* [PATCH] drm/msm/dp: skip checking LINK_STATUS_UPDATED bit
@ 2020-10-20 16:59 Kuogee Hsieh
2020-10-20 22:15 ` Stephen Boyd
0 siblings, 1 reply; 3+ messages in thread
From: Kuogee Hsieh @ 2020-10-20 16:59 UTC (permalink / raw)
To: robdclark, sean, swboyd
Cc: tanmay, abhinavk, aravindh, khsieh, airlied, daniel,
linux-arm-msm, dri-devel, freedreno, linux-kernel
No need to check LINK_STATuS_UPDATED bit before
return 6 bytes of link status during link training.
This patch also fix phy compliance test link rate
conversion error.
Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
---
drivers/gpu/drm/msm/dp/dp_ctrl.c | 20 ++++++--------------
drivers/gpu/drm/msm/dp/dp_link.c | 24 +++++++++++-------------
2 files changed, 17 insertions(+), 27 deletions(-)
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index 6bdaec778c4c..76e891c91c6e 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1061,23 +1061,15 @@ static bool dp_ctrl_train_pattern_set(struct dp_ctrl_private *ctrl,
static int dp_ctrl_read_link_status(struct dp_ctrl_private *ctrl,
u8 *link_status)
{
- int len = 0;
- u32 const offset = DP_LANE_ALIGN_STATUS_UPDATED - DP_LANE0_1_STATUS;
- u32 link_status_read_max_retries = 100;
-
- while (--link_status_read_max_retries) {
- len = drm_dp_dpcd_read_link_status(ctrl->aux,
- link_status);
- if (len != DP_LINK_STATUS_SIZE) {
- DRM_ERROR("DP link status read failed, err: %d\n", len);
- return len;
- }
+ int ret = 0, len;
- if (!(link_status[offset] & DP_LINK_STATUS_UPDATED))
- return 0;
+ len = drm_dp_dpcd_read_link_status(ctrl->aux, link_status);
+ if (len != DP_LINK_STATUS_SIZE) {
+ DRM_ERROR("DP link status read failed, err: %d\n", len);
+ ret = len;
}
- return -ETIMEDOUT;
+ return ret;
}
static int dp_ctrl_link_train_1(struct dp_ctrl_private *ctrl,
diff --git a/drivers/gpu/drm/msm/dp/dp_link.c b/drivers/gpu/drm/msm/dp/dp_link.c
index c811da515fb3..58d65daae3b3 100644
--- a/drivers/gpu/drm/msm/dp/dp_link.c
+++ b/drivers/gpu/drm/msm/dp/dp_link.c
@@ -773,7 +773,8 @@ static int dp_link_process_link_training_request(struct dp_link_private *link)
link->request.test_lane_count);
link->dp_link.link_params.num_lanes = link->request.test_lane_count;
- link->dp_link.link_params.rate = link->request.test_link_rate;
+ link->dp_link.link_params.rate =
+ drm_dp_bw_code_to_link_rate(link->request.test_link_rate);
return 0;
}
@@ -939,20 +940,17 @@ static u8 get_link_status(const u8 link_status[DP_LINK_STATUS_SIZE], int r)
*/
static int dp_link_process_link_status_update(struct dp_link_private *link)
{
- if (!(get_link_status(link->link_status,
- DP_LANE_ALIGN_STATUS_UPDATED) &
- DP_LINK_STATUS_UPDATED) ||
- (drm_dp_clock_recovery_ok(link->link_status,
- link->dp_link.link_params.num_lanes) &&
- drm_dp_channel_eq_ok(link->link_status,
- link->dp_link.link_params.num_lanes)))
- return -EINVAL;
+ bool channel_eq_done = drm_dp_channel_eq_ok(link->link_status,
+ link->dp_link.link_params.num_lanes);
+
+ bool clock_recovery_done = drm_dp_clock_recovery_ok(link->link_status,
+ link->dp_link.link_params.num_lanes);
DRM_DEBUG_DP("channel_eq_done = %d, clock_recovery_done = %d\n",
- drm_dp_clock_recovery_ok(link->link_status,
- link->dp_link.link_params.num_lanes),
- drm_dp_clock_recovery_ok(link->link_status,
- link->dp_link.link_params.num_lanes));
+ channel_eq_done, clock_recovery_done);
+
+ if (channel_eq_done && clock_recovery_done)
+ return -EINVAL;
return 0;
}
base-commit: 0855cb4b31953b8c539e57b970da8146bcd4405a
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] drm/msm/dp: skip checking LINK_STATUS_UPDATED bit
2020-10-20 16:59 [PATCH] drm/msm/dp: skip checking LINK_STATUS_UPDATED bit Kuogee Hsieh
@ 2020-10-20 22:15 ` Stephen Boyd
2020-10-30 22:06 ` khsieh
0 siblings, 1 reply; 3+ messages in thread
From: Stephen Boyd @ 2020-10-20 22:15 UTC (permalink / raw)
To: Kuogee Hsieh, robdclark, sean
Cc: tanmay, abhinavk, aravindh, khsieh, airlied, daniel,
linux-arm-msm, dri-devel, freedreno, linux-kernel
Quoting Kuogee Hsieh (2020-10-20 09:59:59)
> No need to check LINK_STATuS_UPDATED bit before
LINK_STATUS_UPDATED?
