disp: msm: fix vram allocation when IOMMU is not present

Allocate DSI/LUTDMA buffers from VRAM when IOMMU is not
available. Add checks in msm_gem to avoid few operations
when aspace is not available due to no IOMMU. Parse the
VRAM size from device tree, when available.

Change-Id: Iedf5749b71c2e772ac5434048520a34705c54b45
Signed-off-by: Veera Sundaram Sankaran <[email protected]>

msm/dsi/dsi_display.c

@@ -495,17 +495,23 @@ static int dsi_host_alloc_cmd_tx_buffer(struct dsi_display *display)
 
 	display->aspace = msm_gem_smmu_address_space_get(
 			display->drm_dev, MSM_SMMU_DOMAIN_UNSECURE);
-	if (!display->aspace) {
-		DSI_ERR("failed to get aspace\n");
-		rc = -EINVAL;
-		goto free_gem;
-	}
-	/* register to aspace */
-	rc = msm_gem_address_space_register_cb(display->aspace,
-			dsi_display_aspace_cb_locked, (void *)display);
-	if (rc) {
-		DSI_ERR("failed to register callback %d\n", rc);
+
+	if (PTR_ERR(display->aspace) == -ENODEV) {
+		display->aspace = NULL;
+		DSI_DEBUG("IOMMU not present, relying on VRAM\n");
+	} else if (IS_ERR_OR_NULL(display->aspace)) {
+		rc = PTR_ERR(display->aspace);
+		display->aspace = NULL;
+		DSI_ERR("failed to get aspace %d\n", rc);
 		goto free_gem;
+	} else if (display->aspace) {
+		/* register to aspace */
+		rc = msm_gem_address_space_register_cb(display->aspace,
+				dsi_display_aspace_cb_locked, (void *)display);
+		if (rc) {
+			DSI_ERR("failed to register callback %d\n", rc);
+			goto free_gem;
+		}
 	}
 
 	rc = msm_gem_get_iova(display->tx_cmd_buf, display->aspace,

msm/msm_drv.c

@@ -522,8 +522,13 @@ static int msm_init_vram(struct drm_device *dev)
 		 * mach-msm:
 		 */
 	} else if (!iommu_present(&platform_bus_type)) {
-		DRM_INFO("using %s VRAM carveout\n", vram);
-		size = memparse(vram, NULL);
+		u32 vram_size;
+
+		ret = of_property_read_u32(dev->dev->of_node,
+					"qcom,vram-size", &vram_size);
+		size = (ret < 0) ? memparse(vram, NULL) : vram_size;
+		DRM_INFO("using 0x%x VRAM carveout\n", size);
+		ret = 0;
 	}
 
 	if (size) {
@@ -1894,21 +1899,26 @@ msm_gem_smmu_address_space_get(struct drm_device *dev,
 	struct msm_drm_private *priv = NULL;
 	struct msm_kms *kms;
 	const struct msm_kms_funcs *funcs;
+	struct msm_gem_address_space *aspace;
+
+	if (!iommu_present(&platform_bus_type))
+		return ERR_PTR(-ENODEV);
 
 	if ((!dev) || (!dev->dev_private))
-		return NULL;
+		return ERR_PTR(-EINVAL);
 
 	priv = dev->dev_private;
 	kms = priv->kms;
 	if (!kms)
-		return NULL;
+		return ERR_PTR(-EINVAL);
 
 	funcs = kms->funcs;
 
 	if ((!funcs) || (!funcs->get_address_space))
-		return NULL;
+		return ERR_PTR(-EINVAL);
 
-	return funcs->get_address_space(priv->kms, domain);
+	aspace = funcs->get_address_space(priv->kms, domain);
+	return aspace ? aspace : ERR_PTR(-EINVAL);
 }
 
 int msm_get_mixer_count(struct msm_drm_private *priv,

msm/msm_gem.c

@@ -109,22 +109,23 @@ static struct page **get_pages(struct drm_gem_object *obj)
 			return ptr;
 		}
 
