[PATCH v6 5/6] iommu/tegra-smmu: Attach as pointer to tegra_smmu_group

Nicolin Chen
2021-09-14T01:47:42Z

This could ease driver to access corresponding as pointer
when having tegra_smmu_group pointer only, which can help
new mappings debugfs nodes.

Also moving tegra_smmu_find_group_soc() upward, for using
it in new tegra_smmu_attach_as(); and it's better to have
all tegra_smmu_find_* functions together.

Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
---
drivers/iommu/tegra-smmu.c | 94 +++++++++++++++++++++++++++++++-------
1 file changed, 78 insertions(+), 16 deletions(-)

diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c
index 8fd4985ac91e..68c34a4a0ecc 100644
--- a/drivers/iommu/tegra-smmu.c
+++ b/drivers/iommu/tegra-smmu.c
@@ -24,6 +24,7 @@ struct tegra_smmu_group {
struct tegra_smmu *smmu;
const struct tegra_smmu_group_soc *group_soc;
const struct tegra_smmu_swgroup *swgrp;
+ struct tegra_smmu_as *as;
struct iommu_group *grp;
};

@@ -349,6 +350,19 @@ tegra_smmu_find_swgrp(struct tegra_smmu *smmu, unsigned int swgroup)
return swgrp;
}

+static const struct tegra_smmu_group_soc *
+tegra_smmu_find_group_soc(struct tegra_smmu *smmu, unsigned int swgroup)
+{
+ unsigned int i, j;
+
+ for (i = 0; i < smmu->soc->num_groups; i++)
+ for (j = 0; j < smmu->soc->groups[i].num_swgroups; j++)
+ if (smmu->soc->groups[i].swgroups[j] == swgroup)
+ return &smmu->soc->groups[i];
+
+ return NULL;
+}
+
static void tegra_smmu_enable(struct tegra_smmu *smmu, unsigned int swgroup,
unsigned int asid)
{
@@ -482,6 +496,57 @@ static void tegra_smmu_as_unprepare(struct tegra_smmu *smmu,
mutex_unlock(&smmu->lock);
}

+static void tegra_smmu_attach_as(struct tegra_smmu *smmu,
+ struct tegra_smmu_as *as,
+ unsigned int swgroup)
+{
+ const struct tegra_smmu_swgroup *swgrp;
+ struct tegra_smmu_group *group;
+
+ /* Find swgrp according to the swgroup id */
+ swgrp = tegra_smmu_find_swgrp(smmu, swgroup);
+ if (!swgrp)
+ return;
+
+ mutex_lock(&smmu->lock);
+
+ list_for_each_entry(group, &smmu->groups, list) {
+ if (group->swgrp != swgrp)
+ continue;
+ if (group->as)
+ dev_warn(smmu->dev,
+ "overwriting group->as for swgroup: %s\n", swgrp->name);
+ group->as = as;
+ break;
+ }
+
+ mutex_unlock(&smmu->lock);
+}
+
+static void tegra_smmu_detach_as(struct tegra_smmu *smmu,
+ unsigned int swgroup)
+{
+ const struct tegra_smmu_swgroup *swgrp;
+ struct tegra_smmu_group *group;
+ struct dentry *d;
+
+ /* Find swgrp according to the swgroup id */
+ swgrp = tegra_smmu_find_swgrp(smmu, swgroup);
+ if (!swgrp)
+ return;
+
+ mutex_lock(&smmu->lock);
+
+ list_for_each_entry(group, &smmu->groups, list) {
+ if (group->swgrp != swgrp)
+ continue;
+ group->as = NULL;
+ break;
+ }
+
+ mutex_unlock(&smmu->lock);
+}
+
static int tegra_smmu_attach_dev(struct iommu_domain *domain,
struct device *dev)
{
@@ -495,11 +560,15 @@ static int tegra_smmu_attach_dev(struct iommu_domain *domain,
return -ENOENT;

for (index = 0; index < fwspec->num_ids; index++) {
+ unsigned int swgroup = fwspec->ids[index];
+
err = tegra_smmu_as_prepare(smmu, as);
if (err)
goto disable;

- tegra_smmu_enable(smmu, fwspec->ids[index], as->id);
+ tegra_smmu_attach_as(smmu, as, swgroup);
+
+ tegra_smmu_enable(smmu, swgroup, as->id);
}

if (index == 0)
@@ -509,7 +578,10 @@ static int tegra_smmu_attach_dev(struct iommu_domain *domain,

disable:
while (index--) {
- tegra_smmu_disable(smmu, fwspec->ids[index], as->id);
+ unsigned int swgroup = fwspec->ids[index];
+
+ tegra_smmu_disable(smmu, swgroup, as->id);
+ tegra_smmu_detach_as(smmu, swgroup);
tegra_smmu_as_unprepare(smmu, as);
}

@@ -527,7 +599,10 @@ static void tegra_smmu_detach_dev(struct iommu_domain *domain, struct device *de
return;

for (index = 0; index < fwspec->num_ids; index++) {
- tegra_smmu_disable(smmu, fwspec->ids[index], as->id);
+ unsigned int swgroup = fwspec->ids[index];
+
+ tegra_smmu_disable(smmu, swgroup, as->id);
+ tegra_smmu_detach_as(smmu, swgroup);
tegra_smmu_as_unprepare(smmu, as);
}
}
@@ -869,19 +944,6 @@ static struct iommu_device *tegra_smmu_probe_device(struct device *dev)

static void tegra_smmu_release_device(struct device *dev) {}

-static const struct tegra_smmu_group_soc *
-tegra_smmu_find_group_soc(struct tegra_smmu *smmu, unsigned int swgroup)
-{
- unsigned int i, j;
-
- for (i = 0; i < smmu->soc->num_groups; i++)
- for (j = 0; j < smmu->soc->groups[i].num_swgroups; j++)
- if (smmu->soc->groups[i].swgroups[j] == swgroup)
- return &smmu->soc->groups[i];
-
- return NULL;
-}
-
static void tegra_smmu_group_release(void *iommu_data)
{
struct tegra_smmu_group *group = iommu_data;
--
2.17.1