From: Jani Nikula Date: Thu, 17 Aug 2017 11:52:09 +0000 (+0300) Subject: drm/i915/opregion: let user specify override VBT via firmware load X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=ab3595bc4ff328ec90d20714f8e2674f3abfa2cd;p=linux.git drm/i915/opregion: let user specify override VBT via firmware load Sometimes it would be most enlightening to debug systems by replacing the VBT to be used. For example, in the referenced bug the BIOS provides different VBT depending on the boot mode (UEFI vs. legacy). It would be interesting to try the failing boot mode with the VBT from the working boot, and see if that makes a difference. Add a module parameter to load the VBT using the firmware loader, not unlike the EDID firmware mechanism. As a starting point for experimenting, one can pick up the BIOS provided VBT from /sys/kernel/debug/dri/0/i915_opregion/i915_vbt. v2: clarify firmware load return value check (Bob) v3: kfree the loaded firmware blob References: https://bugs.freedesktop.org/show_bug.cgi?id=97822#c83 Reviewed-by: Bob Paauwe Acked-by: Daniel Vetter Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20170817115209.25912-1-jani.nikula@intel.com --- diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 6c25c8520c872..3ee4fd2a9b41c 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -646,6 +646,7 @@ struct intel_opregion { u32 swsci_sbcb_sub_functions; struct opregion_asle *asle; void *rvda; + void *vbt_firmware; const void *vbt; u32 vbt_size; u32 *lid_state; diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c index 14e2c2e57f96a..8ab003dca1131 100644 --- a/drivers/gpu/drm/i915/i915_params.c +++ b/drivers/gpu/drm/i915/i915_params.c @@ -118,6 +118,10 @@ MODULE_PARM_DESC(vbt_sdvo_panel_type, module_param_named_unsafe(reset, i915.reset, int, 0600); MODULE_PARM_DESC(reset, "Attempt GPU resets (0=disabled, 1=full gpu reset, 2=engine reset [default])"); +module_param_named_unsafe(vbt_firmware, i915.vbt_firmware, charp, 0400); +MODULE_PARM_DESC(vbt_firmware, + "Load VBT from specified file under /lib/firmware"); + #if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR) module_param_named(error_capture, i915.error_capture, bool, 0600); MODULE_PARM_DESC(error_capture, diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h index febbfdbd30bdb..ac844709c97e7 100644 --- a/drivers/gpu/drm/i915/i915_params.h +++ b/drivers/gpu/drm/i915/i915_params.h @@ -28,6 +28,7 @@ #include /* for __read_mostly */ #define I915_PARAMS_FOR_EACH(func) \ + func(char *, vbt_firmware); \ func(int, modeset); \ func(int, panel_ignore_lid); \ func(int, semaphores); \ diff --git a/drivers/gpu/drm/i915/intel_opregion.c b/drivers/gpu/drm/i915/intel_opregion.c index 2bd03001cc709..98154efcb2f41 100644 --- a/drivers/gpu/drm/i915/intel_opregion.c +++ b/drivers/gpu/drm/i915/intel_opregion.c @@ -27,6 +27,7 @@ #include #include +#include #include #include @@ -829,6 +830,10 @@ void intel_opregion_unregister(struct drm_i915_private *dev_priv) memunmap(opregion->rvda); opregion->rvda = NULL; } + if (opregion->vbt_firmware) { + kfree(opregion->vbt_firmware); + opregion->vbt_firmware = NULL; + } opregion->header = NULL; opregion->acpi = NULL; opregion->swsci = NULL; @@ -912,6 +917,43 @@ static const struct dmi_system_id intel_no_opregion_vbt[] = { { } }; +static int intel_load_vbt_firmware(struct drm_i915_private *dev_priv) +{ + struct intel_opregion *opregion = &dev_priv->opregion; + const struct firmware *fw = NULL; + const char *name = i915.vbt_firmware; + int ret; + + if (!name || !*name) + return -ENOENT; + + ret = request_firmware(&fw, name, &dev_priv->drm.pdev->dev); + if (ret) { + DRM_ERROR("Requesting VBT firmware \"%s\" failed (%d)\n", + name, ret); + return ret; + } + + if (intel_bios_is_valid_vbt(fw->data, fw->size)) { + opregion->vbt_firmware = kmemdup(fw->data, fw->size, GFP_KERNEL); + if (opregion->vbt_firmware) { + DRM_DEBUG_KMS("Found valid VBT firmware \"%s\"\n", name); + opregion->vbt = opregion->vbt_firmware; + opregion->vbt_size = fw->size; + ret = 0; + } else { + ret = -ENOMEM; + } + } else { + DRM_DEBUG_KMS("Invalid VBT firmware \"%s\"\n", name); + ret = -EINVAL; + } + + release_firmware(fw); + + return ret; +} + int intel_opregion_setup(struct drm_i915_private *dev_priv) { struct intel_opregion *opregion = &dev_priv->opregion; @@ -974,6 +1016,9 @@ int intel_opregion_setup(struct drm_i915_private *dev_priv) if (mboxes & MBOX_ASLE_EXT) DRM_DEBUG_DRIVER("ASLE extension supported\n"); + if (intel_load_vbt_firmware(dev_priv) == 0) + goto out; + if (dmi_check_system(intel_no_opregion_vbt)) goto out;