[PATCH 1/2] drm/edid: populate monitor_range from DisplayID Dynamic Video Timing block

[PATCH 1/2] drm/edid: populate monitor_range from DisplayID Dynamic Video Timing block

[Adriano Vero]

Some eDP panels report their VRR limits only via a DisplayID v1r2
Dynamic Video Timing Range Limits block (tag 0x25), without setting
DRM_EDID_FEATURE_CONTINUOUS_FREQ. drm_get_monitor_range() returns
early for such panels, leaving monitor_range zeroed.

Add drm_get_monitor_range_displayid() and call it from
update_display_info() immediately after drm_get_monitor_range(). It
uses displayid_iter_edid_begin() to locate Dynamic Video Timing blocks
and extracts min/max refresh rates, including the 10-bit max_vfreq
encoding signalled by block->rev bits [2:0]. It is a no-op when
monitor_range is already populated by the classic EDID path.

All drivers reading display_info.monitor_range now receive correct VRR
limits from DisplayID-only panels without any raw EDID access.

Byte offsets verified against parse_edid_displayid_vrr() in amdgpu_dm.c.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Adriano Vero <litaliano00.contact@gmail.com>
---
 drivers/gpu/drm/drm_edid.c | 68 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 66 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index ff432ac6b..d2c360178 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -6504,6 +6504,71 @@ void get_monitor_range(const struct detailed_timing *timing, void *c)
 	}
 }
 
+/**
+ * drm_get_monitor_range_displayid - populate monitor_range from a
+ * DisplayID v1r2 Dynamic Video Timing Range Limits block (tag 0x25).
+ *
+ * Some eDP panels report their VRR limits only in a DisplayID block,
+ * without setting DRM_EDID_FEATURE_CONTINUOUS_FREQ. drm_get_monitor_range()
+ * returns early for such panels, leaving monitor_range zeroed. This
+ * function is called separately from update_display_info() as a fallback.
+ *
+ * Block payload layout (block->num_bytes == 9):
+ *   data[6]       min_vfreq in Hz
+ *   data[7]       max_vfreq low 8 bits
+ *   data[8][1:0]  max_vfreq high bits (when block->rev & 7 is nonzero)
+ *
+ * Byte offsets verified against parse_edid_displayid_vrr() in amdgpu_dm.c.
+ */
+static void
+drm_get_monitor_range_displayid(struct drm_connector *connector,
+				const struct drm_edid *drm_edid)
+{
+	struct drm_display_info *info = &connector->display_info;
+	const struct displayid_block *block;
+	struct displayid_iter iter;
+
+	/* Only run when the classic EDID path left these zeroed */
+	if (info->monitor_range.min_vfreq && info->monitor_range.max_vfreq)
+		return;
+
+	displayid_iter_edid_begin(drm_edid, &iter);
+	displayid_iter_for_each(block, &iter) {
+		const u8 *data;
+		u16 min_vfreq, max_vfreq;
+
+		if (block->tag != DATA_BLOCK_2_DYNAMIC_VIDEO_TIMING)
+			continue;
+
+		/* rev bits [7:1] must be zero; payload must be exactly 9 bytes */
+		if ((block->rev & 0xFE) != 0 || block->num_bytes != 9)
+			continue;
+
+		data = (const u8 *)(block + 1);
+
+		min_vfreq = data[6];
+
+		/* rev bits [2:0] nonzero: max_vfreq is 10-bit */
+		if (block->rev & 7)
+			max_vfreq = data[7] | ((u16)(data[8] & 3) << 8);
+		else
+			max_vfreq = data[7];
+
+		if (!min_vfreq || !max_vfreq)
+			continue;
+
+		info->monitor_range.min_vfreq = min_vfreq;
+		info->monitor_range.max_vfreq = max_vfreq;
+
+		drm_dbg_kms(connector->dev,
+			    "[CONNECTOR:%d:%s] DisplayID dynamic video timing range: %u-%u Hz\n",
+			    connector->base.id, connector->name,
+			    min_vfreq, max_vfreq);
+		break;
+	}
+	displayid_iter_end(&iter);
+}
+
 static void drm_get_monitor_range(struct drm_connector *connector,
 				  const struct drm_edid *drm_edid)
 {
@@ -6691,10 +6756,9 @@ static void update_display_info(struct drm_connector *connector,
 	info->height_mm = edid->height_cm * 10;
 
 	drm_get_monitor_range(connector, drm_edid);
-
+	drm_get_monitor_range_displayid(connector, drm_edid);
 	if (edid->revision < 3)
 		goto out;
-
 	if (!drm_edid_is_digital(drm_edid))
 		goto out;
 
