drm/i915/guc: add enable_guc_loading parameter

Split the function of "enable_guc_submission" into two separate
options.  The new one ("enable_guc_loading") controls only the
*fetching and loading* of the GuC firmware image. The existing
one is redefined to control only the *use* of the GuC for batch
submission once the firmware is loaded.

In addition, the degree of control has been refined from a simple
bool to an integer key, allowing several options:
-1 (default)     whatever the platform default is
 0  DISABLE      don't load/use the GuC
 1  BEST EFFORT  try to load/use the GuC, fallback if not available
 2  REQUIRE      must load/use the GuC, else leave the GPU wedged

The new platform default (as coded here) will be to attempt to
load the GuC iff the device has a GuC that requires firmware,
but not yet to use it for submission. A later patch will change
to enable it if appropriate.

v4:
    Changed some error-message levels, mostly ERROR->INFO, per
    review comments by Tvrtko Ursulin.

v5:
    Dropped one more error message, disabled GuC submission on
    hypothetical firmware-free devices [Tvrtko Ursulin].

v6:
    Logging tidy by Tvrtko Ursulin:
     * Do not log falling back to execlists when wedging the GPU.
     * Do not log fw load errors when load was disabled by user.
     * Pass down some error code from fw load for log message to
       make more sense.

Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> (v5)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Tested-by: Fiedorowicz, Lukasz <lukasz.fiedorowicz@intel.com>
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> (v5)
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Nick Hoath <nicholas.hoath@intel.com> (v6)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 963f0318d4de5e869f2193ccec8f44b02769d40f..f78d4caf4b7fcb8efd7413aa3b37db9875c7aceb 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -4885,11 +4885,8 @@ i915_gem_init_hw(struct drm_device *dev)
        /* We can't enable contexts until all firmware is loaded */
        if (HAS_GUC(dev)) {
                ret = intel_guc_setup(dev);
-               if (ret) {
-                       DRM_ERROR("Failed to initialize GuC, error %d\n", ret);
-                       ret = -EIO;
+               if (ret)
                        goto out;
-               }
        }
 
        /*

diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index 169242a8adffb87a1372a6139c01a49669a514df..916cd6778cf3640815ecabc639d2a42ca3f8b238 100644 (file)
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -969,7 +969,7 @@ int intel_guc_suspend(struct drm_device *dev)
        struct intel_context *ctx;
        u32 data[3];
 
-       if (!i915.enable_guc_submission)
+       if (guc->guc_fw.guc_fw_load_status != GUC_FIRMWARE_SUCCESS)
                return 0;
 
        ctx = dev_priv->kernel_context;
@@ -995,7 +995,7 @@ int intel_guc_resume(struct drm_device *dev)
        struct intel_context *ctx;
        u32 data[3];
 
-       if (!i915.enable_guc_submission)
+       if (guc->guc_fw.guc_fw_load_status != GUC_FIRMWARE_SUCCESS)
                return 0;
 
        ctx = dev_priv->kernel_context;

diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c
index cd74fb8e93877b95e0647558e60b3e6091fc1840..21a323c01cdb5ffad4e6bc52482ba2e7aaaefce9 100644 (file)
--- a/drivers/gpu/drm/i915/i915_params.c
+++ b/drivers/gpu/drm/i915/i915_params.c
@@ -53,7 +53,8 @@ struct i915_params i915 __read_mostly = {
        .verbose_state_checks = 1,
        .nuclear_pageflip = 0,
        .edp_vswing = 0,
-       .enable_guc_submission = false,
+       .enable_guc_loading = -1,
+       .enable_guc_submission = 0,
        .guc_log_level = -1,
        .enable_dp_mst = true,
        .inject_load_failure = 0,
@@ -193,8 +194,15 @@ MODULE_PARM_DESC(edp_vswing,
                 "(0=use value from vbt [default], 1=low power swing(200mV),"
                 "2=default swing(400mV))");
 
-module_param_named_unsafe(enable_guc_submission, i915.enable_guc_submission, bool, 0400);
-MODULE_PARM_DESC(enable_guc_submission, "Enable GuC submission (default:false)");
+module_param_named_unsafe(enable_guc_loading, i915.enable_guc_loading, int, 0400);
+MODULE_PARM_DESC(enable_guc_loading,
+               "Enable GuC firmware loading "
+               "(-1=auto [default], 0=never, 1=if available, 2=required)");
+
+module_param_named_unsafe(enable_guc_submission, i915.enable_guc_submission, int, 0400);
+MODULE_PARM_DESC(enable_guc_submission,
+               "Enable GuC submission "
+               "(-1=auto, 0=never [default], 1=if available, 2=required)");
 
 module_param_named(guc_log_level, i915.guc_log_level, int, 0400);
 MODULE_PARM_DESC(guc_log_level,

diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h
index dd0d0bbcc05bb147ce9505a889e6d38cd9cf9779..658ce737967191c08446e8f79d7bc6ccf91ff181 100644 (file)
--- a/drivers/gpu/drm/i915/i915_params.h
+++ b/drivers/gpu/drm/i915/i915_params.h
@@ -45,6 +45,8 @@ struct i915_params {
        int enable_ips;
        int invert_brightness;
        int enable_cmd_parser;
+       int enable_guc_loading;
+       int enable_guc_submission;
        int guc_log_level;
        int mmio_debug;
        int edp_vswing;
@@ -56,7 +58,6 @@ struct i915_params {
        bool load_detect_test;
        bool reset;
        bool disable_display;
-       bool enable_guc_submission;
        bool verbose_state_checks;
        bool nuclear_pageflip;
        bool enable_dp_mst;

diff --git a/drivers/gpu/drm/i915/intel_guc_loader.c b/drivers/gpu/drm/i915/intel_guc_loader.c
index 30ec8208dbbc21dfd16530d004d343e78e75ddba..29273e5fee22f8570502c4e31a1342cd351e0619 100644 (file)
--- a/drivers/gpu/drm/i915/intel_guc_loader.c
+++ b/drivers/gpu/drm/i915/intel_guc_loader.c
@@ -402,50 +402,42 @@ int intel_guc_setup(struct drm_device *dev)
 {
        struct drm_i915_private *dev_priv = dev->dev_private;
        struct intel_guc_fw *guc_fw = &dev_priv->guc.guc_fw;
-       int retries, err = 0;
+       const char *fw_path = guc_fw->guc_fw_path;
+       int retries, ret, err;
 
-       if (!i915.enable_guc_submission)
-               return 0;
-
-       DRM_DEBUG_DRIVER("GuC fw status: fetch %s, load %s\n",
+       DRM_DEBUG_DRIVER("GuC fw status: path %s, fetch %s, load %s\n",
+               fw_path,
                intel_guc_fw_status_repr(guc_fw->guc_fw_fetch_status),
                intel_guc_fw_status_repr(guc_fw->guc_fw_load_status));
 
-       direct_interrupts_to_host(dev_priv);
-
-       if (guc_fw->guc_fw_fetch_status == GUC_FIRMWARE_NONE)
-               return 0;
-
-       if (guc_fw->guc_fw_fetch_status == GUC_FIRMWARE_SUCCESS &&
-           guc_fw->guc_fw_load_status == GUC_FIRMWARE_FAIL)
-               return -ENOEXEC;
-
-       guc_fw->guc_fw_load_status = GUC_FIRMWARE_PENDING;
-
-       DRM_DEBUG_DRIVER("GuC fw fetch status %s\n",
-               intel_guc_fw_status_repr(guc_fw->guc_fw_fetch_status));
+       /* Loading forbidden, or no firmware to load? */
+       if (!i915.enable_guc_loading) {
+               err = 0;
+               goto fail;
+       } else if (fw_path == NULL || *fw_path == '\0') {
+               if (*fw_path == '\0')
+                       DRM_INFO("No GuC firmware known for this platform\n");
+               err = -ENODEV;
+               goto fail;
+       }
 
-       switch (guc_fw->guc_fw_fetch_status) {
-       case GUC_FIRMWARE_FAIL:
-               /* something went wrong :( */
+       /* Fetch failed, or already fetched but failed to load? */
+       if (guc_fw->guc_fw_fetch_status != GUC_FIRMWARE_SUCCESS) {
                err = -EIO;
                goto fail;
-
-       case GUC_FIRMWARE_NONE:
-       case GUC_FIRMWARE_PENDING:
-       default:
-               /* "can't happen" */
-               WARN_ONCE(1, "GuC fw %s invalid guc_fw_fetch_status %s [%d]\n",
-                       guc_fw->guc_fw_path,
-                       intel_guc_fw_status_repr(guc_fw->guc_fw_fetch_status),
-                       guc_fw->guc_fw_fetch_status);
-               err = -ENXIO;
+       } else if (guc_fw->guc_fw_load_status == GUC_FIRMWARE_FAIL) {
+               err = -ENOEXEC;
                goto fail;
-
-       case GUC_FIRMWARE_SUCCESS:
-               break;
        }
 
+       direct_interrupts_to_host(dev_priv);
+
+       guc_fw->guc_fw_load_status = GUC_FIRMWARE_PENDING;
+
+       DRM_DEBUG_DRIVER("GuC fw status: fetch %s, load %s\n",
+               intel_guc_fw_status_repr(guc_fw->guc_fw_fetch_status),
+               intel_guc_fw_status_repr(guc_fw->guc_fw_load_status));
+
        err = i915_guc_submission_init(dev);
        if (err)
                goto fail;
@@ -463,7 +455,7 @@ int intel_guc_setup(struct drm_device *dev)
                 */
                err = i915_reset_guc(dev_priv);
                if (err) {
-                       DRM_ERROR("GuC reset failed, err %d\n", err);
+                       DRM_ERROR("GuC reset failed: %d\n", err);
                        goto fail;
                }
 
