Re: [PATCH v4 1/5] drm/rockchip: Add basic drm driver
From: Arnd Bergmann <arnd@arndb.de>
Date: 2014-09-22 14:44:32
Also in:
dri-devel, linux-devicetree, lkml
On Monday 22 September 2014 18:48:54 Mark yao wrote:
quoted hunk ↗ jump to hunk
diff --git a/drivers/gpu/drm/rockchip/Kconfig b/drivers/gpu/drm/rockchip/Kconfig new file mode 100644 index 0000000..7146c80 --- /dev/null +++ b/drivers/gpu/drm/rockchip/Kconfig@@ -0,0 +1,19 @@ +config DRM_ROCKCHIP + tristate "DRM Support for Rockchip" + depends on DRM && ROCKCHIP_IOMMU + select ARM_DMA_USE_IOMMU + select IOMMU_API + select DRM_KMS_HELPER + select DRM_KMS_FB_HELPER + select DRM_PANEL + select FB_CFB_FILLRECT + select FB_CFB_COPYAREA + select FB_CFB_IMAGEBLIT + select VT_HW_CONSOLE_BINDING if FRAMEBUFFER_CONSOLE + select VIDEOMODE_HELPERS
Be careful with 'select', at least some of these should be 'depends on'. In particular IOMMU_API and ARM_DMA_USE_IOMMU, but possibly others as well. Just check how the symbols are used normally, if you get this wrong, we can end up with incorrect dependencies or loops.
quoted hunk ↗ jump to hunk
diff --git a/drivers/gpu/drm/rockchip/Makefile b/drivers/gpu/drm/rockchip/Makefile new file mode 100644 index 0000000..6e6d468 --- /dev/null +++ b/drivers/gpu/drm/rockchip/Makefile@@ -0,0 +1,10 @@ +# +# Makefile for the drm device driver. This driver provides support for the +# Direct Rendering Infrastructure (DRI) in XFree86 4.1.0 and higher. + +ccflags-y := -Iinclude/drm -Idrivers/gpu/drm/rockchip
The second one should not be required.
+static int rockchip_drm_load(struct drm_device *drm_dev, unsigned long flags)
+{
+ struct rockchip_drm_private *private;
+ struct dma_iommu_mapping *mapping;
+ struct device *dev = drm_dev->dev;
+ int ret;
+
+ private = devm_kzalloc(drm_dev->dev, sizeof(*private), GFP_KERNEL);
+ if (!private)
+ return -ENOMEM;
+
+ dev_set_drvdata(drm_dev->dev, dev);
+ drm_dev->dev_private = private;
+
+ drm_mode_config_init(drm_dev);
+
+ rockchip_drm_mode_config_init(drm_dev);
+
+ dev->dma_parms = devm_kzalloc(dev, sizeof(*dev->dma_parms),
+ GFP_KERNEL);
+ if (!dev->dma_parms) {
+ ret = -ENOMEM;
+ goto err_config_cleanup;
+ }
+
+ /* TODO(djkurtz): fetch the mapping start/size from somewhere */
+ mapping = arm_iommu_create_mapping(&platform_bus_type, 0x10000000,
+ SZ_1G);
+ if (IS_ERR(mapping)) {
+ ret = PTR_ERR(mapping);
+ goto err_config_cleanup;
+ }
+
+ dma_set_coherent_mask(dev, DMA_BIT_MASK(32));This is the default coherent mask. If you call this function, you should normally check the return value, or call dma_set_mask first, which you apparently don't do here, and in another place in this patch. Arnd