-		/* For non-cached buffers, ensure the new pages are clean
-		 * because display controller, GPU, etc. are not coherent:
+		if (msm_obj->vram_node) {
+			goto end;
+		/*
+		 * For non-cached buffers, ensure the new pages are clean
+		 * because display controller, GPU, etc. are not coherent
 		 */
-		if (msm_obj->flags & (MSM_BO_WC|MSM_BO_UNCACHED)) {
+		} else if (msm_obj->flags & (MSM_BO_WC|MSM_BO_UNCACHED)) {
 			aspace_dev = msm_gem_get_aspace_device(msm_obj->aspace);
 			if (aspace_dev)
 				dma_map_sg(aspace_dev, msm_obj->sgt->sgl,
-						msm_obj->sgt->nents,
-						DMA_BIDIRECTIONAL);
+					msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
 			else
-				dev_err(dev->dev,
-					"failed to get aspace_device\n");
-
+				DRM_ERROR("failed to get aspace_device\n");
 		}
 	}
 
+end:
 	return msm_obj->pages;
 }
 
@@ -191,6 +192,8 @@ void msm_gem_sync(struct drm_gem_object *obj)
 
 	msm_obj = to_msm_bo(obj);
 
+	if (msm_obj->vram_node)
+		return;
 	/*
 	 * dma_sync_sg_for_device synchronises a single contiguous or
 	 * scatter/gather mapping for the CPU and device.
@@ -200,8 +203,7 @@ void msm_gem_sync(struct drm_gem_object *obj)
 		dma_sync_sg_for_device(aspace_dev, msm_obj->sgt->sgl,
 				msm_obj->sgt->nents, DMA_BIDIRECTIONAL);
 	else
-		dev_err(obj->dev->dev,
-			"failed to get aspace_device\n");
+		DRM_ERROR("failed to get aspace_device\n");
 }
 
 

msm/sde/sde_color_processing.c

@@ -3474,7 +3474,13 @@ static void _sde_cp_crtc_set_ltm_buffer(struct sde_crtc *sde_crtc, void *cfg)
 		sde_crtc->ltm_buffers[i]->aspace =
 			msm_gem_smmu_address_space_get(crtc->dev,
 			MSM_SMMU_DOMAIN_UNSECURE);
-		if (!sde_crtc->ltm_buffers[i]->aspace) {
+
+		if (PTR_ERR(sde_crtc->ltm_buffers[i]->aspace) == -ENODEV) {
+			sde_crtc->ltm_buffers[i]->aspace = NULL;
+			DRM_DEBUG("IOMMU not present, relying on VRAM\n");
+		} else if (IS_ERR_OR_NULL(sde_crtc->ltm_buffers[i]->aspace)) {
+			ret = PTR_ERR(sde_crtc->ltm_buffers[i]->aspace);
+			sde_crtc->ltm_buffers[i]->aspace = NULL;
 			DRM_ERROR("failed to get aspace\n");
 			goto exit;
 		}

msm/sde/sde_hw_reg_dma_v1.c

@@ -1015,19 +1015,24 @@ static struct sde_reg_dma_buffer *alloc_reg_dma_buf_v1(u32 size)
 
 	aspace = msm_gem_smmu_address_space_get(reg_dma->drm_dev,
 			MSM_SMMU_DOMAIN_UNSECURE);
-	if (!aspace) {
-		DRM_ERROR("failed to get aspace\n");
-		rc = -EINVAL;
-		goto free_gem;
-	}
 
-	/* register to aspace */
-	rc = msm_gem_address_space_register_cb(aspace,
-			sde_reg_dma_aspace_cb_locked,
-			(void *)dma_buf);
-	if (rc) {
-		DRM_ERROR("failed to register callback %d", rc);
+	if (PTR_ERR(aspace) == -ENODEV) {
+		aspace = NULL;
+		DRM_DEBUG("IOMMU not present, relying on VRAM\n");
+	} else if (IS_ERR_OR_NULL(aspace)) {
+		rc = PTR_ERR(aspace);
+		aspace = NULL;
+		DRM_ERROR("failed to get aspace %d", rc);
 		goto free_gem;
+	} else if (aspace) {
+		/* register to aspace */
+		rc = msm_gem_address_space_register_cb(aspace,
+				sde_reg_dma_aspace_cb_locked,
+				(void *)dma_buf);
+		if (rc) {
+			DRM_ERROR("failed to register callback %d", rc);
+			goto free_gem;
+		}
 	}
 
 	dma_buf->aspace = aspace;