From d8fe365a4f1c1aa5e2da3e41f50a08c9bd8d6112 Mon Sep 17 00:00:00 2001 From: Sven Peter Date: Fri, 16 Sep 2022 11:41:50 +0200 Subject: iommu/io-pgtable: Add DART subpage protection support DART allows to only expose a subpage to the device. While this is an optional feature on the M1 DARTs the new ones present on the Pro/Max models require this field in every PTE. Signed-off-by: Sven Peter Signed-off-by: Janne Grunau Reviewed-by: Rob Herring Acked-by: Hector Martin Link: https://lore.kernel.org/r/20220916094152.87137-4-j@jannau.net Signed-off-by: Joerg Roedel --- drivers/iommu/io-pgtable-dart.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'drivers/iommu') diff --git a/drivers/iommu/io-pgtable-dart.c b/drivers/iommu/io-pgtable-dart.c index 8ca1ea313a80..fc76b6168055 100644 --- a/drivers/iommu/io-pgtable-dart.c +++ b/drivers/iommu/io-pgtable-dart.c @@ -14,6 +14,7 @@ #define pr_fmt(fmt) "dart io-pgtable: " fmt #include +#include #include #include #include @@ -40,6 +41,9 @@ #define DART_PTES_PER_TABLE(d) \ (DART_GRANULE(d) >> ilog2(sizeof(dart_iopte))) +#define APPLE_DART_PTE_SUBPAGE_START GENMASK_ULL(63, 52) +#define APPLE_DART_PTE_SUBPAGE_END GENMASK_ULL(51, 40) + #define APPLE_DART1_PADDR_MASK GENMASK_ULL(35, 12) /* Apple DART1 protection bits */ @@ -107,6 +111,10 @@ static int dart_init_pte(struct dart_io_pgtable *data, return -EEXIST; } + /* subpage protection: always allow access to the entire page */ + pte |= FIELD_PREP(APPLE_DART_PTE_SUBPAGE_START, 0); + pte |= FIELD_PREP(APPLE_DART_PTE_SUBPAGE_END, 0xfff); + pte |= APPLE_DART1_PTE_PROT_SP_DIS; pte |= APPLE_DART_PTE_VALID; -- cgit v1.2.3