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

Tirumalesh Chalamarla
2016-02-24T21:13:53Z

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 address these issuee by supplying asid and vmid
while calculating ASID and VMID for Thunder SMMUv2.

NOTE: resending with commit message fix.

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@caviumnetworks.com>
Signed-off-by: Akula Geethasowjanya <Geethasowjanya.Akula@caviumnetworks.com>
---
.../devicetree/bindings/iommu/arm,smmu.txt | 1 +
drivers/iommu/arm-smmu.c | 48 +++++++++++++++++-----
2 files changed, 38 insertions(+), 11 deletions(-)

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..c704f88 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -326,6 +326,12 @@ struct arm_smmu_device {

struct list_head list;
struct rb_root masters;
+ /*
+ *The following fields are specific to Cavium, Thunder
+ */
+ u32 cavium_smmu_id;
+ u32 cavium_id_base;
+
};

struct arm_smmu_cfg {
@@ -335,8 +341,8 @@ 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 +370,8 @@ struct arm_smmu_option_prop {
const char *prop;
};

+static int cavium_smmu_count;
+
static struct arm_smmu_option_prop arm_smmu_options[] = {
{ ARM_SMMU_OPT_SECURE_CFG_ACCESS, "calxeda,smmu-secure-config-access" },
{ 0, NULL},
@@ -575,11 +583,11 @@ 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 +609,7 @@ 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 +617,7 @@ 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 +637,7 @@ 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 +746,7 @@ static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain,
#endif
/* if 16bit VMID supported set VMID 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 +765,7 @@ 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)) {
/*16 bit VMID is not supported set 8 bit VMID here */
- 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 +773,11 @@ 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 +1725,7 @@ 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);
@@ -1827,6 +1836,23 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
}
}

+ /*
+ * 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 (!strcasecmp(of_id->compatible, "cavium,smmu-v2")) {
+ /* VMID16 must be present on Cavium SMMUv2*/
+ if (!(smmu->features & ARM_SMMU_FEAT_VMID16))
+ goto out_free_irqs;
+ smmu->cavium_smmu_id = cavium_smmu_count;
+ cavium_smmu_count++;
+ smmu->cavium_id_base =
+ (smmu->cavium_smmu_id * ARM_SMMU_MAX_CBS);
+ }
+
INIT_LIST_HEAD(&smmu->list);
spin_lock(&arm_smmu_devices_lock);
list_add(&smmu->list, &arm_smmu_devices);
--
2.1.0