Re: [PATCH v9 13/13] coresight-tpdm: Add nodes for dsb msr support

[Tao Zhang <quic_taozha@xxxxxxxxxxx>]

On 9/26/2023 7:46 PM, Suzuki K Poulose wrote:
> On 14/09/2023 06:43, Tao Zhang wrote:
> > Add the nodes for DSB subunit MSR(mux select register) support.
> > The TPDM MSR (mux select register) interface is an optional
> > interface and associated bank of registers per TPDM subunit.
> > The intent of mux select registers is to control muxing structures
> > driving the TPDM’s’ various subunit interfaces.
> >
> > Signed-off-by: Tao Zhang <quic_taozha@xxxxxxxxxxx>
> > ---
> >   .../ABI/testing/sysfs-bus-coresight-devices-tpdm   |  8 +++
> >   drivers/hwtracing/coresight/coresight-tpdm.c       | 81 
> > ++++++++++++++++++++++
> >   drivers/hwtracing/coresight/coresight-tpdm.h       | 12 ++++
> >   3 files changed, 101 insertions(+)
> >
> > diff --git 
> > a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm 
> > b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
> > index 1f20a3f..f07218e 100644
> > --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
> > +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
> > @@ -162,3 +162,11 @@ Description:
> >           Accepts only one of the 2 values -  0 or 1.
> >           0 : Set the DSB pattern type to value.
> >           1 : Set the DSB pattern type to toggle.
> > +
> > +What: /sys/bus/coresight/devices/<tpdm-name>/dsb_msr/msr[0:31]
> > +Date:        March 2023
> > +KernelVersion    6.7
> > +Contact:    Jinlong Mao (QUIC) <quic_jinlmao@xxxxxxxxxxx>, Tao Zhang 
> > (QUIC) <quic_taozha@xxxxxxxxxxx>
> > +Description:
> > +        (RW) Set/Get the MSR(mux select register) for the DSB subunit
> > +        TPDM.
> > diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c 
> > b/drivers/hwtracing/coresight/coresight-tpdm.c
> > index 7acc220..ea29e05 100644
> > --- a/drivers/hwtracing/coresight/coresight-tpdm.c
> > +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
> > @@ -61,6 +61,11 @@ static ssize_t tpdm_simple_dataset_show(struct 
> > device *dev,
> >               return -EINVAL;
> >           return sysfs_emit(buf, "0x%x\n",
> >               drvdata->dsb->patt_mask[tpdm_attr->idx]);
> > +    case DSB_MSR:
> > +        if (tpdm_attr->idx >= drvdata->dsb_msr_num)
> > +            return -EINVAL;
> > +        return sysfs_emit(buf, "0x%x\n",
> > +                drvdata->dsb->msr[tpdm_attr->idx]);
> >       }
> >       return -EINVAL;
> >   }
> > @@ -107,6 +112,12 @@ static ssize_t tpdm_simple_dataset_store(struct 
> > device *dev,
> >           else
> >               ret = -EINVAL;
> >           break;
> > +    case DSB_MSR:
> > +        if (tpdm_attr->idx < drvdata->dsb_msr_num)
> > +            drvdata->dsb->msr[tpdm_attr->idx] = val;
> > +        else
> > +            ret = -EINVAL;
> > +        break;
> >       default:
> >           ret = -EINVAL;
> >       }
> > @@ -132,6 +143,18 @@ static umode_t tpdm_dsb_is_visible(struct 
> > kobject *kobj,
> >       return 0;
> >   }
> >   +static umode_t tpdm_dsb_msr_is_visible(struct kobject *kobj,
> > +                       struct attribute *attr, int n)
> > +{
> > +    struct device *dev = kobj_to_dev(kobj);
> > +    struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
> > +
> > +    if (drvdata->dsb_msr_num != 0)
> > +        return attr->mode;
>
> I did mention in the last review, that we should limit the number of
> files visible based on the number of msrs ?
>     struct tpdm_dataset_attribute *tpdm_attr =
>         container_of(attr, struct tpdm_dataset_attribute, attr);
>
>     if (tpdm_attr->idx < drvdata->dsb_msr_num)
>         return attr->mode;
>
> That way, only the available msrs are listed in the directory ?
>
> Suzuki

Since "device_attribute" is the member of "tpdm_dataset_attribute", not 
"attribute". I need to

get the "device_attribute " pointer first. List the following code I 
have verified. I will post the new

patch series if you agree on this approach.

    struct device_attribute *dev_attr =
        container_of(attr, struct device_attribute, attr);
    struct tpdm_dataset_attribute *tpdm_attr =

        container_of(dev_attr, struct tpdm_dataset_attribute, attr);


    if (tpdm_attr->idx < drvdata->dsb_msr_num)
        return attr->mode;

Best,

Tao

> > +
> > +    return 0;
> > +}
> > +
> >   static void tpdm_reset_datasets(struct tpdm_drvdata *drvdata)
> >   {
> >       if (tpdm_has_dsb_dataset(drvdata)) {
> > @@ -193,6 +216,15 @@ static void set_dsb_tier(struct tpdm_drvdata 
> > *drvdata)
> >       writel_relaxed(val, drvdata->base + TPDM_DSB_TIER);
> >   }
> >   +static void set_dsb_msr(struct tpdm_drvdata *drvdata)
> > +{
> > +    int i;
> > +
> > +    for (i = 0; i < drvdata->dsb_msr_num; i++)
> > +        writel_relaxed(drvdata->dsb->msr[i],
> > +               drvdata->base + TPDM_DSB_MSR(i));
> > +}
> > +
> >   static void tpdm_enable_dsb(struct tpdm_drvdata *drvdata)
> >   {
> >       u32 val, i;
> > @@ -216,6 +248,8 @@ static void tpdm_enable_dsb(struct tpdm_drvdata 
> > *drvdata)
> >         set_dsb_tier(drvdata);
> >   +    set_dsb_msr(drvdata);
> > +
> >       val = readl_relaxed(drvdata->base + TPDM_DSB_CR);
> >       /* Set the mode of DSB dataset */
> >       set_dsb_mode(drvdata, &val);
> > @@ -739,6 +773,42 @@ static struct attribute *tpdm_dsb_patt_attrs[] = {
> >       NULL,
> >   };
> >   +static struct attribute *tpdm_dsb_msr_attrs[] = {
> > +    DSB_MSR_ATTR(0),
> > +    DSB_MSR_ATTR(1),
> > +    DSB_MSR_ATTR(2),
> > +    DSB_MSR_ATTR(3),
> > +    DSB_MSR_ATTR(4),
> > +    DSB_MSR_ATTR(5),
> > +    DSB_MSR_ATTR(6),
> > +    DSB_MSR_ATTR(7),
> > +    DSB_MSR_ATTR(8),
> > +    DSB_MSR_ATTR(9),
> > +    DSB_MSR_ATTR(10),
> > +    DSB_MSR_ATTR(11),
> > +    DSB_MSR_ATTR(12),
> > +    DSB_MSR_ATTR(13),
> > +    DSB_MSR_ATTR(14),
> > +    DSB_MSR_ATTR(15),
> > +    DSB_MSR_ATTR(16),
> > +    DSB_MSR_ATTR(17),
> > +    DSB_MSR_ATTR(18),
> > +    DSB_MSR_ATTR(19),
> > +    DSB_MSR_ATTR(20),
> > +    DSB_MSR_ATTR(21),
> > +    DSB_MSR_ATTR(22),
> > +    DSB_MSR_ATTR(23),
> > +    DSB_MSR_ATTR(24),
> > +    DSB_MSR_ATTR(25),
> > +    DSB_MSR_ATTR(26),
> > +    DSB_MSR_ATTR(27),
> > +    DSB_MSR_ATTR(28),
> > +    DSB_MSR_ATTR(29),
> > +    DSB_MSR_ATTR(30),
> > +    DSB_MSR_ATTR(31),
> > +    NULL,
> > +};
> > +
> >   static struct attribute *tpdm_dsb_attrs[] = {
> >       &dev_attr_dsb_mode.attr,
> >       &dev_attr_dsb_trig_ts.attr,
> > @@ -769,12 +839,19 @@ static struct attribute_group tpdm_dsb_patt_grp 
> > = {
> >       .name = "dsb_patt",
> >   };
> >   +static struct attribute_group tpdm_dsb_msr_grp = {
> > +    .attrs = tpdm_dsb_msr_attrs,
> > +    .is_visible = tpdm_dsb_msr_is_visible,
> > +    .name = "dsb_msr",
> > +};
> > +
> >   static const struct attribute_group *tpdm_attr_grps[] = {
> >       &tpdm_attr_grp,
> >       &tpdm_dsb_attrs_grp,
> >       &tpdm_dsb_edge_grp,
> >       &tpdm_dsb_trig_patt_grp,
> >       &tpdm_dsb_patt_grp,
> > +    &tpdm_dsb_msr_grp,
> >       NULL,
> >   };
> >   @@ -809,6 +886,10 @@ static int tpdm_probe(struct amba_device 
> > *adev, const struct amba_id *id)
> >       if (ret)
