iommu/arm-smmu: don't bother truncating the s1 output size to VA_BITS
In order for nested translation to work correctly, we need to ensure
that the maximum output address size from stage-1 is <= the maximum
supported input address size to stage-2. The latter is currently defined
by VA_BITS, since we make use of the CPU page table functions for
allocating out tables and so the driver currently enforces this
restriction by truncating the stage-1 output size during probe.
In reality, this doesn't make a lot of sense; the guest OS is responsible
for managing the stage-1 page tables, so we actually just need to ensure
that the ID registers of the virtual SMMU interface only advertise the
supported stage-2 input size.
This patch fixes the problem by treating the stage-1 and stage-2 input
address sizes separately.
Reported-by: Tirumalesh Chalamarla <tchalamarla@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 482cc9e..27fd3d7 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -24,7 +24,7 @@
* - v7/v8 long-descriptor format
* - Non-secure access to the SMMU
* - 4k and 64k pages, with contiguous pte hints.
- * - Up to 42-bit addressing (dependent on VA_BITS)
+ * - Up to 48-bit addressing (dependent on VA_BITS)
* - Context fault reporting
*/
@@ -375,8 +375,9 @@
u32 num_mapping_groups;
DECLARE_BITMAP(smr_map, ARM_SMMU_MAX_SMRS);
- unsigned long input_size;
+ unsigned long s1_input_size;
unsigned long s1_output_size;
+ unsigned long s2_input_size;
unsigned long s2_output_size;
u32 num_global_irqs;
@@ -762,7 +763,7 @@
gr1_base + ARM_SMMU_GR1_CBA2R(cfg->cbndx));
/* TTBCR2 */
- switch (smmu->input_size) {
+ switch (smmu->s1_input_size) {
case 32:
reg = (TTBCR2_ADDR_32 << TTBCR2_SEP_SHIFT);
break;
@@ -831,7 +832,7 @@
reg = TTBCR_TG0_64K;
if (!stage1) {
- reg |= (64 - smmu->s1_output_size) << TTBCR_T0SZ_SHIFT;
+ reg |= (64 - smmu->s2_input_size) << TTBCR_T0SZ_SHIFT;
switch (smmu->s2_output_size) {
case 32:
@@ -854,7 +855,7 @@
break;
}
} else {
- reg |= (64 - smmu->input_size) << TTBCR_T0SZ_SHIFT;
+ reg |= (64 - smmu->s1_input_size) << TTBCR_T0SZ_SHIFT;
}
} else {
reg = 0;
@@ -1454,9 +1455,11 @@
if (cfg->cbar == CBAR_TYPE_S2_TRANS) {
stage = 2;
+ input_mask = (1ULL << smmu->s2_input_size) - 1;
output_mask = (1ULL << smmu->s2_output_size) - 1;
} else {
stage = 1;
+ input_mask = (1ULL << smmu->s1_input_size) - 1;
output_mask = (1ULL << smmu->s1_output_size) - 1;
}
@@ -1466,7 +1469,6 @@
if (size & ~PAGE_MASK)
return -EINVAL;
- input_mask = (1ULL << smmu->input_size) - 1;
if ((phys_addr_t)iova & ~input_mask)
return -ERANGE;
@@ -1838,28 +1840,21 @@
/* ID2 */
id = readl_relaxed(gr0_base + ARM_SMMU_GR0_ID2);
size = arm_smmu_id_size_to_bits((id >> ID2_IAS_SHIFT) & ID2_IAS_MASK);
+ smmu->s1_output_size = min_t(unsigned long, PHYS_MASK_SHIFT, size);
- /*
- * Stage-1 output limited by stage-2 input size due to pgd
- * allocation (PTRS_PER_PGD).
- */
- if (smmu->features & ARM_SMMU_FEAT_TRANS_NESTED) {
+ /* Stage-2 input size limited due to pgd allocation (PTRS_PER_PGD) */
#ifdef CONFIG_64BIT
- smmu->s1_output_size = min_t(unsigned long, VA_BITS, size);
+ smmu->s2_input_size = min_t(unsigned long, VA_BITS, size);
#else
- smmu->s1_output_size = min(32UL, size);
+ smmu->s2_input_size = min(32UL, size);
#endif
- } else {
- smmu->s1_output_size = min_t(unsigned long, PHYS_MASK_SHIFT,
- size);
- }
/* The stage-2 output mask is also applied for bypass */
size = arm_smmu_id_size_to_bits((id >> ID2_OAS_SHIFT) & ID2_OAS_MASK);
smmu->s2_output_size = min_t(unsigned long, PHYS_MASK_SHIFT, size);
if (smmu->version == 1) {
- smmu->input_size = 32;
+ smmu->s1_input_size = 32;
} else {
#ifdef CONFIG_64BIT
size = (id >> ID2_UBS_SHIFT) & ID2_UBS_MASK;
@@ -1867,7 +1862,7 @@
#else
size = 32;
#endif
- smmu->input_size = size;
+ smmu->s1_input_size = size;
if ((PAGE_SIZE == SZ_4K && !(id & ID2_PTFS_4K)) ||
(PAGE_SIZE == SZ_64K && !(id & ID2_PTFS_64K)) ||
@@ -1878,10 +1873,14 @@
}
}
- dev_notice(smmu->dev,
- "\t%lu-bit VA, %lu-bit IPA, %lu-bit PA\n",
- smmu->input_size, smmu->s1_output_size,
- smmu->s2_output_size);
+ if (smmu->features & ARM_SMMU_FEAT_TRANS_S1)
+ dev_notice(smmu->dev, "\tStage-1: %lu-bit VA -> %lu-bit IPA\n",
+ smmu->s1_input_size, smmu->s1_output_size);
+
+ if (smmu->features & ARM_SMMU_FEAT_TRANS_S2)
+ dev_notice(smmu->dev, "\tStage-2: %lu-bit IPA -> %lu-bit PA\n",
+ smmu->s2_input_size, smmu->s2_output_size);
+
return 0;
}