iommu/dart: Use virtual memory ttbr entries in apple_dart_cfg

Locked DARTs can not modify ttbr entries. To ensure atomic updates of
PTEs in the L1 table the DART driver will copy entries to the
preallocated L1 table. This requires access to io-pgtable-dart's tables.
For all other DARTs this moves virt_to_phys() calls into the DART
driver.

Signed-off-by: Janne Grunau <j@jannau.net>

Author: jannau

drivers/iommu/apple-dart.c

@@ -583,9 +583,10 @@ apple_dart_setup_translation(struct apple_dart_domain *domain,
 	struct io_pgtable_cfg *pgtbl_cfg =
 		&io_pgtable_ops_to_pgtable(domain->pgtbl_ops)->cfg;
 
-	for (i = 0; i < pgtbl_cfg->apple_dart_cfg.n_ttbrs; ++i)
-		apple_dart_hw_set_ttbr(stream_map, i,
-				       pgtbl_cfg->apple_dart_cfg.ttbr[i]);
+	for (i = 0; i < pgtbl_cfg->apple_dart_cfg.n_ttbrs; ++i) {
+		u64 ttbr = virt_to_phys(pgtbl_cfg->apple_dart_cfg.ttbr[i]);
+		apple_dart_hw_set_ttbr(stream_map, i, ttbr);
+	}
 	for (; i < stream_map->dart->hw->ttbr_count; ++i)
 		apple_dart_hw_clear_ttbr(stream_map, i);
 

drivers/iommu/io-pgtable-dart.c

@@ -435,7 +435,7 @@ apple_dart_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
 			iommu_alloc_pages_sz(GFP_KERNEL, DART_GRANULE(data));
 		if (!data->pgd[i])
 			goto out_free_data;
-		cfg->apple_dart_cfg.ttbr[i] = virt_to_phys(data->pgd[i]);
+		cfg->apple_dart_cfg.ttbr[i] = data->pgd[i];
 	}
 
 	return &data->iop;

include/linux/io-pgtable.h

@@ -176,7 +176,7 @@ struct io_pgtable_cfg {
 		} arm_mali_lpae_cfg;
 
 		struct {
-			u64 ttbr[4];
+			void *ttbr[4];
 			u32 n_ttbrs;
 			u32 n_levels;
 		} apple_dart_cfg;