[PATCH v2] drm/rockchip: support non-iommu buffer path

Mark Yao
2016-04-20T02:53:33Z

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, the would help the debug.

Signed-off-by: Mark Yao <mark.yao@rock-chips.com>
---
Changes in v2
Advised by Heiko Stuebner
- use more suitable message print.

drivers/gpu/drm/rockchip/rockchip_drm_drv.c | 64 +++++++++++++++++++--------
1 file changed, 46 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_drv.c b/drivers/gpu/drm/rockchip/rockchip_drm_drv.c
index f556a8f..00aa175 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);
}

@@ -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);
@@ -226,9 +237,11 @@ 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(dev->archdata.mapping);
+ if (is_support_iommu)
+ arm_iommu_release_mapping(dev->archdata.mapping);
err_config_cleanup:
drm_mode_config_cleanup(drm_dev);
drm_dev->dev_private = NULL;
@@ -243,8 +256,10 @@ 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);
- arm_iommu_release_mapping(dev->archdata.mapping);
+ if (is_support_iommu) {
+ arm_iommu_detach_device(dev);
+ arm_iommu_release_mapping(dev->archdata.mapping);
+ }
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);
}
--
1.7.9.5