drm/i915/guc: doorbell checking cleanup

A collection of very small cleanups/improvements around doorbell checking
that do not deserve their own patch:

- Move doorbell-related HW defs to intel_guc_reg.h

- use GUC_NUM_DOORBELLS instead of GUC_DOORBELL_INVALID where
  appropriate

- do not stop on error in guc_verify_doorbells

- do not print drbreg on error: the only content of the register
  apart from the valid bit is the lower part of the physical memory
  address, which we can't use even if valid because we don't know
  which descriptor it came from (since the doorbell is in an unexpected
  state)

- Move the checking of doorbell valid bit to a common helper.

v2: add more cleanups (move defs, use GUC_NUM_DOORBELLS, don't stop in
    guc_verify_doorbells) (Michal)

v3: move more things to intel_guc_reg, redefine
    GUC_DOORBELL_INVALID (Michal), drop guc_doorbell_qw since it just
    duplicates guc_doorbell_info

Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20181022230427.5616-3-daniele.ceraolospurio@intel.com

1 files changed, 16 insertions, 11 deletions

diff --git a/drivers/gpu/drm/i915/intel_guc_submission.c b/drivers/gpu/drm/i915/intel_guc_submission.c
index 8c3b5a9facee..1570dcbe249c 100644
--- a/drivers/gpu/drm/i915/intel_guc_submission.c
+++ b/drivers/gpu/drm/i915/intel_guc_submission.c
@@ -192,6 +192,14 @@ static struct guc_doorbell_info *__get_doorbell(struct intel_guc_client *client)
 	return client->vaddr + client->doorbell_offset;
 }
 
+static bool __doorbell_valid(struct intel_guc *guc, u16 db_id)
+{
+	struct drm_i915_private *dev_priv = guc_to_i915(guc);
+
+	GEM_BUG_ON(db_id >= GUC_NUM_DOORBELLS);
+	return I915_READ(GEN8_DRBREGL(db_id)) & GEN8_DRB_VALID;
+}
+
 static void __init_doorbell(struct intel_guc_client *client)
 {
 	struct guc_doorbell_info *doorbell;
@@ -203,7 +211,6 @@ static void __init_doorbell(struct intel_guc_client *client)
 
 static void __fini_doorbell(struct intel_guc_client *client)
 {
-	struct drm_i915_private *dev_priv = guc_to_i915(client->guc);
 	struct guc_doorbell_info *doorbell;
 	u16 db_id = client->doorbell_id;
 
@@ -214,7 +221,7 @@ static void __fini_doorbell(struct intel_guc_client *client)
 	 * to go to zero after updating db_status before we call the GuC to
 	 * release the doorbell
 	 */
-	if (wait_for_us(!(I915_READ(GEN8_DRBREGL(db_id)) & GEN8_DRB_VALID), 10))
+	if (wait_for_us(!__doorbell_valid(client->guc, db_id), 10))
 		WARN_ONCE(true, "Doorbell never became invalid after disable\n");
 }
 
@@ -866,33 +873,31 @@ guc_reset_prepare(struct intel_engine_cs *engine)
 /* Check that a doorbell register is in the expected state */
 static bool doorbell_ok(struct intel_guc *guc, u16 db_id)
 {
-	struct drm_i915_private *dev_priv = guc_to_i915(guc);
-	u32 drbregl;
 	bool valid;
 
-	GEM_BUG_ON(db_id >= GUC_DOORBELL_INVALID);
+	GEM_BUG_ON(db_id >= GUC_NUM_DOORBELLS);
 
-	drbregl = I915_READ(GEN8_DRBREGL(db_id));
-	valid = drbregl & GEN8_DRB_VALID;
+	valid = __doorbell_valid(guc, db_id);
 
 	if (test_bit(db_id, guc->doorbell_bitmap) == valid)
 		return true;
 
-	DRM_DEBUG_DRIVER("Doorbell %d has unexpected state (0x%x): valid=%s\n",
-			 db_id, drbregl, yesno(valid));
+	DRM_DEBUG_DRIVER("Doorbell %u has unexpected state: valid=%s\n",
+			 db_id, yesno(valid));
 
 	return false;
 }
 
 static bool guc_verify_doorbells(struct intel_guc *guc)
 {
+	bool doorbells_ok = true;
 	u16 db_id;
 
 	for (db_id = 0; db_id < GUC_NUM_DOORBELLS; ++db_id)
 		if (!doorbell_ok(guc, db_id))
-			return false;
+			doorbells_ok = false;
 
-	return true;
+	return doorbells_ok;
 }
 
 /**