2023-08-02 18:26:31

by Easwar Hariharan

[permalink] [raw]
Subject: [PATCH v2 6.4 0/4] ARM SMMUv3 errata for 6.4

Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Robin Murphy <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]

Changelog:
==========
v1 -> v2:
- Backport other relevant errata patches from the same series as MMU-700 erratum 2812531
- v1 link: https://lore.kernel.org/stable/[email protected]/T/#u

Robin Murphy (4):
iommu/arm-smmu-v3: Work around MMU-600 erratum 1076982
iommu/arm-smmu-v3: Document MMU-700 erratum 2812531
iommu/arm-smmu-v3: Add explicit feature for nesting
iommu/arm-smmu-v3: Document nesting-related errata

Documentation/arm64/silicon-errata.rst | 4 ++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 50 +++++++++++++++++++++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 8 ++++
3 files changed, 62 insertions(+)

--
2.25.1



2023-08-02 18:50:49

by Easwar Hariharan

[permalink] [raw]
Subject: [PATCH v2 6.4 1/4] iommu/arm-smmu-v3: Work around MMU-600 erratum 1076982

From: Robin Murphy <[email protected]>

commit f322e8af35c7f23a8c08b595c38d6c855b2d836f upstream

MMU-600 versions prior to r1p0 fail to correctly generate a WFE wakeup
event when the command queue transitions fom full to non-full. We can
easily work around this by simply hiding the SEV capability such that we
fall back to polling for space in the queue - since MMU-600 implements
MSIs we wouldn't expect to need SEV for sync completion either, so this
should have little to no impact.

Signed-off-by: Robin Murphy <[email protected]>
Reviewed-by: Nicolin Chen <[email protected]>
Tested-by: Nicolin Chen <[email protected]>
Link: https://lore.kernel.org/r/08adbe3d01024d8382a478325f73b56851f76e49.1683731256.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Easwar Hariharan <[email protected]>
---
Documentation/arm64/silicon-errata.rst | 2 ++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 29 +++++++++++++++++++++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 6 +++++
3 files changed, 37 insertions(+)

diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index cd46e2b20a81..fd0d60827b08 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -143,6 +143,8 @@ stable kernels.
+----------------+-----------------+-----------------+-----------------------------+
| ARM | MMU-500 | #841119,826419 | N/A |
+----------------+-----------------+-----------------+-----------------------------+
+| ARM | MMU-600 | #1076982 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
+----------------+-----------------+-----------------+-----------------------------+
| Broadcom | Brahma-B53 | N/A | ARM64_ERRATUM_845719 |
+----------------+-----------------+-----------------+-----------------------------+
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 3fd83fb75722..667e7a90706e 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -3429,6 +3429,33 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)
return 0;
}

+#define IIDR_IMPLEMENTER_ARM 0x43b
+#define IIDR_PRODUCTID_ARM_MMU_600 0x483
+
+static void arm_smmu_device_iidr_probe(struct arm_smmu_device *smmu)
+{
+ u32 reg;
+ unsigned int implementer, productid, variant, revision;
+
+ reg = readl_relaxed(smmu->base + ARM_SMMU_IIDR);
+ implementer = FIELD_GET(IIDR_IMPLEMENTER, reg);
+ productid = FIELD_GET(IIDR_PRODUCTID, reg);
+ variant = FIELD_GET(IIDR_VARIANT, reg);
+ revision = FIELD_GET(IIDR_REVISION, reg);
+
+ switch (implementer) {
+ case IIDR_IMPLEMENTER_ARM:
+ switch (productid) {
+ case IIDR_PRODUCTID_ARM_MMU_600:
+ /* Arm erratum 1076982 */
+ if (variant == 0 && revision <= 2)
+ smmu->features &= ~ARM_SMMU_FEAT_SEV;
+ break;
+ }
+ break;
+ }
+}
+
static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)
{
u32 reg;
@@ -3635,6 +3662,8 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu)

smmu->ias = max(smmu->ias, smmu->oas);

+ arm_smmu_device_iidr_probe(smmu);
+
if (arm_smmu_sva_supported(smmu))
smmu->features |= ARM_SMMU_FEAT_SVA;

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index b574c58a3487..5ce47f2e3402 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -69,6 +69,12 @@
#define IDR5_VAX GENMASK(11, 10)
#define IDR5_VAX_52_BIT 1

+#define ARM_SMMU_IIDR 0x18
+#define IIDR_PRODUCTID GENMASK(31, 20)
+#define IIDR_VARIANT GENMASK(19, 16)
+#define IIDR_REVISION GENMASK(15, 12)
+#define IIDR_IMPLEMENTER GENMASK(11, 0)
+
#define ARM_SMMU_CR0 0x20
#define CR0_ATSCHK (1 << 4)
#define CR0_CMDQEN (1 << 3)
--
2.25.1


2023-08-02 19:55:59

by Easwar Hariharan

[permalink] [raw]
Subject: [PATCH v2 6.4 2/4] iommu/arm-smmu-v3: Document MMU-700 erratum 2812531

From: Robin Murphy <[email protected]>

commit 309a15cb16bb075da1c99d46fb457db6a1a2669e upstream

To work around MMU-700 erratum 2812531 we need to ensure that certain
sequences of commands cannot be issued without an intervening sync. In
practice this falls out of our current command-batching machinery
anyway - each batch only contains a single type of invalidation command,
and ends with a sync. The only exception is when a batch is sufficiently
large to need issuing across multiple command queue slots, wherein the
earlier slots will not contain a sync and thus may in theory interleave
with another batch being issued in parallel to create an affected
sequence across the slot boundary.

