drm/msm/adreno: Disable IFPC when sysprof is active

Moving to IFPC state clears the 'Perfcounter Select' register setup
by the userspace. So, lets block the IFPC when sysprof is active by
using the perfcounter oob signal to the GMU.

Signed-off-by: Akhil P Oommen <[e-mail]>
Patchwork: https://patchwork.freedesktop.org/patch/673380/
Signed-off-by: Rob Clark <[e-mail]>

drivers/gpu/drm/msm/adreno/a6xx_gmu.c

···
 	/* Set the GPU to the current freq */
 	a6xx_gmu_set_initial_freq(gpu, gmu);
 
+	if (refcount_read(&gpu->sysprof_active) > 1) {
+		ret = a6xx_gmu_set_oob(gmu, GMU_OOB_PERFCOUNTER_SET);
+		if (!ret)
+			set_bit(GMU_STATUS_OOB_PERF_SET, &gmu->status);
+	}
 out:
 	/* On failure, shut down the GMU to leave it in a good state */
 	if (ret) {
···
 
 		a6xx_gmu_clear_oob(&a6xx_gpu->gmu, GMU_OOB_GPU_SET);
 	}
+
+	if (test_and_clear_bit(GMU_STATUS_OOB_PERF_SET, &gmu->status))
+		a6xx_gmu_clear_oob(gmu, GMU_OOB_PERFCOUNTER_SET);
 
 	ret = a6xx_gmu_wait_for_idle(gmu);
 
···
 	}
 
 	return irq;
+}
+
+void a6xx_gmu_sysprof_setup(struct msm_gpu *gpu)
+{
+	struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
+	struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
+	struct a6xx_gmu *gmu = &a6xx_gpu->gmu;
+	unsigned int sysprof_active;
+
+	/* Nothing to do if GPU is suspended. We will handle this during GMU resume */
+	if (!pm_runtime_get_if_active(&gpu->pdev->dev))
+		return;
+
+	mutex_lock(&gmu->lock);
+
+	sysprof_active = refcount_read(&gpu->sysprof_active);
+
+	/*
+	 * 'Perfcounter select' register values are lost during IFPC collapse. To avoid that,
+	 * use the currently unused perfcounter oob vote to block IFPC when sysprof is active
+	 */
+	if ((sysprof_active > 1) && !test_and_set_bit(GMU_STATUS_OOB_PERF_SET, &gmu->status))
+		a6xx_gmu_set_oob(gmu, GMU_OOB_PERFCOUNTER_SET);
+	else if ((sysprof_active == 1) && test_and_clear_bit(GMU_STATUS_OOB_PERF_SET, &gmu->status))
+		a6xx_gmu_clear_oob(gmu, GMU_OOB_PERFCOUNTER_SET);
+
+	mutex_unlock(&gmu->lock);
+
+	pm_runtime_put(&gpu->pdev->dev);
 }
 
 void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu)

drivers/gpu/drm/msm/adreno/a6xx_gmu.h

···
 #define GMU_STATUS_FW_START	0
 /* To track if PDC sleep seq was done */
 #define GMU_STATUS_PDC_SLEEP	1
+/* To track Perfcounter OOB set status */
+#define GMU_STATUS_OOB_PERF_SET 2
 	unsigned long status;
 };
 

drivers/gpu/drm/msm/adreno/a6xx_gpu.c

···
 		.create_private_vm = a6xx_create_private_vm,
 		.get_rptr = a6xx_get_rptr,
 		.progress = a6xx_progress,
+		.sysprof_setup = a6xx_gmu_sysprof_setup,
 	},
 	.get_timestamp = a6xx_gmu_get_timestamp,
 };
···
 		.create_private_vm = a6xx_create_private_vm,
 		.get_rptr = a6xx_get_rptr,
 		.progress = a6xx_progress,
+		.sysprof_setup = a6xx_gmu_sysprof_setup,
 	},
 	.get_timestamp = a6xx_gmu_get_timestamp,
 };

drivers/gpu/drm/msm/adreno/a6xx_gpu.h

···
 int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node);
 int a6xx_gmu_wrapper_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node);
 void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu);
+void a6xx_gmu_sysprof_setup(struct msm_gpu *gpu);
 
 void a6xx_preempt_init(struct msm_gpu *gpu);
 void a6xx_preempt_hw_init(struct msm_gpu *gpu);

drivers/gpu/drm/msm/msm_gpu.h

···
 	 * for cmdstream that is buffered in this FIFO upstream of the CP fw.
 	 */
 	bool (*progress)(struct msm_gpu *gpu, struct msm_ringbuffer *ring);
+	void (*sysprof_setup)(struct msm_gpu *gpu);
 };
 
 /* Additional state for iommu faults: */

drivers/gpu/drm/msm/msm_submitqueue.c

···
 		break;
 	}
 
+	/* Some gpu families require additional setup for sysprof */
+	if (gpu->funcs->sysprof_setup)
+		gpu->funcs->sysprof_setup(gpu);
+
 	ctx->sysprof = sysprof;
 
 	return 0;