[PATCH V4] iommu/arm-smmu-v2: Workaround for ThunderX errata#27704

Chalamarla, Tirumalesh Tirumalesh.Chalamarla at caviumnetworks.com
Thu Mar 24 10:36:39 PDT 2016


Hi Will,

Do you want me to resend it with path version number change?

Thanks,
Tirumalesh.




On 3/4/16, 1:56 PM, "Chalamarla, Tirumalesh" <Tirumalesh.Chalamarla at caviumnetworks.com> wrote:

>Due to Errata#27704 CN88xx SMMUv2,supports  only shared ASID and VMID
>namespaces; specifically within a given node SMMU0 and SMMU1 share,
>as does SMMU2 and SMMU3.
>
>This patch make sure ASID and VMID space is unique across cavium SMMUv2.
>
>changes from V3:
>	- Removed redundent variable.
>	- Used atomic_t for maintaining running total
>
>changes from V2:
>	- removed *_base from DT, and replaced with compatible string
>
>changes from V1:
>	- rebased on top of 16 bit VMID patch
>	- removed redundent options from DT
>	- insted of transform, DT now supplies starting ASID/VMID
>
>Signed-off-by: Tirumalesh Chalamarla <tchalamarla at caviumnetworks.com>
>Signed-off-by: Akula Geethasowjanya <Geethasowjanya.Akula at caviumnetworks.com>
>---
> Documentation/arm64/silicon-errata.txt             |  1 +
> .../devicetree/bindings/iommu/arm,smmu.txt         |  1 +
> drivers/iommu/arm-smmu.c                           | 42 ++++++++++++++++------
> 3 files changed, 33 insertions(+), 11 deletions(-)
>
>diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt
>index 58b71dd..3747a4b 100644
>--- a/Documentation/arm64/silicon-errata.txt
>+++ b/Documentation/arm64/silicon-errata.txt
>@@ -56,3 +56,4 @@ stable kernels.
> |                |                 |                 |                         |
> | Cavium         | ThunderX ITS    | #22375, #24313  | CAVIUM_ERRATUM_22375    |
> | Cavium         | ThunderX GICv3  | #23154          | CAVIUM_ERRATUM_23154    |
>+| Cavium         | ThunderX SMMUv2 | #27704          | N/A		       |
>diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
>index 7180745..19fe6f2 100644
>--- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt
>+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
>@@ -16,6 +16,7 @@ conditions.
>                         "arm,mmu-400"
>                         "arm,mmu-401"
>                         "arm,mmu-500"
>+                        "cavium,smmu-v2"
>
>                   depending on the particular implementation and/or the
>                   version of the architecture implemented.
>diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
>index 247a469..e793b0a 100644
>--- a/drivers/iommu/arm-smmu.c
>+++ b/drivers/iommu/arm-smmu.c
>@@ -326,6 +326,11 @@ struct arm_smmu_device {
>
> 	struct list_head		list;
> 	struct rb_root			masters;
>+	/*
>+	 *The following fields are specific to Cavium, Thunder
>+	 */
>+	u32				cavium_id_base;
>+
> };
>
> struct arm_smmu_cfg {
>@@ -335,8 +340,8 @@ struct arm_smmu_cfg {
> };
> #define INVALID_IRPTNDX			0xff
>
>-#define ARM_SMMU_CB_ASID(cfg)		((cfg)->cbndx)
>-#define ARM_SMMU_CB_VMID(cfg)		((cfg)->cbndx + 1)
>+#define ARM_SMMU_CB_ASID(smmu, cfg) ((u16)(smmu)->cavium_id_base + (cfg)->cbndx)
>+#define ARM_SMMU_CB_VMID(smmu, cfg) ((u16)(smmu)->cavium_id_base + (cfg)->cbndx + 1)
>
> enum arm_smmu_domain_stage {
> 	ARM_SMMU_DOMAIN_S1 = 0,
>@@ -364,6 +369,8 @@ struct arm_smmu_option_prop {
> 	const char *prop;
> };
>
>+static atomic_t cavium_smmu_context_count = ATOMIC_INIT(0);
>+
> static struct arm_smmu_option_prop arm_smmu_options[] = {
> 	{ ARM_SMMU_OPT_SECURE_CFG_ACCESS, "calxeda,smmu-secure-config-access" },
> 	{ 0, NULL},
>@@ -575,11 +582,11 @@ static void arm_smmu_tlb_inv_context(void *cookie)
>
> 	if (stage1) {
> 		base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
>-		writel_relaxed(ARM_SMMU_CB_ASID(cfg),