-- 
2.47.3

[PATCH 2/2] drm/amd/display: remove manual DisplayID VRR parsing from freesync caps

[Adriano Vero]

parse_edid_displayid_vrr() walked raw DisplayID bytes via struct edid*
to find Dynamic Video Timing Range Limits blocks when monitor_range
was zeroed. This is a layering violation.

Now that drm_get_monitor_range_displayid() in the DRM core fills
monitor_range from DisplayID Dynamic Video Timing blocks via the
proper displayid_iter infrastructure, parse_edid_displayid_vrr() is
redundant. Remove it and its drm_edid_raw() call from the VRR path.

drm_edid_raw() remains for parse_amd_vsdb() and parse_hdmi_amd_vsdb()
which read AMD vendor-specific CEA data blocks; those are tracked
separately.

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Rodrigo.Siqueira@amd.com
Signed-off-by: Adriano Vero <litaliano00.contact@gmail.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 61 ++++---------------
 1 file changed, 11 insertions(+), 50 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 085cc98bd..c61d6e1fe 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -13110,49 +13110,6 @@ static bool parse_edid_cea(struct amdgpu_dm_connector *aconnector,
 	return ret;
 }
 
-static void parse_edid_displayid_vrr(struct drm_connector *connector,
-				     const struct edid *edid)
-{
-	u8 *edid_ext = NULL;
-	int i;
-	int j = 0;
-	u16 min_vfreq;
-	u16 max_vfreq;
-
-	if (!edid || !edid->extensions)
-		return;
-
-	/* Find DisplayID extension */
-	for (i = 0; i < edid->extensions; i++) {
-		edid_ext = (void *)(edid + (i + 1));
-		if (edid_ext[0] == DISPLAYID_EXT)
-			break;
-	}
-
-	if (i == edid->extensions)
-		return;
-
-	while (j < EDID_LENGTH) {
-		/* Get dynamic video timing range from DisplayID if available */
-		if (EDID_LENGTH - j > 13 && edid_ext[j] == 0x25	&&
-		    (edid_ext[j+1] & 0xFE) == 0 && (edid_ext[j+2] == 9)) {
-			min_vfreq = edid_ext[j+9];
-			if (edid_ext[j+1] & 7)
-				max_vfreq = edid_ext[j+10] + ((edid_ext[j+11] & 3) << 8);
-			else
-				max_vfreq = edid_ext[j+10];
-
-			if (max_vfreq && min_vfreq) {
-				connector->display_info.monitor_range.max_vfreq = max_vfreq;
-				connector->display_info.monitor_range.min_vfreq = min_vfreq;
-
-				return;
-			}
-		}
-		j++;
-	}
-}
-
 static int parse_amd_vsdb(struct amdgpu_dm_connector *aconnector,
 			  const struct edid *edid, struct amdgpu_hdmi_vsdb_info *vsdb_info)
 {
@@ -13288,13 +13245,17 @@ void amdgpu_dm_update_freesync_caps(struct drm_connector *connector,
 	if (!adev->dm.freesync_module || !dc_supports_vrr(sink->ctx->dce_version))
 		goto update;
 
-	edid = drm_edid_raw(drm_edid); // FIXME: Get rid of drm_edid_raw()
-
-	/* Some eDP panels only have the refresh rate range info in DisplayID */
-	if ((connector->display_info.monitor_range.min_vfreq == 0 ||
-	     connector->display_info.monitor_range.max_vfreq == 0))
-		parse_edid_displayid_vrr(connector, edid);
-
+	/**
+	 * monitor_range is now populated by the DRM core from both classic
+	 * EDID Monitor Range Limits descriptors and DisplayID Dynamic Video
+	 * Timing blocks (tag 0x25) via drm_get_monitor_range_displayid().
+	 * parse_edid_displayid_vrr() has been removed.
+	 *
+	 * drm_edid_raw() is retained only for parse_amd_vsdb() and
+	 * parse_hdmi_amd_vsdb() which read AMD vendor-specific CEA blocks.
+	 * Removing those raw accesses is tracked separately.
+	 */
+	edid = drm_edid_raw(drm_edid); /* TODO: amd/hdmi vsdb refactor */
 	if (edid && (sink->sink_signal == SIGNAL_TYPE_DISPLAY_PORT ||
 		     sink->sink_signal == SIGNAL_TYPE_EDP)) {
 		if (amdgpu_dm_connector->dc_link &&
-- 
2.47.3

Re: [PATCH 1/2] drm/edid: populate monitor_range from DisplayID Dynamic Video Timing block

[kernel test robot]

Hi Adriano,

kernel test robot noticed the following build warnings:

[auto build test WARNING on drm/drm-next]
[also build test WARNING on drm-i915/for-linux-next drm-i915/for-linux-next-fixes drm-tip/drm-tip linus/master v7.0-rc6 next-20260327]
[cannot apply to drm-misc/drm-misc-next daeinki-drm-exynos/exynos-drm-next]
[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/Adriano-Vero/drm-amd-display-remove-manual-DisplayID-VRR-parsing-from-freesync-caps/20260330-002329
base:   https://gitlab.freedesktop.org/drm/kernel.git drm-next
patch link:    https://lore.kernel.org/r/20260328132027.22383-1-litaliano00.contact%40gmail.com
patch subject: [PATCH 1/2] drm/edid: populate monitor_range from DisplayID Dynamic Video Timing block
config: alpha-randconfig-r073-20260330 (https://download.01.org/0day-ci/archive/20260330/202603301304.Vwu3Sqd7-lkp@intel.com/config)
compiler: alpha-linux-gcc (GCC) 14.3.0
smatch: v0.5.0-9004-gb810ac53
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260330/202603301304.Vwu3Sqd7-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202603301304.Vwu3Sqd7-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> Warning: drivers/gpu/drm/drm_edid.c:6525 function parameter 'connector' not described in 'drm_get_monitor_range_displayid'
>> Warning: drivers/gpu/drm/drm_edid.c:6525 function parameter 'drm_edid' not described in 'drm_get_monitor_range_displayid'
>> Warning: drivers/gpu/drm/drm_edid.c:6525 function parameter 'connector' not described in 'drm_get_monitor_range_displayid'
>> Warning: drivers/gpu/drm/drm_edid.c:6525 function parameter 'drm_edid' not described in 'drm_get_monitor_range_displayid'

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH 1/2] drm/edid: populate monitor_range from DisplayID Dynamic Video Timing block

[kernel test robot]

Hi Adriano,

kernel test robot noticed the following build warnings:

[auto build test WARNING on drm/drm-next]
[also build test WARNING on drm-i915/for-linux-next drm-i915/for-linux-next-fixes drm-tip/drm-tip linus/master v7.0-rc6 next-20260327]
[cannot apply to drm-misc/drm-misc-next daeinki-drm-exynos/exynos-drm-next]
[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/Adriano-Vero/drm-amd-display-remove-manual-DisplayID-VRR-parsing-from-freesync-caps/20260330-002329
base:   https://gitlab.freedesktop.org/drm/kernel.git drm-next
patch link:    https://lore.kernel.org/r/20260328132027.22383-1-litaliano00.contact%40gmail.com
patch subject: [PATCH 1/2] drm/edid: populate monitor_range from DisplayID Dynamic Video Timing block
config: x86_64-rhel-9.4 (https://download.01.org/0day-ci/archive/20260330/202603300847.vflE6oJO-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260330/202603300847.vflE6oJO-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202603300847.vflE6oJO-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> Warning: drivers/gpu/drm/drm_edid.c:6525 function parameter 'connector' not described in 'drm_get_monitor_range_displayid'
>> Warning: drivers/gpu/drm/drm_edid.c:6525 function parameter 'drm_edid' not described in 'drm_get_monitor_range_displayid'
>> Warning: drivers/gpu/drm/drm_edid.c:6525 function parameter 'connector' not described in 'drm_get_monitor_range_displayid'
>> Warning: drivers/gpu/drm/drm_edid.c:6525 function parameter 'drm_edid' not described in 'drm_get_monitor_range_displayid'

