This driver was indexing the contexts by asid-1, which is probably
done under the assumption that the first ASID is always 1.
Unfortunately this is not always true: at least for MSM8956 and
MSM8976's GPU IOMMU, the gpu_user context's ASID number is zero.
To allow using a zero asid number, index the contexts by `asid`
instead of by `asid - 1`.
While at it, also enhance human readability by renaming the
`num_ctxs` member of struct qcom_iommu_dev to `max_asid`.
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
---
drivers/iommu/arm/arm-smmu/qcom_iommu.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu/qcom_iommu.c b/drivers/iommu/arm/arm-smmu/qcom_iommu.c
index f1bd7c035db8..9786fd094e7d 100644
--- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c
+++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c
@@ -51,8 +51,8 @@ struct qcom_iommu_dev {
struct clk_bulk_data clks[CLK_NUM];
void __iomem *local_base;
u32 sec_id;
- u8 num_ctxs;
- struct qcom_iommu_ctx *ctxs[]; /* indexed by asid-1 */
+ u8 max_asid;
+ struct qcom_iommu_ctx *ctxs[]; /* indexed by asid */
};
struct qcom_iommu_ctx {
@@ -94,7 +94,7 @@ static struct qcom_iommu_ctx * to_ctx(struct qcom_iommu_domain *d, unsigned asid
struct qcom_iommu_dev *qcom_iommu = d->iommu;
if (!qcom_iommu)
return NULL;
- return qcom_iommu->ctxs[asid - 1];
+ return qcom_iommu->ctxs[asid];
}
static inline void
@@ -534,12 +534,10 @@ static int qcom_iommu_of_xlate(struct device *dev, struct of_phandle_args *args)
qcom_iommu = platform_get_drvdata(iommu_pdev);
/* make sure the asid specified in dt is valid, so we don't have
- * to sanity check this elsewhere, since 'asid - 1' is used to
- * index into qcom_iommu->ctxs:
+ * to sanity check this elsewhere:
*/
- if (WARN_ON(asid < 1) ||
- WARN_ON(asid > qcom_iommu->num_ctxs) ||
- WARN_ON(qcom_iommu->ctxs[asid - 1] == NULL)) {
+ if (WARN_ON(asid > qcom_iommu->max_asid) ||
+ WARN_ON(qcom_iommu->ctxs[asid] == NULL)) {
put_device(&iommu_pdev->dev);
return -EINVAL;
}
@@ -696,7 +694,7 @@ static int qcom_iommu_ctx_probe(struct platform_device *pdev)
dev_dbg(dev, "found asid %u\n", ctx->asid);
- qcom_iommu->ctxs[ctx->asid - 1] = ctx;
+ qcom_iommu->ctxs[ctx->asid] = ctx;
return 0;
}
@@ -708,7 +706,7 @@ static void qcom_iommu_ctx_remove(struct platform_device *pdev)
platform_set_drvdata(pdev, NULL);
- qcom_iommu->ctxs[ctx->asid - 1] = NULL;
+ qcom_iommu->ctxs[ctx->asid] = NULL;
}
static const struct of_device_id ctx_of_match[] = {
@@ -755,11 +753,11 @@ static int qcom_iommu_device_probe(struct platform_device *pdev)
for_each_child_of_node(dev->of_node, child)
max_asid = max(max_asid, get_asid(child));
- qcom_iommu = devm_kzalloc(dev, struct_size(qcom_iommu, ctxs, max_asid),
+ qcom_iommu = devm_kzalloc(dev, struct_size(qcom_iommu, ctxs, max_asid + 1),
GFP_KERNEL);
if (!qcom_iommu)
return -ENOMEM;
- qcom_iommu->num_ctxs = max_asid;
+ qcom_iommu->max_asid = max_asid;
qcom_iommu->dev = dev;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
--
2.40.1
