From f10d69a76b11c9a2137393b042d18cd903dbd9e3 Mon Sep 17 00:00:00 2001 From: Dave Gordon Date: Mon, 13 Jun 2016 17:57:33 +0100 Subject: [PATCH] drm/i915/guc: replace assign_doorbell() with select_doorbell_register() This version doesn't update the doorbell bitmap, as that will be done when the selected doorbell is associated with a client. The call is now slightly earlier, just on the general principle that potentially-failing operations should be done as early as possible, to eliminate late failures and simplify recovery. Suggested-by: Tvrtko Ursulin Signed-off-by: Dave Gordon Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Signed-off-by: Tvrtko Ursulin --- drivers/gpu/drm/i915/i915_guc_submission.c | 62 +++++++++++----------- 1 file changed, 31 insertions(+), 31 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c index 62bf4bdbe90a..a25250570bb5 100644 --- a/drivers/gpu/drm/i915/i915_guc_submission.c +++ b/drivers/gpu/drm/i915/i915_guc_submission.c @@ -232,6 +232,32 @@ static void guc_disable_doorbell(struct intel_guc *guc, /* XXX: wait for workqueue to drain */ } +static uint16_t +select_doorbell_register(struct intel_guc *guc, uint32_t priority) +{ + /* + * The bitmap tracks which doorbell registers are currently in use. + * It is split into two halves; the first half is used for normal + * priority contexts, the second half for high-priority ones. + * Note that logically higher priorities are numerically less than + * normal ones, so the test below means "is it high-priority?" + */ + const bool hi_pri = (priority <= GUC_CTX_PRIORITY_HIGH); + const uint16_t half = GUC_MAX_DOORBELLS / 2; + const uint16_t start = hi_pri ? half : 0; + const uint16_t end = start + half; + uint16_t id; + + id = find_next_zero_bit(guc->doorbell_bitmap, end, start); + if (id == end) + id = GUC_INVALID_DOORBELL_ID; + + DRM_DEBUG_DRIVER("assigned %s priority doorbell id 0x%x\n", + hi_pri ? "high" : "normal", id); + + return id; +} + /* * Select, assign and relase doorbell cachelines * @@ -256,32 +282,6 @@ static uint32_t select_doorbell_cacheline(struct intel_guc *guc) return offset; } -static uint16_t assign_doorbell(struct intel_guc *guc, uint32_t priority) -{ - /* - * The bitmap is split into two halves; the first half is used for - * normal priority contexts, the second half for high-priority ones. - * Note that logically higher priorities are numerically less than - * normal ones, so the test below means "is it high-priority?" - */ - const bool hi_pri = (priority <= GUC_CTX_PRIORITY_HIGH); - const uint16_t half = GUC_MAX_DOORBELLS / 2; - const uint16_t start = hi_pri ? half : 0; - const uint16_t end = start + half; - uint16_t id; - - id = find_next_zero_bit(guc->doorbell_bitmap, end, start); - if (id == end) - id = GUC_INVALID_DOORBELL_ID; - else - __set_bit(id, guc->doorbell_bitmap); - - DRM_DEBUG_DRIVER("assigned %s priority doorbell id 0x%x\n", - hi_pri ? "high" : "normal", id); - - return id; -} - /* * Initialise the process descriptor shared with the GuC firmware. */ @@ -742,6 +742,11 @@ guc_client_alloc(struct drm_i915_private *dev_priv, client->wq_offset = GUC_DB_SIZE; client->wq_size = GUC_WQ_SIZE; + db_id = select_doorbell_register(guc, client->priority); + if (db_id == GUC_INVALID_DOORBELL_ID) + /* XXX: evict a doorbell instead? */ + goto err; + client->doorbell_offset = select_doorbell_cacheline(guc); /* @@ -754,11 +759,6 @@ guc_client_alloc(struct drm_i915_private *dev_priv, else client->proc_desc_offset = (GUC_DB_SIZE / 2); - db_id = assign_doorbell(guc, client->priority); - if (db_id == GUC_INVALID_DOORBELL_ID) - /* XXX: evict a doorbell instead */ - goto err; - guc_init_proc_desc(guc, client); guc_init_ctx_desc(guc, client); if (guc_init_doorbell(guc, client, db_id)) -- 2.20.1