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Re: [PATCH 1/2] drm/edid: populate monitor_range from DisplayID Dynamic Video Timing block

[Jani Nikula]

On Sat, 28 Mar 2026, Adriano Vero <litaliano00.contact@gmail.com> wrote:
> Some eDP panels report their VRR limits only via a DisplayID v1r2
> Dynamic Video Timing Range Limits block (tag 0x25), without setting

That's a contradiction right there. DisplayID v1r2 does not have tag
0x25. DisplayID v2r0 does. All the DATA_BLOCK_2_* are only defined for
v2r0.

> DRM_EDID_FEATURE_CONTINUOUS_FREQ. drm_get_monitor_range() returns
> early for such panels, leaving monitor_range zeroed.
>
> Add drm_get_monitor_range_displayid() and call it from
> update_display_info() immediately after drm_get_monitor_range(). It
> uses displayid_iter_edid_begin() to locate Dynamic Video Timing blocks
> and extracts min/max refresh rates, including the 10-bit max_vfreq
> encoding signalled by block->rev bits [2:0]. It is a no-op when
> monitor_range is already populated by the classic EDID path.
>
> All drivers reading display_info.monitor_range now receive correct VRR
> limits from DisplayID-only panels without any raw EDID access.
>
> Byte offsets verified against parse_edid_displayid_vrr() in amdgpu_dm.c.
>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Cc: dri-devel@lists.freedesktop.org
> Signed-off-by: Adriano Vero <litaliano00.contact@gmail.com>
> ---
>  drivers/gpu/drm/drm_edid.c | 68 ++++++++++++++++++++++++++++++++++++--
>  1 file changed, 66 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> index ff432ac6b..d2c360178 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -6504,6 +6504,71 @@ void get_monitor_range(const struct detailed_timing *timing, void *c)
>  	}
>  }
>  
> +/**
> + * drm_get_monitor_range_displayid - populate monitor_range from a

Please no kernel-doc for static functions here.

> + * DisplayID v1r2 Dynamic Video Timing Range Limits block (tag 0x25).
> + *
> + * Some eDP panels report their VRR limits only in a DisplayID block,
> + * without setting DRM_EDID_FEATURE_CONTINUOUS_FREQ. drm_get_monitor_range()
> + * returns early for such panels, leaving monitor_range zeroed. This
> + * function is called separately from update_display_info() as a fallback.

Useless info. Please don't repeat what's obvious from the code.

> + *
> + * Block payload layout (block->num_bytes == 9):
> + *   data[6]       min_vfreq in Hz
> + *   data[7]       max_vfreq low 8 bits
> + *   data[8][1:0]  max_vfreq high bits (when block->rev & 7 is nonzero)
> + *
> + * Byte offsets verified against parse_edid_displayid_vrr() in amdgpu_dm.c.

Useless info.

> + */
> +static void
> +drm_get_monitor_range_displayid(struct drm_connector *connector,
> +				const struct drm_edid *drm_edid)
> +{
> +	struct drm_display_info *info = &connector->display_info;
> +	const struct displayid_block *block;
> +	struct displayid_iter iter;
> +
> +	/* Only run when the classic EDID path left these zeroed */
> +	if (info->monitor_range.min_vfreq && info->monitor_range.max_vfreq)
> +		return;
> +
> +	displayid_iter_edid_begin(drm_edid, &iter);
> +	displayid_iter_for_each(block, &iter) {
> +		const u8 *data;
> +		u16 min_vfreq, max_vfreq;
> +
> +		if (block->tag != DATA_BLOCK_2_DYNAMIC_VIDEO_TIMING)
> +			continue;

It would be pedantically correct to also check the
displayid_version(). See displayid_is_tiled_block() for an example.

> +
> +		/* rev bits [7:1] must be zero; payload must be exactly 9 bytes */

I can see all of that from the code. The comment doesn't add anything
helpful. If it explained why, it would go a long way.

