| Message ID | 20230622092742.74819-5-angelogioacchino.delregno@collabora.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
| Series | Add support for Qualcomm's legacy IOMMU v2 | expand |
On 22.06.2023 11:27, AngeloGioacchino Del Regno wrote: > 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@collabora.com> > --- Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org> Konrad > 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);
On Thu, Jun 22, 2023 at 11:27:40AM +0200, AngeloGioacchino Del Regno wrote: > 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@collabora.com> > --- > 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); So is this '+ 1' there to handle the case where ASIDs are indexed from 1? If so, please add a comment because this isn't obvious at all. Will
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);
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@collabora.com> --- drivers/iommu/arm/arm-smmu/qcom_iommu.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-)