diff mbox series

[v6,10/10] drm/amd/display: Fetch the EDID from _DDC if available for eDP

Message ID 20240911213537.2338164-11-superm1@kernel.org (mailing list archive)
State New, archived
Headers show
Series drm/amd/display: Use drm_edid for more code | expand

Commit Message

Mario Limonciello Sept. 11, 2024, 9:35 p.m. UTC 
From: Mario Limonciello <mario.limonciello@amd.com>

Some manufacturers have intentionally put an EDID that differs from
the EDID on the internal panel on laptops.

Attempt to fetch this EDID if it exists and prefer it over the EDID
that is provided by the panel. If a user prefers to use the EDID from
the panel, offer a DC debugging parameter that would disable this.

Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 .../amd/display/amdgpu_dm/amdgpu_dm_helpers.c | 63 ++++++++++++++++++-
 drivers/gpu/drm/amd/include/amd_shared.h      |  1 +
 2 files changed, 63 insertions(+), 1 deletion(-)

Comments

kernel test robot Sept. 16, 2024, 4:30 a.m. UTC | #1 
Hi Mario,

kernel test robot noticed the following build warnings:

[auto build test WARNING on amd-pstate/linux-next]
[also build test WARNING on amd-pstate/bleeding-edge linus/master v6.11]
[cannot apply to next-20240913]
[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/Mario-Limonciello/drm-amd-display-switch-amdgpu_dm_connector-to-use-struct-drm_edid/20240912-093827
base:   https://git.kernel.org/pub/scm/linux/kernel/git/superm1/linux.git linux-next
patch link:    https://lore.kernel.org/r/20240911213537.2338164-11-superm1%40kernel.org
patch subject: [PATCH v6 10/10] drm/amd/display: Fetch the EDID from _DDC if available for eDP
config: alpha-allyesconfig (https://download.01.org/0day-ci/archive/20240916/202409161225.xuQVKkoR-lkp@intel.com/config)
compiler: alpha-linux-gcc (GCC) 13.3.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240916/202409161225.xuQVKkoR-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/202409161225.xuQVKkoR-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_helpers.c: In function 'dm_helpers_probe_acpi_edid':
>> drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_helpers.c:883:28: warning: unused variable 'ddev' [-Wunused-variable]
     883 |         struct drm_device *ddev = connector->dev;
         |                            ^~~~


vim +/ddev +883 drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_helpers.c

   878	
   879	static int
   880	dm_helpers_probe_acpi_edid(void *data, u8 *buf, unsigned int block, size_t len)
   881	{
   882		struct drm_connector *connector = data;
 > 883		struct drm_device *ddev = connector->dev;
   884		struct acpi_device *acpidev = ACPI_COMPANION(ddev->dev);
   885		unsigned char start = block * EDID_LENGTH;
   886		void *edid;
   887		int r;
   888	
   889		if (!acpidev)
   890			return -ENODEV;
   891	
   892		/* fetch the entire edid from BIOS */
   893		r = acpi_video_get_edid(acpidev, ACPI_VIDEO_DISPLAY_LCD, -1, &edid);
   894		if (r < 0) {
   895			DRM_DEBUG_KMS("Failed to get EDID from ACPI: %d\n", r);
   896			return r;
   897		}
   898		if (len > r || start > r || start + len > r) {
   899			r = -EINVAL;
   900			goto cleanup;
   901		}
   902	
   903		memcpy(buf, edid + start, len);
   904		r = 0;
   905	
   906	cleanup:
   907		kfree(edid);
   908	
   909		return r;
   910	}
   911
kernel test robot Sept. 19, 2024, 4:05 a.m. UTC | #2 
Hi Mario,

kernel test robot noticed the following build errors:

[auto build test ERROR on amd-pstate/linux-next]
[also build test ERROR on amd-pstate/bleeding-edge linus/master v6.11]
[cannot apply to next-20240918]
[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/Mario-Limonciello/drm-amd-display-switch-amdgpu_dm_connector-to-use-struct-drm_edid/20240912-093827
base:   https://git.kernel.org/pub/scm/linux/kernel/git/superm1/linux.git linux-next
patch link:    https://lore.kernel.org/r/20240911213537.2338164-11-superm1%40kernel.org
patch subject: [PATCH v6 10/10] drm/amd/display: Fetch the EDID from _DDC if available for eDP
config: arm64-randconfig-003-20240918 (https://download.01.org/0day-ci/archive/20240919/202409191128.4bvJysve-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 14.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240919/202409191128.4bvJysve-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/202409191128.4bvJysve-lkp@intel.com/

All errors (new ones prefixed by >>):

   drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_helpers.c: In function 'dm_helpers_probe_acpi_edid':
>> drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_helpers.c:883:28: error: unused variable 'ddev' [-Werror=unused-variable]
     883 |         struct drm_device *ddev = connector->dev;
         |                            ^~~~
   cc1: all warnings being treated as errors