> +		if ((block->rev & 0xFE) != 0 || block->num_bytes != 9)
> +			continue;
> +
> +		data = (const u8 *)(block + 1);
> +
> +		min_vfreq = data[6];
> +
> +		/* rev bits [2:0] nonzero: max_vfreq is 10-bit */
> +		if (block->rev & 7)
> +			max_vfreq = data[7] | ((u16)(data[8] & 3) << 8);
> +		else
> +			max_vfreq = data[7];

You might as well add a __packed struct for the data, similar to struct
displayid_tiled_block, to help parsing.

> +
> +		if (!min_vfreq || !max_vfreq)
> +			continue;
> +
> +		info->monitor_range.min_vfreq = min_vfreq;
> +		info->monitor_range.max_vfreq = max_vfreq;
> +
> +		drm_dbg_kms(connector->dev,
> +			    "[CONNECTOR:%d:%s] DisplayID dynamic video timing range: %u-%u Hz\n",
> +			    connector->base.id, connector->name,
> +			    min_vfreq, max_vfreq);

So I'd like all of the above to be in the form:

		if (displayid_is_dynamic_video_timing_block(...))
			displayid_parse_dynamic_video_timing_block(...);

Or something similar. Again, see displayid_is_tiled_block() and its use.

The main point is that I think we should group these displayid_iter*
blocks together more, iterating fewer times and handling all blocks at
once. Note that I'm *not* asking you to do that here, but separating the
parsing from the looping goes a long way in doing that in the future.

BR,
Jani.

> +		break;
> +	}
> +	displayid_iter_end(&iter);
> +}
> +
>  static void drm_get_monitor_range(struct drm_connector *connector,
>  				  const struct drm_edid *drm_edid)
>  {
> @@ -6691,10 +6756,9 @@ static void update_display_info(struct drm_connector *connector,
>  	info->height_mm = edid->height_cm * 10;
>  
>  	drm_get_monitor_range(connector, drm_edid);
> -
> +	drm_get_monitor_range_displayid(connector, drm_edid);

This is way too early. Somewhere near drm_update_mso() call is much
better.

>  	if (edid->revision < 3)
>  		goto out;
> -
>  	if (!drm_edid_is_digital(drm_edid))
>  		goto out;

-- 
Jani Nikula, Intel

[PATCH v2 1/2] drm/edid: populate monitor_range from DisplayID v2r0 Dynamic Video Timing block

[Adriano Vero]

Some eDP panels report their VRR limits only via a DisplayID v2r0
Dynamic Video Timing Range Limits block (tag 0x25), without setting
DRM_EDID_FEATURE_CONTINUOUS_FREQ, causing monitor_range to remain
zeroed after drm_get_monitor_range().

Add displayid_is_dynamic_video_timing_block() and
displayid_parse_dynamic_video_timing(), following the pattern of
displayid_is_tiled_block(), to separate block identification from
parsing. Add a __packed struct for the block payload. Call
drm_get_monitor_range_displayid() from update_display_info() near
drm_update_mso().

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202603300847.vflE6oJO-lkp@intel.com/
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Adriano Vero <litaliano00.contact@gmail.com>
---
 drivers/gpu/drm/drm_displayid_internal.h | 14 +++++
 drivers/gpu/drm/drm_edid.c               | 67 +++++++++++++++++++++++-
 2 files changed, 79 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_displayid_internal.h b/drivers/gpu/drm/drm_displayid_internal.h
index 5b1b32f73..5988e9b89 100644
--- a/drivers/gpu/drm/drm_displayid_internal.h
+++ b/drivers/gpu/drm/drm_displayid_internal.h
@@ -145,6 +145,20 @@ struct displayid_formula_timing_block {
 #define DISPLAYID_VESA_MSO_OVERLAP	GENMASK(3, 0)
 #define DISPLAYID_VESA_MSO_MODE		GENMASK(6, 5)
 
