On Thu 18 Feb 14:55 CST 2021, Kuogee Hsieh wrote:
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 khsieh@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 &&
Make the parser always initialize max_link_rate to something reasonable and just compare against that here.
(link_info->rate > dp_panel->max_link_rate))
No need for the (), nor for line breaking this.
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";
There's no reason for stashing these in local variables.
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));
I'm afraid I don't see the reason for this, simply rely on the return value of of_property_read_u32(), i.e.
ret = of_property_read_u32(node, "link-rate", &rate); if (!ret) parser->max_link_rate = rate;
Or if you want to give it some default value:
rate = 1234; of_property_read_u32(node, "link-rate", &rate); Which either will overwrite the rate with the value of the property, or leave it untouched.
Regards, Bjorn
- 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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