[PATCH v4 09/13] iommu/rockchip: Use IOMMU device for dma mapping operations
Robin Murphy
robin.murphy at arm.com
Thu Jan 18 04:35:25 PST 2018
On 18/01/18 11:52, Jeffy Chen wrote:
> Use the first registered IOMMU device for dma mapping operations, and
> drop the domain platform device.
>
> This is similar to exynos iommu driver.
I'd been meaning to look into this myself for the sake of removing the
arch_setup_dma_ops() hack, so I'm glad to see it done :)
Reviewed-by: Robin Murphy <robin.murphy at arm.com>
> Signed-off-by: Jeffy Chen <jeffy.chen at rock-chips.com>
> Reviewed-by: Tomasz Figa <tfiga at chromium.org>
> ---
>
> Changes in v4: None
> Changes in v3: None
> Changes in v2: None
>
> drivers/iommu/rockchip-iommu.c | 85 ++++++++++++------------------------------
> 1 file changed, 24 insertions(+), 61 deletions(-)
>
> diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
> index 9b85a3050449..bdb7c5de6fc2 100644
> --- a/drivers/iommu/rockchip-iommu.c
> +++ b/drivers/iommu/rockchip-iommu.c
> @@ -77,7 +77,6 @@
>
> struct rk_iommu_domain {
> struct list_head iommus;
> - struct platform_device *pdev;
> u32 *dt; /* page directory table */
> dma_addr_t dt_dma;
> spinlock_t iommus_lock; /* lock for iommus list */
> @@ -98,12 +97,14 @@ struct rk_iommu {
> struct iommu_domain *domain; /* domain to which iommu is attached */
> };
>
> +static struct device *dma_dev;
> +
> static inline void rk_table_flush(struct rk_iommu_domain *dom, dma_addr_t dma,
> unsigned int count)
> {
> size_t size = count * sizeof(u32); /* count of u32 entry */
>
> - dma_sync_single_for_device(&dom->pdev->dev, dma, size, DMA_TO_DEVICE);
> + dma_sync_single_for_device(dma_dev, dma, size, DMA_TO_DEVICE);
> }
>
> static struct rk_iommu_domain *to_rk_domain(struct iommu_domain *dom)
> @@ -690,7 +691,6 @@ static void rk_iommu_zap_iova_first_last(struct rk_iommu_domain *rk_domain,
> static u32 *rk_dte_get_page_table(struct rk_iommu_domain *rk_domain,
> dma_addr_t iova)
> {
> - struct device *dev = &rk_domain->pdev->dev;
> u32 *page_table, *dte_addr;
> u32 dte_index, dte;
> phys_addr_t pt_phys;
> @@ -708,9 +708,9 @@ static u32 *rk_dte_get_page_table(struct rk_iommu_domain *rk_domain,
> if (!page_table)
> return ERR_PTR(-ENOMEM);
>
> - pt_dma = dma_map_single(dev, page_table, SPAGE_SIZE, DMA_TO_DEVICE);
> - if (dma_mapping_error(dev, pt_dma)) {
> - dev_err(dev, "DMA mapping error while allocating page table\n");
> + pt_dma = dma_map_single(dma_dev, page_table, SPAGE_SIZE, DMA_TO_DEVICE);
> + if (dma_mapping_error(dma_dev, pt_dma)) {
> + dev_err(dma_dev, "DMA mapping error while allocating page table\n");
> free_page((unsigned long)page_table);
> return ERR_PTR(-ENOMEM);
> }
> @@ -982,29 +982,20 @@ static void rk_iommu_detach_device(struct iommu_domain *domain,
> static struct iommu_domain *rk_iommu_domain_alloc(unsigned type)
> {
> struct rk_iommu_domain *rk_domain;
> - struct platform_device *pdev;
> - struct device *iommu_dev;
>
> if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA)
> return NULL;
>
> - /* Register a pdev per domain, so DMA API can base on this *dev
> - * even some virtual master doesn't have an iommu slave
> - */
> - pdev = platform_device_register_simple("rk_iommu_domain",
> - PLATFORM_DEVID_AUTO, NULL, 0);
> - if (IS_ERR(pdev))
> + if (!dma_dev)
> return NULL;
>
> - rk_domain = devm_kzalloc(&pdev->dev, sizeof(*rk_domain), GFP_KERNEL);
> + rk_domain = devm_kzalloc(dma_dev, sizeof(*rk_domain), GFP_KERNEL);
> if (!rk_domain)
> - goto err_unreg_pdev;
> -
> - rk_domain->pdev = pdev;
> + return NULL;
>
> if (type == IOMMU_DOMAIN_DMA &&
> iommu_get_dma_cookie(&rk_domain->domain))
> - goto err_unreg_pdev;
> + return NULL;
>
> /*
> * rk32xx iommus use a 2 level pagetable.