+/*
+ * DisplayID v2r0 §4.9 - Dynamic Video Timing Range Limits Block
+ * num_bytes must be 9, rev bits [7:1] must be zero.
+ * When rev bits [2:0] are nonzero, max_vfreq is a 10-bit value
+ * formed by max_vfreq_lo and bits [1:0] of max_vfreq_hi_flags.
+ */
+struct displayid_dynamic_video_timing_block {
+	struct displayid_block base;
+	u8 reserved[6];
+	u8 min_vfreq;
+	u8 max_vfreq_lo;
+	u8 max_vfreq_hi_flags;
+} __packed;
+
 struct displayid_vesa_vendor_specific_block {
 	struct displayid_block base;
 	u8 oui[3];
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index ff432ac6b..24aa37bea 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -6504,6 +6504,70 @@ void get_monitor_range(const struct detailed_timing *timing, void *c)
 	}
 }
 
+static bool
+displayid_is_dynamic_video_timing_block(const struct displayid_iter *iter,
+					const struct displayid_block *block)
+{
+	return displayid_version(iter) == DISPLAY_ID_STRUCTURE_VER_20 &&
+		block->tag == DATA_BLOCK_2_DYNAMIC_VIDEO_TIMING;
+}
+
+static void
+displayid_parse_dynamic_video_timing(struct drm_connector *connector,
+				     const struct displayid_block *block)
+{
+	const struct displayid_dynamic_video_timing_block *dvt =
+		(const struct displayid_dynamic_video_timing_block *)block;
+	struct drm_display_info *info = &connector->display_info;
+	u16 min_vfreq, max_vfreq;
+
+	/* Already populated from classic EDID descriptor */
+	if (info->monitor_range.min_vfreq && info->monitor_range.max_vfreq)
+		return;
+
+	/* Specification requires exactly 9 payload bytes */
+	if (block->num_bytes != 9)
+		return;
+
+	/* Specification requires rev bits [7:1] to be zero */
+	if (block->rev & 0xFE)
+		return;
+
+	min_vfreq = dvt->min_vfreq;
+
+	/* rev bits [2:0] nonzero: max_vfreq is a 10-bit value */
+	if (block->rev & 0x07)
+		max_vfreq = dvt->max_vfreq_lo | ((u16)(dvt->max_vfreq_hi_flags & 0x3) << 8);
+	else
+		max_vfreq = dvt->max_vfreq_lo;
+
+	if (!min_vfreq || !max_vfreq)
+		return;
+
+	info->monitor_range.min_vfreq = min_vfreq;
+	info->monitor_range.max_vfreq = max_vfreq;
+
+	drm_dbg_kms(connector->dev,
+		    "[CONNECTOR:%d:%s] DisplayID dynamic video timing range: %u-%u Hz\n",
+		    connector->base.id, connector->name,
+		    min_vfreq, max_vfreq);
+}
+
+static void
+drm_get_monitor_range_displayid(struct drm_connector *connector,
+				const struct drm_edid *drm_edid)
+{
+	const struct displayid_block *block;
+	struct displayid_iter iter;
+
+	displayid_iter_edid_begin(drm_edid, &iter);
+	displayid_iter_for_each(block, &iter) {
+		if (displayid_is_dynamic_video_timing_block(&iter, block))
+			displayid_parse_dynamic_video_timing(connector, block);
+	}
+	displayid_iter_end(&iter);
+}
+
 static void drm_get_monitor_range(struct drm_connector *connector,
 				  const struct drm_edid *drm_edid)
 {
@@ -6691,10 +6755,8 @@ static void update_display_info(struct drm_connector *connector,
 	info->height_mm = edid->height_cm * 10;
 
 	drm_get_monitor_range(connector, drm_edid);
-
 	if (edid->revision < 3)
 		goto out;
-
 	if (!drm_edid_is_digital(drm_edid))
 		goto out;
 
@@ -6757,6 +6819,7 @@ static void update_display_info(struct drm_connector *connector,
 		info->color_formats |= DRM_COLOR_FORMAT_YCBCR422;
 
 	drm_update_mso(connector, drm_edid);
+	drm_get_monitor_range_displayid(connector, drm_edid);
 
 out:
 	if (drm_edid_has_internal_quirk(connector, EDID_QUIRK_NON_DESKTOP)) {
-- 
2.47.3

[PATCH v2 2/2] drm/amd/display: remove manual DisplayID VRR parsing from freesync caps

[Adriano Vero]

parse_edid_displayid_vrr() walked raw DisplayID bytes via struct edid*
to find Dynamic Video Timing Range Limits blocks when monitor_range
was zeroed. This is a layering violation.

