Allow supported link rate to be limited to the value specified at
dtsi. If it is not specified, then link rate is derived from dpcd
directly. Below are examples,
link-rate = <162000> for max link rate limited at 1.62G
link-rate = <270000> for max link rate limited at 2.7G
link-rate = <540000> for max link rate limited at 5.4G
link-rate = <810000> for max link rate limited at 8.1G
Changes in V2:
-- allow supported max link rate specified from dtsi
Signed-off-by: Kuogee Hsieh <khs...@codeaurora.org>
---
drivers/gpu/drm/msm/dp/dp_display.c | 1 +
drivers/gpu/drm/msm/dp/dp_panel.c | 7 ++++---
drivers/gpu/drm/msm/dp/dp_panel.h | 1 +
drivers/gpu/drm/msm/dp/dp_parser.c | 13 +++++++++++++
drivers/gpu/drm/msm/dp/dp_parser.h | 1 +
5 files changed, 20 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c
b/drivers/gpu/drm/msm/dp/dp_display.c
index 5a39da6..f633ba6 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -322,6 +322,7 @@ static int dp_display_process_hpd_high(struct
dp_display_private *dp)
struct edid *edid;
dp->panel->max_dp_lanes = dp->parser->max_dp_lanes;
+ dp->panel->max_link_rate = dp->parser->max_link_rate;
rc = dp_panel_read_sink_caps(dp->panel, dp->dp_display.connector);
if (rc)
diff --git a/drivers/gpu/drm/msm/dp/dp_panel.c
b/drivers/gpu/drm/msm/dp/dp_panel.c
index 9cc8166..be7f102 100644
--- a/drivers/gpu/drm/msm/dp/dp_panel.c
+++ b/drivers/gpu/drm/msm/dp/dp_panel.c
@@ -76,9 +76,10 @@ static int dp_panel_read_dpcd(struct dp_panel *dp_panel)
if (link_info->num_lanes > dp_panel->max_dp_lanes)
link_info->num_lanes = dp_panel->max_dp_lanes;
- /* Limit support upto HBR2 until HBR3 support is added */
- if (link_info->rate >= (drm_dp_bw_code_to_link_rate(DP_LINK_BW_5_4)))
- link_info->rate = drm_dp_bw_code_to_link_rate(DP_LINK_BW_5_4);
+ /* Limit support of ink rate if specified */
+ if (dp_panel->max_link_rate &&
+ (link_info->rate > dp_panel->max_link_rate))
+ link_info->rate = dp_panel->max_link_rate;
DRM_DEBUG_DP("version: %d.%d\n", major, minor);
DRM_DEBUG_DP("link_rate=%d\n", link_info->rate);
diff --git a/drivers/gpu/drm/msm/dp/dp_panel.h
b/drivers/gpu/drm/msm/dp/dp_panel.h
index 9023e5b..1876f5e 100644
--- a/drivers/gpu/drm/msm/dp/dp_panel.h
+++ b/drivers/gpu/drm/msm/dp/dp_panel.h
@@ -51,6 +51,7 @@ struct dp_panel {
u32 vic;
u32 max_pclk_khz;
u32 max_dp_lanes;
+ u32 max_link_rate;
u32 max_bw_code;
};
diff --git a/drivers/gpu/drm/msm/dp/dp_parser.c
b/drivers/gpu/drm/msm/dp/dp_parser.c
index 0519dd3..d8b6898 100644
--- a/drivers/gpu/drm/msm/dp/dp_parser.c
+++ b/drivers/gpu/drm/msm/dp/dp_parser.c
@@ -87,6 +87,8 @@ static int dp_parser_misc(struct dp_parser *parser)
struct device_node *of_node = parser->pdev->dev.of_node;
int len = 0;
const char *data_lane_property = "data-lanes";
+ const char *link_rate_property = "link-rate";
+ u32 rate = 0;
len = of_property_count_elems_of_size(of_node,
data_lane_property, sizeof(u32));
@@ -97,6 +99,17 @@ static int dp_parser_misc(struct dp_parser *parser)
}
parser->max_dp_lanes = len;
+
+ len = of_property_count_elems_of_size(of_node,
+ link_rate_property, sizeof(u32));
+
+ if (len == 1) {
+ of_property_read_u32_index(of_node,
+ link_rate_property, 0, &rate);
+
+ parser->max_link_rate = rate;
+ }
+
return 0;
}
diff --git a/drivers/gpu/drm/msm/dp/dp_parser.h
b/drivers/gpu/drm/msm/dp/dp_parser.h
index 34b4962..7046fce 100644
--- a/drivers/gpu/drm/msm/dp/dp_parser.h
+++ b/drivers/gpu/drm/msm/dp/dp_parser.h
@@ -116,6 +116,7 @@ struct dp_parser {
struct dp_display_data disp_data;
const struct dp_regulator_cfg *regulator_cfg;
u32 max_dp_lanes;
+ u32 max_link_rate;
int (*parse)(struct dp_parser *parser);
};
--
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