The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 8bf073ca9235fe38d7b74a0b4e779cfa7cc70fc9 Mon Sep 17 00:00:00 2001
From: Bas Nieuwenhuizen <bas(a)basnieuwenhuizen.nl>
Date: Wed, 5 May 2021 03:27:49 +0200
Subject: [PATCH] drm/amdgpu: Init GFX10_ADDR_CONFIG for VCN v3 in DPG mode.
Otherwise tiling modes that require the values form this field
(In particular _*_X) would be corrupted upon video decode.
Copied from the VCN v2 code.
Fixes: 99541f392b4d ("drm/amdgpu: add mc resume DPG mode for VCN3.0")
Reviewed-and-Tested by: Leo Liu <leo.liu(a)amd.com>
Signed-off-by: Bas Nieuwenhuizen <bas(a)basnieuwenhuizen.nl>
Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com>
Cc: stable(a)vger.kernel.org
diff --git a/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c b/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c
index 3f15bf34123a..cf165ab5dd26 100644
--- a/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/vcn_v3_0.c
@@ -589,6 +589,10 @@ static void vcn_v3_0_mc_resume_dpg_mode(struct amdgpu_device *adev, int inst_idx
WREG32_SOC15_DPG_MODE(inst_idx, SOC15_DPG_MODE_OFFSET(
VCN, inst_idx, mmUVD_VCPU_NONCACHE_SIZE0),
AMDGPU_GPU_PAGE_ALIGN(sizeof(struct amdgpu_fw_shared)), 0, indirect);
+
+ /* VCN global tiling registers */
+ WREG32_SOC15_DPG_MODE(0, SOC15_DPG_MODE_OFFSET(
+ UVD, 0, mmUVD_GFX10_ADDR_CONFIG), adev->gfx.config.gb_addr_config, 0, indirect);
}
static void vcn_v3_0_disable_static_power_gating(struct amdgpu_device *adev, int inst)
The patch below does not apply to the 5.11-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 264613b406eb0d74cd9ca582c717c5e2c5a975ea Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak(a)intel.com>
Date: Wed, 17 Mar 2021 21:01:49 +0200
Subject: [PATCH] drm/i915: Disable LTTPR support when the DPCD rev < 1.4
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
By the specification the 0xF0000-0xF02FF range is only valid when the
DPCD revision is 1.4 or higher. Disable LTTPR support if this isn't so.
Trying to detect LTTPRs returned corrupted values for the above DPCD
range at least on a Skylake host with an LG 43UD79-B monitor with a DPCD
revision 1.2 connected.
v2: Add the actual version check.
v3: Fix s/DRPX/DPRX/ typo.
Fixes: 7b2a4ab8b0ef ("drm/i915: Switch to LTTPR transparent mode link training")
Cc: <stable(a)vger.kernel.org> # v5.11
Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Signed-off-by: Imre Deak <imre.deak(a)intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210317190149.4032966-1-imre…
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index d46cd205241c..2c98335c260c 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -3709,9 +3709,7 @@ intel_dp_get_dpcd(struct intel_dp *intel_dp)
{
int ret;
- intel_dp_lttpr_init(intel_dp);
-
- if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd))
+ if (intel_dp_init_lttpr_and_dprx_caps(intel_dp) < 0)
return false;
/*
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index c0e25c75c105..f14ac2694183 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -35,6 +35,11 @@ intel_dp_dump_link_status(struct drm_device *drm,
link_status[3], link_status[4], link_status[5]);
}
+static void intel_dp_reset_lttpr_common_caps(struct intel_dp *intel_dp)
+{
+ memset(&intel_dp->lttpr_common_caps, 0, sizeof(intel_dp->lttpr_common_caps));
+}
+
static void intel_dp_reset_lttpr_count(struct intel_dp *intel_dp)
{
intel_dp->lttpr_common_caps[DP_PHY_REPEATER_CNT -
@@ -96,8 +101,7 @@ static bool intel_dp_read_lttpr_common_caps(struct intel_dp *intel_dp)
if (drm_dp_read_lttpr_common_caps(&intel_dp->aux,
intel_dp->lttpr_common_caps) < 0) {
- memset(intel_dp->lttpr_common_caps, 0,
- sizeof(intel_dp->lttpr_common_caps));
+ intel_dp_reset_lttpr_common_caps(intel_dp);
return false;
}
@@ -119,30 +123,49 @@ intel_dp_set_lttpr_transparent_mode(struct intel_dp *intel_dp, bool enable)
}
/**
- * intel_dp_lttpr_init - detect LTTPRs and init the LTTPR link training mode
+ * intel_dp_init_lttpr_and_dprx_caps - detect LTTPR and DPRX caps, init the LTTPR link training mode
* @intel_dp: Intel DP struct
*
- * Read the LTTPR common capabilities, switch to non-transparent link training
- * mode if any is detected and read the PHY capabilities for all detected
- * LTTPRs. In case of an LTTPR detection error or if the number of
+ * Read the LTTPR common and DPRX capabilities and switch to non-transparent
+ * link training mode if any is detected and read the PHY capabilities for all
+ * detected LTTPRs. In case of an LTTPR detection error or if the number of
* LTTPRs is more than is supported (8), fall back to the no-LTTPR,
* transparent mode link training mode.
*
* Returns:
- * >0 if LTTPRs were detected and the non-transparent LT mode was set
+ * >0 if LTTPRs were detected and the non-transparent LT mode was set. The
+ * DPRX capabilities are read out.
* 0 if no LTTPRs or more than 8 LTTPRs were detected or in case of a
- * detection failure and the transparent LT mode was set
+ * detection failure and the transparent LT mode was set. The DPRX
+ * capabilities are read out.
+ * <0 Reading out the DPRX capabilities failed.
*/
-int intel_dp_lttpr_init(struct intel_dp *intel_dp)
+int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp)
{
int lttpr_count;
bool ret;
int i;
ret = intel_dp_read_lttpr_common_caps(intel_dp);
+
+ /* The DPTX shall read the DPRX caps after LTTPR detection. */
+ if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd)) {
+ intel_dp_reset_lttpr_common_caps(intel_dp);
+ return -EIO;
+ }
+
if (!ret)
return 0;
+ /*
+ * The 0xF0000-0xF02FF range is only valid if the DPCD revision is
+ * at least 1.4.
+ */
+ if (intel_dp->dpcd[DP_DPCD_REV] < 0x14) {
+ intel_dp_reset_lttpr_common_caps(intel_dp);
+ return 0;
+ }
+
lttpr_count = drm_dp_lttpr_count(intel_dp->lttpr_common_caps);
/*
* Prevent setting LTTPR transparent mode explicitly if no LTTPRs are
@@ -182,7 +205,7 @@ int intel_dp_lttpr_init(struct intel_dp *intel_dp)
return lttpr_count;
}
-EXPORT_SYMBOL(intel_dp_lttpr_init);
+EXPORT_SYMBOL(intel_dp_init_lttpr_and_dprx_caps);
static u8 dp_voltage_max(u8 preemph)
{
@@ -817,7 +840,10 @@ void intel_dp_start_link_train(struct intel_dp *intel_dp,
* TODO: Reiniting LTTPRs here won't be needed once proper connector
* HW state readout is added.
*/
- int lttpr_count = intel_dp_lttpr_init(intel_dp);
+ int lttpr_count = intel_dp_init_lttpr_and_dprx_caps(intel_dp);
+
+ if (lttpr_count < 0)
+ return;
if (!intel_dp_link_train_all_phys(intel_dp, crtc_state, lttpr_count))
intel_dp_schedule_fallback_link_training(intel_dp, crtc_state);
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.h b/drivers/gpu/drm/i915/display/intel_dp_link_training.h
index 6a1f76bd8c75..9cb7c28027f0 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.h
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.h
@@ -11,7 +11,7 @@
struct intel_crtc_state;
struct intel_dp;
-int intel_dp_lttpr_init(struct intel_dp *intel_dp);
+int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp);
void intel_dp_get_adjust_train(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state,
The patch below does not apply to the 5.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 264613b406eb0d74cd9ca582c717c5e2c5a975ea Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak(a)intel.com>
Date: Wed, 17 Mar 2021 21:01:49 +0200
Subject: [PATCH] drm/i915: Disable LTTPR support when the DPCD rev < 1.4
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
By the specification the 0xF0000-0xF02FF range is only valid when the
DPCD revision is 1.4 or higher. Disable LTTPR support if this isn't so.
Trying to detect LTTPRs returned corrupted values for the above DPCD
range at least on a Skylake host with an LG 43UD79-B monitor with a DPCD
revision 1.2 connected.
v2: Add the actual version check.
v3: Fix s/DRPX/DPRX/ typo.