Now that drm_get_monitor_range_displayid() in the DRM core fills
monitor_range from DisplayID Dynamic Video Timing blocks via the
proper displayid_iter infrastructure, parse_edid_displayid_vrr() is
redundant. Remove it and its drm_edid_raw() call from the VRR path.

drm_edid_raw() remains for parse_amd_vsdb() and parse_hdmi_amd_vsdb()
which read AMD vendor-specific CEA data blocks; those are tracked
separately.

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Rodrigo.Siqueira@amd.com
Signed-off-by: Adriano Vero <litaliano00.contact@gmail.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 61 ++++---------------
 1 file changed, 11 insertions(+), 50 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 085cc98bd..c61d6e1fe 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -13110,49 +13110,6 @@ static bool parse_edid_cea(struct amdgpu_dm_connector *aconnector,
 	return ret;
 }
 
-static void parse_edid_displayid_vrr(struct drm_connector *connector,
-				     const struct edid *edid)
-{
-	u8 *edid_ext = NULL;
-	int i;
-	int j = 0;
-	u16 min_vfreq;
-	u16 max_vfreq;
-
-	if (!edid || !edid->extensions)
-		return;
-
-	/* Find DisplayID extension */
-	for (i = 0; i < edid->extensions; i++) {
-		edid_ext = (void *)(edid + (i + 1));
-		if (edid_ext[0] == DISPLAYID_EXT)
-			break;
-	}
-
-	if (i == edid->extensions)
-		return;
-
-	while (j < EDID_LENGTH) {
-		/* Get dynamic video timing range from DisplayID if available */
-		if (EDID_LENGTH - j > 13 && edid_ext[j] == 0x25	&&
-		    (edid_ext[j+1] & 0xFE) == 0 && (edid_ext[j+2] == 9)) {
-			min_vfreq = edid_ext[j+9];
-			if (edid_ext[j+1] & 7)
-				max_vfreq = edid_ext[j+10] + ((edid_ext[j+11] & 3) << 8);
-			else
-				max_vfreq = edid_ext[j+10];
-
-			if (max_vfreq && min_vfreq) {
-				connector->display_info.monitor_range.max_vfreq = max_vfreq;
-				connector->display_info.monitor_range.min_vfreq = min_vfreq;
-
-				return;
-			}
-		}
-		j++;
-	}
-}
-
 static int parse_amd_vsdb(struct amdgpu_dm_connector *aconnector,
 			  const struct edid *edid, struct amdgpu_hdmi_vsdb_info *vsdb_info)
 {
@@ -13288,13 +13245,17 @@ void amdgpu_dm_update_freesync_caps(struct drm_connector *connector,
 	if (!adev->dm.freesync_module || !dc_supports_vrr(sink->ctx->dce_version))
 		goto update;
 
-	edid = drm_edid_raw(drm_edid); // FIXME: Get rid of drm_edid_raw()
-
-	/* Some eDP panels only have the refresh rate range info in DisplayID */
-	if ((connector->display_info.monitor_range.min_vfreq == 0 ||
-	     connector->display_info.monitor_range.max_vfreq == 0))
-		parse_edid_displayid_vrr(connector, edid);
-
+	/**
+	 * monitor_range is now populated by the DRM core from both classic
+	 * EDID Monitor Range Limits descriptors and DisplayID Dynamic Video
+	 * Timing blocks (tag 0x25) via drm_get_monitor_range_displayid().
+	 * parse_edid_displayid_vrr() has been removed.
+	 *
+	 * drm_edid_raw() is retained only for parse_amd_vsdb() and
+	 * parse_hdmi_amd_vsdb() which read AMD vendor-specific CEA blocks.
+	 * Removing those raw accesses is tracked separately.
+	 */
+	edid = drm_edid_raw(drm_edid); /* TODO: amd/hdmi vsdb refactor */
 	if (edid && (sink->sink_signal == SIGNAL_TYPE_DISPLAY_PORT ||
 		     sink->sink_signal == SIGNAL_TYPE_EDP)) {
 		if (amdgpu_dm_connector->dc_link &&
-- 
2.47.3