Kconfig warnings: (for reference only)
   WARNING: unmet direct dependencies detected for FB_IOMEM_HELPERS
   Depends on [n]: HAS_IOMEM [=y] && FB_CORE [=n]
   Selected by [m]:
   - DRM_XE_DISPLAY [=y] && HAS_IOMEM [=y] && DRM [=y] && DRM_XE [=m] && DRM_XE [=m]=m [=m]


vim +/ddev +883 drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_helpers.c

   878	
   879	static int
   880	dm_helpers_probe_acpi_edid(void *data, u8 *buf, unsigned int block, size_t len)
   881	{
   882		struct drm_connector *connector = data;
 > 883		struct drm_device *ddev = connector->dev;
   884		struct acpi_device *acpidev = ACPI_COMPANION(ddev->dev);
   885		unsigned char start = block * EDID_LENGTH;
   886		void *edid;
   887		int r;
   888	
   889		if (!acpidev)
   890			return -ENODEV;
   891	
   892		/* fetch the entire edid from BIOS */
   893		r = acpi_video_get_edid(acpidev, ACPI_VIDEO_DISPLAY_LCD, -1, &edid);
   894		if (r < 0) {
   895			DRM_DEBUG_KMS("Failed to get EDID from ACPI: %d\n", r);
   896			return r;
   897		}
   898		if (len > r || start > r || start + len > r) {
   899			r = -EINVAL;
   900			goto cleanup;
   901		}
   902	
   903		memcpy(buf, edid + start, len);
   904		r = 0;
   905	
   906	cleanup:
   907		kfree(edid);
   908	
   909		return r;
   910	}
   911
diff mbox series

Patch

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index 1118986bb3e2..26d5fff6e185 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -23,6 +23,8 @@ 
  *
  */
 
+#include <acpi/video.h>
+
 #include <linux/string.h>
 #include <linux/acpi.h>
 #include <linux/i2c.h>
@@ -874,6 +876,61 @@  bool dm_helpers_is_dp_sink_present(struct dc_link *link)
 	return dp_sink_present;
 }
 
+static int
+dm_helpers_probe_acpi_edid(void *data, u8 *buf, unsigned int block, size_t len)
+{
+	struct drm_connector *connector = data;
+	struct drm_device *ddev = connector->dev;
+	struct acpi_device *acpidev = ACPI_COMPANION(ddev->dev);
+	unsigned char start = block * EDID_LENGTH;
+	void *edid;
+	int r;
+
+	if (!acpidev)
+		return -ENODEV;
+
+	/* fetch the entire edid from BIOS */
+	r = acpi_video_get_edid(acpidev, ACPI_VIDEO_DISPLAY_LCD, -1, &edid);
+	if (r < 0) {
+		DRM_DEBUG_KMS("Failed to get EDID from ACPI: %d\n", r);
+		return r;
+	}
+	if (len > r || start > r || start + len > r) {
+		r = -EINVAL;
+		goto cleanup;
+	}
+
+	memcpy(buf, edid + start, len);
+	r = 0;
+
+cleanup:
+	kfree(edid);
+
+	return r;
+}
+
+static const struct drm_edid *
+dm_helpers_read_acpi_edid(struct amdgpu_dm_connector *aconnector)
+{
+	struct drm_connector *connector = &aconnector->base;
+
+	if (amdgpu_dc_debug_mask & DC_DISABLE_ACPI_EDID)
+		return NULL;
+
+	switch (connector->connector_type) {
+	case DRM_MODE_CONNECTOR_LVDS:
+	case DRM_MODE_CONNECTOR_eDP:
+		break;
+	default:
+		return NULL;
+	}
+
+	if (connector->force == DRM_FORCE_OFF)
+		return NULL;
+
+	return drm_edid_read_custom(connector, dm_helpers_probe_acpi_edid, connector);
+}
+
 enum dc_edid_status dm_helpers_read_local_edid(
 		struct dc_context *ctx,
 		struct dc_link *link,
@@ -896,7 +953,11 @@  enum dc_edid_status dm_helpers_read_local_edid(
 	 * do check sum and retry to make sure read correct edid.
 	 */
 	do {
-		drm_edid = drm_edid_read_ddc(connector, ddc);
+		drm_edid = dm_helpers_read_acpi_edid(aconnector);
+		if (drm_edid)
+			DRM_DEBUG_KMS("Using ACPI provided EDID for %s\n", connector->name);
+		else
+			drm_edid = drm_edid_read_ddc(connector, ddc);
 		drm_edid_connector_update(connector, drm_edid);
 		aconnector->drm_edid = drm_edid;
 
diff --git a/drivers/gpu/drm/amd/include/amd_shared.h b/drivers/gpu/drm/amd/include/amd_shared.h
index f5b725f10a7c..9702eba767f9 100644
--- a/drivers/gpu/drm/amd/include/amd_shared.h
+++ b/drivers/gpu/drm/amd/include/amd_shared.h
@@ -264,6 +264,7 @@  enum DC_DEBUG_MASK {
 	DC_DISABLE_PSR_SU = 0x200,
 	DC_DISABLE_REPLAY = 0x400,
 	DC_DISABLE_IPS = 0x800,
+	DC_DISABLE_ACPI_EDID = 0x1000,
 };
 
 enum amd_dpm_forced_level;