diff mbox

[v2,10/13] iommu/rockchip: Use IOMMU device for dma mapping operations

Message ID 20180116132540.18939-11-jeffy.chen@rock-chips.com (mailing list archive)
State New, archived
Headers show

Commit Message

Jeffy Chen Jan. 16, 2018, 1:25 p.m. UTC 
Use the first registered IOMMU device for dma mapping operations, and
drop the domain platform device.

This is similar to exynos iommu driver.

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
---

Changes in v2: None

 drivers/iommu/rockchip-iommu.c | 91 +++++++++++-------------------------------
 1 file changed, 24 insertions(+), 67 deletions(-)

Comments

Tomasz Figa Jan. 17, 2018, 5:37 a.m. UTC | #1 
On Tue, Jan 16, 2018 at 10:25 PM, Jeffy Chen <jeffy.chen@rock-chips.com> wrote:
> Use the first registered IOMMU device for dma mapping operations, and
> drop the domain platform device.
>
> This is similar to exynos iommu driver.
>
> Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> ---
>
> Changes in v2: None
>
>  drivers/iommu/rockchip-iommu.c | 91 +++++++++++-------------------------------
>  1 file changed, 24 insertions(+), 67 deletions(-)

Looks good to me, but we need to remove platform driver .remove(), as
it was done for Exynos IOMMU as well. With that fixed (probably
squashed to the patch that prohibits unbind):

Reviewed-by: Tomasz Figa <tfiga@chromium.org>

Best regards,
Tomasz
diff mbox

Patch

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index ea4df162108b..51e4f982c4a6 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -78,7 +78,6 @@ 
 
 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 */
@@ -100,12 +99,14 @@  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)
@@ -692,7 +693,6 @@  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;
@@ -710,9 +710,9 @@  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);
 	}
@@ -987,29 +987,20 @@  static int rk_iommu_attach_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.
@@ -1020,11 +1011,10 @@  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;
 	}
 
@@ -1045,8 +1035,6 @@  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;
 }
@@ -1063,20 +1051,18 @@  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)
@@ -1202,30 +1188,6 @@  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;
@@ -1288,6 +1250,14 @@  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;
+
 	bus_set_iommu(&platform_bus_type, &rk_iommu_ops);
 
 	return 0;
@@ -1327,24 +1297,11 @@  static struct platform_driver rk_iommu_driver = {
 
 static int __init rk_iommu_init(void)
 {
-	int 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 0;
+	return platform_driver_register(&rk_iommu_driver);
 }
 static void __exit rk_iommu_exit(void)
 {
 	platform_driver_unregister(&rk_iommu_driver);
-	platform_driver_unregister(&rk_iommu_domain_driver);
 }
 
 subsys_initcall(rk_iommu_init);