Re: [Freedreno] [PATCH v8 4/5] drm/msm/dp: parser link-frequencies as property of dp_out endpoint
On 5 December 2022 22:14:29 GMT+03:00, Kuogee Hsieh
wrote:
>Add capability to parser and retrieve max DP link supported rate from
>link-frequencies property of dp_out endpoint.
>
>Changes in v6:
>-- second patch after split parser patch into two patches
>
>Changes in v7:
>-- without checking cnt against DP_MAX_NUM_DP_LANES to retrieve link rate
>
>Signed-off-by: Kuogee Hsieh
>---
> drivers/gpu/drm/msm/dp/dp_parser.c | 19 +--
> drivers/gpu/drm/msm/dp/dp_parser.h | 2 ++
> 2 files changed, 19 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/gpu/drm/msm/dp/dp_parser.c
>b/drivers/gpu/drm/msm/dp/dp_parser.c
>index b5f7e70..037dad8 100644
>--- a/drivers/gpu/drm/msm/dp/dp_parser.c
>+++ b/drivers/gpu/drm/msm/dp/dp_parser.c
>@@ -94,15 +94,28 @@ static int dp_parser_ctrl_res(struct dp_parser *parser)
> static int dp_parser_misc(struct dp_parser *parser)
> {
> struct device_node *of_node = parser->pdev->dev.of_node;
>+ struct device_node *endpoint;
>+ u64 frequency;
> int cnt;
>
> /*
>* data-lanes is the property of dp_out endpoint
>*/
> cnt = drm_of_get_data_lanes_count_ep(of_node, 1, 0, 1,
> DP_MAX_NUM_DP_LANES);
>- if (cnt > 0)
>+ if (cnt > 0) {
> parser->max_dp_lanes = cnt;
>- else {
>+
>+ endpoint = of_graph_get_endpoint_by_regs(of_node, 1, 0); /*
>port@1 */
>+ cnt = of_property_count_u64_elems(endpoint, "link-frequencies");
Missing of_node_put()
>+ if (cnt > 0) {
>+ of_property_read_u64_index(endpoint, "link-frequencies",
>+ cnt - 1, );
>+ frequency /= 10;/* from symbol rate to link
>rate */
>+ parser->max_dp_link_rate = (frequency / 1000); /* kbits
>*/
>+ } else {
>+ parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 54
>khz */
>+ }
>+ } else {
> /*
>* legacy code, data-lanes is the property of mdss_dp node
>*/
>@@ -111,6 +124,8 @@ static int dp_parser_misc(struct dp_parser *parser)
> parser->max_dp_lanes = cnt;
> else
> parser->max_dp_lanes = DP_MAX_NUM_DP_LANES; /* 4 lanes
> */
>+
>+ parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 54 khz */
Please, don't mix the dp lanes and dp link rate code. It would be much easier
to read. And you can remove the duplicate assignment statements too.
> }
>
> return 0;
>diff --git a/drivers/gpu/drm/msm/dp/dp_parser.h
>b/drivers/gpu/drm/msm/dp/dp_parser.h
>index 866c1a8..3ddf639 100644
>--- a/drivers/gpu/drm/msm/dp/dp_parser.h
>+++ b/drivers/gpu/drm/msm/dp/dp_parser.h
>@@ -15,6 +15,7 @@
> #define DP_LABEL "MDSS DP DISPLAY"
> #define DP_MAX_PIXEL_CLK_KHZ 675000
> #define DP_MAX_NUM_DP_LANES 4
>+#define DP_LINK_RATE_HBR2 54
>
> enum dp_pm_type {
> DP_CORE_PM,
>@@ -119,6 +120,7 @@ struct dp_parser {
> struct dp_io io;
> struct dp_display_data disp_data;
> u32 max_dp_lanes;
>+ u32 max_dp_link_rate;
> struct drm_bridge *next_bridge;
>
> int (*parse)(struct dp_parser *parser);
--
With best wishes
Dmitry
[Freedreno] [PATCH v8 4/5] drm/msm/dp: parser link-frequencies as property of dp_out endpoint
Add capability to parser and retrieve max DP link supported rate from
link-frequencies property of dp_out endpoint.
Changes in v6:
-- second patch after split parser patch into two patches
Changes in v7:
-- without checking cnt against DP_MAX_NUM_DP_LANES to retrieve link rate
Signed-off-by: Kuogee Hsieh
---
drivers/gpu/drm/msm/dp/dp_parser.c | 19 +--
drivers/gpu/drm/msm/dp/dp_parser.h | 2 ++
2 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/msm/dp/dp_parser.c
b/drivers/gpu/drm/msm/dp/dp_parser.c
index b5f7e70..037dad8 100644
--- a/drivers/gpu/drm/msm/dp/dp_parser.c
+++ b/drivers/gpu/drm/msm/dp/dp_parser.c
@@ -94,15 +94,28 @@ static int dp_parser_ctrl_res(struct dp_parser *parser)
static int dp_parser_misc(struct dp_parser *parser)
{
struct device_node *of_node = parser->pdev->dev.of_node;
+ struct device_node *endpoint;
+ u64 frequency;
int cnt;
/*
* data-lanes is the property of dp_out endpoint
*/
cnt = drm_of_get_data_lanes_count_ep(of_node, 1, 0, 1,
DP_MAX_NUM_DP_LANES);
- if (cnt > 0)
+ if (cnt > 0) {
parser->max_dp_lanes = cnt;
- else {
+
+ endpoint = of_graph_get_endpoint_by_regs(of_node, 1, 0); /*
port@1 */
+ cnt = of_property_count_u64_elems(endpoint, "link-frequencies");
+ if (cnt > 0) {
+ of_property_read_u64_index(endpoint, "link-frequencies",
+ cnt - 1, );
+ frequency /= 10;/* from symbol rate to link
rate */
+ parser->max_dp_link_rate = (frequency / 1000); /* kbits
*/
+ } else {
+ parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 54
khz */
+ }
+ } else {
/*
* legacy code, data-lanes is the property of mdss_dp node
*/
@@ -111,6 +124,8 @@ static int dp_parser_misc(struct dp_parser *parser)
parser->max_dp_lanes = cnt;
else
parser->max_dp_lanes = DP_MAX_NUM_DP_LANES; /* 4 lanes
*/
+
+ parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 54 khz */
}
return 0;
diff --git a/drivers/gpu/drm/msm/dp/dp_parser.h
b/drivers/gpu/drm/msm/dp/dp_parser.h
index 866c1a8..3ddf639 100644
--- a/drivers/gpu/drm/msm/dp/dp_parser.h
+++ b/drivers/gpu/drm/msm/dp/dp_parser.h
@@ -15,6 +15,7 @@
#define DP_LABEL "MDSS DP DISPLAY"
#define DP_MAX_PIXEL_CLK_KHZ 675000
#define DP_MAX_NUM_DP_LANES4
+#define DP_LINK_RATE_HBR2 54
enum dp_pm_type {
DP_CORE_PM,
@@ -119,6 +120,7 @@ struct dp_parser {
struct dp_io io;
struct dp_display_data disp_data;
u32 max_dp_lanes;
+ u32 max_dp_link_rate;
struct drm_bridge *next_bridge;
int (*parse)(struct dp_parser *parser);
--
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