The nature of the LPAE format means that data->pg_shift is always
redundant with data->bits_per_level, since they represent the size of a
page and the number of PTEs per page respectively, and the size of a PTE
is constant. Thus it works out more efficient to only store the latter,
and derive the former via a trivial addition where necessary.
Signed-off-by: Robin Murphy <robin.mur...@arm.com>
---
drivers/iommu/io-pgtable-arm.c | 29 +++++++++++++----------------
1 file changed, 13 insertions(+), 16 deletions(-)
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 4b1483eb0ccf..15b4927ce36b 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -36,10 +36,11 @@
* in a virtual address mapped by the pagetable in d.
*/
#define ARM_LPAE_LVL_SHIFT(l,d)
\
- (((ARM_LPAE_MAX_LEVELS - 1 - (l)) * (d)->bits_per_level) + \
- (d)->pg_shift)
+ (((ARM_LPAE_MAX_LEVELS - (l)) * (d)->bits_per_level) + \
+ ilog2(sizeof(arm_lpae_iopte)))
-#define ARM_LPAE_GRANULE(d) (1UL << (d)->pg_shift)
+#define ARM_LPAE_GRANULE(d) \
+ (sizeof(arm_lpae_iopte) << (d)->bits_per_level)
#define ARM_LPAE_PGD_SIZE(d) \
(sizeof(arm_lpae_iopte) << (d)->pgd_bits)
@@ -55,9 +56,7 @@
((1 << ((d)->bits_per_level + ARM_LPAE_PGD_IDX(l,d))) - 1))
/* Calculate the block/page mapping size at level l for pagetable in d. */
-#define ARM_LPAE_BLOCK_SIZE(l,d) \
- (1ULL << (ilog2(sizeof(arm_lpae_iopte)) + \
- ((ARM_LPAE_MAX_LEVELS - (l)) * (d)->bits_per_level)))
+#define ARM_LPAE_BLOCK_SIZE(l,d) (1ULL << ARM_LPAE_LVL_SHIFT(l,d))
/* Page table bits */
#define ARM_LPAE_PTE_TYPE_SHIFT 0
@@ -175,8 +174,7 @@ struct arm_lpae_io_pgtable {
int pgd_bits;
int start_level;
- unsigned long pg_shift;
- unsigned long bits_per_level;
+ int bits_per_level;
void *pgd;
};
@@ -206,7 +204,7 @@ static phys_addr_t iopte_to_paddr(arm_lpae_iopte pte,
{
u64 paddr = pte & ARM_LPAE_PTE_ADDR_MASK;
- if (data->pg_shift < 16)
+ if (data->bits_per_level < 13) /* i.e. 64K granule */
return paddr;
/* Rotate the packed high-order bits back to the top */
@@ -742,9 +740,8 @@ static void arm_lpae_restrict_pgsizes(struct io_pgtable_cfg
*cfg)
static struct arm_lpae_io_pgtable *
arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
{
- unsigned long va_bits;
struct arm_lpae_io_pgtable *data;
- int levels;
+ int levels, va_bits, pg_shift;
arm_lpae_restrict_pgsizes(cfg);
@@ -766,10 +763,10 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
if (!data)
return NULL;
- data->pg_shift = __ffs(cfg->pgsize_bitmap);
- data->bits_per_level = data->pg_shift - ilog2(sizeof(arm_lpae_iopte));
+ pg_shift = __ffs(cfg->pgsize_bitmap);
+ data->bits_per_level = pg_shift - ilog2(sizeof(arm_lpae_iopte));
- va_bits = cfg->ias - data->pg_shift;
+ va_bits = cfg->ias - pg_shift;
levels = DIV_ROUND_UP(va_bits, data->bits_per_level);
data->start_level = ARM_LPAE_MAX_LEVELS - levels;
@@ -1138,9 +1135,9 @@ static void __init arm_lpae_dump_ops(struct
io_pgtable_ops *ops)
pr_err("cfg: pgsize_bitmap 0x%lx, ias %u-bit\n",
cfg->pgsize_bitmap, cfg->ias);
- pr_err("data: %d levels, 0x%zx pgd_size, %lu pg_shift, %lu
bits_per_level, pgd @ %p\n",
+ pr_err("data: %d levels, 0x%zx pgd_size, %u pg_shift, %u
bits_per_level, pgd @ %p\n",
ARM_LPAE_MAX_LEVELS - data->start_level,
ARM_LPAE_PGD_SIZE(data),
- data->pg_shift, data->bits_per_level, data->pgd);
+ ilog2(ARM_LPAE_GRANULE(data)), data->bits_per_level, data->pgd);
}
#define __FAIL(ops, i) ({ \
--
2.21.0.dirty
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