Since MMU-700 supports range invalidate commands and thus we will prefer
to use them (which also happens to avoid conditions for other errata),
I'm not entirely sure it's even possible for a single high-level
invalidate call to generate a batch of more than 63 commands, but for
the sake of robustness and documentation, wire up an option to enforce
that a sync is always inserted for every slot issued.

The other aspect is that the relative order of DVM commands cannot be
controlled, so DVM cannot be used. Again that is already the status quo,
but since we have at least defined ARM_SMMU_FEAT_BTM, we can explicitly
disable it for documentation purposes even if it's not wired up anywhere
yet.

Signed-off-by: Robin Murphy <[email protected]>
Reviewed-by: Nicolin Chen <[email protected]>
Link: https://lore.kernel.org/r/330221cdfd0003cd51b6c04e7ff3566741ad8374.1683731256.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Easwar Hariharan <[email protected]>
---
Documentation/arm64/silicon-errata.rst | 2 ++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 12 ++++++++++++
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 1 +
3 files changed, 15 insertions(+)

diff --git a/Documentation/arm64/silicon-errata.rst b/Documentation/arm64/silicon-errata.rst
index fd0d60827b08..b0346968765d 100644
--- a/Documentation/arm64/silicon-errata.rst
+++ b/Documentation/arm64/silicon-errata.rst
@@ -145,6 +145,8 @@ stable kernels.
+----------------+-----------------+-----------------+-----------------------------+
| ARM | MMU-600 | #1076982 | N/A |
+----------------+-----------------+-----------------+-----------------------------+
+| ARM | MMU-700 | #2812531 | N/A |
++----------------+-----------------+-----------------+-----------------------------+
+----------------+-----------------+-----------------+-----------------------------+
| Broadcom | Brahma-B53 | N/A | ARM64_ERRATUM_845719 |
+----------------+-----------------+-----------------+-----------------------------+
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 667e7a90706e..b0ccd735f8bb 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -894,6 +894,12 @@ static void arm_smmu_cmdq_batch_add(struct arm_smmu_device *smmu,
{
int index;

+ if (cmds->num == CMDQ_BATCH_ENTRIES - 1 &&
+ (smmu->options & ARM_SMMU_OPT_CMDQ_FORCE_SYNC)) {
+ arm_smmu_cmdq_issue_cmdlist(smmu, cmds->cmds, cmds->num, true);
+ cmds->num = 0;
+ }
+
if (cmds->num == CMDQ_BATCH_ENTRIES) {
arm_smmu_cmdq_issue_cmdlist(smmu, cmds->cmds, cmds->num, false);
cmds->num = 0;
@@ -3431,6 +3437,7 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu, bool bypass)

#define IIDR_IMPLEMENTER_ARM 0x43b
#define IIDR_PRODUCTID_ARM_MMU_600 0x483
+#define IIDR_PRODUCTID_ARM_MMU_700 0x487

static void arm_smmu_device_iidr_probe(struct arm_smmu_device *smmu)
{
@@ -3451,6 +3458,11 @@ static void arm_smmu_device_iidr_probe(struct arm_smmu_device *smmu)
if (variant == 0 && revision <= 2)
smmu->features &= ~ARM_SMMU_FEAT_SEV;
break;
+ case IIDR_PRODUCTID_ARM_MMU_700:
+ /* Arm erratum 2812531 */
+ smmu->features &= ~ARM_SMMU_FEAT_BTM;
+ smmu->options |= ARM_SMMU_OPT_CMDQ_FORCE_SYNC;
+ break;
}
break;
}
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 5ce47f2e3402..1555c8220381 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -650,6 +650,7 @@ struct arm_smmu_device {
#define ARM_SMMU_OPT_SKIP_PREFETCH (1 << 0)
#define ARM_SMMU_OPT_PAGE0_REGS_ONLY (1 << 1)
#define ARM_SMMU_OPT_MSIPOLL (1 << 2)
+#define ARM_SMMU_OPT_CMDQ_FORCE_SYNC (1 << 3)
u32 options;

struct arm_smmu_cmdq cmdq;
--
2.25.1


2023-08-04 12:23:45

by Greg Kroah-Hartman

[permalink] [raw]
Subject: Re: [PATCH v2 6.4 0/4] ARM SMMUv3 errata for 6.4

On Wed, Aug 02, 2023 at 05:26:16PM +0000, Easwar Hariharan wrote:
> Cc: Catalin Marinas <[email protected]>
> Cc: Will Deacon <[email protected]>
> Cc: Jonathan Corbet <[email protected]>
> Cc: Robin Murphy <[email protected]>
> Cc: Joerg Roedel <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
>
> Changelog:
> ==========
> v1 -> v2:
> - Backport other relevant errata patches from the same series as MMU-700 erratum 2812531
> - v1 link: https://lore.kernel.org/stable/[email protected]/T/#u
>
> Robin Murphy (4):
> iommu/arm-smmu-v3: Work around MMU-600 erratum 1076982
> iommu/arm-smmu-v3: Document MMU-700 erratum 2812531
> iommu/arm-smmu-v3: Add explicit feature for nesting
> iommu/arm-smmu-v3: Document nesting-related errata
>
> Documentation/arm64/silicon-errata.rst | 4 ++
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 50 +++++++++++++++++++++
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 8 ++++
> 3 files changed, 62 insertions(+)
>
> --
> 2.25.1
>

All now queued up, thanks.

greg k-h