@@ -474,8 +466,8 @@ int intel_guc_setup(struct drm_device *dev)
                if (--retries == 0)
                        goto fail;
 
-               DRM_INFO("GuC fw load failed, err %d; will reset and "
-                       "retry %d more time(s)\n", err, retries);
+               DRM_INFO("GuC fw load failed: %d; will reset and "
+                        "retry %d more time(s)\n", err, retries);
        }
 
        guc_fw->guc_fw_load_status = GUC_FIRMWARE_SUCCESS;
@@ -497,7 +489,6 @@ int intel_guc_setup(struct drm_device *dev)
        return 0;
 
 fail:
-       DRM_ERROR("GuC firmware load failed, err %d\n", err);
        if (guc_fw->guc_fw_load_status == GUC_FIRMWARE_PENDING)
                guc_fw->guc_fw_load_status = GUC_FIRMWARE_FAIL;
 
@@ -505,7 +496,41 @@ fail:
        i915_guc_submission_disable(dev);
        i915_guc_submission_fini(dev);
 
-       return err;
+       /*
+        * We've failed to load the firmware :(
+        *
+        * Decide whether to disable GuC submission and fall back to
+        * execlist mode, and whether to hide the error by returning
+        * zero or to return -EIO, which the caller will treat as a
+        * nonfatal error (i.e. it doesn't prevent driver load, but
+        * marks the GPU as wedged until reset).
+        */
+       if (i915.enable_guc_loading > 1) {
+               ret = -EIO;
+       } else if (i915.enable_guc_submission > 1) {
+               ret = -EIO;
+       } else {
+               ret = 0;
+       }
+
+       if (err == 0)
+               DRM_INFO("GuC firmware load skipped\n");
+       else if (ret == -EIO)
+               DRM_ERROR("GuC firmware load failed: %d\n", err);
+       else
+               DRM_INFO("GuC firmware load failed: %d\n", err);
+
+       if (i915.enable_guc_submission) {
+               if (fw_path == NULL)
+                       DRM_INFO("GuC submission without firmware not supported\n");
+               if (ret == 0)
+                       DRM_INFO("Falling back to execlist mode\n");
+               else
+                       DRM_ERROR("GuC init failed: %d\n", ret);
+       }
+       i915.enable_guc_submission = 0;
+
+       return ret;
 }
 
 static void guc_fw_fetch(struct drm_device *dev, struct intel_guc_fw *guc_fw)
@@ -644,8 +669,11 @@ void intel_guc_init(struct drm_device *dev)
        struct intel_guc_fw *guc_fw = &dev_priv->guc.guc_fw;
        const char *fw_path;
 
-       if (!HAS_GUC_SCHED(dev))
-               i915.enable_guc_submission = false;
+       /* A negative value means "use platform default" */
+       if (i915.enable_guc_loading < 0)
+               i915.enable_guc_loading = HAS_GUC_UCODE(dev);
+       if (i915.enable_guc_submission < 0)
+               i915.enable_guc_submission = HAS_GUC_SCHED(dev);
 
        if (!HAS_GUC_UCODE(dev)) {
                fw_path = NULL;
@@ -658,26 +686,21 @@ void intel_guc_init(struct drm_device *dev)
                guc_fw->guc_fw_major_wanted = 8;
                guc_fw->guc_fw_minor_wanted = 7;
        } else {
-               i915.enable_guc_submission = false;
                fw_path = "";   /* unknown device */
        }
 
-       if (!i915.enable_guc_submission)
-               return;
-
        guc_fw->guc_dev = dev;
        guc_fw->guc_fw_path = fw_path;
        guc_fw->guc_fw_fetch_status = GUC_FIRMWARE_NONE;
        guc_fw->guc_fw_load_status = GUC_FIRMWARE_NONE;
 
+       /* Early (and silent) return if GuC loading is disabled */
+       if (!i915.enable_guc_loading)
+               return;
        if (fw_path == NULL)
                return;
-
-       if (*fw_path == '\0') {
-               DRM_ERROR("No GuC firmware known for this platform\n");
-               guc_fw->guc_fw_fetch_status = GUC_FIRMWARE_FAIL;
+       if (*fw_path == '\0')
                return;
-       }
 
        guc_fw->guc_fw_fetch_status = GUC_FIRMWARE_PENDING;
        DRM_DEBUG_DRIVER("GuC firmware pending, path %s\n", fw_path);