>+		writel_relaxed(ARM_SMMU_CB_ASID(smmu, cfg),
> 			       base + ARM_SMMU_CB_S1_TLBIASID);
> 	} else {
> 		base = ARM_SMMU_GR0(smmu);
>-		writel_relaxed(ARM_SMMU_CB_VMID(cfg),
>+		writel_relaxed(ARM_SMMU_CB_VMID(smmu, cfg),
> 			       base + ARM_SMMU_GR0_TLBIVMID);
> 	}
>
>@@ -601,7 +608,7 @@ static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
>
> 		if (!IS_ENABLED(CONFIG_64BIT) || smmu->version == ARM_SMMU_V1) {
> 			iova &= ~12UL;
>-			iova |= ARM_SMMU_CB_ASID(cfg);
>+			iova |= ARM_SMMU_CB_ASID(smmu, cfg);
> 			do {
> 				writel_relaxed(iova, reg);
> 				iova += granule;
>@@ -609,7 +616,7 @@ static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
> #ifdef CONFIG_64BIT
> 		} else {
> 			iova >>= 12;
>-			iova |= (u64)ARM_SMMU_CB_ASID(cfg) << 48;
>+			iova |= (u64)ARM_SMMU_CB_ASID(smmu, cfg) << 48;
> 			do {
> 				writeq_relaxed(iova, reg);
> 				iova += granule >> 12;
>@@ -629,7 +636,7 @@ static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
> #endif
> 	} else {
> 		reg = ARM_SMMU_GR0(smmu) + ARM_SMMU_GR0_TLBIVMID;
>-		writel_relaxed(ARM_SMMU_CB_VMID(cfg), reg);
>+		writel_relaxed(ARM_SMMU_CB_VMID(smmu, cfg), reg);
> 	}
> }
>
>@@ -738,7 +745,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain,
> #endif
> 		/* 16-bit VMIDs live in CBA2R */
> 		if (smmu->features & ARM_SMMU_FEAT_VMID16)
>-			reg |= ARM_SMMU_CB_VMID(cfg) << CBA2R_VMID_SHIFT;
>+			reg |= ARM_SMMU_CB_VMID(smmu, cfg) << CBA2R_VMID_SHIFT;
>
> 		writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBA2R(cfg->cbndx));
> 	}
>@@ -757,7 +764,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain,
> 			(CBAR_S1_MEMATTR_WB << CBAR_S1_MEMATTR_SHIFT);
> 	} else if (!(smmu->features & ARM_SMMU_FEAT_VMID16)) {
> 		/* 8-bit VMIDs live in CBAR */
>-		reg |= ARM_SMMU_CB_VMID(cfg) << CBAR_VMID_SHIFT;
>+		reg |= ARM_SMMU_CB_VMID(smmu, cfg) << CBAR_VMID_SHIFT;
> 	}
> 	writel_relaxed(reg, gr1_base + ARM_SMMU_GR1_CBAR(cfg->cbndx));
>
>@@ -765,11 +772,11 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain,
> 	if (stage1) {
> 		reg64 = pgtbl_cfg->arm_lpae_s1_cfg.ttbr[0];
>
>-		reg64 |= ((u64)ARM_SMMU_CB_ASID(cfg)) << TTBRn_ASID_SHIFT;
>+		reg64 |= ((u64)ARM_SMMU_CB_ASID(smmu, cfg)) << TTBRn_ASID_SHIFT;
> 		smmu_writeq(reg64, cb_base + ARM_SMMU_CB_TTBR0);
>
> 		reg64 = pgtbl_cfg->arm_lpae_s1_cfg.ttbr[1];
>-		reg64 |= ((u64)ARM_SMMU_CB_ASID(cfg)) << TTBRn_ASID_SHIFT;
>+		reg64 |= ((u64)ARM_SMMU_CB_ASID(smmu, cfg)) << TTBRn_ASID_SHIFT;
> 		smmu_writeq(reg64, cb_base + ARM_SMMU_CB_TTBR1);
> 	} else {
> 		reg64 = pgtbl_cfg->arm_lpae_s2_cfg.vttbr;
>@@ -1717,6 +1724,7 @@ static const struct of_device_id arm_smmu_of_match[] = {
> 	{ .compatible = "arm,mmu-400", .data = (void *)ARM_SMMU_V1 },
> 	{ .compatible = "arm,mmu-401", .data = (void *)ARM_SMMU_V1 },
> 	{ .compatible = "arm,mmu-500", .data = (void *)ARM_SMMU_V2 },
>+	{ .compatible = "cavium,smmu-v2", .data = (void *)ARM_SMMU_V2 },
> 	{ },
> };
> MODULE_DEVICE_TABLE(of, arm_smmu_of_match);
>@@ -1826,6 +1834,18 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
> 			goto out_free_irqs;
> 		}
> 	}
>+	/*
>+	 * Due to Errata#27704 CN88xx SMMUv2,supports  only shared ASID and VMID
>+	 * namespaces; specifically within a given node SMMU0 and SMMU1 share,
>+	 * as does SMMU2 and SMMU3. see if this is a Cavium SMMU, if so
>+	 * set asid and vmid base such that each SMMU gets unique
>+	 * asid/vmid space.
>+	 */
>+	if (of_device_is_compatible(dev->of_node, "cavium,smmu-v2")) {
>+		smmu->cavium_id_base = atomic_add_return(smmu->num_context_banks,
>+				&cavium_smmu_context_count);
>+		smmu->cavium_id_base -= smmu->num_context_banks;
>+	}
>
> 	INIT_LIST_HEAD(&smmu->list);
> 	spin_lock(&arm_smmu_devices_lock);
>--
>2.1.0
>


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