6.14-stable review patch. If anyone has any objections, please let me know.
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From: Marijn Suijten marijn.suijten@somainline.org
[ Upstream commit 14ad809ceb66d0874cbe4bd5ca9edf0de8d9ad96 ]
When configuring the timing of DSI hosts (interfaces) in dsi_timing_setup() all values written to registers are taking bonded-mode into account by dividing the original mode width by 2 (half the data is sent over each of the two DSI hosts), but the full width instead of the interface width is passed as hdisplay parameter to dsi_update_dsc_timing().
Currently only msm_dsc_get_slices_per_intf() is called within dsi_update_dsc_timing() with the `hdisplay` argument which clearly documents that it wants the width of a single interface (which, again, in bonded DSI mode is half the total width of the mode) resulting in all subsequent values to be completely off.
However, as soon as we start to pass the halved hdisplay into dsi_update_dsc_timing() we might as well discard msm_dsc_get_slices_per_intf() since the value it calculates is already available in dsc->slice_count which is per-interface by the current design of MSM DPU/DSI implementations and their use of the DRM DSC helpers.
Fixes: 08802f515c3c ("drm/msm/dsi: Add support for DSC configuration") Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Reviewed-by: Jessica Zhang quic_jesszhan@quicinc.com Signed-off-by: Marijn Suijten marijn.suijten@somainline.org Patchwork: https://patchwork.freedesktop.org/patch/637648/ Link: https://lore.kernel.org/r/20250217-drm-msm-initial-dualpipe-dsc-fixes-v3-1-9... Signed-off-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/msm/dsi/dsi_host.c | 8 ++++---- drivers/gpu/drm/msm/msm_dsc_helper.h | 11 ----------- 2 files changed, 4 insertions(+), 15 deletions(-)
diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c index 007311c21fdaa..42e100a8adca0 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -846,7 +846,7 @@ static void dsi_ctrl_enable(struct msm_dsi_host *msm_host, dsi_write(msm_host, REG_DSI_CPHY_MODE_CTRL, BIT(0)); }
-static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mode, u32 hdisplay) +static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mode) { struct drm_dsc_config *dsc = msm_host->dsc; u32 reg, reg_ctrl, reg_ctrl2; @@ -858,7 +858,7 @@ static void dsi_update_dsc_timing(struct msm_dsi_host *msm_host, bool is_cmd_mod /* first calculate dsc parameters and then program * compress mode registers */ - slice_per_intf = msm_dsc_get_slices_per_intf(dsc, hdisplay); + slice_per_intf = dsc->slice_count;
total_bytes_per_intf = dsc->slice_chunk_size * slice_per_intf; bytes_per_pkt = dsc->slice_chunk_size; /* * slice_per_pkt; */ @@ -991,7 +991,7 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi)
if (msm_host->mode_flags & MIPI_DSI_MODE_VIDEO) { if (msm_host->dsc) - dsi_update_dsc_timing(msm_host, false, mode->hdisplay); + dsi_update_dsc_timing(msm_host, false);
dsi_write(msm_host, REG_DSI_ACTIVE_H, DSI_ACTIVE_H_START(ha_start) | @@ -1012,7 +1012,7 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi) DSI_ACTIVE_VSYNC_VPOS_END(vs_end)); } else { /* command mode */ if (msm_host->dsc) - dsi_update_dsc_timing(msm_host, true, mode->hdisplay); + dsi_update_dsc_timing(msm_host, true);
/* image data and 1 byte write_memory_start cmd */ if (!msm_host->dsc) diff --git a/drivers/gpu/drm/msm/msm_dsc_helper.h b/drivers/gpu/drm/msm/msm_dsc_helper.h index b9049fe1e2790..63f95523b2cbb 100644 --- a/drivers/gpu/drm/msm/msm_dsc_helper.h +++ b/drivers/gpu/drm/msm/msm_dsc_helper.h @@ -12,17 +12,6 @@ #include <linux/math.h> #include <drm/display/drm_dsc_helper.h>
-/** - * msm_dsc_get_slices_per_intf() - calculate number of slices per interface - * @dsc: Pointer to drm dsc config struct - * @intf_width: interface width in pixels - * Returns: Integer representing the number of slices for the given interface - */ -static inline u32 msm_dsc_get_slices_per_intf(const struct drm_dsc_config *dsc, u32 intf_width) -{ - return DIV_ROUND_UP(intf_width, dsc->slice_width); -} - /** * msm_dsc_get_bytes_per_line() - calculate bytes per line * @dsc: Pointer to drm dsc config struct