[PATCH RFC 16/19] iommu/arm-smmu-v3: Enable HTTU for stage1 with io-pgtable mapping

Joao Martins
2022-04-28T21:12:19Z

From: Kunkun Jiang <jiangkunkun@huawei.com>

As nested mode is not upstreamed now, we just aim to support dirty
log tracking for stage1 with io-pgtable mapping (means not support
SVA mapping). If HTTU is supported, we enable HA/HD bits in the SMMU
CD and transfer ARM_HD quirk to io-pgtable.

We additionally filter out HD|HA if not supportted. The CD.HD bit
is not particularly useful unless we toggle the DBM bit in the PTE
entries.

Co-developed-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com>
Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com>
[joaomart:Convey HD|HA bits over to the context descriptor
and update commit message]
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 +++++++++++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 3 +++
include/linux/io-pgtable.h | 1 +
3 files changed, 15 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 1ca72fcca930..5f728f8f20a2 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -1077,10 +1077,18 @@ int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, int ssid,
* this substream's traffic
*/
} else { /* (1) and (2) */
+ struct arm_smmu_device *smmu = smmu_domain->smmu;
+ u64 tcr = cd->tcr;
+
cdptr[1] = cpu_to_le64(cd->ttbr & CTXDESC_CD_1_TTB0_MASK);
cdptr[2] = 0;
cdptr[3] = cpu_to_le64(cd->mair);

+ if (!(smmu->features & ARM_SMMU_FEAT_HD))
+ tcr &= ~CTXDESC_CD_0_TCR_HD;
+ if (!(smmu->features & ARM_SMMU_FEAT_HA))
+ tcr &= ~CTXDESC_CD_0_TCR_HA;
+
/*
* STE is live, and the SMMU might read dwords of this CD in any
* order. Ensure that it observes valid values before reading
@@ -2100,6 +2108,7 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
FIELD_PREP(CTXDESC_CD_0_TCR_ORGN0, tcr->orgn) |
FIELD_PREP(CTXDESC_CD_0_TCR_SH0, tcr->sh) |
FIELD_PREP(CTXDESC_CD_0_TCR_IPS, tcr->ips) |
+ CTXDESC_CD_0_TCR_HA | CTXDESC_CD_0_TCR_HD |
CTXDESC_CD_0_TCR_EPD1 | CTXDESC_CD_0_AA64;
cfg->cd.mair = pgtbl_cfg->arm_lpae_s1_cfg.mair;

@@ -2203,6 +2212,8 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain,
.iommu_dev = smmu->dev,
};

+ if (smmu->features & ARM_SMMU_FEAT_HD)
+ pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_ARM_HD;
if (smmu->features & ARM_SMMU_FEAT_BBML1)
pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_ARM_BBML1;
else if (smmu->features & ARM_SMMU_FEAT_BBML2)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index e15750be1d95..ff32242f2fdb 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -292,6 +292,9 @@
#define CTXDESC_CD_0_TCR_IPS GENMASK_ULL(34, 32)
#define CTXDESC_CD_0_TCR_TBI0 (1ULL << 38)

+#define CTXDESC_CD_0_TCR_HA (1UL << 43)
+#define CTXDESC_CD_0_TCR_HD (1UL << 42)
+
#define CTXDESC_CD_0_AA64 (1UL << 41)
#define CTXDESC_CD_0_S (1UL << 44)
#define CTXDESC_CD_0_R (1UL << 45)
diff --git a/include/linux/io-pgtable.h b/include/linux/io-pgtable.h
index d7626ca67dbf..a11902ae9cf1 100644
--- a/include/linux/io-pgtable.h
+++ b/include/linux/io-pgtable.h
@@ -87,6 +87,7 @@ struct io_pgtable_cfg {
#define IO_PGTABLE_QUIRK_ARM_OUTER_WBWA BIT(6)
#define IO_PGTABLE_QUIRK_ARM_BBML1 BIT(7)
#define IO_PGTABLE_QUIRK_ARM_BBML2 BIT(8)
+ #define IO_PGTABLE_QUIRK_ARM_HD BIT(9)

unsigned long quirks;
unsigned long pgsize_bitmap;
--
2.17.2