Messages in this thread Patch in this message | | | Date | Thu, 23 Mar 2023 11:51:51 +0000 | Subject | Re: [PATCH v3 02/11] coresight-tpda: Add DSB dataset support | From | Suzuki K Poulose <> |
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On 23/03/2023 06:03, Tao Zhang wrote: > Read the DSB element size from the device tree. Set the register > bit that controls the DSB element size of the corresponding port. > > Signed-off-by: Tao Zhang <quic_taozha@quicinc.com> > --- > drivers/hwtracing/coresight/coresight-tpda.c | 58 ++++++++++++++++++++++++++++ > drivers/hwtracing/coresight/coresight-tpda.h | 4 ++ > 2 files changed, 62 insertions(+) > > diff --git a/drivers/hwtracing/coresight/coresight-tpda.c b/drivers/hwtracing/coresight/coresight-tpda.c > index f712e11..8dcfc4a 100644 > --- a/drivers/hwtracing/coresight/coresight-tpda.c > +++ b/drivers/hwtracing/coresight/coresight-tpda.c > @@ -21,6 +21,47 @@ > > DEFINE_CORESIGHT_DEVLIST(tpda_devs, "tpda"); > > +/* Search and read element data size from the TPDM node in > + * the devicetree. Each input port of TPDA is connected to > + * a TPDM. Different TPDM supports different types of dataset, > + * and some may support more than one type of dataset. > + * Parameter "inport" is used to pass in the input port number > + * of TPDA, and it is set to 0 in the recursize call. > + * Parameter "parent" is used to pass in the original call. > + */
I am still not clear why we need to do this recursively ?
> +static int tpda_set_element_size(struct tpda_drvdata *drvdata, > + struct coresight_device *csdev, int inport, bool parent)
Please could we renamse csdev => tpda_dev
> +{ > + static int nr_inport; > + int i; > + struct coresight_device *in_csdev;
similarly tpdm_dev ?
Could we not add a check here to see if the dsb_esize[inport] is already set and then bail out, reading this over and over ?
> + > + if (inport > (TPDA_MAX_INPORTS - 1)) > + return -EINVAL; > + > + if (parent) > + nr_inport = inport; > + > + for (i = 0; i < csdev->pdata->nr_inconns; i++) { > + in_csdev = csdev->pdata->in_conns[i].remote_dev;
Please note, the names of the structure field might change in the next version of James' series
> + if (!in_csdev) > + break; > + > + if (parent) > + if (csdev->pdata->in_conns[i].port != inport) > + continue; > + > + if (in_csdev && strstr(dev_name(&in_csdev->dev), "tpdm")) {
Isn't there a better way to distinguish a device to be TPDM ? May be we could even add a source_sub_type - SOURCE_TPDM instead of using SOURCE_OTHERS ? Do you expect other sources to be connected to TPDA? e.g., STMs ?
> + of_property_read_u32(in_csdev->dev.parent->of_node, > + "qcom,dsb-element-size", &drvdata->dsb_esize[nr_inport]); > + break; > + } > + tpda_set_element_size(drvdata, in_csdev, 0, false);
What is the point of this ? Is this for covering the a TPDA connected to another TPDA ?
e.g., { TPDM0, TPDM1 } -> TPDA0 -> TPDA1 ?
And you want to figure out the DSB size of TPDM0 when you want to enable TPDA1 ? How do you choose between that size of TPDM0 vs TPDM1 ?
Please add a proper documentation for this function ? If TPDA0 is in the the path, it should have been enabled before you reach TPDA1. Thus, the dsb_esize array must have been initialised for TPDA0 and thus, you could simply read it from the dsb_esize[] of TPDA0. You could always look at the device_type and sub_type to detect a TPDA{0} connected into TPDA{1}
> + } > + > + return 0; > +} > + > /* Settings pre enabling port control register */ > static void tpda_enable_pre_port(struct tpda_drvdata *drvdata) > { > @@ -37,6 +78,18 @@ static void tpda_enable_port(struct tpda_drvdata *drvdata, int port) > u32 val; > > val = readl_relaxed(drvdata->base + TPDA_Pn_CR(port)); > + /* > + * Configure aggregator port n DSB data set element size > + * Set the bit to 0 if the size is 32 > + * Set the bit to 1 if the size is 64 > + */ > + if (drvdata->dsb_esize[port] == 32) > + val &= ~TPDA_Pn_CR_DSBSIZE; > + else if (drvdata->dsb_esize[port] == 64) > + val |= TPDA_Pn_CR_DSBSIZE; > + else > + dev_err(drvdata->dev, > + "DSB data size input from port[%d] is invalid\n", port);
WARN_ON_ONCE() and abort the enable opration ? Or say, "fallback to 32bit or 64bit" if one of them is a safer option ? Please don't leave it unknown.
> /* Enable the port */ > val |= TPDA_Pn_CR_ENA; > writel_relaxed(val, drvdata->base + TPDA_Pn_CR(port)); > @@ -57,6 +110,11 @@ static void __tpda_enable(struct tpda_drvdata *drvdata, int port) > static int tpda_enable(struct coresight_device *csdev, int inport, int outport) > { > struct tpda_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); > + int ret; > + > + ret = tpda_set_element_size(drvdata, csdev, inport, true); > + if (ret) > + return ret; > > spin_lock(&drvdata->spinlock); > if (atomic_read(&csdev->refcnt[inport]) == 0) > diff --git a/drivers/hwtracing/coresight/coresight-tpda.h b/drivers/hwtracing/coresight/coresight-tpda.h > index 0399678..9ec5870 100644 > --- a/drivers/hwtracing/coresight/coresight-tpda.h > +++ b/drivers/hwtracing/coresight/coresight-tpda.h > @@ -10,6 +10,8 @@ > #define TPDA_Pn_CR(n) (0x004 + (n * 4)) > /* Aggregator port enable bit */ > #define TPDA_Pn_CR_ENA BIT(0) > +/* Aggregator port DSB data set element size bit */ > +#define TPDA_Pn_CR_DSBSIZE BIT(8) > > #define TPDA_MAX_INPORTS 32 > > @@ -23,6 +25,7 @@ > * @csdev: component vitals needed by the framework. > * @spinlock: lock for the drvdata value. > * @enable: enable status of the component. > + * @dsb_esize: DSB element size
Please state, must be 32 or 64.
> */ > struct tpda_drvdata { > void __iomem *base; > @@ -30,6 +33,7 @@ struct tpda_drvdata { > struct coresight_device *csdev; > spinlock_t spinlock; > u8 atid; > + u32 dsb_esize[TPDA_MAX_INPORTS];
Couldn't this be u8 ?
Suzuki
> }; > > #endif /* _CORESIGHT_CORESIGHT_TPDA_H */
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