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iommu/arm-smmu-v3: Add workaround for Cavium ThunderX2 erratum #74

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Cavium ThunderX2 SMMU implementation doesn't support page 1 register space
and PAGE0_REGS_ONLY option is enabled as an errata workaround.
This option when turned on, replaces all page 1 offsets used for
EVTQ_PROD/CONS, PRIQ_PROD/CONS register access with page 0 offsets.

SMMU resource size checks are now based on SMMU option PAGE0_REGS_ONLY,
since resource size can be either 64k/128k.
For this, arm_smmu_device_dt_probe/acpi_probe has been moved before
platform_get_resource call, so that SMMU options are set beforehand.

Signed-off-by: Linu Cherian <linu.cherian@cavium.com>
Signed-off-by: Geetha Sowjanya <geethasowjanya.akula@cavium.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
This commit is contained in:
Linu Cherian 2017-06-22 17:35:37 +05:30 committed by Will Deacon
parent 403e8c7c5b
commit e5b829de05
3 changed files with 57 additions and 18 deletions
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1
Documentation/arm64/silicon-errata.txt
View File

@ -62,6 +62,7 @@ stable kernels.
| Cavium | ThunderX GICv3 | #23154 | CAVIUM_ERRATUM_23154 |
| Cavium | ThunderX Core | #27456 | CAVIUM_ERRATUM_27456 |
| Cavium | ThunderX SMMUv2 | #27704 | N/A |
| Cavium | ThunderX2 SMMUv3| #74 | N/A |
| | | | |
| Freescale/NXP | LS2080A/LS1043A | A-008585 | FSL_ERRATUM_A008585 |
| | | | |

6
Documentation/devicetree/bindings/iommu/arm,smmu-v3.txt
View File

@ -49,6 +49,12 @@ the PCIe specification.
- hisilicon,broken-prefetch-cmd
: Avoid sending CMD_PREFETCH_* commands to the SMMU.
- cavium,cn9900-broken-page1-regspace
: Replaces all page 1 offsets used for EVTQ_PROD/CONS,
PRIQ_PROD/CONS register access with page 0 offsets.
Set for Cavium ThunderX2 silicon that doesn't support
SMMU page1 register space.
** Example
smmu@2b400000 {

