drm/rockchip: support non-iommu buffer path

Some rockchip vop not support iommu, need use non-iommu
buffer for it. And if we get iommu issues, we can compare
the issues with non-iommu path, that would help the debug.

Signed-off-by: Mark Yao <mark.yao@rock-chips.com>

1 files changed, 47 insertions, 19 deletions

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
index 1e2d88bdd9f7..399adf3c4224 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
@@ -36,6 +36,8 @@
 #define DRIVER_MAJOR    1
 #define DRIVER_MINOR    0
 
+static bool is_support_iommu = true;
+
 /*
  * Attach a (component) device to the shared drm dma mapping from master drm
  * device.  This is used by the VOPs to map GEM buffers to a common DMA
@@ -47,6 +49,9 @@ int rockchip_drm_dma_attach_device(struct drm_device *drm_dev,
         struct dma_iommu_mapping *mapping = drm_dev->dev->archdata.mapping;
         int ret;
 
+        if (!is_support_iommu)
+                return 0;
+
         ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
         if (ret)
                 return ret;
@@ -59,6 +64,9 @@ int rockchip_drm_dma_attach_device(struct drm_device *drm_dev,
 void rockchip_drm_dma_detach_device(struct drm_device *drm_dev,
                                     struct device *dev)
 {
+        if (!is_support_iommu)
+                return;
+
         arm_iommu_detach_device(dev);
 }
 
@@ -127,7 +135,7 @@ static void rockchip_drm_crtc_disable_vblank(struct drm_device *dev,
 static int rockchip_drm_load(struct drm_device *drm_dev, unsigned long flags)
 {
         struct rockchip_drm_private *private;
-        struct dma_iommu_mapping *mapping;
+        struct dma_iommu_mapping *mapping = NULL;
         struct device *dev = drm_dev->dev;
         struct drm_connector *connector;
         int ret;
@@ -152,23 +160,26 @@ static int rockchip_drm_load(struct drm_device *drm_dev, unsigned long flags)
                 goto err_config_cleanup;
         }
 
-        /* TODO(djkurtz): fetch the mapping start/size from somewhere */
-        mapping = arm_iommu_create_mapping(&platform_bus_type, 0x00000000,
-                                           SZ_2G);
-        if (IS_ERR(mapping)) {
-                ret = PTR_ERR(mapping);
-                goto err_config_cleanup;
-        }
+        if (is_support_iommu) {
+                /* TODO(djkurtz): fetch the mapping start/size from somewhere */
+                mapping = arm_iommu_create_mapping(&platform_bus_type,
+                                                   0x00000000,
+                                                   SZ_2G);
+                if (IS_ERR(mapping)) {
+                        ret = PTR_ERR(mapping);
+                        goto err_config_cleanup;
+                }
 
-        ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
-        if (ret)
-                goto err_release_mapping;
+                ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
+                if (ret)
+                        goto err_release_mapping;
 
-        dma_set_max_seg_size(dev, DMA_BIT_MASK(32));
+                dma_set_max_seg_size(dev, DMA_BIT_MASK(32));
 
-        ret = arm_iommu_attach_device(dev, mapping);
-        if (ret)
-                goto err_release_mapping;
+                ret = arm_iommu_attach_device(dev, mapping);
+                if (ret)
+                        goto err_release_mapping;
+        }
 
         /* Try to bind all sub drivers. */
         ret = component_bind_all(dev, drm_dev);
@@ -218,7 +229,8 @@ static int rockchip_drm_load(struct drm_device *drm_dev, unsigned long flags)
         if (ret)
                 goto err_vblank_cleanup;
 
-        arm_iommu_release_mapping(mapping);
+        if (is_support_iommu)
+                arm_iommu_release_mapping(mapping);
         return 0;
 err_vblank_cleanup:
         drm_vblank_cleanup(drm_dev);
@@ -227,9 +239,11 @@ err_kms_helper_poll_fini:
 err_unbind:
         component_unbind_all(dev, drm_dev);
 err_detach_device:
-        arm_iommu_detach_device(dev);
+        if (is_support_iommu)
+                arm_iommu_detach_device(dev);
 err_release_mapping:
-        arm_iommu_release_mapping(mapping);
+        if (is_support_iommu)
+                arm_iommu_release_mapping(mapping);
 err_config_cleanup:
         drm_mode_config_cleanup(drm_dev);
         drm_dev->dev_private = NULL;
@@ -244,7 +258,8 @@ static int rockchip_drm_unload(struct drm_device *drm_dev)
         drm_vblank_cleanup(drm_dev);
         drm_kms_helper_poll_fini(drm_dev);
         component_unbind_all(dev, drm_dev);
-        arm_iommu_detach_device(dev);
+        if (is_support_iommu)
+                arm_iommu_detach_device(dev);
         drm_mode_config_cleanup(drm_dev);
         drm_dev->dev_private = NULL;
 
@@ -488,6 +503,8 @@ static int rockchip_drm_platform_probe(struct platform_device *pdev)
          * works as expected.
          */
         for (i = 0;; i++) {
+                struct device_node *iommu;
+
                 port = of_parse_phandle(np, "ports", i);
                 if (!port)
                         break;
@@ -497,6 +514,17 @@ static int rockchip_drm_platform_probe(struct platform_device *pdev)
                         continue;
                 }
 
+                iommu = of_parse_phandle(port->parent, "iommus", 0);
+                if (!iommu || !of_device_is_available(iommu->parent)) {
+                        dev_dbg(dev, "no iommu attached for %s, using non-iommu buffers\n",
+                                port->parent->full_name);
+                        /*
+                         * if there is a crtc not support iommu, force set all
+                         * crtc use non-iommu buffer.
+                         */
+                        is_support_iommu = false;
+                }
+
                 component_match_add(dev, &match, compare_of, port->parent);
                 of_node_put(port);
         }