From: AngeloGioacchino Del Regno <kholk11@xxxxxxxxx> Some IOMMUs associated with some TZ firmwares may support switching to the AArch64 pagetable format by sending a "set pagetable format" scm command indicating the IOMMU secure ID and the context number to switch. Add a DT property "qcom,use-aarch64-pagetables" for this driver to send this command to the secure world and to switch the pagetable format to benefit of the ARM64 IOMMU pagetables, where possible. Note that, even though the command should be valid to switch each context, the property is made global because: 1. It doesn't make too much sense to switch only one or two context(s) to AA64 instead of just the entire thing 2. Some IOMMUs will go crazy and produce spectacular results when trying to mix up the pagetables on a per-context basis. Signed-off-by: AngeloGioacchino Del Regno <kholk11@xxxxxxxxx> --- .../devicetree/bindings/iommu/qcom,iommu.txt | 2 + drivers/iommu/qcom_iommu.c | 55 +++++++++++++++---- 2 files changed, 47 insertions(+), 10 deletions(-) diff --git a/Documentation/devicetree/bindings/iommu/qcom,iommu.txt b/Documentation/devicetree/bindings/iommu/qcom,iommu.txt index ba0b77889f02..72ae0595efff 100644 --- a/Documentation/devicetree/bindings/iommu/qcom,iommu.txt +++ b/Documentation/devicetree/bindings/iommu/qcom,iommu.txt @@ -47,6 +47,8 @@ to non-secure vs secure interrupt line. secure lines. (Ie. if the iommu contains secure context banks) - qcom,ctx-num : The number associated to the context bank +- qcom,use-aarch64-pagetables : Switch to AArch64 pagetable format on all + contexts declared in this IOMMU ** Examples: diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c index 2f31da2e7add..233ef496af27 100644 --- a/drivers/iommu/qcom_iommu.c +++ b/drivers/iommu/qcom_iommu.c @@ -48,6 +48,7 @@ struct qcom_iommu_dev { void __iomem *local_base; u32 sec_id; u8 num_ctxs; + bool use_aarch64_pt; struct qcom_iommu_ctx *ctxs[0]; /* indexed by asid-1 */ }; @@ -153,11 +154,17 @@ static void qcom_iommu_tlb_inv_range_nosync(unsigned long iova, size_t size, reg = leaf ? ARM_SMMU_CB_S1_TLBIVAL : ARM_SMMU_CB_S1_TLBIVA; for (i = 0; i < fwspec->num_ids; i++) { + struct qcom_iommu_dev *qcom_iommu = to_iommu(fwspec); struct qcom_iommu_ctx *ctx = to_ctx(fwspec, fwspec->ids[i]); size_t s = size; - iova &= ~12UL; - iova |= ctx->asid; + if (qcom_iommu->use_aarch64_pt) { + iova >>= 12; + iova |= (u64)ctx->asid << 48; + } else { + iova &= ~12UL; + iova |= ctx->asid; + } do { iommu_writel(ctx, reg, iova); iova += granule; @@ -222,6 +229,8 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain, struct qcom_iommu_domain *qcom_domain = to_qcom_iommu_domain(domain); struct io_pgtable_ops *pgtbl_ops; struct io_pgtable_cfg pgtbl_cfg; + enum io_pgtable_fmt pgtbl_fmt; + unsigned long ias, oas; int i, ret = 0; u32 reg; @@ -229,16 +238,25 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain, if (qcom_domain->iommu) goto out_unlock; + if (qcom_iommu->use_aarch64_pt) { + pgtbl_fmt = ARM_64_LPAE_S1; + ias = oas = 48; + } else { + pgtbl_fmt = ARM_32_LPAE_S1; + ias = 32; + oas = 40; + } + pgtbl_cfg = (struct io_pgtable_cfg) { .pgsize_bitmap = qcom_iommu_ops.pgsize_bitmap, - .ias = 32, - .oas = 40, + .ias = ias, + .oas = oas, .tlb = &qcom_gather_ops, .iommu_dev = qcom_iommu->dev, }; qcom_domain->iommu = qcom_iommu; - pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, fwspec); + pgtbl_ops = alloc_io_pgtable_ops(pgtbl_fmt, &pgtbl_cfg, fwspec); if (!pgtbl_ops) { dev_err(qcom_iommu->dev, "failed to allocate pagetable ops\n"); ret = -ENOMEM; @@ -252,6 +270,7 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain, for (i = 0; i < fwspec->num_ids; i++) { struct qcom_iommu_ctx *ctx = to_ctx(fwspec, fwspec->ids[i]); + u32 tcr[2]; if (!ctx->secure_init) { ret = qcom_scm_restore_sec_cfg(qcom_iommu->sec_id, ctx->asid); @@ -264,12 +283,25 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain, qcom_iommu_reset_ctx(ctx); + tcr[0] = pgtbl_cfg.arm_lpae_s1_cfg.tcr; + tcr[1] = pgtbl_cfg.arm_lpae_s1_cfg.tcr >> 32; + tcr[1] |= FIELD_PREP(TCR2_SEP, TCR2_SEP_UPSTREAM); + + if (qcom_iommu->use_aarch64_pt) { + /* This shall not fail, or spectacular things happen */ + if (qcom_scm_iommu_set_pt_format(qcom_iommu->sec_id, + ctx->asid, 1)) { + dev_warn(qcom_iommu->dev, + "Cannot set AArch64 pt format\n"); + goto out_clear_iommu; + } + + tcr[1] |= TCR2_AS; + } + /* TCR */ - iommu_writel(ctx, ARM_SMMU_CB_TCR2, - (pgtbl_cfg.arm_lpae_s1_cfg.tcr >> 32) | - FIELD_PREP(TCR2_SEP, TCR2_SEP_UPSTREAM)); - iommu_writel(ctx, ARM_SMMU_CB_TCR, - pgtbl_cfg.arm_lpae_s1_cfg.tcr); + iommu_writel(ctx, ARM_SMMU_CB_TCR2, tcr[1]); + iommu_writel(ctx, ARM_SMMU_CB_TCR, tcr[0]); /* TTBRs */ iommu_writeq(ctx, ARM_SMMU_CB_TTBR0, @@ -844,6 +876,9 @@ static int qcom_iommu_device_probe(struct platform_device *pdev) return -ENODEV; } + if (of_property_read_bool(dev->of_node, "qcom,use-aarch64-pagetables")) + qcom_iommu->use_aarch64_pt = true; + if (qcom_iommu_has_secure_context(qcom_iommu)) { ret = qcom_iommu_sec_ptbl_init(dev); if (ret) { -- 2.21.0