@@ -214,9 +214,12 @@ struct iommufd_viommu *arm_vsmmu_alloc(struct device *dev,
* Must support some way to prevent the VM from bypassing the cache
* because VFIO currently does not do any cache maintenance. canwbs
* indicates the device is fully coherent and no cache maintenance is
- * ever required, even for PCI No-Snoop.
+ * ever required, even for PCI No-Snoop. S2FWB means the S1 can't make
+ * things non-coherent using the memattr, but No-Snoop behavior is not
+ * effected.
*/
- if (!arm_smmu_master_canwbs(master))
+ if (!arm_smmu_master_canwbs(master) &&
+ !(smmu->features & ARM_SMMU_FEAT_S2FWB))
return ERR_PTR(-EOPNOTSUPP);
vsmmu = iommufd_viommu_alloc(ictx, struct arm_vsmmu, core,
@@ -1046,7 +1046,8 @@ void arm_smmu_get_ste_used(const __le64 *ent, __le64 *used_bits)
/* S2 translates */
if (cfg & BIT(1)) {
used_bits[1] |=
- cpu_to_le64(STRTAB_STE_1_EATS | STRTAB_STE_1_SHCFG);
+ cpu_to_le64(STRTAB_STE_1_S2FWB | STRTAB_STE_1_EATS |
+ STRTAB_STE_1_SHCFG);
used_bits[2] |=
cpu_to_le64(STRTAB_STE_2_S2VMID | STRTAB_STE_2_VTCR |
STRTAB_STE_2_S2AA64 | STRTAB_STE_2_S2ENDI |
@@ -1654,6 +1655,8 @@ void arm_smmu_make_s2_domain_ste(struct arm_smmu_ste *target,
FIELD_PREP(STRTAB_STE_1_EATS,
ats_enabled ? STRTAB_STE_1_EATS_TRANS : 0));
+ if (pgtbl_cfg->quirks & IO_PGTABLE_QUIRK_ARM_S2FWB)
+ target->data[1] |= cpu_to_le64(STRTAB_STE_1_S2FWB);
if (smmu->features & ARM_SMMU_FEAT_ATTR_TYPES_OVR)
target->data[1] |= cpu_to_le64(FIELD_PREP(STRTAB_STE_1_SHCFG,
STRTAB_STE_1_SHCFG_INCOMING));
@@ -2472,6 +2475,9 @@ static int arm_smmu_domain_finalise(struct arm_smmu_domain *smmu_domain,
pgtbl_cfg.oas = smmu->oas;
fmt = ARM_64_LPAE_S2;
finalise_stage_fn = arm_smmu_domain_finalise_s2;
+ if ((smmu->features & ARM_SMMU_FEAT_S2FWB) &&
+ (flags & IOMMU_HWPT_ALLOC_NEST_PARENT))
+ pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_ARM_S2FWB;
break;
default:
return -EINVAL;
@@ -58,6 +58,7 @@ struct arm_smmu_device;
#define IDR1_SIDSIZE GENMASK(5, 0)
#define ARM_SMMU_IDR3 0xc
+#define IDR3_FWB (1 << 8)
#define IDR3_RIL (1 << 10)
#define ARM_SMMU_IDR5 0x14
@@ -265,6 +266,7 @@ static inline u32 arm_smmu_strtab_l2_idx(u32 sid)
#define STRTAB_STE_1_S1COR GENMASK_ULL(5, 4)
#define STRTAB_STE_1_S1CSH GENMASK_ULL(7, 6)
+#define STRTAB_STE_1_S2FWB (1UL << 25)
#define STRTAB_STE_1_S1STALLD (1UL << 27)
#define STRTAB_STE_1_EATS GENMASK_ULL(29, 28)
@@ -740,6 +742,7 @@ struct arm_smmu_device {
#define ARM_SMMU_FEAT_ATTR_TYPES_OVR (1 << 20)
#define ARM_SMMU_FEAT_HA (1 << 21)
#define ARM_SMMU_FEAT_HD (1 << 22)
+#define ARM_SMMU_FEAT_S2FWB (1 << 23)
u32 features;
#define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0)
@@ -106,6 +106,18 @@
#define ARM_LPAE_PTE_HAP_FAULT (((arm_lpae_iopte)0) << 6)
#define ARM_LPAE_PTE_HAP_READ (((arm_lpae_iopte)1) << 6)
#define ARM_LPAE_PTE_HAP_WRITE (((arm_lpae_iopte)2) << 6)
+/*
+ * For !FWB these code to:
+ * 1111 = Normal outer write back cachable / Inner Write Back Cachable
+ * Permit S1 to override
+ * 0101 = Normal Non-cachable / Inner Non-cachable
+ * 0001 = Device / Device-nGnRE
+ * For S2FWB these code:
+ * 0110 Force Normal Write Back
+ * 0101 Normal* is forced Normal-NC, Device unchanged
+ * 0001 Force Device-nGnRE
+ */
+#define ARM_LPAE_PTE_MEMATTR_FWB_WB (((arm_lpae_iopte)0x6) << 2)
#define ARM_LPAE_PTE_MEMATTR_OIWB (((arm_lpae_iopte)0xf) << 2)
#define ARM_LPAE_PTE_MEMATTR_NC (((arm_lpae_iopte)0x5) << 2)
#define ARM_LPAE_PTE_MEMATTR_DEV (((arm_lpae_iopte)0x1) << 2)
@@ -458,12 +470,16 @@ static arm_lpae_iopte arm_lpae_prot_to_pte(struct arm_lpae_io_pgtable *data,
*/
if (data->iop.fmt == ARM_64_LPAE_S2 ||
data->iop.fmt == ARM_32_LPAE_S2) {
- if (prot & IOMMU_MMIO)
+ if (prot & IOMMU_MMIO) {
pte |= ARM_LPAE_PTE_MEMATTR_DEV;
- else if (prot & IOMMU_CACHE)
- pte |= ARM_LPAE_PTE_MEMATTR_OIWB;
- else
+ } else if (prot & IOMMU_CACHE) {
+ if (data->iop.cfg.quirks & IO_PGTABLE_QUIRK_ARM_S2FWB)
+ pte |= ARM_LPAE_PTE_MEMATTR_FWB_WB;
+ else
+ 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
@@ -1035,8 +1051,7 @@ arm_64_lpae_alloc_pgtable_s2(struct io_pgtable_cfg *cfg, void *cookie)
struct arm_lpae_io_pgtable *data;
typeof(&cfg->arm_lpae_s2_cfg.vtcr) vtcr = &cfg->arm_lpae_s2_cfg.vtcr;
- /* The NS quirk doesn't apply at stage 2 */
- if (cfg->quirks)
+ if (cfg->quirks & ~(IO_PGTABLE_QUIRK_ARM_S2FWB))
return NULL;
data = arm_lpae_alloc_pgtable(cfg);
@@ -87,6 +87,7 @@ struct io_pgtable_cfg {
* attributes set in the TCR for a non-coherent page-table walker.
*
* IO_PGTABLE_QUIRK_ARM_HD: Enables dirty tracking in stage 1 pagetable.
+ * IO_PGTABLE_QUIRK_ARM_S2FWB: Use the FWB format for the MemAttrs bits
*/
#define IO_PGTABLE_QUIRK_ARM_NS BIT(0)
#define IO_PGTABLE_QUIRK_NO_PERMS BIT(1)
@@ -95,6 +96,7 @@ struct io_pgtable_cfg {
#define IO_PGTABLE_QUIRK_ARM_TTBR1 BIT(5)
#define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA BIT(6)
#define IO_PGTABLE_QUIRK_ARM_HD BIT(7)
+ #define IO_PGTABLE_QUIRK_ARM_S2FWB BIT(8)
unsigned long quirks;
unsigned long pgsize_bitmap;
unsigned int ias;