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iommu: io-pgtable: Add ARM Mali midgard MMU page table format
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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@arm.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: iommu@lists.linux-foundation.org
Acked-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190409205427.6943-2-robh@kernel.org
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Rob Herring committed Apr 12, 2019
1 parent 0eb2766 commit d08d42d
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Showing 3 changed files with 77 additions and 22 deletions.
91 changes: 69 additions & 22 deletions drivers/iommu/io-pgtable-arm.c
Original file line number Diff line number Diff line change
Expand Up @@ -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))

Expand All @@ -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;

Expand All @@ -198,6 +197,15 @@ struct arm_lpae_io_pgtable {

typedef u64 arm_lpae_iopte;

static inline bool iopte_leaf(arm_lpae_iopte pte, int lvl,
enum io_pgtable_fmt fmt)
{
if (lvl == (ARM_LPAE_MAX_LEVELS - 1) && fmt != ARM_MALI_LPAE)
return iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_PAGE;

return iopte_type(pte, lvl) == ARM_LPAE_PTE_TYPE_BLOCK;
}

static arm_lpae_iopte paddr_to_iopte(phys_addr_t paddr,
struct arm_lpae_io_pgtable *data)
{
Expand Down Expand Up @@ -303,12 +311,14 @@ 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)
if (data->iop.fmt != ARM_MALI_LPAE && lvl == ARM_LPAE_MAX_LEVELS - 1)
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);
Expand All @@ -321,7 +331,7 @@ 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;
Expand Down Expand Up @@ -409,7 +419,7 @@ 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 */
Expand All @@ -429,31 +439,37 @@ 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;
}

/*
* Note that this logic is structured to accommodate Mali LPAE
* having stage-1-like attributes but stage-2-like permissions.
*/
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)
Expand Down Expand Up @@ -511,7 +527,7 @@ 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));
Expand Down Expand Up @@ -602,7 +618,7 @@ 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);
Expand All @@ -621,7 +637,7 @@ 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
Expand Down Expand Up @@ -669,7 +685,7 @@ 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 */
Expand Down Expand Up @@ -995,6 +1011,32 @@ 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,
Expand All @@ -1015,6 +1057,11 @@ 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;
Expand Down
1 change: 1 addition & 0 deletions drivers/iommu/io-pgtable.c
Original file line number Diff line number Diff line change
Expand Up @@ -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,
Expand Down
7 changes: 7 additions & 0 deletions include/linux/io-pgtable.h
Original file line number Diff line number Diff line change
Expand Up @@ -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,
};

Expand Down Expand Up @@ -108,6 +109,11 @@ struct io_pgtable_cfg {
u32 nmrr;
u32 prrr;
} arm_v7s_cfg;

struct {
u64 transtab;
u64 memattr;
} arm_mali_lpae_cfg;
};
};

Expand Down Expand Up @@ -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 */

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