[PATCH v3 4/8] iommu/arm-smmu-v3: move stall_enabled to the cd table

From: Michael Shavit
Date: Tue Aug 01 2023 - 14:39:26 EST


This controls whether CD entries will have the stall bit set when
writing entries into the table.

Signed-off-by: Michael Shavit <mshavit@xxxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
---

(no changes since v2)

Changes in v2:
- Use a bitfield instead of a bool for stall_enabled

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 8 ++++----
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 3 ++-
2 files changed, 6 insertions(+), 5 deletions(-)

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 fe4b19c3b8dee..c01023404c26c 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -1114,7 +1114,7 @@ int arm_smmu_write_ctx_desc(struct arm_smmu_domain *smmu_domain, int ssid,
FIELD_PREP(CTXDESC_CD_0_ASID, cd->asid) |
CTXDESC_CD_0_V;

- if (smmu_domain->stall_enabled)
+ if (smmu_domain->cd_table.stall_enabled)
val |= CTXDESC_CD_0_S;
}

@@ -1141,6 +1141,7 @@ static int arm_smmu_alloc_cd_tables(struct arm_smmu_domain *smmu_domain,
struct arm_smmu_device *smmu = smmu_domain->smmu;
struct arm_smmu_ctx_desc_cfg *cdcfg = &smmu_domain->cd_table;

+ cdcfg->stall_enabled = master->stall_enabled;
cdcfg->max_cds_bits = master->ssid_bits;
max_contexts = 1 << cdcfg->max_cds_bits;

@@ -2121,8 +2122,6 @@ static int arm_smmu_domain_finalise_s1(struct arm_smmu_domain *smmu_domain,
if (ret)
goto out_unlock;

- smmu_domain->stall_enabled = master->stall_enabled;
-
ret = arm_smmu_alloc_cd_tables(smmu_domain, master);
if (ret)
goto out_free_asid;
@@ -2461,7 +2460,8 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
ret = -EINVAL;
goto out_unlock;
} else if (smmu_domain->stage == ARM_SMMU_DOMAIN_S1 &&
- smmu_domain->stall_enabled != master->stall_enabled) {
+ smmu_domain->cd_table.stall_enabled !=
+ master->stall_enabled) {
ret = -EINVAL;
goto out_unlock;
}
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 35a93e8858872..05b1f0ee60808 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -597,6 +597,8 @@ struct arm_smmu_ctx_desc_cfg {
unsigned int num_l1_ents;
/* log2 of the maximum number of CDs supported by this table */
u8 max_cds_bits;
+ /* Whether CD entries in this table have the stall bit set. */
+ u8 stall_enabled:1;
};

struct arm_smmu_s2_cfg {
@@ -714,7 +716,6 @@ struct arm_smmu_domain {
struct mutex init_mutex; /* Protects smmu pointer */

struct io_pgtable_ops *pgtbl_ops;
- bool stall_enabled;
atomic_t nr_ats_masters;

enum arm_smmu_domain_stage stage;
--
2.41.0.585.gd2178a4bd4-goog