Apple's DART iommu uses a pagetable format that shares some
similarities with the ones already implemented by io-pgtable.c.
Add a new format variant to support the required differences
so that we don't have to duplicate the pagetable handling code.
Reviewed-by: Alexander Graf <g...@amazon.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzw...@collabora.com>
Reviewed-by: Robin Murphy <robin.mur...@arm.com>
Signed-off-by: Sven Peter <s...@svenpeter.dev>
---
drivers/iommu/io-pgtable-arm.c | 63 ++++++++++++++++++++++++++++++++++
drivers/iommu/io-pgtable.c | 1 +
include/linux/io-pgtable.h | 7 ++++
3 files changed, 71 insertions(+)
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 053df4048a29..0779eb96bd29 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -130,6 +130,9 @@
#define ARM_MALI_LPAE_MEMATTR_IMP_DEF 0x88ULL
#define ARM_MALI_LPAE_MEMATTR_WRITE_ALLOC 0x8DULL
+#define APPLE_DART_PTE_PROT_NO_WRITE (1<<7)
+#define APPLE_DART_PTE_PROT_NO_READ (1<<8)
+
/* IOPTE accessors */
#define iopte_deref(pte,d) __va(iopte_to_paddr(pte, d))
@@ -402,6 +405,15 @@ static arm_lpae_iopte arm_lpae_prot_to_pte(struct
arm_lpae_io_pgtable *data,
{
arm_lpae_iopte pte;
+ if (data->iop.fmt == APPLE_DART) {
+ pte = 0;
+ if (!(prot & IOMMU_WRITE))
+ pte |= APPLE_DART_PTE_PROT_NO_WRITE;
+ if (!(prot & IOMMU_READ))
+ pte |= APPLE_DART_PTE_PROT_NO_READ;
+ return pte;
+ }
+
if (data->iop.fmt == ARM_64_LPAE_S1 ||
data->iop.fmt == ARM_32_LPAE_S1) {
pte = ARM_LPAE_PTE_nG;
@@ -1102,6 +1114,52 @@ arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg,
void *cookie)
return NULL;
}
+static struct io_pgtable *
+apple_dart_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
+{
+ struct arm_lpae_io_pgtable *data;
+ int i;
+
+ if (cfg->oas > 36)
+ return NULL;
+
+ data = arm_lpae_alloc_pgtable(cfg);
+ if (!data)
+ return NULL;
+
+ /*
+ * The table format itself always uses two levels, but the total VA
+ * space is mapped by four separate tables, making the MMIO registers
+ * an effective "level 1". For simplicity, though, we treat this
+ * equivalently to LPAE stage 2 concatenation at level 2, with the
+ * additional TTBRs each just pointing at consecutive pages.
+ */
+ if (data->start_level < 1)
+ goto out_free_data;
+ if (data->start_level == 1 && data->pgd_bits > 2)
+ goto out_free_data;
+ if (data->start_level > 1)
+ data->pgd_bits = 0;
+ data->start_level = 2;
+ cfg->apple_dart_cfg.n_ttbrs = 1 << data->pgd_bits;
+ data->pgd_bits += data->bits_per_level;
+
+ data->pgd = __arm_lpae_alloc_pages(ARM_LPAE_PGD_SIZE(data), GFP_KERNEL,
+ cfg);
+ if (!data->pgd)
+ goto out_free_data;
+
+ for (i = 0; i < cfg->apple_dart_cfg.n_ttbrs; ++i)
+ cfg->apple_dart_cfg.ttbr[i] =
+ virt_to_phys(data->pgd + i * ARM_LPAE_GRANULE(data));
+
+ return &data->iop;
+
+out_free_data:
+ kfree(data);
+ return NULL;
+}
+
struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns = {
.alloc = arm_64_lpae_alloc_pgtable_s1,
.free = arm_lpae_free_pgtable,
@@ -1127,6 +1185,11 @@ struct io_pgtable_init_fns
io_pgtable_arm_mali_lpae_init_fns = {
.free = arm_lpae_free_pgtable,
};
+struct io_pgtable_init_fns io_pgtable_apple_dart_init_fns = {
+ .alloc = apple_dart_alloc_pgtable,
+ .free = arm_lpae_free_pgtable,
+};
+
#ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST
static struct io_pgtable_cfg *cfg_cookie __initdata;
diff --git a/drivers/iommu/io-pgtable.c b/drivers/iommu/io-pgtable.c
index 6e9917ce980f..f4bfcef98297 100644
--- a/drivers/iommu/io-pgtable.c
+++ b/drivers/iommu/io-pgtable.c
@@ -20,6 +20,7 @@ io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = {
[ARM_64_LPAE_S1] = &io_pgtable_arm_64_lpae_s1_init_fns,
[ARM_64_LPAE_S2] = &io_pgtable_arm_64_lpae_s2_init_fns,
[ARM_MALI_LPAE] = &io_pgtable_arm_mali_lpae_init_fns,
+ [APPLE_DART] = &io_pgtable_apple_dart_init_fns,
#endif
#ifdef CONFIG_IOMMU_IO_PGTABLE_ARMV7S
[ARM_V7S] = &io_pgtable_arm_v7s_init_fns,
diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
index c43f3b899d2a..a738483fb4da 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -16,6 +16,7 @@ enum io_pgtable_fmt {
ARM_V7S,
ARM_MALI_LPAE,
AMD_IOMMU_V1,
+ APPLE_DART,
IO_PGTABLE_NUM_FMTS,
};
@@ -136,6 +137,11 @@ struct io_pgtable_cfg {
u64 transtab;
u64 memattr;
} arm_mali_lpae_cfg;
+
+ struct {
+ u64 ttbr[4];
+ u32 n_ttbrs;
+ } apple_dart_cfg;
};
};
@@ -254,5 +260,6 @@ extern struct io_pgtable_init_fns
io_pgtable_arm_64_lpae_s2_init_fns;
extern struct io_pgtable_init_fns io_pgtable_arm_v7s_init_fns;
extern struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns;
extern struct io_pgtable_init_fns io_pgtable_amd_iommu_v1_init_fns;
+extern struct io_pgtable_init_fns io_pgtable_apple_dart_init_fns;
#endif /* __IO_PGTABLE_H */
--
2.25.1
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