diff mbox series

[v8,08/12] drm/msm/a6xx: Use posamble to reset counters on preemption

Message ID 20241003-preemption-a750-t-v8-8-5c6cb9f256e0@gmail.com
State Accepted
Commit 50117cad0c50410cff0d43a1141a562b1347e7c5
Headers show
Series Preemption support for A7XX | expand

Commit Message

Antonino Maniscalco Oct. 3, 2024, 4:12 p.m. UTC 
Use the postamble to reset perf counters when switching between rings,
except when sysprof is enabled, analogously to how they are reset
between submissions when switching pagetables.

Reviewed-by: Akhil P Oommen <quic_akhilpo@quicinc.com>
Tested-by: Rob Clark <robdclark@gmail.com>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8650-QRD
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8550-QRD
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8450-HDK
Signed-off-by: Antonino Maniscalco <antomani103@gmail.com>
---
 drivers/gpu/drm/msm/adreno/a6xx_gpu.c     | 12 +++++++
 drivers/gpu/drm/msm/adreno/a6xx_gpu.h     |  6 ++++
 drivers/gpu/drm/msm/adreno/a6xx_preempt.c | 58 +++++++++++++++++++++++++++++++
 drivers/gpu/drm/msm/adreno/adreno_gpu.h   |  7 ++--
 4 files changed, 81 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index b4cd562f1dd8660c77430e1aeac7e4b7af32bfc7..9b486ec08f77933c3666549a16d915aa2d2188b0 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -280,6 +280,8 @@  static void a6xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
 static void a6xx_emit_set_pseudo_reg(struct msm_ringbuffer *ring,
 		struct a6xx_gpu *a6xx_gpu, struct msm_gpu_submitqueue *queue)
 {
+	u64 preempt_postamble;
+
 	OUT_PKT7(ring, CP_SET_PSEUDO_REG, 12);
 
 	OUT_RING(ring, SMMU_INFO);
@@ -303,6 +305,16 @@  static void a6xx_emit_set_pseudo_reg(struct msm_ringbuffer *ring,
 	/* seems OK to set to 0 to disable it */
 	OUT_RING(ring, 0);
 	OUT_RING(ring, 0);
+
+	/* Emit postamble to clear perfcounters */
+	preempt_postamble = a6xx_gpu->preempt_postamble_iova;
+
+	OUT_PKT7(ring, CP_SET_AMBLE, 3);
+	OUT_RING(ring, lower_32_bits(preempt_postamble));
+	OUT_RING(ring, upper_32_bits(preempt_postamble));
+	OUT_RING(ring, CP_SET_AMBLE_2_DWORDS(
+				 a6xx_gpu->preempt_postamble_len) |
+			 CP_SET_AMBLE_2_TYPE(KMD_AMBLE_TYPE));
 }
 
 static void a7xx_submit(struct msm_gpu *gpu, struct msm_gem_submit *submit)
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.h b/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
index 070bce058d3ff92aa7452b697763a16ab7e2faee..a7fde9a27481f4f6d4efdde98a12ae4b62332f47 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.h
@@ -69,6 +69,12 @@  struct a6xx_gpu {
 	bool uses_gmem;
 	bool skip_save_restore;
 
+	struct drm_gem_object *preempt_postamble_bo;
+	void *preempt_postamble_ptr;
+	uint64_t preempt_postamble_iova;
+	uint64_t preempt_postamble_len;
+	bool postamble_enabled;
+
 	struct a6xx_gmu gmu;
 
 	struct drm_gem_object *shadow_bo;
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_preempt.c b/drivers/gpu/drm/msm/adreno/a6xx_preempt.c
index fd2a90360740591d45758f7311ec5cdda1855b20..21e333cb6342d33425eb96f97bcc853e9b041b36 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_preempt.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_preempt.c
@@ -97,6 +97,43 @@  static void a6xx_preempt_timer(struct timer_list *t)
 	kthread_queue_work(gpu->worker, &gpu->recover_work);
 }
 
