Subject: [PATCH v3 19/32] iommu/sprd: implement iova_to_phys_length

From: Guanghui Feng <[email-masked]>
Date: Wed, 3 Jun 2026 23:17:51 +0800

Implement iova_to_phys_length for Spreadtrum IOMMU driver,
returning the actual PTE mapping size.

Signed-off-by: Guanghui Feng <[email-masked]>
---
 drivers/iommu/sprd-iommu.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/iommu/sprd-iommu.c b/drivers/iommu/sprd-iommu.c
index c1a34445d244..3c04ec040d96 100644
--- a/drivers/iommu/sprd-iommu.c
+++ b/drivers/iommu/sprd-iommu.c
@@ -366,8 +366,9 @@ static void sprd_iommu_sync(struct iommu_domain *domain,
 	sprd_iommu_sync_map(domain, 0, 0);
 }
 
-static phys_addr_t sprd_iommu_iova_to_phys(struct iommu_domain *domain,
-					   dma_addr_t iova)
+static phys_addr_t sprd_iommu_iova_to_phys_length(struct iommu_domain *domain,
+						  dma_addr_t iova,
+						  size_t *mapped_length)
 {
 	struct sprd_iommu_domain *dom = to_sprd_domain(domain);
 	unsigned long flags;
@@ -376,13 +377,19 @@ static phys_addr_t sprd_iommu_iova_to_phys(struct iommu_domain *domain,
 	unsigned long end = domain->geometry.aperture_end;
 
 	if (WARN_ON(iova < start || iova > end))
-		return 0;
+		return PHYS_ADDR_MAX;
 
 	spin_lock_irqsave(&dom->pgtlock, flags);
 	pa = *(dom->pgt_va + ((iova - start) >> SPRD_IOMMU_PAGE_SHIFT));
-	pa = (pa << SPRD_IOMMU_PAGE_SHIFT) + ((iova - start) & (SPRD_IOMMU_PAGE_SIZE - 1));
 	spin_unlock_irqrestore(&dom->pgtlock, flags);
 
+	if (!pa)
+		return PHYS_ADDR_MAX;
+
+	pa = (pa << SPRD_IOMMU_PAGE_SHIFT) + ((iova - start) & (SPRD_IOMMU_PAGE_SIZE - 1));
+	if (mapped_length)
+		*mapped_length = SPRD_IOMMU_PAGE_SIZE;
+
 	return pa;
 }
 
@@ -420,7 +427,7 @@ static const struct iommu_ops sprd_iommu_ops = {
 		.unmap_pages	= sprd_iommu_unmap,
 		.iotlb_sync_map	= sprd_iommu_sync_map,
 		.iotlb_sync	= sprd_iommu_sync,
-		.iova_to_phys	= sprd_iommu_iova_to_phys,
+		.iova_to_phys_length	= sprd_iommu_iova_to_phys_length,
 		.free		= sprd_iommu_domain_free,
 	}
 };
-- 
2.43.7