From 53fd40a90f3c0bdad86ec266ee5df833f54ace39 Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Tue, 12 Sep 2017 11:19:26 +0300 Subject: [PATCH] drm: handle override and firmware EDID at drm_do_get_edid() level MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Handle debugfs override edid and firmware edid at the low level to transparently and completely replace the real edid. Previously, we practically only used the modes from the override EDID, and none of the other data, such as audio parameters. This change also prevents actual EDID reads when the EDID is to be overridden, but retains the DDC probe. This is useful if the reason for preferring override EDID are problems with reading the data, or corruption of the data. Move firmware EDID loading from helper to core, as the functionality moves to lower level as well. This will result in a change of module parameter from drm_kms_helper.edid_firmware to drm.edid_firmware, which arguably makes more sense anyway. Some future work remains related to override and firmware EDID validation. Like before, no validation is done for override EDID. The firmware EDID is validated separately in the loader. Some unification and deduplication would be in order, to validate all of them at the drm_do_get_edid() level, like "real" EDIDs. v2: move firmware loading to core v3: rebase, commit message refresh Cc: Abdiel Janulgue Cc: Daniel Vetter Cc: Ville Syrjälä Tested-by: Abdiel Janulgue Reviewed-by: Ville Syrjälä Acked-by: Dave Airlie Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/1e8a710bcac46e5136c1a7b430074893c81f364a.1505203831.git.jani.nikula@intel.com --- .../admin-guide/kernel-parameters.txt | 2 +- drivers/gpu/drm/Kconfig | 2 +- drivers/gpu/drm/Makefile | 2 +- drivers/gpu/drm/drm_edid.c | 15 +++++++++++++++ drivers/gpu/drm/drm_probe_helper.c | 19 +------------------ 5 files changed, 19 insertions(+), 21 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index d9c171ce4190..9b393c29953f 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -854,7 +854,7 @@ The filter can be disabled or changed to another driver later using sysfs. - drm_kms_helper.edid_firmware=[:][,[:]] + drm.edid_firmware=[:][,[:]] Broken monitors, graphic adapters, KVMs and EDIDless panels may send no or incorrect EDID data sets. This parameter allows to specify an EDID data sets diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig index c5e1a8409285..c9f09fc298bb 100644 --- a/drivers/gpu/drm/Kconfig +++ b/drivers/gpu/drm/Kconfig @@ -110,7 +110,7 @@ config DRM_FBDEV_OVERALLOC config DRM_LOAD_EDID_FIRMWARE bool "Allow to specify an EDID data set instead of probing for it" - depends on DRM_KMS_HELPER + depends on DRM help Say Y here, if you want to use EDID data to be loaded from the /lib/firmware directory or one of the provided built-in diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile index df923119ac36..0ee184f56a60 100644 --- a/drivers/gpu/drm/Makefile +++ b/drivers/gpu/drm/Makefile @@ -28,6 +28,7 @@ drm-$(CONFIG_DRM_PANEL) += drm_panel.o drm-$(CONFIG_OF) += drm_of.o drm-$(CONFIG_AGP) += drm_agpsupport.o drm-$(CONFIG_DEBUG_FS) += drm_debugfs.o drm_debugfs_crc.o +drm-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o drm_kms_helper-y := drm_crtc_helper.o drm_dp_helper.o drm_probe_helper.o \ drm_plane_helper.o drm_dp_mst_topology.o drm_atomic_helper.o \ @@ -36,7 +37,6 @@ drm_kms_helper-y := drm_crtc_helper.o drm_dp_helper.o drm_probe_helper.o \ drm_scdc_helper.o drm_gem_framebuffer_helper.o drm_kms_helper-$(CONFIG_DRM_PANEL_BRIDGE) += bridge/panel.o -drm_kms_helper-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o drm_kms_helper-$(CONFIG_DRM_FBDEV_EMULATION) += drm_fb_helper.o drm_kms_helper-$(CONFIG_DRM_KMS_CMA_HELPER) += drm_fb_cma_helper.o drm_kms_helper-$(CONFIG_DRM_DP_AUX_CHARDEV) += drm_dp_aux_dev.o diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 6bb6337be920..00ddabfbf980 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -1533,6 +1533,10 @@ static void connector_bad_edid(struct drm_connector *connector, * level, drivers must make all reasonable efforts to expose it as an I2C * adapter and use drm_get_edid() instead of abusing this function. * + * The EDID may be overridden using debugfs override_edid or firmare EDID + * (drm_load_edid_firmware() and drm.edid_firmware parameter), in this priority + * order. Having either of them bypasses actual EDID reads. + * * Return: Pointer to valid EDID or NULL if we couldn't find any. */ struct edid *drm_do_get_edid(struct drm_connector *connector, @@ -1542,6 +1546,17 @@ struct edid *drm_do_get_edid(struct drm_connector *connector, { int i, j = 0, valid_extensions = 0; u8 *edid, *new; + struct edid *override = NULL; + + if (connector->override_edid) + override = drm_edid_duplicate((const struct edid *) + connector->edid_blob_ptr->data); + + if (!override) + override = drm_load_edid_firmware(connector); + + if (!IS_ERR_OR_NULL(override)) + return override; if ((edid = kmalloc(EDID_LENGTH, GFP_KERNEL)) == NULL) return NULL; diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c index 904966cde32b..5840aabbf24e 100644 --- a/drivers/gpu/drm/drm_probe_helper.c +++ b/drivers/gpu/drm/drm_probe_helper.c @@ -353,8 +353,6 @@ EXPORT_SYMBOL(drm_helper_probe_detect); * drm_mode_probed_add(). New modes start their life with status as OK. * Modes are added from a single source using the following priority order. * - * - debugfs 'override_edid' (used for testing only) - * - firmware EDID (drm_load_edid_firmware()) * - &drm_connector_helper_funcs.get_modes vfunc * - if the connector status is connector_status_connected, standard * VESA DMT modes up to 1024x768 are automatically added @@ -483,22 +481,7 @@ int drm_helper_probe_single_connector_modes(struct drm_connector *connector, goto prune; } - if (connector->override_edid) { - struct edid *edid = (struct edid *) connector->edid_blob_ptr->data; - - count = drm_add_edid_modes(connector, edid); - drm_edid_to_eld(connector, edid); - } else { - struct edid *edid = drm_load_edid_firmware(connector); - if (!IS_ERR_OR_NULL(edid)) { - drm_mode_connector_update_edid_property(connector, edid); - count = drm_add_edid_modes(connector, edid); - drm_edid_to_eld(connector, edid); - kfree(edid); - } - if (count == 0) - count = (*connector_funcs->get_modes)(connector); - } + count = (*connector_funcs->get_modes)(connector); if (count == 0 && connector->status == connector_status_connected) count = drm_add_modes_noedid(connector, 1024, 768);