68
drivers/iommu/arm-smmu-v3.c
View File

@ -603,6 +603,7 @@ struct arm_smmu_device {
u32 features;
#define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0)
#define ARM_SMMU_OPT_PAGE0_REGS_ONLY (1 << 1)
u32 options;
struct arm_smmu_cmdq cmdq;
@ -668,9 +669,20 @@ struct arm_smmu_option_prop {
static struct arm_smmu_option_prop arm_smmu_options[] = {
{ ARM_SMMU_OPT_SKIP_PREFETCH, "hisilicon,broken-prefetch-cmd" },
{ ARM_SMMU_OPT_PAGE0_REGS_ONLY, "cavium,cn9900-broken-page1-regspace"},
{ 0, NULL},
};
static inline void __iomem *arm_smmu_page1_fixup(unsigned long offset,
struct arm_smmu_device *smmu)
{
if ((offset > SZ_64K) &&
(smmu->options & ARM_SMMU_OPT_PAGE0_REGS_ONLY))
offset -= SZ_64K;
return smmu->base + offset;
}
static struct arm_smmu_domain *to_smmu_domain(struct iommu_domain *dom)
{
return container_of(dom, struct arm_smmu_domain, domain);
@ -1956,8 +1968,8 @@ static int arm_smmu_init_one_queue(struct arm_smmu_device *smmu,
return -ENOMEM;
}
q->prod_reg = smmu->base + prod_off;
q->cons_reg = smmu->base + cons_off;
q->prod_reg = arm_smmu_page1_fixup(prod_off, smmu);
q->cons_reg = arm_smmu_page1_fixup(cons_off, smmu);
q->ent_dwords = dwords;
q->q_base = Q_BASE_RWA;
@ -2358,8 +2370,10 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
/* Event queue */
writeq_relaxed(smmu->evtq.q.q_base, smmu->base + ARM_SMMU_EVTQ_BASE);
writel_relaxed(smmu->evtq.q.prod, smmu->base + ARM_SMMU_EVTQ_PROD);
writel_relaxed(smmu->evtq.q.cons, smmu->base + ARM_SMMU_EVTQ_CONS);
writel_relaxed(smmu->evtq.q.prod,
arm_smmu_page1_fixup(ARM_SMMU_EVTQ_PROD, smmu));
writel_relaxed(smmu->evtq.q.cons,
arm_smmu_page1_fixup(ARM_SMMU_EVTQ_CONS, smmu));
enables |= CR0_EVTQEN;
ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
@ -2374,9 +2388,9 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
writeq_relaxed(smmu->priq.q.q_base,
smmu->base + ARM_SMMU_PRIQ_BASE);
writel_relaxed(smmu->priq.q.prod,
smmu->base + ARM_SMMU_PRIQ_PROD);
arm_smmu_page1_fixup(ARM_SMMU_PRIQ_PROD, smmu));
writel_relaxed(smmu->priq.q.cons,
smmu->base + ARM_SMMU_PRIQ_CONS);
arm_smmu_page1_fixup(ARM_SMMU_PRIQ_CONS, smmu));
enables |= CR0_PRIQEN;
ret = arm_smmu_write_reg_sync(smmu, enables, ARM_SMMU_CR0,
@ -2600,6 +2614,14 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
}
#ifdef CONFIG_ACPI
static void acpi_smmu_get_options(u32 model, struct arm_smmu_device *smmu)
{
if (model == ACPI_IORT_SMMU_V3_CAVIUM_CN99XX)
smmu->options |= ARM_SMMU_OPT_PAGE0_REGS_ONLY;
dev_notice(smmu->dev, "option mask 0x%x\n", smmu->options);
}
static int arm_smmu_device_acpi_probe(struct platform_device *pdev,
struct arm_smmu_device *smmu)
{
@ -2612,6 +2634,8 @@ static int arm_smmu_device_acpi_probe(struct platform_device *pdev,
/* Retrieve SMMUv3 specific data */
iort_smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
acpi_smmu_get_options(iort_smmu->model, smmu);
if (iort_smmu->flags & ACPI_IORT_SMMU_V3_COHACC_OVERRIDE)
smmu->features |= ARM_SMMU_FEAT_COHERENCY;
@ -2647,6 +2671,14 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev,
return ret;
}
static unsigned long arm_smmu_resource_size(struct arm_smmu_device *smmu)
{
if (smmu->options & ARM_SMMU_OPT_PAGE0_REGS_ONLY)
return SZ_64K;
else
return SZ_128K;
}
static int arm_smmu_device_probe(struct platform_device *pdev)
{
int irq, ret;
@ -2663,9 +2695,20 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
}
smmu->dev = dev;
if (dev->of_node) {
ret = arm_smmu_device_dt_probe(pdev, smmu);
} else {
ret = arm_smmu_device_acpi_probe(pdev, smmu);
if (ret == -ENODEV)
return ret;
}
/* Set bypass mode according to firmware probing result */
bypass = !!ret;
/* Base address */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (resource_size(res) + 1 < SZ_128K) {
if (resource_size(res) + 1 < arm_smmu_resource_size(smmu)) {
dev_err(dev, "MMIO region too small (%pr)\n", res);
return -EINVAL;
}
@ -2692,17 +2735,6 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
if (irq > 0)
smmu->gerr_irq = irq;
if (dev->of_node) {
ret = arm_smmu_device_dt_probe(pdev, smmu);
} else {
ret = arm_smmu_device_acpi_probe(pdev, smmu);
if (ret == -ENODEV)
return ret;
}
/* Set bypass mode according to firmware probing result */
bypass = !!ret;
/* Probe the h/w */
ret = arm_smmu_device_hw_probe(smmu);
if (ret)