[PATCH v4 06/11] coresight-tpdm: Add node to set dsb programming mode
Suzuki K Poulose
suzuki.poulose at arm.com
Fri Jun 2 01:25:25 PDT 2023
On 02/06/2023 03:58, Tao Zhang wrote:
>
> On 6/1/2023 5:23 PM, Suzuki K Poulose wrote:
>> On 27/04/2023 10:00, Tao Zhang wrote:
>>> Add node to set and show programming mode for TPDM DSB subunit.
>>> Once the DSB programming mode is set, it will be written to the
>>> register DSB_CR.
>>>
>>> Signed-off-by: Tao Zhang <quic_taozha at quicinc.com>
>>> ---
>>> .../ABI/testing/sysfs-bus-coresight-devices-tpdm | 15 ++++++
>>> drivers/hwtracing/coresight/coresight-tpdm.c | 62
>>> ++++++++++++++++++++++
>>> drivers/hwtracing/coresight/coresight-tpdm.h | 16 ++++++
>>> 3 files changed, 93 insertions(+)
>>>
>>> diff --git
>>> a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>>> b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>>> index 77e67f2..348e167 100644
>>> --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>>> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
>>> @@ -45,3 +45,18 @@ Description:
>>> Accepts only one of the 2 values - 0 or 1.
>>> 0 : Set the DSB trigger type to false
>>> 1 : Set the DSB trigger type to true
>>> +
>>> +What: /sys/bus/coresight/devices/<tpdm-name>/dsb_mode
>>> +Date: March 2023
>>> +KernelVersion 6.3
>>> +Contact: Jinlong Mao (QUIC) <quic_jinlmao at quicinc.com>, Tao Zhang
>>> (QUIC) <quic_taozha at quicinc.com>
>>> +Description:
>>> + (Write) Set the mode of DSB tpdm. Read the mode of DSB
>>> + tpdm.
>>> +
>>> + Accepts the value needs to be greater than 0. What data
>>> + bits do is listed below.
>>> + Bit[0:1] : Test mode control bit for choosing the inputs.
>>> + Bit[3] : Set to 0 for low performance mode.
>>> + Set to 1 for high performance mode.
>>> + Bit[4:8] : Select byte lane for high performance mode.
>>> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c
>>> b/drivers/hwtracing/coresight/coresight-tpdm.c
>>> index 14f4352..1bacaa5 100644
>>> --- a/drivers/hwtracing/coresight/coresight-tpdm.c
>>> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
>>> @@ -4,6 +4,7 @@
>>> */
>>> #include <linux/amba/bus.h>
>>> +#include <linux/bitfield.h>
>>> #include <linux/bitmap.h>
>>> #include <linux/coresight.h>
>>> #include <linux/coresight-pmu.h>
>>> @@ -43,6 +44,32 @@ static void tpdm_reset_datasets(struct
>>> tpdm_drvdata *drvdata)
>>> }
>>> }
>>> +static void set_dsb_test_mode(struct tpdm_drvdata *drvdata, u32 *val)
>>> +{
>>> + u32 mode;
>>> +
>>> + mode = TPDM_DSB_MODE_TEST(drvdata->dsb->mode);
>>> + *val &= ~TPDM_DSB_TEST_MODE;
>>> + *val |= FIELD_PREP(TPDM_DSB_TEST_MODE, mode);
>>> +}
>>> +
>>> +static void set_dsb_hpsel_mode(struct tpdm_drvdata *drvdata, u32 *val)
>>> +{
>>> + u32 mode;
>>> +
>>> + mode = TPDM_DSB_MODE_HPBYTESEL(drvdata->dsb->mode);
>>> + *val &= ~TPDM_DSB_HPSEL;
>>> + *val |= FIELD_PREP(TPDM_DSB_HPSEL, mode);
>>> +}
>>> +
>>> +static void set_dsb_perf_mode(struct tpdm_drvdata *drvdata, u32 *val)
>>> +{
>>> + if (drvdata->dsb->mode & TPDM_DSB_MODE_PERF)
>>> + *val |= TPDM_DSB_CR_MODE;
>>> + else
>>> + *val &= ~TPDM_DSB_CR_MODE;
>>> +}
>>> +
>>> static void set_trigger_type(struct tpdm_drvdata *drvdata, u32 *val)
>>> {
