[PATCH v8 17/29] drm/msm/dp: move link capabilities to dp_link
From: Yongxing Mou
Date: Tue Nov 10 2026 - 00:01:04 EST
Link rate, lane count and VSC SDP support describe capabilities of
the physical DP link rather than an individual panel.
While SST has only one panel per link, MST creates multiple stream
panels sharing the same upstream link. Keeping link capabilities in
struct msm_dp_panel would require each stream panel to maintain a copy
of the same link state, mixing shared link capabilities with per-panel
state.
Move the capabilities to struct msm_dp_link so that SST and MST use
the same link state. Rename link_info to link_caps to distinguish the
link capabilities from link_params used during link training.
Signed-off-by: Yongxing Mou <yongxing.mou@xxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/msm/dp/dp_ctrl.c | 6 +++---
drivers/gpu/drm/msm/dp/dp_debug.c | 6 +++---
drivers/gpu/drm/msm/dp/dp_display.c | 8 ++++----
drivers/gpu/drm/msm/dp/dp_link.h | 2 ++
drivers/gpu/drm/msm/dp/dp_panel.c | 22 ++++++++++++----------
drivers/gpu/drm/msm/dp/dp_panel.h | 2 --
6 files changed, 24 insertions(+), 22 deletions(-)
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index 06c370c5ea09d..82fb3ae750f42 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1750,7 +1750,7 @@ static int msm_dp_ctrl_link_lane_down_shift(struct msm_dp_ctrl_private *ctrl,
return -1;
ctrl->link->link_params.num_lanes /= 2;
- ctrl->link->link_params.rate = panel->link_info.rate;
+ ctrl->link->link_params.rate = ctrl->link->link_caps.rate;
ctrl->link->phy_params.p_level = 0;
ctrl->link->phy_params.v_level = 0;
@@ -2554,7 +2554,7 @@ int msm_dp_ctrl_on_link(struct msm_dp_ctrl *msm_dp_ctrl,
ctrl = container_of(msm_dp_ctrl, struct msm_dp_ctrl_private, msm_dp_ctrl);
- rate = panel->link_info.rate;
+ rate = ctrl->link->link_caps.rate;
pixel_rate = panel->msm_dp_mode.drm_mode.clock;
msm_dp_ctrl_core_clk_enable(&ctrl->msm_dp_ctrl);
@@ -2567,7 +2567,7 @@ int msm_dp_ctrl_on_link(struct msm_dp_ctrl *msm_dp_ctrl,
} else {
ctrl->link->link_params.rate = rate;
ctrl->link->link_params.num_lanes =
- panel->link_info.num_lanes;
+ ctrl->link->link_caps.num_lanes;
if (panel->msm_dp_mode.out_fmt_is_yuv_420)
pixel_rate >>= 1;
}
diff --git a/drivers/gpu/drm/msm/dp/dp_debug.c b/drivers/gpu/drm/msm/dp/dp_debug.c
index 00fb1a7ba40ed..2a9ce77843bba 100644
--- a/drivers/gpu/drm/msm/dp/dp_debug.c
+++ b/drivers/gpu/drm/msm/dp/dp_debug.c
@@ -38,11 +38,11 @@ static int msm_dp_debug_show(struct seq_file *seq, void *p)
seq_printf(seq, "\tname = %s\n", DEBUG_NAME);
seq_printf(seq, "\tdrm_dp_link\n\t\trate = %u\n",
- debug->panel->link_info.rate);
+ debug->link->link_caps.rate);
seq_printf(seq, "\t\tnum_lanes = %u\n",
- debug->panel->link_info.num_lanes);
+ debug->link->link_caps.num_lanes);
seq_printf(seq, "\t\tcapabilities = %lu\n",
- debug->panel->link_info.capabilities);
+ debug->link->link_caps.capabilities);
seq_printf(seq, "\tdp_panel_info:\n\t\tactive = %dx%d\n",
drm_mode->hdisplay,
drm_mode->vdisplay);
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 9449ef692189c..1d8eef466e797 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -315,7 +315,7 @@ static int msm_dp_display_process_hpd_high(struct msm_dp_display_private *dp)
* set sink to normal operation mode -- D0
* before dpcd read
*/
- msm_dp_link_psm_config(dp->link, &dp->panel->link_info, false);
+ msm_dp_link_psm_config(dp->link, &dp->link->link_caps, false);
msm_dp_link_reset_phy_params_vx_px(dp->link);
@@ -813,7 +813,7 @@ enum drm_mode_status msm_dp_display_mode_valid(struct msm_dp *dp,
}
msm_dp_display = container_of(dp, struct msm_dp_display_private, msm_dp_display);
- link_info = &msm_dp_display->panel->link_info;
+ link_info = &msm_dp_display->link->link_caps;
is_yuv_420 = drm_mode_is_420_only(&dp->connector->display_info, mode);
@@ -821,7 +821,7 @@ enum drm_mode_status msm_dp_display_mode_valid(struct msm_dp *dp,
* YUV 420 is carried over DP by signalling the colorimetry through a
* VSC SDP, so a 420-only mode cannot be driven without VSC SDP support.
*/
- if (is_yuv_420 && !msm_dp_display->panel->vsc_sdp_supported)
+ if (is_yuv_420 && !msm_dp_display->link->vsc_sdp_supported)
return MODE_NO_420;
link_pclk_khz = is_yuv_420 ? mode_pclk_khz / 2 : mode_pclk_khz;
@@ -1653,7 +1653,7 @@ void msm_dp_display_unprepare(struct msm_dp *msm_dp_display)
/* dongle is still connected but sinks are disconnected */
if (dp->link->sink_count == 0)
- msm_dp_link_psm_config(dp->link, &dp->panel->link_info, true);
+ msm_dp_link_psm_config(dp->link, &dp->link->link_caps, true);
msm_dp_ctrl_off_link(dp->ctrl, dp->panel);
diff --git a/drivers/gpu/drm/msm/dp/dp_link.h b/drivers/gpu/drm/msm/dp/dp_link.h
index 76125e9c07e9c..80116d5c58be1 100644
--- a/drivers/gpu/drm/msm/dp/dp_link.h
+++ b/drivers/gpu/drm/msm/dp/dp_link.h
@@ -75,7 +75,9 @@ struct msm_dp_link {
struct msm_dp_link_test_video test_video;
struct msm_dp_link_test_audio test_audio;
struct msm_dp_link_phy_params phy_params;
+ struct msm_dp_link_info link_caps;
struct msm_dp_link_info link_params;
+ bool vsc_sdp_supported;
u32 lane_map[DP_MAX_NUM_DP_LANES];
u32 max_dp_lanes;
diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c b/drivers/gpu/drm/msm/dp/dp_panel.c
index bc7bad5ca3b18..dd650b3dc9172 100644
--- a/drivers/gpu/drm/msm/dp/dp_panel.c
+++ b/drivers/gpu/drm/msm/dp/dp_panel.c
@@ -193,13 +193,14 @@ static int msm_dp_panel_read_dpcd(struct msm_dp_panel *msm_dp_panel)
if (rc)
return rc;
- msm_dp_panel->vsc_sdp_supported = drm_dp_vsc_sdp_supported(panel->aux, dpcd);
- link_info = &msm_dp_panel->link_info;
+ link = panel->link;
+ link->vsc_sdp_supported = drm_dp_vsc_sdp_supported(panel->aux, dpcd);
+ link_info = &link->link_caps;
+ memset(link_info, 0, sizeof(*link_info));
link_info->revision = dpcd[DP_DPCD_REV];
major = (link_info->revision >> 4) & 0x0f;
minor = link_info->revision & 0x0f;
- link = panel->link;
drm_dbg_dp(panel->drm_dev, "max_lanes=%d max_link_rate=%d\n",
link->max_dp_lanes, link->max_dp_link_rate);
@@ -308,13 +309,15 @@ static int msm_dp_panel_read_dpcd(struct msm_dp_panel *msm_dp_panel)
static u32 msm_dp_panel_get_supported_bpp(struct msm_dp_panel *msm_dp_panel,
u32 mode_edid_bpp, u32 mode_pclk_khz)
{
+ struct msm_dp_panel_private *panel =
+ container_of(msm_dp_panel, struct msm_dp_panel_private, msm_dp_panel);
const struct msm_dp_link_info *link_info;
const u32 max_supported_bpp = 30, min_supported_bpp = 18;
u32 bpp, data_rate_khz;
bpp = min(mode_edid_bpp, max_supported_bpp);
- link_info = &msm_dp_panel->link_info;
+ link_info = &panel->link->link_caps;
data_rate_khz = link_info->num_lanes * link_info->rate * 8;
do {
@@ -346,12 +349,12 @@ int msm_dp_panel_read_link_caps(struct msm_dp_panel *msm_dp_panel,
return rc;
}
- bw_code = drm_dp_link_rate_to_bw_code(msm_dp_panel->link_info.rate);
+ bw_code = drm_dp_link_rate_to_bw_code(panel->link->link_caps.rate);
if (!is_link_rate_valid(bw_code) ||
- !is_lane_count_valid(msm_dp_panel->link_info.num_lanes) ||
+ !is_lane_count_valid(panel->link->link_caps.num_lanes) ||
(bw_code > msm_dp_panel->max_bw_code)) {
- DRM_ERROR("Illegal link rate=%d lane=%d\n", msm_dp_panel->link_info.rate,
- msm_dp_panel->link_info.num_lanes);
+ DRM_ERROR("Illegal link rate=%d lane=%d\n", panel->link->link_caps.rate,
+ panel->link->link_caps.num_lanes);
return -EINVAL;
}
@@ -770,7 +773,7 @@ int msm_dp_panel_init_panel_info(struct msm_dp_panel *msm_dp_panel,
!!(adjusted_mode->flags & DRM_MODE_FLAG_NHSYNC);
msm_dp_panel->msm_dp_mode.out_fmt_is_yuv_420 =
drm_mode_is_420_only(&msm_dp_panel->connector->display_info, adjusted_mode) &&
- msm_dp_panel->vsc_sdp_supported;
+ panel->link->vsc_sdp_supported;
drm_mode = &msm_dp_panel->msm_dp_mode.drm_mode;
@@ -837,4 +840,3 @@ struct msm_dp_panel *msm_dp_panel_get(struct device *dev, struct drm_dp_aux *aux
return msm_dp_panel;
}
-
diff --git a/drivers/gpu/drm/msm/dp/dp_panel.h b/drivers/gpu/drm/msm/dp/dp_panel.h
index 9f34cc9010d38..7cb9eaeb34c7f 100644
--- a/drivers/gpu/drm/msm/dp/dp_panel.h
+++ b/drivers/gpu/drm/msm/dp/dp_panel.h
@@ -47,12 +47,10 @@ struct msm_dp_panel {
u8 dpcd[DP_RECEIVER_CAP_SIZE];
u8 downstream_ports[DP_MAX_DOWNSTREAM_PORTS];
- struct msm_dp_link_info link_info;
struct drm_connector *connector;
struct msm_dp_display_mode msm_dp_mode;
struct msm_dp_panel_psr psr_cap;
bool video_test;
- bool vsc_sdp_supported;
u32 hw_revision;
enum msm_dp_stream_id stream_id;
--
2.43.0