3: - valid_input = true; break; default: + valid_input = false; break; } @@ -310,10 +310,11 @@ static ssize_t dp_link_settings_write(struct file *f, const char __user *buf, * spread spectrum will not be changed */ prefer_link_settings.link_spread = link->cur_link_settings.link_spread; + prefer_link_settings.use_link_rate_set = false; prefer_link_settings.lane_count = param[0]; prefer_link_settings.link_rate = param[1]; - dc_link_set_preferred_link_settings(dc, &prefer_link_settings, link); + dc_link_set_preferred_training_settings(dc, &prefer_link_settings, NULL, link, true); kfree(wr_buf); return size;