* [PATCH] iommu/arm-smmu: Use context bank TLBSTATUS registers
@ 2017-05-22 8:55 vjitta at codeaurora.org
2017-05-22 9:50 ` Robin Murphy
0 siblings, 1 reply; 2+ messages in thread
From: vjitta at codeaurora.org @ 2017-05-22 8:55 UTC (permalink / raw)
To: linux-arm-kernel
From: Vijayanand Jitta <vjitta@codeaurora.org>
There are TLBSTATUS registers in SMMU global register space as well as
context bank register space. Currently we're polling the global
TLBSTATUS registers after TLB invalidation, even when using the TLB
invalidation registers from context bank address space. This violates
the usage model described in the ARM SMMU spec. Fix this by polling
context bank TLBSTATUS registers for context bank TLB operations, and
global TLBSTATUS registers for global TLB operations.
Signed-off-by: Vijayanand Jitta <vjitta@codeaurora.org>
---
drivers/iommu/arm-smmu.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 7cecc37..8dc6da9 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -233,6 +233,9 @@ enum arm_smmu_s2cr_privcfg {
#define ARM_SMMU_CB_S1_TLBIVAL 0x620
#define ARM_SMMU_CB_S2_TLBIIPAS2 0x630
#define ARM_SMMU_CB_S2_TLBIIPAS2L 0x638
+#define ARM_SMMU_CB_TLBSYNC 0x7f0
+#define ARM_SMMU_CB_TLBSTATUS 0x7f4
+#define TLBSTATUS_SACTIVE (1 << 0)
#define ARM_SMMU_CB_ATS1PR 0x800
#define ARM_SMMU_CB_ATSR 0x8f0
@@ -580,6 +583,19 @@ static void __arm_smmu_free_bitmap(unsigned long *map, int idx)
}
/* Wait for any pending TLB invalidations to complete */
+static void arm_smmu_tlb_sync_cb(struct arm_smmu_device *smmu,
+ int cbndx)
+{
+ void __iomem *base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cbndx);
+ u32 val;
+
+ writel_relaxed(0, base + ARM_SMMU_CB_TLBSYNC);
+ if (readl_poll_timeout_atomic(base + ARM_SMMU_CB_TLBSTATUS, val,
+ !(val & TLBSTATUS_SACTIVE),
+ 0, TLB_LOOP_TIMEOUT))
+ dev_err(smmu->dev, "TLBSYNC timeout!\n");
+}
+
static void __arm_smmu_tlb_sync(struct arm_smmu_device *smmu)
{
int count = 0;
@@ -601,7 +617,7 @@ static void __arm_smmu_tlb_sync(struct arm_smmu_device *smmu)
static void arm_smmu_tlb_sync(void *cookie)
{
struct arm_smmu_domain *smmu_domain = cookie;
- __arm_smmu_tlb_sync(smmu_domain->smmu);
+ arm_smmu_tlb_sync_cb(smmu_domain->smmu, smmu_domain->cfg.cbndx);
}
static void arm_smmu_tlb_inv_context(void *cookie)
@@ -616,13 +632,13 @@ static void arm_smmu_tlb_inv_context(void *cookie)
base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
writel_relaxed(ARM_SMMU_CB_ASID(smmu, cfg),
base + ARM_SMMU_CB_S1_TLBIASID);
+ arm_smmu_tlb_sync_cb(smmu, cfg->cbndx);
} else {
base = ARM_SMMU_GR0(smmu);
writel_relaxed(ARM_SMMU_CB_VMID(smmu, cfg),
base + ARM_SMMU_GR0_TLBIVMID);
+ __arm_smmu_tlb_sync(smmu);
}
-
- __arm_smmu_tlb_sync(smmu);
}
static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
--
1.9.1
^ permalink raw reply related [flat|nested] 2+ messages in thread
* [PATCH] iommu/arm-smmu: Use context bank TLBSTATUS registers
2017-05-22 8:55 [PATCH] iommu/arm-smmu: Use context bank TLBSTATUS registers vjitta at codeaurora.org
@ 2017-05-22 9:50 ` Robin Murphy
0 siblings, 0 replies; 2+ messages in thread
From: Robin Murphy @ 2017-05-22 9:50 UTC (permalink / raw)
To: linux-arm-kernel
On 22/05/17 09:55, vjitta at codeaurora.org wrote:
> From: Vijayanand Jitta <vjitta@codeaurora.org>
>
> There are TLBSTATUS registers in SMMU global register space as well as
> context bank register space. Currently we're polling the global
> TLBSTATUS registers after TLB invalidation, even when using the TLB
> invalidation registers from context bank address space. This violates
> the usage model described in the ARM SMMU spec. Fix this by polling
> context bank TLBSTATUS registers for context bank TLB operations, and
> global TLBSTATUS registers for global TLB operations.
