[PATCH 5.15 211/244] iommu/io-pgtable-arm-v7s: Add a quirk to allow pgtable PA up to 35bit

Greg Kroah-Hartman
2022-08-23T10:27:06Z

From: Yunfei Wang <yf.wang@mediatek.com>

[ Upstream commit bfdd231374181254742c5e2faef0bef2d30c0ee4 ]

Single memory zone feature will remove ZONE_DMA32 and ZONE_DMA and
cause pgtable PA size larger than 32bit.

Since Mediatek IOMMU hardware support at most 35bit PA in pgtable,
so add a quirk to allow the PA of pgtables support up to bit35.

Signed-off-by: Ning Li <ning.li@mediatek.com>
Signed-off-by: Yunfei Wang <yf.wang@mediatek.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20220630092927.24925-2-yf.wang@mediatek.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/iommu/io-pgtable-arm-v7s.c | 75 ++++++++++++++++++++++--------
include/linux/io-pgtable.h | 15 ++++--
2 files changed, 66 insertions(+), 24 deletions(-)

diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c
index be066c1503d3..ba3115fd0f86 100644
--- a/drivers/iommu/io-pgtable-arm-v7s.c
+++ b/drivers/iommu/io-pgtable-arm-v7s.c
@@ -182,14 +182,8 @@ static bool arm_v7s_is_mtk_enabled(struct io_pgtable_cfg *cfg)
(cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_EXT);
}

-static arm_v7s_iopte paddr_to_iopte(phys_addr_t paddr, int lvl,
- struct io_pgtable_cfg *cfg)
+static arm_v7s_iopte to_mtk_iopte(phys_addr_t paddr, arm_v7s_iopte pte)
{
- arm_v7s_iopte pte = paddr & ARM_V7S_LVL_MASK(lvl);
-
- if (!arm_v7s_is_mtk_enabled(cfg))
- return pte;
-
if (paddr & BIT_ULL(32))
pte |= ARM_V7S_ATTR_MTK_PA_BIT32;
if (paddr & BIT_ULL(33))
@@ -199,6 +193,17 @@ static arm_v7s_iopte paddr_to_iopte(phys_addr_t paddr, int lvl,
return pte;
}

+static arm_v7s_iopte paddr_to_iopte(phys_addr_t paddr, int lvl,
+ struct io_pgtable_cfg *cfg)
+{
+ arm_v7s_iopte pte = paddr & ARM_V7S_LVL_MASK(lvl);
+
+ if (arm_v7s_is_mtk_enabled(cfg))
+ return to_mtk_iopte(paddr, pte);
+
+ return pte;
+}
+
static phys_addr_t iopte_to_paddr(arm_v7s_iopte pte, int lvl,
struct io_pgtable_cfg *cfg)
{
@@ -240,10 +245,17 @@ static void *__arm_v7s_alloc_table(int lvl, gfp_t gfp,
dma_addr_t dma;
size_t size = ARM_V7S_TABLE_SIZE(lvl, cfg);
void *table = NULL;
+ gfp_t gfp_l1;
+
+ /*
+ * ARM_MTK_TTBR_EXT extend the translation table base support larger
+ * memory address.
+ */
+ gfp_l1 = cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT ?
+ GFP_KERNEL : ARM_V7S_TABLE_GFP_DMA;

if (lvl == 1)
- table = (void *)__get_free_pages(
- __GFP_ZERO | ARM_V7S_TABLE_GFP_DMA, get_order(size));
+ table = (void *)__get_free_pages(gfp_l1 | __GFP_ZERO, get_order(size));
else if (lvl == 2)
table = kmem_cache_zalloc(data->l2_tables, gfp);

@@ -251,7 +263,8 @@ static void *__arm_v7s_alloc_table(int lvl, gfp_t gfp,
return NULL;

phys = virt_to_phys(table);
- if (phys != (arm_v7s_iopte)phys) {
+ if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT ?
+ phys >= (1ULL << cfg->oas) : phys != (arm_v7s_iopte)phys) {
/* Doesn't fit in PTE */
dev_err(dev, "Page table does not fit in PTE: %pa", &phys);
goto out_free;
@@ -457,9 +470,14 @@ static arm_v7s_iopte arm_v7s_install_table(arm_v7s_iopte *table,
arm_v7s_iopte curr,
struct io_pgtable_cfg *cfg)
{
+ phys_addr_t phys = virt_to_phys(table);
arm_v7s_iopte old, new;

- new = virt_to_phys(table) | ARM_V7S_PTE_TYPE_TABLE;
+ new = phys | ARM_V7S_PTE_TYPE_TABLE;
+
+ if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT)
+ new = to_mtk_iopte(phys, new);
+
if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
new |= ARM_V7S_ATTR_NS_TABLE;

