1 files changed, 52 insertions, 2 deletions

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
index ff6aa5dfb2d7..87ef34150d46 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -487,6 +487,47 @@ static int etnaviv_hw_reset(struct etnaviv_gpu *gpu)
 	return 0;
 }
 
+static void etnaviv_gpu_enable_mlcg(struct etnaviv_gpu *gpu)
+{
+	u32 pmc, ppc;
+
+	/* enable clock gating */
+	ppc = gpu_read(gpu, VIVS_PM_POWER_CONTROLS);
+	ppc |= VIVS_PM_POWER_CONTROLS_ENABLE_MODULE_CLOCK_GATING;
+
+	/* Disable stall module clock gating for 4.3.0.1 and 4.3.0.2 revs */
+	if (gpu->identity.revision == 0x4301 ||
+	    gpu->identity.revision == 0x4302)
+		ppc |= VIVS_PM_POWER_CONTROLS_DISABLE_STALL_MODULE_CLOCK_GATING;
+
+	gpu_write(gpu, VIVS_PM_POWER_CONTROLS, ppc);
+
+	pmc = gpu_read(gpu, VIVS_PM_MODULE_CONTROLS);
+
+	/* Disable PA clock gating for GC400+ except for GC420 */
+	if (gpu->identity.model >= chipModel_GC400 &&
+	    gpu->identity.model != chipModel_GC420)
+		pmc |= VIVS_PM_MODULE_CONTROLS_DISABLE_MODULE_CLOCK_GATING_PA;
+
+	/*
+	 * Disable PE clock gating on revs < 5.0.0.0 when HZ is
+	 * present without a bug fix.
+	 */
+	if (gpu->identity.revision < 0x5000 &&
+	    gpu->identity.minor_features0 & chipMinorFeatures0_HZ &&
+	    !(gpu->identity.minor_features1 &
+	      chipMinorFeatures1_DISABLE_PE_GATING))
+		pmc |= VIVS_PM_MODULE_CONTROLS_DISABLE_MODULE_CLOCK_GATING_PE;
+
+	if (gpu->identity.revision < 0x5422)
+		pmc |= BIT(15); /* Unknown bit */
+
+	pmc |= VIVS_PM_MODULE_CONTROLS_DISABLE_MODULE_CLOCK_GATING_RA_HZ;
+	pmc |= VIVS_PM_MODULE_CONTROLS_DISABLE_MODULE_CLOCK_GATING_RA_EZ;
+
+	gpu_write(gpu, VIVS_PM_MODULE_CONTROLS, pmc);
+}
+
 static void etnaviv_gpu_hw_init(struct etnaviv_gpu *gpu)
 {
 	u16 prefetch;
@@ -506,6 +547,9 @@ static void etnaviv_gpu_hw_init(struct etnaviv_gpu *gpu)
 		gpu_write(gpu, VIVS_MC_DEBUG_MEMORY, mc_memory_debug);
 	}
 
+	/* enable module-level clock gating */
+	etnaviv_gpu_enable_mlcg(gpu);
+
 	/*
 	 * Update GPU AXI cache atttribute to "cacheable, no allocate".
 	 * This is necessary to prevent the iMX6 SoC locking up.
@@ -553,8 +597,10 @@ int etnaviv_gpu_init(struct etnaviv_gpu *gpu)
 	bool mmuv2;
 
 	ret = pm_runtime_get_sync(gpu->dev);
-	if (ret < 0)
+	if (ret < 0) {
+		dev_err(gpu->dev, "Failed to enable GPU power domain\n");
 		return ret;
+	}
 
 	etnaviv_hw_identify(gpu);
 
@@ -591,8 +637,10 @@ int etnaviv_gpu_init(struct etnaviv_gpu *gpu)
 	}
 
 	ret = etnaviv_hw_reset(gpu);
-	if (ret)
+	if (ret) {
+		dev_err(gpu->dev, "GPU reset failed\n");
 		goto fail;
+	}
 
 	/* Setup IOMMU.. eventually we will (I think) do this once per context
 	 * and have separate page tables per context.  For now, to keep things
@@ -610,12 +658,14 @@ int etnaviv_gpu_init(struct etnaviv_gpu *gpu)
 	}
 
 	if (!iommu) {
+		dev_err(gpu->dev, "Failed to allocate GPU IOMMU domain\n");
 		ret = -ENOMEM;
 		goto fail;
 	}
 
 	gpu->mmu = etnaviv_iommu_new(gpu, iommu, version);
 	if (!gpu->mmu) {
+		dev_err(gpu->dev, "Failed to instantiate GPU IOMMU\n");
 		iommu_domain_free(iommu);
 		ret = -ENOMEM;
 		goto fail;