iommu/sprd: Add support for reattaching an existing domain

This IOMMU driver should allow a domain to be attached more than once.

If IOMMU is reattaching to the same domain which is attached, there's
nothing to be done.

If reattching to a previously-used domain, do not alloc DMA buffer
again which stores address mapping table to avoid memory leak.

Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20230331033124.864691-3-zhang.lyra@gmail.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Chunyan Zhang 2023-03-31 11:31:24 +08:00 committed by Joerg Roedel
parent 9afea57384
commit 816c698c05
1 changed files with 19 additions and 6 deletions

View File

@ -62,6 +62,7 @@ enum sprd_iommu_version {
* @eb: gate clock which controls IOMMU access
*/
struct sprd_iommu_device {
struct sprd_iommu_domain *dom;
enum sprd_iommu_version ver;
u32 *prot_page_va;
dma_addr_t prot_page_pa;
@ -252,15 +253,27 @@ static int sprd_iommu_attach_device(struct iommu_domain *domain,
struct sprd_iommu_domain *dom = to_sprd_domain(domain);
size_t pgt_size = sprd_iommu_pgt_size(domain);
if (dom->sdev)
return -EINVAL;
/* The device is attached to this domain */
if (sdev->dom == dom)
return 0;
dom->pgt_va = dma_alloc_coherent(sdev->dev, pgt_size, &dom->pgt_pa, GFP_KERNEL);
if (!dom->pgt_va)
return -ENOMEM;
/* The first time that domain is attaching to a device */
if (!dom->pgt_va) {
dom->pgt_va = dma_alloc_coherent(sdev->dev, pgt_size, &dom->pgt_pa, GFP_KERNEL);
if (!dom->pgt_va)
return -ENOMEM;
dom->sdev = sdev;
dom->sdev = sdev;
}
sdev->dom = dom;
/*
* One sprd IOMMU serves one client device only, disabled it before
* configure mapping table to avoid access conflict in case other
* mapping table is stored in.
*/
sprd_iommu_hw_en(sdev, false);
sprd_iommu_first_ppn(dom);
sprd_iommu_first_vpn(dom);
sprd_iommu_vpn_range(dom);