@@ -779,6 +797,8 @@ static struct io_pgtable *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg,
void *cookie)
{
struct arm_v7s_io_pgtable *data;
+ slab_flags_t slab_flag;
+ phys_addr_t paddr;

if (cfg->ias > (arm_v7s_is_mtk_enabled(cfg) ? 34 : ARM_V7S_ADDR_BITS))
return NULL;
@@ -788,7 +808,8 @@ static struct io_pgtable *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg,

if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_NS |
IO_PGTABLE_QUIRK_NO_PERMS |
- IO_PGTABLE_QUIRK_ARM_MTK_EXT))
+ IO_PGTABLE_QUIRK_ARM_MTK_EXT |
+ IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT))
return NULL;

/* If ARM_MTK_4GB is enabled, the NO_PERMS is also expected. */
@@ -796,15 +817,27 @@ static struct io_pgtable *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg,
!(cfg->quirks & IO_PGTABLE_QUIRK_NO_PERMS))
return NULL;

+ if ((cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT) &&
+ !arm_v7s_is_mtk_enabled(cfg))
+ return NULL;
+
data = kmalloc(sizeof(*data), GFP_KERNEL);
if (!data)
return NULL;

spin_lock_init(&data->split_lock);
+
+ /*
+ * ARM_MTK_TTBR_EXT extend the translation table base support larger
+ * memory address.
+ */
+ slab_flag = cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT ?
+ 0 : ARM_V7S_TABLE_SLAB_FLAGS;
+
data->l2_tables = kmem_cache_create("io-pgtable_armv7s_l2",
ARM_V7S_TABLE_SIZE(2, cfg),
ARM_V7S_TABLE_SIZE(2, cfg),
- ARM_V7S_TABLE_SLAB_FLAGS, NULL);
+ slab_flag, NULL);
if (!data->l2_tables)
goto out_free_data;

@@ -850,12 +883,16 @@ static struct io_pgtable *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg,
wmb();

/* TTBR */
- cfg->arm_v7s_cfg.ttbr = virt_to_phys(data->pgd) | ARM_V7S_TTBR_S |
- (cfg->coherent_walk ? (ARM_V7S_TTBR_NOS |
- ARM_V7S_TTBR_IRGN_ATTR(ARM_V7S_RGN_WBWA) |
- ARM_V7S_TTBR_ORGN_ATTR(ARM_V7S_RGN_WBWA)) :
- (ARM_V7S_TTBR_IRGN_ATTR(ARM_V7S_RGN_NC) |
- ARM_V7S_TTBR_ORGN_ATTR(ARM_V7S_RGN_NC)));
+ paddr = virt_to_phys(data->pgd);
+ if (arm_v7s_is_mtk_enabled(cfg))
+ cfg->arm_v7s_cfg.ttbr = paddr | upper_32_bits(paddr);
+ else
+ cfg->arm_v7s_cfg.ttbr = paddr | ARM_V7S_TTBR_S |
+ (cfg->coherent_walk ? (ARM_V7S_TTBR_NOS |
+ ARM_V7S_TTBR_IRGN_ATTR(ARM_V7S_RGN_WBWA) |
+ ARM_V7S_TTBR_ORGN_ATTR(ARM_V7S_RGN_WBWA)) :
+ (ARM_V7S_TTBR_IRGN_ATTR(ARM_V7S_RGN_NC) |
+ ARM_V7S_TTBR_ORGN_ATTR(ARM_V7S_RGN_NC)));
return &data->iop;

out_free_data:
diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
index 86af6f0a00a2..ca98aeadcc80 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -74,17 +74,22 @@ struct io_pgtable_cfg {
* to support up to 35 bits PA where the bit32, bit33 and bit34 are
* encoded in the bit9, bit4 and bit5 of the PTE respectively.
*
+ * IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT: (ARM v7s format) MediaTek IOMMUs
+ * extend the translation table base support up to 35 bits PA, the
+ * encoding format is same with IO_PGTABLE_QUIRK_ARM_MTK_EXT.
+ *
* IO_PGTABLE_QUIRK_ARM_TTBR1: (ARM LPAE format) Configure the table
* for use in the upper half of a split address space.
*
* IO_PGTABLE_QUIRK_ARM_OUTER_WBWA: Override the outer-cacheability
* attributes set in the TCR for a non-coherent page-table walker.
*/
- #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
- #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
- #define IO_PGTABLE_QUIRK_ARM_MTK_EXT BIT(3)
- #define IO_PGTABLE_QUIRK_ARM_TTBR1 BIT(5)
- #define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA BIT(6)
+ #define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
+ #define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
+ #define IO_PGTABLE_QUIRK_ARM_MTK_EXT BIT(3)
+ #define IO_PGTABLE_QUIRK_ARM_MTK_TTBR_EXT BIT(4)
+ #define IO_PGTABLE_QUIRK_ARM_TTBR1 BIT(5)
+ #define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA BIT(6)
unsigned long quirks;
unsigned long pgsize_bitmap;
unsigned int ias;
--
2.35.1