Fixes: 7b2a4ab8b0ef ("drm/i915: Switch to LTTPR transparent mode link training")
Cc: <stable(a)vger.kernel.org> # v5.11
Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Signed-off-by: Imre Deak <imre.deak(a)intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210317190149.4032966-1-imre…
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index d46cd205241c..2c98335c260c 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -3709,9 +3709,7 @@ intel_dp_get_dpcd(struct intel_dp *intel_dp)
{
int ret;
- intel_dp_lttpr_init(intel_dp);
-
- if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd))
+ if (intel_dp_init_lttpr_and_dprx_caps(intel_dp) < 0)
return false;
/*
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index c0e25c75c105..f14ac2694183 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -35,6 +35,11 @@ intel_dp_dump_link_status(struct drm_device *drm,
link_status[3], link_status[4], link_status[5]);
}
+static void intel_dp_reset_lttpr_common_caps(struct intel_dp *intel_dp)
+{
+ memset(&intel_dp->lttpr_common_caps, 0, sizeof(intel_dp->lttpr_common_caps));
+}
+
static void intel_dp_reset_lttpr_count(struct intel_dp *intel_dp)
{
intel_dp->lttpr_common_caps[DP_PHY_REPEATER_CNT -
@@ -96,8 +101,7 @@ static bool intel_dp_read_lttpr_common_caps(struct intel_dp *intel_dp)
if (drm_dp_read_lttpr_common_caps(&intel_dp->aux,
intel_dp->lttpr_common_caps) < 0) {
- memset(intel_dp->lttpr_common_caps, 0,
- sizeof(intel_dp->lttpr_common_caps));
+ intel_dp_reset_lttpr_common_caps(intel_dp);
return false;
}
@@ -119,30 +123,49 @@ intel_dp_set_lttpr_transparent_mode(struct intel_dp *intel_dp, bool enable)
}
/**
- * intel_dp_lttpr_init - detect LTTPRs and init the LTTPR link training mode
+ * intel_dp_init_lttpr_and_dprx_caps - detect LTTPR and DPRX caps, init the LTTPR link training mode
* @intel_dp: Intel DP struct
*
- * Read the LTTPR common capabilities, switch to non-transparent link training
- * mode if any is detected and read the PHY capabilities for all detected
- * LTTPRs. In case of an LTTPR detection error or if the number of
+ * Read the LTTPR common and DPRX capabilities and switch to non-transparent
+ * link training mode if any is detected and read the PHY capabilities for all
+ * detected LTTPRs. In case of an LTTPR detection error or if the number of
* LTTPRs is more than is supported (8), fall back to the no-LTTPR,
* transparent mode link training mode.
*
* Returns:
- * >0 if LTTPRs were detected and the non-transparent LT mode was set
+ * >0 if LTTPRs were detected and the non-transparent LT mode was set. The
+ * DPRX capabilities are read out.
* 0 if no LTTPRs or more than 8 LTTPRs were detected or in case of a
- * detection failure and the transparent LT mode was set
+ * detection failure and the transparent LT mode was set. The DPRX
+ * capabilities are read out.
+ * <0 Reading out the DPRX capabilities failed.
*/
-int intel_dp_lttpr_init(struct intel_dp *intel_dp)
+int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp)
{
int lttpr_count;
bool ret;
int i;
ret = intel_dp_read_lttpr_common_caps(intel_dp);
+
+ /* The DPTX shall read the DPRX caps after LTTPR detection. */
+ if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd)) {
+ intel_dp_reset_lttpr_common_caps(intel_dp);
+ return -EIO;
+ }
+
if (!ret)
return 0;
+ /*
+ * The 0xF0000-0xF02FF range is only valid if the DPCD revision is
+ * at least 1.4.
+ */
+ if (intel_dp->dpcd[DP_DPCD_REV] < 0x14) {
+ intel_dp_reset_lttpr_common_caps(intel_dp);
+ return 0;
+ }
+
lttpr_count = drm_dp_lttpr_count(intel_dp->lttpr_common_caps);
/*
* Prevent setting LTTPR transparent mode explicitly if no LTTPRs are
@@ -182,7 +205,7 @@ int intel_dp_lttpr_init(struct intel_dp *intel_dp)
return lttpr_count;
}
-EXPORT_SYMBOL(intel_dp_lttpr_init);
+EXPORT_SYMBOL(intel_dp_init_lttpr_and_dprx_caps);
static u8 dp_voltage_max(u8 preemph)
{
@@ -817,7 +840,10 @@ void intel_dp_start_link_train(struct intel_dp *intel_dp,
* TODO: Reiniting LTTPRs here won't be needed once proper connector
* HW state readout is added.