> return 6 bytes of link status during link training.
Why?
> This patch also fix phy compliance test link rate
> conversion error.
How?
>
> Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
> ---
Any Fixes: tag?
> drivers/gpu/drm/msm/dp/dp_ctrl.c | 20 ++++++--------------
> drivers/gpu/drm/msm/dp/dp_link.c | 24 +++++++++++-------------
> 2 files changed, 17 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> index 6bdaec778c4c..76e891c91c6e 100644
> --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
> +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
> @@ -1061,23 +1061,15 @@ static bool dp_ctrl_train_pattern_set(struct dp_ctrl_private *ctrl,
> static int dp_ctrl_read_link_status(struct dp_ctrl_private *ctrl,
> u8 *link_status)
> {
> - int len = 0;
> - u32 const offset = DP_LANE_ALIGN_STATUS_UPDATED - DP_LANE0_1_STATUS;
> - u32 link_status_read_max_retries = 100;
> -
> - while (--link_status_read_max_retries) {
> - len = drm_dp_dpcd_read_link_status(ctrl->aux,
> - link_status);
> - if (len != DP_LINK_STATUS_SIZE) {
> - DRM_ERROR("DP link status read failed, err: %d\n", len);
> - return len;
> - }
> + int ret = 0, len;
>
> - if (!(link_status[offset] & DP_LINK_STATUS_UPDATED))
> - return 0;
> + len = drm_dp_dpcd_read_link_status(ctrl->aux, link_status);
> + if (len != DP_LINK_STATUS_SIZE) {
> + DRM_ERROR("DP link status read failed, err: %d\n", len);
> + ret = len;
Could this be positive if the len is greater than 0 but not
DP_LINK_STATUS_SIZE? Maybe the check should be len < 0? We certainly
don't want to return some smaller size from this function, right?
> }
>
> - return -ETIMEDOUT;
> + return ret;
> }
>
> static int dp_ctrl_link_train_1(struct dp_ctrl_private *ctrl,
> diff --git a/drivers/gpu/drm/msm/dp/dp_link.c b/drivers/gpu/drm/msm/dp/dp_link.c
> index c811da515fb3..58d65daae3b3 100644
> --- a/drivers/gpu/drm/msm/dp/dp_link.c
> +++ b/drivers/gpu/drm/msm/dp/dp_link.c
> @@ -773,7 +773,8 @@ static int dp_link_process_link_training_request(struct dp_link_private *link)
> link->request.test_lane_count);
>
> link->dp_link.link_params.num_lanes = link->request.test_lane_count;
> - link->dp_link.link_params.rate = link->request.test_link_rate;
> + link->dp_link.link_params.rate =
> + drm_dp_bw_code_to_link_rate(link->request.test_link_rate);
Why are we storing bw_code in test_link_rate? This looks very confusing.