>>> if (drvdata->dsb->trig_type)
>>> @@ -64,6 +91,12 @@ static void tpdm_enable_dsb(struct tpdm_drvdata
>>> *drvdata)
>>> writel_relaxed(val, drvdata->base + TPDM_DSB_TIER);
>>> val = readl_relaxed(drvdata->base + TPDM_DSB_CR);
>>> + /* Set the test accurate mode */
>>> + set_dsb_test_mode(drvdata, &val);
>>> + /* Set the byte lane for high-performance mode */
>>> + set_dsb_hpsel_mode(drvdata, &val);
>>> + /* Set the performance mode */
>>> + set_dsb_perf_mode(drvdata, &val);
>>> /* Set trigger type */
>>> set_trigger_type(drvdata, &val);
>>> /* Set the enable bit of DSB control register to 1 */
>>> @@ -252,6 +285,34 @@ static struct attribute_group tpdm_attr_grp = {
>>> .attrs = tpdm_attrs,
>>> };
>>> +static ssize_t dsb_mode_show(struct device *dev,
>>> + struct device_attribute *attr,
>>> + char *buf)
>>> +{
>>> + struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>>> +
>>> + return sysfs_emit(buf, "%lx\n",
>>> + (unsigned long)drvdata->dsb->mode);
>>> +}
>>> +
>>> +static ssize_t dsb_mode_store(struct device *dev,
>>> + struct device_attribute *attr,
>>> + const char *buf,
>>> + size_t size)
>>> +{
>>> + struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
>>> + unsigned long val;
>>> +
>>> + if ((kstrtoul(buf, 0, &val)) || val < 0)
>>> + return -EINVAL;
>>> +
>>> + spin_lock(&drvdata->spinlock);
>>> + drvdata->dsb->mode = val & TPDM_MODE_ALL;
>>> + spin_unlock(&drvdata->spinlock);
>>> + return size;
>>> +}
>>> +static DEVICE_ATTR_RW(dsb_mode);
>>> +
>>> static ssize_t dsb_trig_type_show(struct device *dev,
>>> struct device_attribute *attr, char *buf)
>>> {
>>> @@ -323,6 +384,7 @@ static ssize_t dsb_trig_ts_store(struct device *dev,
>>> static DEVICE_ATTR_RW(dsb_trig_ts);
>>> static struct attribute *tpdm_dsb_attrs[] = {
>>> + &dev_attr_dsb_mode.attr,
>>> &dev_attr_dsb_trig_ts.attr,
>>> &dev_attr_dsb_trig_type.attr,
>>> NULL,
>>> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.h
>>> b/drivers/hwtracing/coresight/coresight-tpdm.h
>>> index 68f33bd..79df07e 100644
>>> --- a/drivers/hwtracing/coresight/coresight-tpdm.h
>>> +++ b/drivers/hwtracing/coresight/coresight-tpdm.h
>>> @@ -15,11 +15,25 @@
>>> /* Enable bit for DSB subunit */
>>> #define TPDM_DSB_CR_ENA BIT(0)
>>> +/* Enable bit for DSB subunit perfmance mode */
>>> +#define TPDM_DSB_CR_MODE BIT(1)
>>> /* Enable bit for DSB subunit trigger type */
>>> #define TPDM_DSB_CR_TRIG_TYPE BIT(12)
>>> +
>>> /* Enable bit for DSB subunit trigger timestamp */
>>> #define TPDM_DSB_TIER_XTRIG_TSENAB BIT(1)
>>> +/* DSB programming modes */
>>> +/* Test mode control bit*/
>>> +#define TPDM_DSB_MODE_TEST(val) (val & GENMASK(1, 0))
>>> +/* Perforceman mode */
>>
>> minor nit: typo ^^
> I will update this in the next patch series.
>>
>>> +#define TPDM_DSB_MODE_PERF BIT(3)
>>> +/* High performance mode */
>>> +#define TPDM_DSB_MODE_HPBYTESEL(val) (val & GENMASK(8, 4))
>>> +#define TPDM_MODE_ALL (0xFFFFFFF)
>>
>> GENMASK(27, 0) ?
>>
>> Also, why do we cover bits 27-0 ?
>
> The TPDM mode is only represented by [0:8]bits.
>
> Can I replace it with "#define TPDM_DSB_MODE(val) (VAL & GENMASK(8,
> 0))"?
#define TPDM_DSB_MODE_MASK GENMASK(8, 0) ?
Suzuki
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