[v3 PATCH 1/2] drm/i915/guc: Replace CTB array with explicit members

[Matthew Brost]

From: Michal Wajdeczko <michal.wajdeczko at intel.com>

Upcoming GuC firmware will always require just two CTBs and we
also plan to configure them with different sizes, so definining
them as array is no longer suitable.

v2: Use %p for ptrdiff print
v3: Use %tx for ptrdiff print

Signed-off-by: Michal Wajdeczko <michal.wajdeczko at intel.com>
Signed-off-by: Matthew Brost <matthew.brost at intel.com>
Reviewed-by: Matthew Brost <matthew.brost at intel.com>
Reported-by: kernel test robot <lkp at intel.com>
---
 drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c | 46 ++++++++++++-----------
 drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h |  7 +++-
 2 files changed, 30 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
index 34c582105860..ec795d7c3a7d 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.c
@@ -168,10 +168,10 @@ int intel_guc_ct_init(struct intel_guc_ct *ct)
 	struct intel_guc *guc = ct_to_guc(ct);
 	struct guc_ct_buffer_desc *desc;
 	u32 blob_size;
+	u32 cmds_size;
 	void *blob;
 	u32 *cmds;
 	int err;
-	int i;
 
 	GEM_BUG_ON(ct->vma);
 
@@ -207,15 +207,23 @@ int intel_guc_ct_init(struct intel_guc_ct *ct)
 
 	CT_DEBUG(ct, "base=%#x size=%u\n", intel_guc_ggtt_offset(guc, ct->vma), blob_size);
 
-	/* store pointers to desc and cmds */
-	for (i = 0; i < ARRAY_SIZE(ct->ctbs); i++) {
-		GEM_BUG_ON((i !=  CTB_SEND) && (i != CTB_RECV));
+	/* store pointers to desc and cmds for send ctb */
+	desc = blob;
+	cmds = blob + PAGE_SIZE / 2;
+	cmds_size = PAGE_SIZE / 4;
+	CT_DEBUG(ct, "%s desc %#tx cmds %#tx size %u\n", "send",
+		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size);
 
-		desc = blob + PAGE_SIZE / 4 * i;
-		cmds = blob + PAGE_SIZE / 4 * i + PAGE_SIZE / 2;
+	guc_ct_buffer_init(&ct->ctbs.send, desc, cmds, cmds_size);
 
-		guc_ct_buffer_init(&ct->ctbs[i], desc, cmds, PAGE_SIZE / 4);
-	}
+	/* store pointers to desc and cmds for recv ctb */
+	desc = blob + PAGE_SIZE / 4;
+	cmds = blob + PAGE_SIZE / 4 + PAGE_SIZE / 2;
+	cmds_size = PAGE_SIZE / 4;
+	CT_DEBUG(ct, "%s desc %#tx cmds %#tx size %u\n", "recv",
+		 ptrdiff(desc, blob), ptrdiff(cmds, blob), cmds_size);
+
+	guc_ct_buffer_init(&ct->ctbs.recv, desc, cmds, cmds_size);
 
 	return 0;
 }
@@ -246,7 +254,6 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
 	u32 base, cmds;
 	void *blob;
 	int err;
-	int i;
 
 	GEM_BUG_ON(ct->enabled);
 
@@ -257,28 +264,25 @@ int intel_guc_ct_enable(struct intel_guc_ct *ct)
 
 	/* blob should start with send descriptor */
 	blob = __px_vaddr(ct->vma->obj);
-	GEM_BUG_ON(blob != ct->ctbs[CTB_SEND].desc);
+	GEM_BUG_ON(blob != ct->ctbs.send.desc);
 
 	/* (re)initialize descriptors */
-	for (i = 0; i < ARRAY_SIZE(ct->ctbs); i++) {
-		GEM_BUG_ON((i != CTB_SEND) && (i != CTB_RECV));
+	cmds = base + ptrdiff(ct->ctbs.send.cmds, blob);
+	guc_ct_buffer_reset(&ct->ctbs.send, cmds);
 
-		cmds = base + ptrdiff(ct->ctbs[i].cmds, blob);
-		CT_DEBUG(ct, "%d: cmds addr=%#x\n", i, cmds);
-
-		guc_ct_buffer_reset(&ct->ctbs[i], cmds);
-	}
+	cmds = base + ptrdiff(ct->ctbs.recv.cmds, blob);
+	guc_ct_buffer_reset(&ct->ctbs.recv, cmds);
 
 	/*
 	 * Register both CT buffers starting with RECV buffer.
 	 * Descriptors are in first half of the blob.
 	 */
-	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs[CTB_RECV].desc, blob),
+	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs.recv.desc, blob),
 				 INTEL_GUC_CT_BUFFER_TYPE_RECV);
 	if (unlikely(err))
 		goto err_out;
 
-	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs[CTB_SEND].desc, blob),
+	err = ct_register_buffer(ct, base + ptrdiff(ct->ctbs.send.desc, blob),
 				 INTEL_GUC_CT_BUFFER_TYPE_SEND);
 	if (unlikely(err))
 		goto err_deregister;
@@ -341,7 +345,7 @@ static int ct_write(struct intel_guc_ct *ct,
 		    u32 len /* in dwords */,
 		    u32 fence)
 {
-	struct intel_guc_ct_buffer *ctb = &ct->ctbs[CTB_SEND];
+	struct intel_guc_ct_buffer *ctb = &ct->ctbs.send;
 	struct guc_ct_buffer_desc *desc = ctb->desc;
 	u32 head = desc->head;
 	u32 tail = desc->tail;
@@ -557,7 +561,7 @@ static inline bool ct_header_is_response(u32 header)
 
 static int ct_read(struct intel_guc_ct *ct, u32 *data)
 {
-	struct intel_guc_ct_buffer *ctb = &ct->ctbs[CTB_RECV];
+	struct intel_guc_ct_buffer *ctb = &ct->ctbs.recv;
 	struct guc_ct_buffer_desc *desc = ctb->desc;
 	u32 head = desc->head;
 	u32 tail = desc->tail;
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
index 4009e2dd0de4..fc9486779e87 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_ct.h
@@ -47,8 +47,11 @@ struct intel_guc_ct {
 	struct i915_vma *vma;
 	bool enabled;
 
-	/* buffers for sending(0) and receiving(1) commands */
-	struct intel_guc_ct_buffer ctbs[2];
+	/* buffers for sending and receiving commands */
+	struct {
+		struct intel_guc_ct_buffer send;
+		struct intel_guc_ct_buffer recv;
+	} ctbs;
 
 	struct {
 		u32 last_fence; /* last fence used to send request */
-- 
2.28.0