>
> return 0;
> }
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] drm/msm/dp: skip checking LINK_STATUS_UPDATED bit
2020-10-20 22:15 ` Stephen Boyd
@ 2020-10-30 22:06 ` khsieh
0 siblings, 0 replies; 3+ messages in thread
From: khsieh @ 2020-10-30 22:06 UTC (permalink / raw)
To: Stephen Boyd
Cc: robdclark, sean, tanmay, abhinavk, aravindh, airlied, daniel,
linux-arm-msm, dri-devel, freedreno, linux-kernel
On 2020-10-20 15:15, Stephen Boyd wrote:
> Quoting Kuogee Hsieh (2020-10-20 09:59:59)
>> No need to check LINK_STATuS_UPDATED bit before
>
> LINK_STATUS_UPDATED?
>
>> return 6 bytes of link status during link training.
>
> Why?
>
>> This patch also fix phy compliance test link rate
>> conversion error.
>
> How?
>
>>
>> Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
>> ---
>
> Any Fixes: tag?
>
>> drivers/gpu/drm/msm/dp/dp_ctrl.c | 20 ++++++--------------
>> drivers/gpu/drm/msm/dp/dp_link.c | 24 +++++++++++-------------
>> 2 files changed, 17 insertions(+), 27 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> b/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> index 6bdaec778c4c..76e891c91c6e 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> @@ -1061,23 +1061,15 @@ static bool dp_ctrl_train_pattern_set(struct
>> dp_ctrl_private *ctrl,
>> static int dp_ctrl_read_link_status(struct dp_ctrl_private *ctrl,
>> u8 *link_status)
>> {
>> - int len = 0;
>> - u32 const offset = DP_LANE_ALIGN_STATUS_UPDATED -
>> DP_LANE0_1_STATUS;
>> - u32 link_status_read_max_retries = 100;
>> -
>> - while (--link_status_read_max_retries) {
>> - len = drm_dp_dpcd_read_link_status(ctrl->aux,
>> - link_status);
>> - if (len != DP_LINK_STATUS_SIZE) {
>> - DRM_ERROR("DP link status read failed, err:
>> %d\n", len);
>> - return len;
>> - }
>> + int ret = 0, len;
>>
>> - if (!(link_status[offset] & DP_LINK_STATUS_UPDATED))
>> - return 0;
>> + len = drm_dp_dpcd_read_link_status(ctrl->aux, link_status);
>> + if (len != DP_LINK_STATUS_SIZE) {
>> + DRM_ERROR("DP link status read failed, err: %d\n",
>> len);
>> + ret = len;
>
> Could this be positive if the len is greater than 0 but not
> DP_LINK_STATUS_SIZE? Maybe the check should be len < 0? We certainly
> don't want to return some smaller size from this function, right?
>
no, it should be exactly the byte number requested to read.
otherwise, it should be failed and will re read at next run.
>> }
>>
>> - return -ETIMEDOUT;
>> + return ret;
>> }
>>
>> static int dp_ctrl_link_train_1(struct dp_ctrl_private *ctrl,
>> diff --git a/drivers/gpu/drm/msm/dp/dp_link.c
>> b/drivers/gpu/drm/msm/dp/dp_link.c
>> index c811da515fb3..58d65daae3b3 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_link.c
>> +++ b/drivers/gpu/drm/msm/dp/dp_link.c
>> @@ -773,7 +773,8 @@ static int
>> dp_link_process_link_training_request(struct dp_link_private *link)
>> link->request.test_lane_count);
>>
>> link->dp_link.link_params.num_lanes =
>> link->request.test_lane_count;
>> - link->dp_link.link_params.rate = link->request.test_link_rate;
>> + link->dp_link.link_params.rate =
>> +
>> drm_dp_bw_code_to_link_rate(link->request.test_link_rate);
>
> Why are we storing bw_code in test_link_rate? This looks very
> confusing.
Test_link_rate contains link rate from dpcd read. it need to be convert
to real
rate by timing 2.7Mb before start phy compliance test.
>
>>
>> return 0;
>> }
^ permalink raw reply [flat|nested] 3+ messages in thread
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2020-10-20 16:59 [PATCH] drm/msm/dp: skip checking LINK_STATUS_UPDATED bit Kuogee Hsieh
2020-10-20 22:15 ` Stephen Boyd
2020-10-30 22:06 ` khsieh
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