drm/amd/display: Fix IGT ILR link training failure on Replay panel

[Why & How]
Fix the IGT ilr_link-training-configs test failure
by directly using the supported link rates from DPCD.

Reviewed-by: ChiaHsuan Chung <chiahsuan.chung@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
index 5fb573214f18befe0399b9f2fb4e644a625992c3..cfe35442dfcb2806759d6bf75cb27d5633be9a2c 100644 (file)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_debugfs.c
@@ -46,6 +46,7 @@
 #include "amdgpu_dm_psr.h"
 #endif
 
+#define MULTIPLIER_TO_LR 270000
 struct dmub_debugfs_trace_header {
        uint32_t entry_count;
        uint32_t reserved[3];
@@ -3507,6 +3508,10 @@ static ssize_t edp_ilr_write(struct file *f, const char __user *buf,
        uint8_t param_nums = 0;
        long param[2];
        bool valid_input = true;
+       uint8_t supported_link_rates[16] = {0};
+       uint32_t entry = 0;
+       uint32_t link_rate_in_khz = 0;
+       uint8_t dpcd_rev = 0;
 
        if (size == 0)
                return -EINVAL;
@@ -3551,6 +3556,20 @@ static ssize_t edp_ilr_write(struct file *f, const char __user *buf,
                return size;
        }
 
+       if (!dm_helpers_dp_read_dpcd(link->ctx, link, DP_SUPPORTED_LINK_RATES,
+               supported_link_rates, sizeof(supported_link_rates)))
+               return -EINVAL;
+
+       dpcd_rev = link->dpcd_caps.dpcd_rev.raw;
+       if (dpcd_rev < DP_DPCD_REV_13 ||
+               (supported_link_rates[entry + 1] == 0 && supported_link_rates[entry] == 0)) {
+               return size;
+       }
+
+       entry = param[1] * 2;
+       link_rate_in_khz = (supported_link_rates[entry + 1] * 0x100 +
+                                               supported_link_rates[entry]) * 200;
+
        /* save user force lane_count, link_rate to preferred settings
         * spread spectrum will not be changed
         */
@@ -3558,7 +3577,7 @@ static ssize_t edp_ilr_write(struct file *f, const char __user *buf,
        prefer_link_settings.lane_count = param[0];
        prefer_link_settings.use_link_rate_set = true;
        prefer_link_settings.link_rate_set = param[1];
-       prefer_link_settings.link_rate = link->dpcd_caps.edp_supported_link_rates[param[1]];
+       prefer_link_settings.link_rate = link_rate_in_khz / MULTIPLIER_TO_LR;
 
        mutex_lock(&adev->dm.dc_lock);
        dc_link_set_preferred_training_settings(dc, &prefer_link_settings,