Re: [PATCH v7 3/5] iommu/arm-smmu: introduction of ACTLR for custom prefetcher settings

[Bibek Kumar Patro]

On 1/12/2024 6:44 PM, Dmitry Baryshkov wrote:
> On Fri, 12 Jan 2024 at 15:07, Bibek Kumar Patro
> <quic_bibekkum@xxxxxxxxxxx> wrote:
> > On 1/12/2024 3:31 PM, Konrad Dybcio wrote:
> > > On 1/11/24 19:09, Bibek Kumar Patro wrote:
> > > > On 1/10/2024 11:26 PM, Konrad Dybcio wrote:
> > > > > On 1/10/24 13:55, Bibek Kumar Patro wrote:
> > > > > > On 1/10/2024 4:46 PM, Bibek Kumar Patro wrote:
> > > > > > > On 1/10/2024 9:36 AM, Pavan Kondeti wrote:
> > > > > >
> > > > > > [...]
> > > > > >
> > > > > > > > > @@ -274,6 +321,21 @@ static const struct of_device_id
> > > > > > > > > qcom_smmu_client_of_match[] __maybe_unused = {
> > > > > > > > >    static int qcom_smmu_init_context(struct arm_smmu_domain
> > > > > > > > > *smmu_domain,
> > > > > > > > >            struct io_pgtable_cfg *pgtbl_cfg, struct device *dev)
> > > > > > > > >    {
> > > > > > > > > +    struct arm_smmu_device *smmu = smmu_domain->smmu;
> > > > > > > > > +    struct qcom_smmu *qsmmu = to_qcom_smmu(smmu);
> > > > > > > > > +    const struct actlr_variant *actlrvar;
> > > > > > > > > +    int cbndx = smmu_domain->cfg.cbndx;
> > > > > > > > > +
> > > > > > > > > +    if (qsmmu->data->actlrvar) {
> > > > > > > > > +        actlrvar = qsmmu->data->actlrvar;
> > > > > > > > > +        for (; actlrvar->io_start; actlrvar++) {
> > > > > > > > > +            if (actlrvar->io_start == smmu->ioaddr) {
> > > > > > > > > +                qcom_smmu_set_actlr(dev, smmu, cbndx,
> > > > > > > > > actlrvar->actlrcfg);
> > > > > > > > > +                break;
> > > > > > > > > +            }
> > > > > > > > > +        }
> > > > > > > > > +    }
> > > > > > > > > +
> > > > > > > >
> > > > > > > > This block and the one in qcom_adreno_smmu_init_context() are exactly
> > > > > > > > the same. Possible to do some refactoring?
> > > > > > >
> > > > > > > I will check if this repeated blocks can be accomodated this into
> > > > > > > qcom_smmu_set_actlr function if that would be fine.
> > > > > >
> > > > > > Also adding to this, this might increase the number of indentation
> > > > > > inside qcom_smmu_set_actlr as well, to around 5. So wouldn't this
> > > > > > be an issue?
> > > > >
> > > > > By the way, we can refactor this:
> > > > >
> > > > > if (qsmmu->data->actlrvar) {
> > > > >       actlrvar = qsmmu->data->actlrvar;
> > > > >       for (; actlrvar->io_start; actlrvar++) {
> > > > >           if (actlrvar->io_start == smmu->ioaddr) {
> > > > >               qcom_smmu_set_actlr(dev, smmu, cbndx, actlrvar->actlrcfg);
> > > > >               break;
> > > > >           }
> > > > >       }
> > > > > }
> > > > >
> > > > > into
> > > > >
> > > > > // add const u8 num_actlrcfgs to struct actrl_variant to
> > > > > // save on sentinel space:
> > > > > //   sizeof(u8) < sizeof(ptr) + sizeof(resource_size_t)
> > > >
> > > > Git it, Would it be better to add this in struct qcom_smmu_match_data ?
> > >
> > > Yes, right.
> >
> > Actually, I noticed now, we can do both the actlr_config (num_actlrcfg
> > is used) and actlr_var (num_smmu is used) in the similar by storing the
> > number of elements in each of them.
> > something like this:
> >
> > +static const struct actlr_config sc7280_apps_actlr_cfg[] = {
> > +       { 0x0800, 0x24e1, PREFETCH_DEFAULT | CMTLB },
> > +       { 0x2000, 0x0163, PREFETCH_DEFAULT | CMTLB },
> > +       { 0x2080, 0x0461, PREFETCH_DEFAULT | CMTLB },
> > +       { 0x2100, 0x0161, PREFETCH_DEFAULT | CMTLB },
> > +       { 0x0900, 0x0407, PREFETCH_SHALLOW | CPRE | CMTLB },
> > +       { 0x2180, 0x0027, PREFETCH_SHALLOW | CPRE | CMTLB },
> > +       { 0x1000, 0x07ff, PREFETCH_DEEP | CPRE | CMTLB },
> > +};
> > +
> > +static const struct actlr_config sc7280_gfx_actlr_cfg[] = {
> > +       { 0x0000, 0x07ff, PREFETCH_SWITCH_GFX | PREFETCH_DEEP | CPRE | CMTLB },
> > +};
> > +
> > +static const struct actlr_variant sc7280_actlr[] = {
> > +       { .io_start = 0x15000000, .actlrcfg = sc7280_apps_actlr_cfg,
> > .num_actlrcfg = 7 },
> > +       { .io_start = 0x03da0000, .actlrcfg = sc7280_gfx_actlr_cfg,
> > .num_actlrcfg = 1 },
> > +};
> > +
> >    static const struct actlr_config sm8550_apps_actlr_cfg[] = {
> >          { 0x18a0, 0x0000, PREFETCH_SHALLOW | CPRE | CMTLB },
> >          { 0x18e0, 0x0000, PREFETCH_SHALLOW | CPRE | CMTLB },
> > @@ -661,6 +680,13 @@ static const struct qcom_smmu_match_data
> > sdm845_smmu_500_data = {
> >          /* Also no debug configuration. */
> >    };
> >
> > +static const struct qcom_smmu_match_data sc7280_smmu_500_impl0_data = {
> > +       .impl = &qcom_smmu_500_impl,
> > +       .adreno_impl = &qcom_adreno_smmu_500_impl,
> > +       .cfg = &qcom_smmu_impl0_cfg,
> > +       .actlrvar = sc7280_actlr,
> > +       .num_smmu = 2,
> > +};
> >
> > Just for note , there's a small hiccup here as we have to manually
> > calculate and the number of elements in actlr_config size everytime we
> > add this info for a new target, won't be an issue though but just a
> > hindrance to automation (?)
>
> Just use ARRAY_SIZE(sc7280_actlr).

Noted, ARRAY_SIZE makes sense now for this new io_address based
matching.

Thanks & regards,
Bibek

>