[PATCH v3 1/3] iommu: io-pgtable: Add ARM Mali midgard MMU page table format

From: Rob Herring
Date: Mon Apr 01 2019 - 03:47:45 EST


ARM Mali midgard GPU is similar to standard 64-bit stage 1 page tables, but
have a few differences. Add a new format type to represent the format. The
input address size is 48-bits and the output address size is 40-bits (and
possibly less?). Note that the later bifrost GPUs follow the standard
64-bit stage 1 format.

The differences in the format compared to 64-bit stage 1 format are:

The 3rd level page entry bits are 0x1 instead of 0x3 for page entries.

The access flags are not read-only and unprivileged, but read and write.
This is similar to stage 2 entries, but the memory attributes field matches
stage 1 being an index.

The nG bit is not set by the vendor driver. This one didn't seem to matter,
but we'll keep it aligned to the vendor driver.

Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: iommu@xxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Rob Herring <robh@xxxxxxxxxx>
---
Please ack this as I need to apply it to the drm-misc tree. Or we need a
stable branch with this patch.

v3:
- Rework arm_lpae_prot_to_pte as written by Robin
- Fill in complete register values for TRANSTAB and MEMATTR registers


drivers/iommu/io-pgtable-arm.c | 93 +++++++++++++++++++++++++---------
drivers/iommu/io-pgtable.c | 1 +
include/linux/io-pgtable.h | 7 +++
3 files changed, 77 insertions(+), 24 deletions(-)

diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index d3700ec15cbd..98551d0cff59 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -172,6 +172,10 @@
#define ARM_LPAE_MAIR_ATTR_IDX_CACHE 1
#define ARM_LPAE_MAIR_ATTR_IDX_DEV 2

+#define ARM_MALI_LPAE_TTBR_ADRMODE_TABLE (3u << 0)
+#define ARM_MALI_LPAE_TTBR_READ_INNER BIT(2)
+#define ARM_MALI_LPAE_TTBR_SHARE_OUTER BIT(4)
+
/* IOPTE accessors */
#define iopte_deref(pte,d) __va(iopte_to_paddr(pte, d))

@@ -180,11 +184,6 @@

#define iopte_prot(pte) ((pte) & ARM_LPAE_PTE_ATTR_MASK)

-#define iopte_leaf(pte,l) \
- (l == (ARM_LPAE_MAX_LEVELS - 1) ? \
- (iopte_type(pte,l) == ARM_LPAE_PTE_TYPE_PAGE) : \
- (iopte_type(pte,l) == ARM_LPAE_PTE_TYPE_BLOCK))
-
struct arm_lpae_io_pgtable {
struct io_pgtable iop;

@@ -198,6 +197,14 @@ struct arm_lpae_io_pgtable {

typedef u64 arm_lpae_iopte;

+static inline bool iopte_leaf(arm_lpae_iopte pte, int l, enum io_pgtable_fmt fmt)
+{
+ if ((l == (ARM_LPAE_MAX_LEVELS - 1)) && (fmt != ARM_MALI_LPAE))
+ return iopte_type(pte,l) == ARM_LPAE_PTE_TYPE_PAGE;
+
+ return iopte_type(pte,l) == ARM_LPAE_PTE_TYPE_BLOCK;
+}
+
static arm_lpae_iopte paddr_to_iopte(phys_addr_t paddr,
struct arm_lpae_io_pgtable *data)
{
@@ -303,12 +310,17 @@ static void __arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_NS)
pte |= ARM_LPAE_PTE_NS;

- if (lvl == ARM_LPAE_MAX_LEVELS - 1)
- pte |= ARM_LPAE_PTE_TYPE_PAGE;
- else
+ if (lvl == ARM_LPAE_MAX_LEVELS - 1) {
+ if (data->iop.fmt == ARM_MALI_LPAE)
+ pte |= ARM_LPAE_PTE_TYPE_BLOCK;
+ else
+ pte |= ARM_LPAE_PTE_TYPE_PAGE;
+ } else
pte |= ARM_LPAE_PTE_TYPE_BLOCK;