*/
- int lttpr_count = intel_dp_lttpr_init(intel_dp);
+ int lttpr_count = intel_dp_init_lttpr_and_dprx_caps(intel_dp);
+
+ if (lttpr_count < 0)
+ return;
if (!intel_dp_link_train_all_phys(intel_dp, crtc_state, lttpr_count))
intel_dp_schedule_fallback_link_training(intel_dp, crtc_state);
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.h b/drivers/gpu/drm/i915/display/intel_dp_link_training.h
index 6a1f76bd8c75..9cb7c28027f0 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.h
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.h
@@ -11,7 +11,7 @@
struct intel_crtc_state;
struct intel_dp;
-int intel_dp_lttpr_init(struct intel_dp *intel_dp);
+int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp);
void intel_dp_get_adjust_train(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state,
The patch below does not apply to the 5.11-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 1663ad4936e0679443a315fe342f99636a2420dd Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak(a)intel.com>
Date: Wed, 17 Mar 2021 20:49:01 +0200
Subject: [PATCH] drm/i915: Disable LTTPR support when the LTTPR rev < 1.4
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
By the specification the 0xF0000 - 0xF02FF range is only valid if the
LTTPR revision at 0xF0000 is at least 1.4. Disable the LTTPR support
otherwise.
Fixes: 7b2a4ab8b0ef ("drm/i915: Switch to LTTPR transparent mode link training")
Cc: <stable(a)vger.kernel.org> # v5.11
Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Signed-off-by: Imre Deak <imre.deak(a)intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210317184901.4029798-4-imre…
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index f14ac2694183..7d4e6f3e7e93 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -100,17 +100,23 @@ static bool intel_dp_read_lttpr_common_caps(struct intel_dp *intel_dp)
return false;
if (drm_dp_read_lttpr_common_caps(&intel_dp->aux,
- intel_dp->lttpr_common_caps) < 0) {
- intel_dp_reset_lttpr_common_caps(intel_dp);
- return false;
- }
+ intel_dp->lttpr_common_caps) < 0)
+ goto reset_caps;
drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
"LTTPR common capabilities: %*ph\n",
(int)sizeof(intel_dp->lttpr_common_caps),
intel_dp->lttpr_common_caps);
+ /* The minimum value of LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV is 1.4 */
+ if (intel_dp->lttpr_common_caps[0] < 0x14)
+ goto reset_caps;
+
return true;
+
+reset_caps:
+ intel_dp_reset_lttpr_common_caps(intel_dp);
+ return false;
}
static bool
The patch below does not apply to the 5.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 1663ad4936e0679443a315fe342f99636a2420dd Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak(a)intel.com>
Date: Wed, 17 Mar 2021 20:49:01 +0200
Subject: [PATCH] drm/i915: Disable LTTPR support when the LTTPR rev < 1.4
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
By the specification the 0xF0000 - 0xF02FF range is only valid if the
LTTPR revision at 0xF0000 is at least 1.4. Disable the LTTPR support
otherwise.
Fixes: 7b2a4ab8b0ef ("drm/i915: Switch to LTTPR transparent mode link training")
Cc: <stable(a)vger.kernel.org> # v5.11
Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Signed-off-by: Imre Deak <imre.deak(a)intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210317184901.4029798-4-imre…
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index f14ac2694183..7d4e6f3e7e93 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -100,17 +100,23 @@ static bool intel_dp_read_lttpr_common_caps(struct intel_dp *intel_dp)
return false;
if (drm_dp_read_lttpr_common_caps(&intel_dp->aux,
- intel_dp->lttpr_common_caps) < 0) {
- intel_dp_reset_lttpr_common_caps(intel_dp);
- return false;
- }
+ intel_dp->lttpr_common_caps) < 0)
+ goto reset_caps;
drm_dbg_kms(&dp_to_i915(intel_dp)->drm,
"LTTPR common capabilities: %*ph\n",
(int)sizeof(intel_dp->lttpr_common_caps),
intel_dp->lttpr_common_caps);
+ /* The minimum value of LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV is 1.4 */
+ if (intel_dp->lttpr_common_caps[0] < 0x14)
+ goto reset_caps;
+
return true;
+
+reset_caps:
+ intel_dp_reset_lttpr_common_caps(intel_dp);
+ return false;
}
static bool
The patch below does not apply to the 5.11-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 984982f3ef7b240cd24c2feb2762d81d9d8da3c2 Mon Sep 17 00:00:00 2001
From: Imre Deak <imre.deak(a)intel.com>
Date: Wed, 17 Mar 2021 20:48:59 +0200
Subject: [PATCH] drm/i915/ilk-glk: Fix link training on links with LTTPRs
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
The spec requires to use at least 3.2ms for the AUX timeout period if
there are LT-tunable PHY Repeaters on the link (2.11.2). An upcoming
spec update makes this more specific, by requiring a 3.2ms minimum
timeout period for the LTTPR detection reading the 0xF0000-0xF0007
range (3.6.5.1).
