[PATCH v3 2/8] coresight-tpda: Add support to configure CMB element
Suzuki K Poulose
suzuki.poulose at arm.com
Tue Dec 19 05:54:00 PST 2023
On 19/12/2023 02:13, Tao Zhang wrote:
>
> On 12/18/2023 6:27 PM, Suzuki K Poulose wrote:
>> On 21/11/2023 02:24, Tao Zhang wrote:
>>> Read the CMB element size from the device tree. Set the register
>>> bit that controls the CMB element size of the corresponding port.
>>>
>>> Signed-off-by: Tao Zhang <quic_taozha at quicinc.com>
>>> Signed-off-by: Mao Jinlong <quic_jinlmao at quicinc.com>
>>> ---
>>> drivers/hwtracing/coresight/coresight-tpda.c | 117 +++++++++++--------
>>> drivers/hwtracing/coresight/coresight-tpda.h | 6 +
>>> 2 files changed, 74 insertions(+), 49 deletions(-)
>>>
>>> diff --git a/drivers/hwtracing/coresight/coresight-tpda.c
>>> b/drivers/hwtracing/coresight/coresight-tpda.c
>>> index 5f82737c37bb..e3762f38abb3 100644
>>> --- a/drivers/hwtracing/coresight/coresight-tpda.c
>>> +++ b/drivers/hwtracing/coresight/coresight-tpda.c
>>> @@ -28,24 +28,54 @@ static bool coresight_device_is_tpdm(struct
>>> coresight_device *csdev)
>>> CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM);
>>> }
>>> +static void tpdm_clear_element_size(struct coresight_device *csdev)
>>> +{
>>> + struct tpda_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
>>> +
>>> + if (drvdata->dsb_esize)
>>> + drvdata->dsb_esize = 0;
>>> + if (drvdata->cmb_esize)
>>> + drvdata->cmb_esize = 0;
>>
>> Why do we need the if (...) check here ?
>
> The element size of all the TPDM sub-unit should be set to 0 here.
>
> I will update this in the next patch series.
>
>>
>>> +}
>>> +
>>> +static void tpda_set_element_size(struct tpda_drvdata *drvdata, u32
>>> *val)
>>> +{
>>> +
>>> + if (drvdata->dsb_esize == 64)
>>> + *val |= TPDA_Pn_CR_DSBSIZE;
>>> + else if (drvdata->dsb_esize == 32)
>>> + *val &= ~TPDA_Pn_CR_DSBSIZE;
>>> +
>>> + if (drvdata->cmb_esize == 64)
>>> + *val |= FIELD_PREP(TPDA_Pn_CR_CMBSIZE, 0x2);
>>> + else if (drvdata->cmb_esize == 32)
>>> + *val |= FIELD_PREP(TPDA_Pn_CR_CMBSIZE, 0x1);
>>> + else if (drvdata->cmb_esize == 8)
>>> + *val &= ~TPDA_Pn_CR_CMBSIZE;
>>> +}
>>> +
>>
>>
>>> /*
>>> - * Read the DSB element size from the TPDM device
>>> + * Read the element size from the TPDM device
>>> * Returns
>>> - * The dsb element size read from the devicetree if available.
>>> + * The element size read from the devicetree if available.
>>> * 0 - Otherwise, with a warning once.
>>
>> This doesn't match the function ? It return 0 on success and
>> error (-EINVAL) on failure ?
>
> 0 means the element size property is found from the devicetree.
>
> Otherwise, it will return error(-EINVAL).
>
> I will update this in the next patch series.
>
>>
>>> */
>>> -static int tpdm_read_dsb_element_size(struct coresight_device *csdev)
>>> +static int tpdm_read_element_size(struct tpda_drvdata *drvdata,
>>> + struct coresight_device *csdev)
>>> {
>>> - int rc = 0;
>>> - u8 size = 0;
>>> -
>>> - rc = fwnode_property_read_u8(dev_fwnode(csdev->dev.parent),
>>> - "qcom,dsb-element-size", &size);
>>> + int rc = -EINVAL;
>>> +
>>> + if (!fwnode_property_read_u8(dev_fwnode(csdev->dev.parent),
>>> + "qcom,dsb-element-size", &drvdata->dsb_esize))
>>> + rc = 0;
>>> + if (!fwnode_property_read_u8(dev_fwnode(csdev->dev.parent),
>>> + "qcom,cmb-element-size", &drvdata->cmb_esize))
>>> + rc = 0;
>>
>> Are we not silently resetting the error if the former failed ?
>>
>> Could we not :
>>
>> rc |= fwnode_...
>>
>> rc |= fwnode_...
>>
>> instead ?
>>
>> Also what is the expectation here ? Are these properties a MUST for
>> TPDM ?
>
> The TPDM must have one of the element size property. As long as one
Please add a comment in the function. Someone else might try to "fix"
it otherwise.
Suzuki
>
> can be found, this TPDM configuration can be considered valid. So this
>
> function will return 0 if one of the element size property is found.
>
>
> Best,
>
> Tao
>
>>
>>> if (rc)
>>> dev_warn_once(&csdev->dev,
>>> - "Failed to read TPDM DSB Element size: %d\n", rc);
>>> + "Failed to read TPDM Element size: %d\n", rc);
>>> - return size;
>>> + return rc;
>>> }
>>> /*
>>> @@ -56,11 +86,12 @@ static int tpdm_read_dsb_element_size(struct
>>> coresight_device *csdev)
>>> * Parameter "inport" is used to pass in the input port number
>>> * of TPDA, and it is set to -1 in the recursize call.