- pte |= ARM_LPAE_PTE_AF | ARM_LPAE_PTE_SH_IS;
+ if (data->iop.fmt != ARM_MALI_LPAE)
+ pte |= ARM_LPAE_PTE_AF;
+ pte |= ARM_LPAE_PTE_SH_IS;
pte |= paddr_to_iopte(paddr, data);

__arm_lpae_set_pte(ptep, pte, &data->iop.cfg);
@@ -321,7 +333,7 @@ static int arm_lpae_init_pte(struct arm_lpae_io_pgtable *data,
{
arm_lpae_iopte pte = *ptep;

- if (iopte_leaf(pte, lvl)) {
+ if (iopte_leaf(pte, lvl, data->iop.fmt)) {
/* We require an unmap first */
WARN_ON(!selftest_running);
return -EEXIST;
@@ -409,7 +421,7 @@ static int __arm_lpae_map(struct arm_lpae_io_pgtable *data, unsigned long iova,
__arm_lpae_sync_pte(ptep, cfg);
}

- if (pte && !iopte_leaf(pte, lvl)) {
+ if (pte && !iopte_leaf(pte, lvl, data->iop.fmt)) {
cptep = iopte_deref(pte, data);
} else if (pte) {
/* We require an unmap first */
@@ -429,31 +441,33 @@ static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
if (data->iop.fmt == ARM_64_LPAE_S1 ||
data->iop.fmt == ARM_32_LPAE_S1) {
pte = ARM_LPAE_PTE_nG;
-
if (!(prot & IOMMU_WRITE) && (prot & IOMMU_READ))
pte |= ARM_LPAE_PTE_AP_RDONLY;
-
if (!(prot & IOMMU_PRIV))
pte |= ARM_LPAE_PTE_AP_UNPRIV;
-
- if (prot & IOMMU_MMIO)
- pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV
- << ARM_LPAE_PTE_ATTRINDX_SHIFT);
- else if (prot & IOMMU_CACHE)
- pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE
- << ARM_LPAE_PTE_ATTRINDX_SHIFT);
} else {
pte = ARM_LPAE_PTE_HAP_FAULT;
if (prot & IOMMU_READ)
pte |= ARM_LPAE_PTE_HAP_READ;
if (prot & IOMMU_WRITE)
pte |= ARM_LPAE_PTE_HAP_WRITE;
+ }
+
+ if (data->iop.fmt == ARM_64_LPAE_S2 ||
+ data->iop.fmt == ARM_32_LPAE_S2) {
if (prot & IOMMU_MMIO)
pte |= ARM_LPAE_PTE_MEMATTR_DEV;
else if (prot & IOMMU_CACHE)
pte |= ARM_LPAE_PTE_MEMATTR_OIWB;
else
pte |= ARM_LPAE_PTE_MEMATTR_NC;
+ } else {
+ if (prot & IOMMU_MMIO)
+ pte |= (ARM_LPAE_MAIR_ATTR_IDX_DEV
+ << ARM_LPAE_PTE_ATTRINDX_SHIFT);
+ else if (prot & IOMMU_CACHE)
+ pte |= (ARM_LPAE_MAIR_ATTR_IDX_CACHE
+ << ARM_LPAE_PTE_ATTRINDX_SHIFT);
}

if (prot & IOMMU_NOEXEC)
@@ -511,7 +525,7 @@ static void __arm_lpae_free_pgtable(struct arm_lpae_io_pgtable *data, int lvl,
while (ptep != end) {
arm_lpae_iopte pte = *ptep++;

- if (!pte || iopte_leaf(pte, lvl))
+ if (!pte || iopte_leaf(pte, lvl, data->iop.fmt))
continue;

__arm_lpae_free_pgtable(data, lvl + 1, iopte_deref(pte, data));
@@ -602,7 +616,7 @@ static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
if (size == ARM_LPAE_BLOCK_SIZE(lvl, data)) {
__arm_lpae_set_pte(ptep, 0, &iop->cfg);

- if (!iopte_leaf(pte, lvl)) {
+ if (!iopte_leaf(pte, lvl, iop->fmt)) {
/* Also flush any partial walks */
io_pgtable_tlb_add_flush(iop, iova, size,
ARM_LPAE_GRANULE(data), false);
@@ -621,7 +635,7 @@ static size_t __arm_lpae_unmap(struct arm_lpae_io_pgtable *data,
}

return size;
- } else if (iopte_leaf(pte, lvl)) {
+ } else if (iopte_leaf(pte, lvl, iop->fmt)) {
/*
* Insert a table at the next level to map the old region,
* minus the part we want to unmap
@@ -669,7 +683,7 @@ static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops,
return 0;

/* Leaf entry? */
- if (iopte_leaf(pte,lvl))
+ if (iopte_leaf(pte, lvl, data->iop.fmt))
goto found_translation;

/* Take it to the next level */
@@ -995,6 +1009,32 @@ arm_32_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
return iop;
}

+static struct io_pgtable *
+arm_mali_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie)
+{
+ struct io_pgtable *iop;
+
+ if (cfg->ias != 48 || cfg->oas > 40)
+ return NULL;
+
+ cfg->pgsize_bitmap &= (SZ_4K | SZ_2M | SZ_1G);
+ iop = arm_64_lpae_alloc_pgtable_s1(cfg, cookie);
+ if (iop) {
+ u64 mair, ttbr;
+
+ /* Copy values as union fields overlap */
+ mair = cfg->arm_lpae_s1_cfg.mair[0];
+ ttbr = cfg->arm_lpae_s1_cfg.ttbr[0];
+
+ cfg->arm_mali_lpae_cfg.memattr = mair;
+ cfg->arm_mali_lpae_cfg.transtab = ttbr |
+ ARM_MALI_LPAE_TTBR_READ_INNER |
+ ARM_MALI_LPAE_TTBR_ADRMODE_TABLE;
+ }
+
+ return iop;
+}
+
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,
@@ -1015,6 +1055,11 @@ struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns = {
.free = arm_lpae_free_pgtable,
};

+struct io_pgtable_init_fns io_pgtable_arm_mali_lpae_init_fns = {
+ .alloc = arm_mali_lpae_alloc_pgtable,
+ .free = arm_lpae_free_pgtable,
+};
+
#ifdef CONFIG_IOMMU_IO_PGTABLE_LPAE_SELFTEST

static struct io_pgtable_cfg *cfg_cookie;
diff --git a/drivers/iommu/io-pgtable.c b/drivers/iommu/io-pgtable.c
index 93f2880be6c6..5227cfdbb65b 100644
--- a/drivers/iommu/io-pgtable.c
+++ b/drivers/iommu/io-pgtable.c
@@ -30,6 +30,7 @@ io_pgtable_init_table[IO_PGTABLE_NUM_FMTS] = {
[ARM_32_LPAE_S2] = &io_pgtable_arm_32_lpae_s2_init_fns,
[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,
#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 47d5ae559329..76969a564831 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -12,6 +12,7 @@ enum io_pgtable_fmt {
ARM_64_LPAE_S1,
ARM_64_LPAE_S2,
ARM_V7S,
+ ARM_MALI_LPAE,
IO_PGTABLE_NUM_FMTS,
};

@@ -108,6 +109,11 @@ struct io_pgtable_cfg {
u32 nmrr;
u32 prrr;
} arm_v7s_cfg;
+
+ struct {
+ u64 transtab;
+ u64 memattr;
+ } arm_mali_lpae_cfg;
};
};

@@ -209,5 +215,6 @@ extern struct io_pgtable_init_fns io_pgtable_arm_32_lpae_s2_init_fns;
extern struct io_pgtable_init_fns io_pgtable_arm_64_lpae_s1_init_fns;
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;

#endif /* __IO_PGTABLE_H */
--
2.19.1