drm/msm: Support multiple ringbuffers

Add the infrastructure to support the idea of multiple ringbuffers.
Assign each ringbuffer an id and use that as an index for the various
ring specific operations.

The biggest delta is to support legacy fences. Each fence gets its own
sequence number but the legacy functions expect to use a unique integer.
To handle this we return a unique identifier for each submission but
map it to a specific ring/sequence under the covers. Newer users use
a dma_fence pointer anyway so they don't care about the actual sequence
ID or ring.

The actual mechanics for multiple ringbuffers are very target specific
so this code just allows for the possibility but still only defines
one ringbuffer for each target family.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

1 files changed, 18 insertions, 24 deletions

diff --git a/drivers/gpu/drm/msm/msm_gpu.h b/drivers/gpu/drm/msm/msm_gpu.h
index 8ddda059de34..1be0317bb2c0 100644
--- a/drivers/gpu/drm/msm/msm_gpu.h
+++ b/drivers/gpu/drm/msm/msm_gpu.h
@@ -33,7 +33,7 @@ struct msm_gpu_config {
 	const char *irqname;
 	uint64_t va_start;
 	uint64_t va_end;
-	unsigned int ringsz;
+	unsigned int nr_rings;
 };
 
 /* So far, with hardware that I've seen to date, we can have:
@@ -57,8 +57,9 @@ struct msm_gpu_funcs {
 	int (*pm_resume)(struct msm_gpu *gpu);
 	void (*submit)(struct msm_gpu *gpu, struct msm_gem_submit *submit,
 			struct msm_file_private *ctx);
-	void (*flush)(struct msm_gpu *gpu);
+	void (*flush)(struct msm_gpu *gpu, struct msm_ringbuffer *ring);
 	irqreturn_t (*irq)(struct msm_gpu *irq);
+	struct msm_ringbuffer *(*active_ring)(struct msm_gpu *gpu);
 	void (*recover)(struct msm_gpu *gpu);
 	void (*destroy)(struct msm_gpu *gpu);
 #ifdef CONFIG_DEBUG_FS
@@ -67,14 +68,6 @@ struct msm_gpu_funcs {
 #endif
 };
 
-#define rbmemptr(gpu, member)  \
-	((gpu)->memptrs_iova + offsetof(struct msm_rbmemptrs, member))
-
-struct msm_rbmemptrs {
-	volatile uint32_t rptr;
-	volatile uint32_t fence;
-};
-
 struct msm_gpu {
 	const char *name;
 	struct drm_device *dev;
@@ -93,16 +86,12 @@ struct msm_gpu {
 	const struct msm_gpu_perfcntr *perfcntrs;
 	uint32_t num_perfcntrs;
 
-	/* ringbuffer: */
-	struct msm_ringbuffer *rb;
-	uint64_t rb_iova;
+	struct msm_ringbuffer *rb[MSM_GPU_MAX_RINGS];
+	int nr_rings;
 
 	/* list of GEM active objects: */
 	struct list_head active_list;
 
-	/* fencing: */
-	struct msm_fence_context *fctx;
-
 	/* does gpu need hw_init? */
 	bool needs_hw_init;
 
@@ -133,21 +122,26 @@ struct msm_gpu {
 #define DRM_MSM_HANGCHECK_PERIOD 500 /* in ms */
 #define DRM_MSM_HANGCHECK_JIFFIES msecs_to_jiffies(DRM_MSM_HANGCHECK_PERIOD)
 	struct timer_list hangcheck_timer;
-	uint32_t hangcheck_fence;
 	struct work_struct recover_work;
 
-	struct list_head submit_list;
-
-	struct msm_rbmemptrs *memptrs;
 	struct drm_gem_object *memptrs_bo;
-	uint64_t memptrs_iova;
-
-
 };
 
+/* It turns out that all targets use the same ringbuffer size */
+#define MSM_GPU_RINGBUFFER_SZ SZ_32K
+
 static inline bool msm_gpu_active(struct msm_gpu *gpu)
 {
-	return gpu->fctx->last_fence > gpu->memptrs->fence;
+	int i;
+
+	for (i = 0; i < gpu->nr_rings; i++) {
+		struct msm_ringbuffer *ring = gpu->rb[i];
+
+		if (ring->seqno > ring->memptrs->fence)
+			return true;
+	}
+
+	return false;
 }
 
 /* Perf-Counters: