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 <jcrouse@xxxxxxxxxxxxxx> --- drivers/iommu/arm-smmu-impl.c | 3 ++ drivers/iommu/arm-smmu-qcom.c | 83 ++++++++++++++++++++++++++++++++++- drivers/iommu/arm-smmu.h | 1 + 3 files changed, 85 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/arm-smmu-impl.c b/drivers/iommu/arm-smmu-impl.c index b71b14685cc9..3bb1ef4e85f7 100644 --- a/drivers/iommu/arm-smmu-impl.c +++ b/drivers/iommu/arm-smmu-impl.c @@ -176,5 +176,8 @@ struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu) of_device_is_compatible(np, "qcom,sc7180-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); + return smmu; } diff --git a/drivers/iommu/arm-smmu-qcom.c b/drivers/iommu/arm-smmu-qcom.c index be4318044f96..b9a5c5369e86 100644 --- a/drivers/iommu/arm-smmu-qcom.c +++ b/drivers/iommu/arm-smmu-qcom.c @@ -12,6 +12,67 @@ 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; +} + +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)) { + if (start > 0 || test_bit(0, smmu->context_map)) + return -ENOSPC; + + set_bit(0, smmu->context_map); + return 0; + } + + 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 +126,15 @@ 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, +}; + +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 +144,18 @@ 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); +} diff --git a/drivers/iommu/arm-smmu.h b/drivers/iommu/arm-smmu.h index d10d745a0290..9f81c1fffe1e 100644 --- a/drivers/iommu/arm-smmu.h +++ b/drivers/iommu/arm-smmu.h @@ -491,6 +491,7 @@ static inline void arm_smmu_writeq(struct arm_smmu_device *smmu, int page, struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu); struct arm_smmu_device *qcom_smmu_impl_init(struct arm_smmu_device *smmu); +struct arm_smmu_device *qcom_adreno_smmu_impl_init(struct arm_smmu_device *smmu); int arm_mmu500_reset(struct arm_smmu_device *smmu); -- 2.25.1