Accordingly disable LTTPR detection until GLK, where the maximum timeout
we can set is only 1.6ms.
Link training in the non-transparent mode is known to fail at least on
some SKL systems with a WD19 dock on the link, which exposes an LTTPR
(see the References below). While this could have different reasons
besides the too short AUX timeout used, not detecting LTTPRs (and so not
using the non-transparent LT mode) fixes link training on these systems.
While at it add a code comment about the platform specific maximum
timeout values.
v2: Add a comment about the g4x maximum timeout as well. (Ville)
Reported-by: Takashi Iwai <tiwai(a)suse.de>
Reported-and-tested-by: Santiago Zarate <santiago.zarate(a)suse.com>
Reported-and-tested-by: Bodo Graumann <mail(a)bodograumann.de>
References: https://gitlab.freedesktop.org/drm/intel/-/issues/3166
Fixes: b30edfd8d0b4 ("drm/i915: Switch to LTTPR non-transparent mode link training")
Cc: <stable(a)vger.kernel.org> # v5.11
Cc: Takashi Iwai <tiwai(a)suse.de>
Cc: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Signed-off-by: Imre Deak <imre.deak(a)intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala(a)linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210317184901.4029798-2-imre…
diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux.c b/drivers/gpu/drm/i915/display/intel_dp_aux.c
index eaebf123310a..10fe17b7280d 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_aux.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_aux.c
@@ -133,6 +133,7 @@ static u32 g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
else
precharge = 5;
+ /* Max timeout value on G4x-BDW: 1.6ms */
if (IS_BROADWELL(dev_priv))
timeout = DP_AUX_CH_CTL_TIME_OUT_600us;
else
@@ -159,6 +160,12 @@ static u32 skl_get_aux_send_ctl(struct intel_dp *intel_dp,
enum phy phy = intel_port_to_phy(i915, dig_port->base.port);
u32 ret;
+ /*
+ * Max timeout values:
+ * SKL-GLK: 1.6ms
+ * CNL: 3.2ms
+ * ICL+: 4ms
+ */
ret = DP_AUX_CH_CTL_SEND_BUSY |
DP_AUX_CH_CTL_DONE |
DP_AUX_CH_CTL_INTERRUPT |
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index 19ba7c7cbaab..c0e25c75c105 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -82,6 +82,18 @@ static void intel_dp_read_lttpr_phy_caps(struct intel_dp *intel_dp,
static bool intel_dp_read_lttpr_common_caps(struct intel_dp *intel_dp)
{
+ struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+
+ if (intel_dp_is_edp(intel_dp))
+ return false;
+
+ /*
+ * Detecting LTTPRs must be avoided on platforms with an AUX timeout
+ * period < 3.2ms. (see DP Standard v2.0, 2.11.2, 3.6.6.1).
+ */
+ if (INTEL_GEN(i915) < 10)
+ return false;
+
if (drm_dp_read_lttpr_common_caps(&intel_dp->aux,
intel_dp->lttpr_common_caps) < 0) {
memset(intel_dp->lttpr_common_caps, 0,
@@ -127,9 +139,6 @@ int intel_dp_lttpr_init(struct intel_dp *intel_dp)
bool ret;
int i;
- if (intel_dp_is_edp(intel_dp))
- return 0;
-
ret = intel_dp_read_lttpr_common_caps(intel_dp);
if (!ret)
return 0;