Add a special implementation for the SMMU attached to most Adreno GPU target triggered from the qcom,adreno-smmu compatible string.
The new Adreno SMMU implementation will enable split pagetables (TTBR1) for the domain attached to the GPU device (SID 0) and hard code it context bank 0 so the GPU hardware can implement per-instance pagetables. Signed-off-by: Jordan Crouse <jcro...@codeaurora.org> --- drivers/iommu/arm/arm-smmu/arm-smmu-impl.c | 3 + drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 156 ++++++++++++++++++++- 2 files changed, 157 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c b/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c index 88f17cc33023..d199b4bff15d 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-impl.c @@ -223,6 +223,9 @@ struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu) of_device_is_compatible(np, "qcom,sm8250-smmu-500")) return qcom_smmu_impl_init(smmu); + if (of_device_is_compatible(smmu->dev->of_node, "qcom,adreno-smmu")) + return qcom_adreno_smmu_impl_init(smmu); + if (of_device_is_compatible(np, "marvell,ap806-smmu-500")) smmu->impl = &mrvl_mmu500_impl; diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c index be4318044f96..3be10145bf57 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c @@ -12,6 +12,138 @@ struct qcom_smmu { struct arm_smmu_device smmu; }; +#define QCOM_ADRENO_SMMU_GPU_SID 0 + +static bool qcom_adreno_smmu_is_gpu_device(struct device *dev) +{ + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); + struct arm_smmu_master_cfg *cfg = dev_iommu_priv_get(dev); + int idx, i; + + /* + * The GPU will always use SID 0 so that is a handy way to uniquely + * identify it and configure it for per-instance pagetables + */ + for_each_cfg_sme(cfg, fwspec, i, idx) { + u16 sid = FIELD_GET(ARM_SMMU_SMR_ID, fwspec->ids[i]); + + if (sid == QCOM_ADRENO_SMMU_GPU_SID) + return true; + } + + return false; +} + +/* + * Local implementation to configure TTBR0 with the specified pagetable config. + * The GPU driver will call this to enable TTBR0 when per-instance pagetables + * are active + */ +static int qcom_adreno_smmu_set_pgtable_cfg(struct arm_smmu_domain *smmu_domain, + struct io_pgtable_cfg *pgtbl_cfg) +{ + struct io_pgtable *pgtable = io_pgtable_ops_to_pgtable(smmu_domain->pgtbl_ops); + struct arm_smmu_cfg *cfg = &smmu_domain->cfg; + struct arm_smmu_cb *cb = &smmu_domain->smmu->cbs[cfg->cbndx]; + + /* The domain must have split pagetables already enabled */ + if (cb->tcr[0] & ARM_SMMU_TCR_EPD1) + return -EINVAL; + + /* If the pagetable config is NULL, disable TTBR0 */ + if (!pgtbl_cfg) { + /* Do nothing if it is already disabled */ + if ((cb->tcr[0] & ARM_SMMU_TCR_EPD0)) + return -EINVAL; + + /* Set TCR to the original configuration */ + cb->tcr[0] = arm_smmu_lpae_tcr(&pgtable->cfg); + cb->ttbr[0] = FIELD_PREP(ARM_SMMU_TTBRn_ASID, cb->cfg->asid); + } else { + u32 tcr = cb->tcr[0]; + + /* Don't call this again if TTBR0 is already enabled */ + if (!