On 7/22/2025 11:26 AM, Suraj Kandpal wrote:
We need override certain link rates in favour of the next available
higher link rate. The Link rates that need to be overridden are
indicated by a mask in VBT. To make sure these modes are skipped we
don't add them in them in the sink rates array.
Signed-off-by: Suraj Kandpal <suraj.kand...@intel.com>
---
drivers/gpu/drm/i915/display/intel_bios.c | 56 +++++++++++++++++++++++
drivers/gpu/drm/i915/display/intel_bios.h | 2 +
drivers/gpu/drm/i915/display/intel_dp.c | 11 +++--
3 files changed, 66 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_bios.c
b/drivers/gpu/drm/i915/display/intel_bios.c
index 8337ebe0f2c8..e68f71c0575a 100644
--- a/drivers/gpu/drm/i915/display/intel_bios.c
+++ b/drivers/gpu/drm/i915/display/intel_bios.c
@@ -2480,6 +2480,53 @@ static int parse_bdb_216_dp_max_link_rate(const int
vbt_max_link_rate)
}
}
+static bool parse_bdb_263_edp_data_override(const u32 edp_data_override_mask, int rate)
+{
+ u32 val;
+
+ switch (rate) {
+ default:
+ case 2000000:
+ val = BDB_263_VBT_EDP_LINK_RATE_20;
+ break;
+ case 1350000:
+ val = BDB_263_VBT_EDP_LINK_RATE_13_5;
+ break;
+ case 1000000:
+ val = BDB_263_VBT_EDP_LINK_RATE_10;
+ break;
+ case 810000:
+ val = BDB_263_VBT_EDP_LINK_RATE_8_1;
+ break;
+ case 675000:
+ val = BDB_263_VBT_EDP_LINK_RATE_6_75;
+ break;
+ case 540000:
+ val = BDB_263_VBT_EDP_LINK_RATE_5_4;
+ break;
+ case 432000:
+ val = BDB_263_VBT_EDP_LINK_RATE_4_32;
+ break;
+ case 324000:
+ val = BDB_263_VBT_EDP_LINK_RATE_3_24;
+ break;
+ case 270000:
+ val = BDB_263_VBT_EDP_LINK_RATE_2_7;
+ break;
+ case 243000:
+ val = BDB_263_VBT_EDP_LINK_RATE_2_43;
+ break;
+ case 216000:
+ val = BDB_263_VBT_EDP_LINK_RATE_2_16;
+ break;
+ case 162000:
+ val = BDB_263_VBT_EDP_LINK_RATE_1_62;
+ break;
+ }
+
+ return edp_data_override_mask & val;
+}
+
int intel_bios_dp_max_link_rate(const struct intel_bios_encoder_data *devdata)
{
if (!devdata || devdata->display->vbt.version < 216)
@@ -2499,6 +2546,15 @@ int intel_bios_dp_max_lane_count(const struct
intel_bios_encoder_data *devdata)
return devdata->child.dp_max_lane_count + 1;
}
+bool
+intel_bios_edp_data_override(const struct intel_bios_encoder_data *devdata,
int rate)
+{
+ if (!devdata || devdata->display->vbt.version < 263)
+ return false;
+
+ return
parse_bdb_263_edp_data_override(devdata->child.edp_data_override, rate);
+}
+
I think this should be a separate patch or perhaps part of previous
patch where we define the bits.
static void sanitize_device_type(struct intel_bios_encoder_data *devdata,
enum port port)
{
diff --git a/drivers/gpu/drm/i915/display/intel_bios.h
b/drivers/gpu/drm/i915/display/intel_bios.h
index 6cd7a011b8c4..b554fff96082 100644
--- a/drivers/gpu/drm/i915/display/intel_bios.h
+++ b/drivers/gpu/drm/i915/display/intel_bios.h
@@ -274,5 +274,7 @@ void intel_bios_for_each_encoder(struct intel_display
*display,
const struct
intel_bios_encoder_data *devdata));
void intel_bios_debugfs_register(struct intel_display *display);
+bool
+intel_bios_edp_data_override(const struct intel_bios_encoder_data *devdata,
int rate);
#endif /* _INTEL_BIOS_H_ */
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c
b/drivers/gpu/drm/i915/display/intel_dp.c
index 6d4e0fa0c054..0a227822b46a 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -4275,12 +4275,13 @@ static void
intel_edp_set_sink_rates(struct intel_dp *intel_dp)
{
struct intel_display *display = to_intel_display(intel_dp);
+ struct intel_encoder *encoder = &dp_to_dig_port(intel_dp)->base;
intel_dp->num_sink_rates = 0;
if (intel_dp->edp_dpcd[0] >= DP_EDP_14) {
__le16 sink_rates[DP_MAX_SUPPORTED_RATES];
- int i;
+ int i, j = 0;
lets use count /count_rates here? i, j mostly are used for loop index.
This will make it clear that purpose is counting, and not iterating.
drm_dp_dpcd_read(&intel_dp->aux, DP_SUPPORTED_LINK_RATES,
sink_rates, sizeof(sink_rates));
@@ -4308,9 +4309,13 @@ intel_edp_set_sink_rates(struct intel_dp *intel_dp)
intel_has_quirk(display, QUIRK_EDP_LIMIT_RATE_HBR2))
break;
- intel_dp->sink_rates[i] = rate;
+ if (intel_bios_edp_data_override(encoder->devdata,
rate))
+ continue;
+
+ intel_dp->sink_rates[j] = rate;
+ j++;
Then this can simply be intel_dp->sink_rate[count++] = rate;
}
- intel_dp->num_sink_rates = i;
+ intel_dp->num_sink_rates = j;
And intel_dp->num_sink_rates= count;
}
For eDP < 1.4 that do not have SUPPORTED_LINK_RATES and use
MAX_LINK_RATE , for them intel_dp_set_sink_rates() sets the
intel_dp->sink_rates.
So need to have the override logic there also. Or perhaps we can do the
check for override at the end after sink_rates are already sent.
Regards,
Ankit
/*