> >           return ret;
> >   +    if (drvdata && tpdm_has_dsb_dataset(drvdata))
> > +        of_property_read_u32(drvdata->dev->of_node,
> > +               "qcom,dsb_msr_num", &drvdata->dsb_msr_num);
> > +
> >       /* Set up coresight component description */
> >       desc.name = coresight_alloc_device_name(&tpdm_devs, dev);
> >       if (!desc.name)
> > diff --git a/drivers/hwtracing/coresight/coresight-tpdm.h 
> > b/drivers/hwtracing/coresight/coresight-tpdm.h
> > index 891979d..4115b2a1 100644
> > --- a/drivers/hwtracing/coresight/coresight-tpdm.h
> > +++ b/drivers/hwtracing/coresight/coresight-tpdm.h
> > @@ -18,6 +18,7 @@
> >   #define TPDM_DSB_XPMR(n)    (0x7E8 + (n * 4))
> >   #define TPDM_DSB_EDCR(n)    (0x808 + (n * 4))
> >   #define TPDM_DSB_EDCMR(n)    (0x848 + (n * 4))
> > +#define TPDM_DSB_MSR(n)        (0x980 + (n * 4))
> >     /* Enable bit for DSB subunit */
> >   #define TPDM_DSB_CR_ENA        BIT(0)
> > @@ -90,6 +91,8 @@
> >   #define TPDM_DSB_MAX_EDCMR    8
> >   /* MAX number of DSB pattern */
> >   #define TPDM_DSB_MAX_PATT    8
> > +/* MAX number of DSB MSR */
> > +#define TPDM_DSB_MAX_MSR 32
> >     #define tpdm_simple_dataset_ro(name, mem, idx)            \
> >       (&((struct tpdm_dataset_attribute[]) {            \
> > @@ -134,6 +137,10 @@
> >           tpdm_simple_dataset_rw(tpmr##nr,        \
> >           DSB_PATT_MASK, nr)
> >   +#define DSB_MSR_ATTR(nr)                    \
> > +        tpdm_simple_dataset_rw(msr##nr,            \
> > +        DSB_MSR, nr)
> > +
> >   /**
> >    * struct dsb_dataset - specifics associated to dsb dataset
> >    * @mode:             DSB programming mode
> > @@ -144,6 +151,7 @@
> >    * @patt_mask:        Save value for pattern mask
> >    * @trig_patt:        Save value for trigger pattern
> >    * @trig_patt_mask:   Save value for trigger pattern mask
> > + * @msr               Save value for MSR
> >    * @patt_ts:          Enable/Disable pattern timestamp
> >    * @patt_type:        Set pattern type
> >    * @trig_ts:          Enable/Disable trigger timestamp.
> > @@ -158,6 +166,7 @@ struct dsb_dataset {
> >       u32            patt_mask[TPDM_DSB_MAX_PATT];
> >       u32            trig_patt[TPDM_DSB_MAX_PATT];
> >       u32            trig_patt_mask[TPDM_DSB_MAX_PATT];
> > +    u32            msr[TPDM_DSB_MAX_MSR];
> >       bool            patt_ts;
> >       bool            patt_type;
> >       bool            trig_ts;
> > @@ -173,6 +182,7 @@ struct dsb_dataset {
> >    * @enable:     enable status of the component.
> >    * @datasets:   The datasets types present of the TPDM.
> >    * @dsb         Specifics associated to TPDM DSB.
> > + * @dsb_msr_num Number of MSR supported by DSB TPDM
> >    */
> >     struct tpdm_drvdata {
> > @@ -183,6 +193,7 @@ struct tpdm_drvdata {
> >       bool            enable;
> >       unsigned long        datasets;
> >       struct dsb_dataset    *dsb;
> > +    u32            dsb_msr_num;
> >   };
> >     /* Enumerate members of various datasets */
> > @@ -193,6 +204,7 @@ enum dataset_mem {
> >       DSB_TRIG_PATT_MASK,
> >       DSB_PATT,
> >       DSB_PATT_MASK,
> > +    DSB_MSR,
> >   };
> >     /**