Hi Andrzej,
On 2018-09-21 10:58, Andrzej Hajda wrote:
> Moving DMA mapping creation to drm_iommu_attach_device allows to avoid
> looping through all components and maintaining DMA device flags.
>
> Signed-off-by: Andrzej Hajda <a.hajda@xxxxxxxxxxx>
> ---
> drivers/gpu/drm/exynos/exynos_drm_drv.c | 50 +++--------------------
> drivers/gpu/drm/exynos/exynos_drm_iommu.c | 13 +++++-
I like simplification, but this one is a bit too invasive. It breaks
Exynos DRM when IOMMU support is disabled (dma_dev won't be set in such
case).
> 2 files changed, 17 insertions(+), 46 deletions(-)
>
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c
> index b599f74692e5..c83437d8a595 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_drv.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c
> @@ -197,8 +197,7 @@ struct exynos_drm_driver_info {
>
> #define DRM_COMPONENT_DRIVER BIT(0) /* supports component framework */
> #define DRM_VIRTUAL_DEVICE BIT(1) /* create virtual platform device */
> -#define DRM_DMA_DEVICE BIT(2) /* can be used for dma allocations */
> -#define DRM_FIMC_DEVICE BIT(3) /* devices shared with V4L2 subsystem */
> +#define DRM_FIMC_DEVICE BIT(2) /* devices shared with V4L2 subsystem */
>
> #define DRV_PTR(drv, cond) (IS_ENABLED(cond) ? &drv : NULL)
>
> @@ -209,16 +208,16 @@ struct exynos_drm_driver_info {
> static struct exynos_drm_driver_info exynos_drm_drivers[] = {
> {
> DRV_PTR(fimd_driver, CONFIG_DRM_EXYNOS_FIMD),
> - DRM_COMPONENT_DRIVER | DRM_DMA_DEVICE
> + DRM_COMPONENT_DRIVER
> }, {
> DRV_PTR(exynos5433_decon_driver, CONFIG_DRM_EXYNOS5433_DECON),
> - DRM_COMPONENT_DRIVER | DRM_DMA_DEVICE
> + DRM_COMPONENT_DRIVER
> }, {
> DRV_PTR(decon_driver, CONFIG_DRM_EXYNOS7_DECON),
> - DRM_COMPONENT_DRIVER | DRM_DMA_DEVICE
> + DRM_COMPONENT_DRIVER
> }, {
> DRV_PTR(mixer_driver, CONFIG_DRM_EXYNOS_MIXER),
> - DRM_COMPONENT_DRIVER | DRM_DMA_DEVICE
> + DRM_COMPONENT_DRIVER
> }, {
> DRV_PTR(mic_driver, CONFIG_DRM_EXYNOS_MIC),
> DRM_COMPONENT_DRIVER
> @@ -289,27 +288,6 @@ static struct component_match *exynos_drm_match_add(struct device *dev)
> return match ?: ERR_PTR(-ENODEV);
> }
>
> -static struct device *exynos_drm_get_dma_device(void)
> -{
> - int i;
> -
> - for (i = 0; i < ARRAY_SIZE(exynos_drm_drivers); ++i) {
> - struct exynos_drm_driver_info *info = &exynos_drm_drivers[i];
> - struct device *dev;
> -
> - if (!info->driver || !(info->flags & DRM_DMA_DEVICE))
> - continue;
> -
> - while ((dev = bus_find_device(&platform_bus_type, NULL,
> - &info->driver->driver,
> - (void *)platform_bus_type.match))) {
> - put_device(dev);
> - return dev;
> - }
> - }
> - return NULL;
> -}
> -
> static int exynos_drm_bind(struct device *dev)
> {
> struct exynos_drm_private *private;
> @@ -334,23 +312,6 @@ static int exynos_drm_bind(struct device *dev)
> dev_set_drvdata(dev, drm);
> drm->dev_private = (void *)private;
>
> - /* the first real CRTC device is used for all dma mapping operations */
> - private->dma_dev = exynos_drm_get_dma_device();
> - if (!private->dma_dev) {
> - DRM_ERROR("no device found for DMA mapping operations.\n");
> - ret = -ENODEV;
> - goto err_free_private;
> - }
> - DRM_INFO("Exynos DRM: using %s device for DMA mapping operations\n",
> - dev_name(private->dma_dev));
> -
> - /* create common IOMMU mapping for all devices attached to Exynos DRM */
> - ret = drm_create_iommu_mapping(drm);
> - if (ret < 0) {
> - DRM_ERROR("failed to create iommu mapping.\n");
> - goto err_free_private;
> - }
> -
> drm_mode_config_init(drm);
>
> exynos_drm_mode_config_init(drm);
> @@ -408,7 +369,6 @@ static int exynos_drm_bind(struct device *dev)
> err_mode_config_cleanup:
> drm_mode_config_cleanup(drm);
> drm_release_iommu_mapping(drm);
> -err_free_private:
> kfree(private);
> err_free_drm:
> drm_dev_put(drm);
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_iommu.c b/drivers/gpu/drm/exynos/exynos_drm_iommu.c
> index 0f373702414e..bb8b800a9fba 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_iommu.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_iommu.c
> @@ -75,7 +75,18 @@ int drm_iommu_attach_device(struct drm_device *drm_dev,
> struct exynos_drm_private *priv = drm_dev->dev_private;
> int ret;
>
> - if (get_dma_ops(priv->dma_dev) != get_dma_ops(subdrv_dev)) {
> + if (!priv->dma_dev) {
> + priv->dma_dev = subdrv_dev;
> + DRM_INFO("Exynos DRM: using %s device for DMA mapping operations\n",
> + dev_name(subdrv_dev));
> + /* create common IOMMU mapping for all Exynos DRM devices */
> + ret = drm_create_iommu_mapping(drm_dev);
> + if (ret < 0) {
> + priv->dma_dev = NULL;
> + DRM_ERROR("failed to create iommu mapping.\n");
> + return -EINVAL;
> + }
> + } else if (get_dma_ops(priv->dma_dev) != get_dma_ops(subdrv_dev)) {
> DRM_ERROR("Device %s lacks support for IOMMU\n",
> dev_name(subdrv_dev));
> return -EINVAL;
Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland
