[PATCH 1/5] drm/amdgpu: Expand kernel-doc in amdgpu_ring

[Rodrigo Siqueira]

Expand the kernel-doc about amdgpu_ring and add some tiny improvements.

Cc: Alex Deucher <alexander.deucher at amd.com>
Cc: Christian König <christian.koenig at amd.com>
Cc: Timur Kristóf <timur.kristof at gmail.com>
Signed-off-by: Rodrigo Siqueira <siqueira at igalia.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c | 15 ++++++++++++---
 drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h |  2 ++
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
index 6379bb25bf5c..78fd324c84e9 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.c
@@ -75,8 +75,16 @@ unsigned int amdgpu_ring_max_ibs(enum amdgpu_ring_type type)
  * @ring: amdgpu_ring structure holding ring information
  * @ndw: number of dwords to allocate in the ring buffer
  *
- * Allocate @ndw dwords in the ring buffer (all asics).
- * Returns 0 on success, error on failure.
+ * Allocate @ndw dwords in the ring buffer (it works in all ASICs). When
+ * inspecting the code, you may encounter places where this function is called
+ * amdgpu_ring_alloc(ring, X + Y + Z) where X, Y, and Z are integer numbers.
+ * This is a way to show how many dwords operations will be inserted in the
+ * ring. For example, if gfx_v9_0_wait_reg_mem(), amdgpu_ring_emit_reg_wait(),
+ * amdgpu_ring_emit_wreg(), and amdgpu_ring_emit_fence() will be called, before
+ * that you will see amdgpu_ring_alloc(ring, 7 + 7 + 5 + 8).
+ *
+ * Returns:
+ * 0 on success, error on failure.
  */
 int amdgpu_ring_alloc(struct amdgpu_ring *ring, unsigned int ndw)
 {
@@ -122,7 +130,8 @@ static void amdgpu_ring_alloc_reemit(struct amdgpu_ring *ring, unsigned int ndw)
 		ring->funcs->begin_use(ring);
 }
 
-/** amdgpu_ring_insert_nop - insert NOP packets
+/**
+ * amdgpu_ring_insert_nop - insert NOP packets
  *
  * @ring: amdgpu_ring structure holding ring information
  * @count: the number of NOP packets to insert
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
index 7670f5d82b9e..d27dbb3c109f 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
@@ -62,6 +62,8 @@ enum amdgpu_ring_priority_level {
 #define AMDGPU_FENCE_FLAG_64BIT         (1 << 0)
 #define AMDGPU_FENCE_FLAG_INT           (1 << 1)
 #define AMDGPU_FENCE_FLAG_TC_WB_ONLY    (1 << 2)
+
+/* Ensure the execution in case of preemption or reset */
 #define AMDGPU_FENCE_FLAG_EXEC          (1 << 3)
 
 #define to_amdgpu_ring(s) container_of((s), struct amdgpu_ring, sched)
-- 
2.47.2