> @@ -1015,11 +1006,10 @@ static struct iommu_domain *rk_iommu_domain_alloc(unsigned type)
> if (!rk_domain->dt)
> goto err_put_cookie;
>
> - iommu_dev = &pdev->dev;
> - rk_domain->dt_dma = dma_map_single(iommu_dev, rk_domain->dt,
> + rk_domain->dt_dma = dma_map_single(dma_dev, rk_domain->dt,
> SPAGE_SIZE, DMA_TO_DEVICE);
> - if (dma_mapping_error(iommu_dev, rk_domain->dt_dma)) {
> - dev_err(iommu_dev, "DMA map error for DT\n");
> + if (dma_mapping_error(dma_dev, rk_domain->dt_dma)) {
> + dev_err(dma_dev, "DMA map error for DT\n");
> goto err_free_dt;
> }
>
> @@ -1040,8 +1030,6 @@ static struct iommu_domain *rk_iommu_domain_alloc(unsigned type)
> err_put_cookie:
> if (type == IOMMU_DOMAIN_DMA)
> iommu_put_dma_cookie(&rk_domain->domain);
> -err_unreg_pdev:
> - platform_device_unregister(pdev);
>
> return NULL;
> }
> @@ -1058,20 +1046,18 @@ static void rk_iommu_domain_free(struct iommu_domain *domain)
> if (rk_dte_is_pt_valid(dte)) {
> phys_addr_t pt_phys = rk_dte_pt_address(dte);
> u32 *page_table = phys_to_virt(pt_phys);
> - dma_unmap_single(&rk_domain->pdev->dev, pt_phys,
> + dma_unmap_single(dma_dev, pt_phys,
> SPAGE_SIZE, DMA_TO_DEVICE);
> free_page((unsigned long)page_table);
> }
> }
>
> - dma_unmap_single(&rk_domain->pdev->dev, rk_domain->dt_dma,
> + dma_unmap_single(dma_dev, rk_domain->dt_dma,
> SPAGE_SIZE, DMA_TO_DEVICE);
> free_page((unsigned long)rk_domain->dt);
>
> if (domain->type == IOMMU_DOMAIN_DMA)
> iommu_put_dma_cookie(&rk_domain->domain);
> -
> - platform_device_unregister(rk_domain->pdev);
> }
>
> static bool rk_iommu_is_dev_iommu_master(struct device *dev)
> @@ -1194,30 +1180,6 @@ static const struct iommu_ops rk_iommu_ops = {
> .pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP,
> };
>
> -static int rk_iommu_domain_probe(struct platform_device *pdev)
> -{
> - struct device *dev = &pdev->dev;
> -
> - dev->dma_parms = devm_kzalloc(dev, sizeof(*dev->dma_parms), GFP_KERNEL);
> - if (!dev->dma_parms)
> - return -ENOMEM;
> -
> - /* Set dma_ops for dev, otherwise it would be dummy_dma_ops */
> - arch_setup_dma_ops(dev, 0, DMA_BIT_MASK(32), NULL, false);
> -
> - dma_set_max_seg_size(dev, DMA_BIT_MASK(32));
> - dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
> -
> - return 0;
> -}
> -
> -static struct platform_driver rk_iommu_domain_driver = {
> - .probe = rk_iommu_domain_probe,
> - .driver = {
> - .name = "rk_iommu_domain",
> - },
> -};
> -
> static int rk_iommu_probe(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> @@ -1278,6 +1240,14 @@ static int rk_iommu_probe(struct platform_device *pdev)
> if (err)
> goto err_remove_sysfs;
>
> + /*
> + * Use the first registered IOMMU device for domain to use with DMA
> + * API, since a domain might not physically correspond to a single
> + * IOMMU device..
> + */
> + if (!dma_dev)
> + dma_dev = &pdev->dev;
> +
> return 0;
> err_remove_sysfs:
> iommu_device_sysfs_remove(&iommu->iommu);
> @@ -1316,14 +1286,7 @@ static int __init rk_iommu_init(void)
> if (ret)
> return ret;
>
> - ret = platform_driver_register(&rk_iommu_domain_driver);
> - if (ret)
> - return ret;
> -
> - ret = platform_driver_register(&rk_iommu_driver);
> - if (ret)
> - platform_driver_unregister(&rk_iommu_domain_driver);
> - return ret;
> + return platform_driver_register(&rk_iommu_driver);
> }
> subsys_initcall(rk_iommu_init);
>
>
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