+static void preempt_prepare_postamble(struct a6xx_gpu *a6xx_gpu)
+{
+	u32 *postamble = a6xx_gpu->preempt_postamble_ptr;
+	u32 count = 0;
+
+	postamble[count++] = PKT7(CP_REG_RMW, 3);
+	postamble[count++] = REG_A6XX_RBBM_PERFCTR_SRAM_INIT_CMD;
+	postamble[count++] = 0;
+	postamble[count++] = 1;
+
+	postamble[count++] = PKT7(CP_WAIT_REG_MEM, 6);
+	postamble[count++] = CP_WAIT_REG_MEM_0_FUNCTION(WRITE_EQ);
+	postamble[count++] = CP_WAIT_REG_MEM_1_POLL_ADDR_LO(
+				REG_A6XX_RBBM_PERFCTR_SRAM_INIT_STATUS);
+	postamble[count++] = CP_WAIT_REG_MEM_2_POLL_ADDR_HI(0);
+	postamble[count++] = CP_WAIT_REG_MEM_3_REF(0x1);
+	postamble[count++] = CP_WAIT_REG_MEM_4_MASK(0x1);
+	postamble[count++] = CP_WAIT_REG_MEM_5_DELAY_LOOP_CYCLES(0);
+
+	a6xx_gpu->preempt_postamble_len = count;
+
+	a6xx_gpu->postamble_enabled = true;
+}
+
+static void preempt_disable_postamble(struct a6xx_gpu *a6xx_gpu)
+{
+	u32 *postamble = a6xx_gpu->preempt_postamble_ptr;
+
+	/*
+	 * Disable the postamble by replacing the first packet header with a NOP
+	 * that covers the whole buffer.
+	 */
+	*postamble = PKT7(CP_NOP, (a6xx_gpu->preempt_postamble_len - 1));
+
+	a6xx_gpu->postamble_enabled = false;
+}
+
 void a6xx_preempt_irq(struct msm_gpu *gpu)
 {
 	uint32_t status;
@@ -187,6 +224,7 @@  void a6xx_preempt_trigger(struct msm_gpu *gpu)
 	unsigned long flags;
 	struct msm_ringbuffer *ring;
 	unsigned int cntl;
+	bool sysprof;
 
 	if (gpu->nr_rings == 1)
 		return;
@@ -271,6 +309,15 @@  void a6xx_preempt_trigger(struct msm_gpu *gpu)
 	/* Start a timer to catch a stuck preemption */
 	mod_timer(&a6xx_gpu->preempt_timer, jiffies + msecs_to_jiffies(10000));
 
+	/* Enable or disable postamble as needed */
+	sysprof = refcount_read(&a6xx_gpu->base.base.sysprof_active) > 1;
+
+	if (!sysprof && !a6xx_gpu->postamble_enabled)
+		preempt_prepare_postamble(a6xx_gpu);
+
+	if (sysprof && a6xx_gpu->postamble_enabled)
+		preempt_disable_postamble(a6xx_gpu);
+
 	/* Set the preemption state to triggered */
 	set_preempt_state(a6xx_gpu, PREEMPT_TRIGGERED);
 
@@ -375,6 +422,17 @@  void a6xx_preempt_init(struct msm_gpu *gpu)
 	a6xx_gpu->uses_gmem = 1;
 	a6xx_gpu->skip_save_restore = 1;
 
+	a6xx_gpu->preempt_postamble_ptr  = msm_gem_kernel_new(gpu->dev,
+			PAGE_SIZE,
+			MSM_BO_WC | MSM_BO_MAP_PRIV | MSM_BO_GPU_READONLY,
+			gpu->aspace, &a6xx_gpu->preempt_postamble_bo,
+			&a6xx_gpu->preempt_postamble_iova);
+
+	preempt_prepare_postamble(a6xx_gpu);
+
+	if (IS_ERR(a6xx_gpu->preempt_postamble_ptr))
+		goto fail;
+
 	timer_setup(&a6xx_gpu->preempt_timer, a6xx_preempt_timer, 0);
 
 	return;
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.h b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
index 58c63d0fbbff9818393fc62ee3cf2703365bec23..2d8eef6c668b0da246edceba0c5d92041ea9a35b 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.h
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
@@ -623,12 +623,15 @@  OUT_PKT4(struct msm_ringbuffer *ring, uint16_t regindx, uint16_t cnt)
 	OUT_RING(ring, PKT4(regindx, cnt));
 }
 
+#define PKT7(opcode, cnt) \
+	(CP_TYPE7_PKT | (cnt << 0) | (PM4_PARITY(cnt) << 15) | \
+		((opcode & 0x7F) << 16) | (PM4_PARITY(opcode) << 23))
+
 static inline void
 OUT_PKT7(struct msm_ringbuffer *ring, uint8_t opcode, uint16_t cnt)
 {
 	adreno_wait_ring(ring, cnt + 1);
-	OUT_RING(ring, CP_TYPE7_PKT | (cnt << 0) | (PM4_PARITY(cnt) << 15) |
-		((opcode & 0x7F) << 16) | (PM4_PARITY(opcode) << 23));
+	OUT_RING(ring, PKT7(opcode, cnt));
 }
 
 struct msm_gpu *a2xx_gpu_init(struct drm_device *dev);