(cb->tcr[0] & ARM_SMMU_TCR_EPD0)) + return -EINVAL; + + tcr |= arm_smmu_lpae_tcr(pgtbl_cfg); + tcr &= ~(ARM_SMMU_TCR_EPD0 | ARM_SMMU_TCR_EPD1); + + cb->tcr[0] = tcr; + cb->ttbr[0] = pgtbl_cfg->arm_lpae_s1_cfg.ttbr; + cb->ttbr[0] |= FIELD_PREP(ARM_SMMU_TTBRn_ASID, cb->cfg->asid); + } + + arm_smmu_write_context_bank(smmu_domain->smmu, cb->cfg->cbndx); + return 0; +} + +static int qcom_adreno_smmu_domain_get_attr(struct arm_smmu_domain *smmu_domain, + enum iommu_attr attr, void *data) +{ + struct io_pgtable *pgtable; + struct io_pgtable_cfg *dest = data; + + if (attr == DOMAIN_ATTR_PGTABLE_CFG) { + + if (!smmu_domain->pgtbl_ops) + return -ENODEV; + + pgtable = io_pgtable_ops_to_pgtable(smmu_domain->pgtbl_ops); + memcpy(dest, &pgtable->cfg, sizeof(*dest)); + return 0; + } + + return -ENODEV; +} + +static int qcom_adreno_smmu_domain_set_attr(struct arm_smmu_domain *smmu_domain, + enum iommu_attr attr, void *data) +{ + if (attr == DOMAIN_ATTR_PGTABLE_CFG) + return qcom_adreno_smmu_set_pgtable_cfg(smmu_domain, data); + + return -ENODEV; +} + +static int qcom_adreno_smmu_alloc_context_bank(struct arm_smmu_domain *smmu_domain, + struct device *dev, int start, int count) +{ + struct arm_smmu_device *smmu = smmu_domain->smmu; + + /* + * Assign context bank 0 to the GPU device so the GPU hardware can + * switch pagetables + */ + if (qcom_adreno_smmu_is_gpu_device(dev)) { + start = 0; + count = 1; + } else { + start = 1; + } + + return __arm_smmu_alloc_bitmap(smmu->context_map, start, count); +} + +static int qcom_adreno_smmu_init_context(struct arm_smmu_domain *smmu_domain, + struct io_pgtable_cfg *pgtbl_cfg, struct device *dev) +{ + /* Only enable split pagetables for the GPU device (SID 0) */ + if (!qcom_adreno_smmu_is_gpu_device(dev)) + return 0; + + /* + * All targets that use the qcom,adreno-smmu compatible string *should* + * be AARCH64 stage 1 but double check because the arm-smmu code assumes + * that is the case when the TTBR1 quirk is enabled + */ + if ((smmu_domain->stage == ARM_SMMU_DOMAIN_S1) && + (smmu_domain->cfg.fmt == ARM_SMMU_CTX_FMT_AARCH64)) + pgtbl_cfg->quirks |= IO_PGTABLE_QUIRK_ARM_TTBR1; + + return 0; +} + static const struct of_device_id qcom_smmu_client_of_match[] __maybe_unused = { { .compatible = "qcom,adreno" }, { .compatible = "qcom,mdp4" }, @@ -65,7 +197,17 @@ static const struct arm_smmu_impl qcom_smmu_impl = { .reset = qcom_smmu500_reset, }; -struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu) +static const struct arm_smmu_impl qcom_adreno_smmu_impl = { + .init_context = qcom_adreno_smmu_init_context, + .def_domain_type = qcom_smmu_def_domain_type, + .reset = qcom_smmu500_reset, + .alloc_context_bank = qcom_adreno_smmu_alloc_context_bank, + .domain_set_attr = qcom_adreno_smmu_domain_set_attr, + .domain_get_attr = qcom_adreno_smmu_domain_get_attr, +}; + +static struct arm_smmu_device *qcom_smmu_create(struct arm_smmu_device *smmu, + const struct arm_smmu_impl *impl) { struct qcom_smmu *qsmmu; @@ -75,8 +217,18 @@ struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu) qsmmu->smmu = *smmu; - qsmmu->smmu.impl = &qcom_smmu_impl; + qsmmu->smmu.impl = impl; devm_kfree(smmu->dev, smmu); return &qsmmu->smmu; } + +struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu) +{ + return qcom_smmu_create(smmu, &qcom_smmu_impl); +} + +struct arm_smmu_device *qcom_adreno_smmu_impl_init(struct arm_smmu_device *smmu) +{ + return qcom_smmu_create(smmu, &qcom_adreno_smmu_impl); +} -- 2.25.1