lede/target/linux/silicon/patches-5.19/0048-iommu-io-pgtable-Add-DART-subpage-protection-support.patch

55 lines
1.8 KiB
Diff

From cd16901670e12ae1185f2488e74f50ce5d72c5fb Mon Sep 17 00:00:00 2001
From: Sven Peter <sven@svenpeter.dev>
Date: Wed, 17 Nov 2021 19:40:16 +0100
Subject: [PATCH 048/171] 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 <sven@svenpeter.dev>
Signed-off-by: Janne Grunau <j@jannau.net>
Commit-changes: 3
- apply change to io-pgtable-dart.c
---
drivers/iommu/io-pgtable-dart.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/iommu/io-pgtable-dart.c b/drivers/iommu/io-pgtable-dart.c
index 0c5222942c65..fa8025c03bb5 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 <linux/atomic.h>
+#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/io-pgtable.h>
#include <linux/kernel.h>
@@ -63,6 +64,9 @@
/* Calculate the block/page mapping size at level l for pagetable in d. */
#define DART_BLOCK_SIZE(l, d) (1ULL << DART_LVL_SHIFT(l, d))
+#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 */
@@ -140,6 +144,10 @@ static void __dart_init_pte(struct dart_io_pgtable *data,
pte |= APPLE_DART_PTE_VALID;
+ /* 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);
+
for (i = 0; i < num_entries; i++)
ptep[i] = pte | paddr_to_iopte(paddr + i * sz, data);
}
--
2.34.1