Re: [PATCH] iommu/qcom: Use domain rather than dev as tlb cookie

[Naresh Kamboju]

On Mon, 20 Jul 2020 at 21:21, Rob Clark <robdclark@xxxxxxxxx> wrote:
>
> From: Rob Clark <robdclark@xxxxxxxxxxxx>
>
> The device may be torn down, but the domain should still be valid.  Lets
> use that as the tlb flush ops cookie.
>
> Fixes a problem reported in [1]

This proposed fix patch applied on top of linux mainline master
and boot test PASS on db410c.

The reported problem got fixed.

>
> [1] https://lkml.org/lkml/2020/7/20/104
>
> Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>

Reported-by: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>
Tested-by: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>

> ---
> Note I don't have a good setup to test this atm, but I think it should
> work.
>
>  drivers/iommu/qcom_iommu.c | 37 +++++++++++++++++--------------------
>  1 file changed, 17 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c
> index c3e1fbd1988c..d176df569af8 100644
> --- a/drivers/iommu/qcom_iommu.c
> +++ b/drivers/iommu/qcom_iommu.c
> @@ -65,6 +65,7 @@ struct qcom_iommu_domain {
>         struct mutex             init_mutex; /* Protects iommu pointer */
>         struct iommu_domain      domain;
>         struct qcom_iommu_dev   *iommu;
> +       struct iommu_fwspec     *fwspec;
>  };
>
>  static struct qcom_iommu_domain *to_qcom_iommu_domain(struct iommu_domain *dom)
> @@ -84,9 +85,9 @@ static struct qcom_iommu_dev * to_iommu(struct device *dev)
>         return dev_iommu_priv_get(dev);
>  }
>
> -static struct qcom_iommu_ctx * to_ctx(struct device *dev, unsigned asid)
> +static struct qcom_iommu_ctx * to_ctx(struct qcom_iommu_domain *d, unsigned asid)
>  {
> -       struct qcom_iommu_dev *qcom_iommu = to_iommu(dev);
> +       struct qcom_iommu_dev *qcom_iommu = d->iommu;
>         if (!qcom_iommu)
>                 return NULL;
>         return qcom_iommu->ctxs[asid - 1];
> @@ -118,14 +119,12 @@ iommu_readq(struct qcom_iommu_ctx *ctx, unsigned reg)
>
>  static void qcom_iommu_tlb_sync(void *cookie)
>  {
> -       struct iommu_fwspec *fwspec;
> -       struct device *dev = cookie;
> +       struct qcom_iommu_domain *qcom_domain = cookie;
> +       struct iommu_fwspec *fwspec = qcom_domain->fwspec;
>         unsigned i;
>
> -       fwspec = dev_iommu_fwspec_get(dev);
> -
>         for (i = 0; i < fwspec->num_ids; i++) {
> -               struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
> +               struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
>                 unsigned int val, ret;
>
>                 iommu_writel(ctx, ARM_SMMU_CB_TLBSYNC, 0);
> @@ -139,14 +138,12 @@ static void qcom_iommu_tlb_sync(void *cookie)
>
>  static void qcom_iommu_tlb_inv_context(void *cookie)
>  {
> -       struct device *dev = cookie;
> -       struct iommu_fwspec *fwspec;
> +       struct qcom_iommu_domain *qcom_domain = cookie;
> +       struct iommu_fwspec *fwspec = qcom_domain->fwspec;
>         unsigned i;
>
> -       fwspec = dev_iommu_fwspec_get(dev);
> -
>         for (i = 0; i < fwspec->num_ids; i++) {
> -               struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
> +               struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
>                 iommu_writel(ctx, ARM_SMMU_CB_S1_TLBIASID, ctx->asid);
>         }
>
> @@ -156,16 +153,14 @@ static void qcom_iommu_tlb_inv_context(void *cookie)
>  static void qcom_iommu_tlb_inv_range_nosync(unsigned long iova, size_t size,
>                                             size_t granule, bool leaf, void *cookie)
>  {
> -       struct device *dev = cookie;
> -       struct iommu_fwspec *fwspec;
> +       struct qcom_iommu_domain *qcom_domain = cookie;
> +       struct iommu_fwspec *fwspec = qcom_domain->fwspec;
>         unsigned i, reg;
>
>         reg = leaf ? ARM_SMMU_CB_S1_TLBIVAL : ARM_SMMU_CB_S1_TLBIVA;
>
> -       fwspec = dev_iommu_fwspec_get(dev);
> -
>         for (i = 0; i < fwspec->num_ids; i++) {
> -               struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
> +               struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
>                 size_t s = size;
>
>                 iova = (iova >> 12) << 12;
> @@ -256,7 +251,9 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain,
>         };
>
>         qcom_domain->iommu = qcom_iommu;
> -       pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, dev);
> +       qcom_domain->fwspec = fwspec;
> +
> +       pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, qcom_domain);
>         if (!pgtbl_ops) {
>                 dev_err(qcom_iommu->dev, "failed to allocate pagetable ops\n");
>                 ret = -ENOMEM;
> @@ -269,7 +266,7 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain,
>         domain->geometry.force_aperture = true;
>
>         for (i = 0; i < fwspec->num_ids; i++) {
> -               struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
> +               struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
>
>                 if (!ctx->secure_init) {
>                         ret = qcom_scm_restore_sec_cfg(qcom_iommu->sec_id, ctx->asid);
> @@ -419,7 +416,7 @@ static void qcom_iommu_detach_dev(struct iommu_domain *domain, struct device *de
>
>         pm_runtime_get_sync(qcom_iommu->dev);
>         for (i = 0; i < fwspec->num_ids; i++) {
> -               struct qcom_iommu_ctx *ctx = to_ctx(dev, fwspec->ids[i]);
> +               struct qcom_iommu_ctx *ctx = to_ctx(qcom_domain, fwspec->ids[i]);
>
>                 /* Disable the context bank: */
>                 iommu_writel(ctx, ARM_SMMU_CB_SCTLR, 0);

-- 
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https://lkft.linaro.org