Note that these registers don't exist for SMMUv1 stage 2 contexts...
> Signed-off-by: Vijayanand Jitta <vjitta@codeaurora.org>
> ---
> drivers/iommu/arm-smmu.c | 22 +++++++++++++++++++---
> 1 file changed, 19 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
> index 7cecc37..8dc6da9 100644
> --- a/drivers/iommu/arm-smmu.c
> +++ b/drivers/iommu/arm-smmu.c
> @@ -233,6 +233,9 @@ enum arm_smmu_s2cr_privcfg {
> #define ARM_SMMU_CB_S1_TLBIVAL 0x620
> #define ARM_SMMU_CB_S2_TLBIIPAS2 0x630
> #define ARM_SMMU_CB_S2_TLBIIPAS2L 0x638
> +#define ARM_SMMU_CB_TLBSYNC 0x7f0
> +#define ARM_SMMU_CB_TLBSTATUS 0x7f4
> +#define TLBSTATUS_SACTIVE (1 << 0)
> #define ARM_SMMU_CB_ATS1PR 0x800
> #define ARM_SMMU_CB_ATSR 0x8f0
>
> @@ -580,6 +583,19 @@ static void __arm_smmu_free_bitmap(unsigned long *map, int idx)
> }
>
> /* Wait for any pending TLB invalidations to complete */
> +static void arm_smmu_tlb_sync_cb(struct arm_smmu_device *smmu,
> + int cbndx)
> +{
> + void __iomem *base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cbndx);
> + u32 val;
> +
> + writel_relaxed(0, base + ARM_SMMU_CB_TLBSYNC);
> + if (readl_poll_timeout_atomic(base + ARM_SMMU_CB_TLBSTATUS, val,
> + !(val & TLBSTATUS_SACTIVE),
> + 0, TLB_LOOP_TIMEOUT))
> + dev_err(smmu->dev, "TLBSYNC timeout!\n");
> +}
> +
> static void __arm_smmu_tlb_sync(struct arm_smmu_device *smmu)
> {
> int count = 0;
> @@ -601,7 +617,7 @@ static void __arm_smmu_tlb_sync(struct arm_smmu_device *smmu)
> static void arm_smmu_tlb_sync(void *cookie)
> {
> struct arm_smmu_domain *smmu_domain = cookie;
> - __arm_smmu_tlb_sync(smmu_domain->smmu);
> + arm_smmu_tlb_sync_cb(smmu_domain->smmu, smmu_domain->cfg.cbndx);
...which makes this goes wrong for sync-on-unmap with MMU-400/401 (and
any other implementations which may exist) - in practice they will
probably RAZ, leading us to believe it's always inactive.
Anyway, this patch isn't going to apply against 4.12-rc - guess how I
know ;)
Robin.
> }
>
> static void arm_smmu_tlb_inv_context(void *cookie)
> @@ -616,13 +632,13 @@ static void arm_smmu_tlb_inv_context(void *cookie)
> base = ARM_SMMU_CB_BASE(smmu) + ARM_SMMU_CB(smmu, cfg->cbndx);
> writel_relaxed(ARM_SMMU_CB_ASID(smmu, cfg),
> base + ARM_SMMU_CB_S1_TLBIASID);
> + arm_smmu_tlb_sync_cb(smmu, cfg->cbndx);
> } else {
> base = ARM_SMMU_GR0(smmu);
> writel_relaxed(ARM_SMMU_CB_VMID(smmu, cfg),
> base + ARM_SMMU_GR0_TLBIVMID);
> + __arm_smmu_tlb_sync(smmu);
> }
> -
> - __arm_smmu_tlb_sync(smmu);
> }
>
> static void arm_smmu_tlb_inv_range_nosync(unsigned long iova, size_t size,
>
^ permalink raw reply [flat|nested] 2+ messages in thread
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2017-05-22 9:50 ` Robin Murphy
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