diff mbox series

[v6,3/4] drm/msm/dp: parser link-frequencies as property of dp_out endpoint

Message ID 1669852310-22360-4-git-send-email-quic_khsieh@quicinc.com (mailing list archive)
State New, archived
Headers show
Series Add data-lanes and link-frequencies to dp_out endpoint | expand

Commit Message

Kuogee Hsieh Nov. 30, 2022, 11:51 p.m. UTC 
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

Signed-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
---
 drivers/gpu/drm/msm/dp/dp_parser.c | 16 ++++++++++++++++
 drivers/gpu/drm/msm/dp/dp_parser.h |  2 ++
 2 files changed, 18 insertions(+)

Comments

Dmitry Baryshkov Dec. 1, 2022, 12:26 a.m. UTC | #1 
On 01/12/2022 01:51, 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
> 
> Signed-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
> ---
>   drivers/gpu/drm/msm/dp/dp_parser.c | 16 ++++++++++++++++
>   drivers/gpu/drm/msm/dp/dp_parser.h |  2 ++
>   2 files changed, 18 insertions(+)
> 
> diff --git a/drivers/gpu/drm/msm/dp/dp_parser.c b/drivers/gpu/drm/msm/dp/dp_parser.c
> index b06ff60..2006341 100644
> --- a/drivers/gpu/drm/msm/dp/dp_parser.c
> +++ b/drivers/gpu/drm/msm/dp/dp_parser.c
> @@ -95,6 +95,7 @@ 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;
>   
>   	/*
> @@ -103,6 +104,7 @@ static int dp_parser_misc(struct dp_parser *parser)
>   	cnt = drm_of_get_data_lanes_count(of_node, 1, DP_MAX_NUM_DP_LANES);
>   	if (cnt > 0) {
>   		parser->max_dp_lanes = cnt;
> +		parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 540000 khz */
>   		return 0;
>   	}
>   
> @@ -116,8 +118,22 @@ static int dp_parser_misc(struct dp_parser *parser)
>   			parser->max_dp_lanes = DP_MAX_NUM_DP_LANES; /* 4 lanes */
>   		else
>   			parser->max_dp_lanes = cnt;
> +
> +		cnt = of_property_count_u64_elems(endpoint, "link-frequencies");
> +		if (cnt < 0) {
> +			parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 540000 khz */
> +		} else {
> +			if (cnt > DP_MAX_NUM_DP_LANES)
> +				cnt = DP_MAX_NUM_DP_LANES;

Why are you comparing the number of link frequencies with the number of 
lanes? You don't need the comparison at all.

> +
> +			of_property_read_u64_index(endpoint, "link-frequencies",
> +							cnt - 1, &frequency);

Checking of the return value?

> +
> +			parser->max_dp_link_rate = (frequency / 1000); /* kbits */
> +		}
>   	} else {
>   		parser->max_dp_lanes = DP_MAX_NUM_DP_LANES; /* 4 lanes */
> +		parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 540000 khz */

Instead of having all the nested if's and setting of max_dp_link rate in 
several branches, please add a function that returns either a valid rate 
or an error. Then you can simply check the result of that function and 
set the default.

>   	}
>   
>   	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       540000
>   
>   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);
kernel test robot Dec. 1, 2022, 9:13 p.m. UTC | #2 
Hi Kuogee,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on drm-misc/drm-misc-next]
[also build test ERROR on drm/drm-next robh/for-next linus/master v6.1-rc7 next-20221201]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Kuogee-Hsieh/Add-data-lanes-and-link-frequencies-to-dp_out-endpoint/20221201-075329
base:   git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link:    https://lore.kernel.org/r/1669852310-22360-4-git-send-email-quic_khsieh%40quicinc.com
patch subject: [PATCH v6 3/4] drm/msm/dp: parser link-frequencies as property of dp_out endpoint
config: arm-defconfig
compiler: arm-linux-gnueabi-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/ed62a08e7f8c0bd3db26756b50852e96e0d5ebd7
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Kuogee-Hsieh/Add-data-lanes-and-link-frequencies-to-dp_out-endpoint/20221201-075329
        git checkout ed62a08e7f8c0bd3db26756b50852e96e0d5ebd7
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>, old ones prefixed by <<):

>> ERROR: modpost: "__aeabi_uldivmod" [drivers/gpu/drm/msm/msm.ko] undefined!
kernel test robot Dec. 1, 2022, 9:44 p.m. UTC | #3 
Hi Kuogee,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on drm-misc/drm-misc-next]
[also build test ERROR on drm/drm-next robh/for-next linus/master v6.1-rc7 next-20221201]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Kuogee-Hsieh/Add-data-lanes-and-link-frequencies-to-dp_out-endpoint/20221201-075329
base:   git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link:    https://lore.kernel.org/r/1669852310-22360-4-git-send-email-quic_khsieh%40quicinc.com
patch subject: [PATCH v6 3/4] drm/msm/dp: parser link-frequencies as property of dp_out endpoint
config: m68k-allmodconfig
compiler: m68k-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/ed62a08e7f8c0bd3db26756b50852e96e0d5ebd7
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Kuogee-Hsieh/Add-data-lanes-and-link-frequencies-to-dp_out-endpoint/20221201-075329
        git checkout ed62a08e7f8c0bd3db26756b50852e96e0d5ebd7
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=m68k SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>, old ones prefixed by <<):

>> ERROR: modpost: "__udivdi3" [drivers/gpu/drm/msm/msm.ko] undefined!
diff mbox series

Patch

diff --git a/drivers/gpu/drm/msm/dp/dp_parser.c b/drivers/gpu/drm/msm/dp/dp_parser.c
index b06ff60..2006341 100644
--- a/drivers/gpu/drm/msm/dp/dp_parser.c
+++ b/drivers/gpu/drm/msm/dp/dp_parser.c
@@ -95,6 +95,7 @@  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;
 
 	/*
@@ -103,6 +104,7 @@  static int dp_parser_misc(struct dp_parser *parser)
 	cnt = drm_of_get_data_lanes_count(of_node, 1, DP_MAX_NUM_DP_LANES);
 	if (cnt > 0) {
 		parser->max_dp_lanes = cnt;
+		parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 540000 khz */
 		return 0;
 	}
 
@@ -116,8 +118,22 @@  static int dp_parser_misc(struct dp_parser *parser)
 			parser->max_dp_lanes = DP_MAX_NUM_DP_LANES; /* 4 lanes */
 		else
 			parser->max_dp_lanes = cnt;
+
+		cnt = of_property_count_u64_elems(endpoint, "link-frequencies");
+		if (cnt < 0) {
+			parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 540000 khz */
+		} else {
+			if (cnt > DP_MAX_NUM_DP_LANES)
+				cnt = DP_MAX_NUM_DP_LANES;
+
+			of_property_read_u64_index(endpoint, "link-frequencies",
+							cnt - 1, &frequency);
+
+			parser->max_dp_link_rate = (frequency / 1000); /* kbits */
+		}
 	} else {
 		parser->max_dp_lanes = DP_MAX_NUM_DP_LANES; /* 4 lanes */
+		parser->max_dp_link_rate = DP_LINK_RATE_HBR2; /* 540000 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_LANES	4
+#define DP_LINK_RATE_HBR2       540000
 
 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);