>>> */
>>> -static int tpda_get_element_size(struct coresight_device *csdev,
>>> +static int tpda_get_element_size(struct tpda_drvdata *drvdata,
>>> + struct coresight_device *csdev,
>>> int inport)
>>> {
>>> - int dsb_size = -ENOENT;
>>> - int i, size;
>>> + int rc = 0;
>>> + int i;
>>> struct coresight_device *in;
>>> for (i = 0; i < csdev->pdata->nr_inconns; i++) {
>>> @@ -74,25 +105,21 @@ static int tpda_get_element_size(struct
>>> coresight_device *csdev,
>>> continue;
>>> if (coresight_device_is_tpdm(in)) {
>>> - size = tpdm_read_dsb_element_size(in);
>>> + if ((drvdata->dsb_esize) || (drvdata->cmb_esize))
>>> + return -EEXIST;
>>> + rc = tpdm_read_element_size(drvdata, in);
>>> + if (rc)
>>> + return rc;
>>> } else {
>>> /* Recurse down the path */
>>> - size = tpda_get_element_size(in, -1);
>>> - }
>>> -
>>> - if (size < 0)
>>> - return size;
>>> -
>>> - if (dsb_size < 0) {
>>> - /* Found a size, save it. */
>>> - dsb_size = size;
>>> - } else {
>>> - /* Found duplicate TPDMs */
>>> - return -EEXIST;
>>> + rc = tpda_get_element_size(drvdata, in, -1);
>>> + if (rc)
>>> + return rc;
>>> }
>>> }
>>> - return dsb_size;
>>> +
>>> + return rc;
>>> }
>>> /* Settings pre enabling port control register */
>>> @@ -109,7 +136,7 @@ static void tpda_enable_pre_port(struct
>>> tpda_drvdata *drvdata)
>>> static int tpda_enable_port(struct tpda_drvdata *drvdata, int port)
>>> {
>>> u32 val;
>>> - int size;
>>> + int rc;
>>> val = readl_relaxed(drvdata->base + TPDA_Pn_CR(port));
>>> /*
>>> @@ -117,29 +144,21 @@ static int tpda_enable_port(struct tpda_drvdata
>>> *drvdata, int port)
>>> * Set the bit to 0 if the size is 32
>>> * Set the bit to 1 if the size is 64
>>> */
>>> - size = tpda_get_element_size(drvdata->csdev, port);
>>> - switch (size) {
>>> - case 32:
>>> - val &= ~TPDA_Pn_CR_DSBSIZE;
>>> - break;
>>> - case 64:
>>> - val |= TPDA_Pn_CR_DSBSIZE;
>>> - break;
>>> - case 0:
>>> - return -EEXIST;
>>> - case -EEXIST:
>>> + tpdm_clear_element_size(drvdata->csdev);
>>> + rc = tpda_get_element_size(drvdata, drvdata->csdev, port);
>>> + if (!rc && ((drvdata->dsb_esize) || (drvdata->cmb_esize))) {
>>> + tpda_set_element_size(drvdata, &val);
>>> + /* Enable the port */
>>> + val |= TPDA_Pn_CR_ENA;
>>> + writel_relaxed(val, drvdata->base + TPDA_Pn_CR(port));
>>> + } else if (rc == -EEXIST)
>>> dev_warn_once(&drvdata->csdev->dev,
>>> - "Detected multiple TPDMs on port %d", -EEXIST);
>>> - return -EEXIST;
>>> - default:
>>> - return -EINVAL;
>>> - }
>>> -
>>> - /* Enable the port */
>>> - val |= TPDA_Pn_CR_ENA;
>>> - writel_relaxed(val, drvdata->base + TPDA_Pn_CR(port));
>>> + "Detected multiple TPDMs on port %d", -EEXIST);
>>> + else
>>> + dev_warn_once(&drvdata->csdev->dev,
>>> + "Didn't find TPDM elem size");
>>
>> "element size"
>>
>>> - return 0;
>>> + return rc;
>>> }
>>> static int __tpda_enable(struct tpda_drvdata *drvdata, int port)
>>> diff --git a/drivers/hwtracing/coresight/coresight-tpda.h
>>> b/drivers/hwtracing/coresight/coresight-tpda.h
>>> index b3b38fd41b64..29164fd9711f 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 CMB data set element size bit */
>>> +#define TPDA_Pn_CR_CMBSIZE GENMASK(7, 6)
>>> /* Aggregator port DSB data set element size bit */
>>> #define TPDA_Pn_CR_DSBSIZE BIT(8)
>>> @@ -25,6 +27,8 @@
>>> * @csdev: component vitals needed by the framework.
>>> * @spinlock: lock for the drvdata value.
>>> * @enable: enable status of the component.
>>> + * @dsb_esize Record the DSB element size.
>>> + * @cmb_esize Record the CMB element size.
>>> */
>>> struct tpda_drvdata {
>>> void __iomem *base;
>>> @@ -32,6 +36,8 @@ struct tpda_drvdata {
>>> struct coresight_device *csdev;
>>> spinlock_t spinlock;
>>> u8 atid;
>>> + u8 dsb_esize;
>>> + u8 cmb_esize;
>>> };
>>> #endif /* _CORESIGHT_CORESIGHT_TPDA_H */
>>
>> Suzuki
>>
>>
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