[PATCH v7 08/13] coresight-tpdm: Add node to set dsb programming mode
Suzuki K Poulose
suzuki.poulose at arm.com
Mon Aug 7 03:00:25 PDT 2023
On 25/07/2023 08:15, 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 0b7b4ad..2a82cd0 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 6.5
> +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.
(RW) ...
> +
> + 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 62efc18..c38760b 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>
> @@ -42,6 +43,32 @@ 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 tpdm_enable_dsb(struct tpdm_drvdata *drvdata)
> {
> u32 val;
> @@ -55,6 +82,12 @@ 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);
Couldn't all of them be combined to a single function, as they
operate on a single value to be written ?
set_dsb_mode(drvdata, &val);
> /* Set trigger type */
> if (drvdata->dsb->trig_type)
> val |= TPDM_DSB_CR_TRIG_TYPE;
> @@ -241,6 +274,34 @@ 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);
It is u32 anyways, hence why not :
(buf, "%x\n", 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;
> +
Is it not an error :
if (val & ~TPDM_DSB_MODE_MASK) ?
> + spin_lock(&drvdata->spinlock);
> + drvdata->dsb->mode = val & TPDM_DSB_MODE_MASK;
> + 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)
> {
> @@ -312,6 +373,7 @@ 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 92c34cd..49fffb1 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))
What is the difference between MODE_TEST ^ and the TEST_MODE ( below ).
Please could we have clear naming conventions ?
> +/* Performance mode */
> +#define TPDM_DSB_MODE_PERF BIT(3)
> +/* High performance mode */
> +#define TPDM_DSB_MODE_HPBYTESEL(val) (val & GENMASK(8, 4))
> +#define TPDM_DSB_MODE_MASK GENMASK(8, 0)
> +#define TPDM_DSB_TEST_MODE GENMASK(10, 9)
> +#define TPDM_DSB_HPSEL GENMASK(6, 2)
Ah, I read it again and these two are really TPDM_DSB_CR_x and
1) Must be defined as such (to avoid any confusion as above)
2) And defined closer to the other value defintions for the registers ?
Suzuki
> +
> /* TPDM integration test registers */
> #define TPDM_ITATBCNTRL (0xEF0)
> #define TPDM_ITCNTRL (0xF00)
> @@ -48,10 +62,12 @@
>
> /**
> * struct dsb_dataset - specifics associated to dsb dataset
> + * @mode: DSB programming mode
> * @trig_ts: Enable/Disable trigger timestamp.
> * @trig_type: Enable/Disable trigger type.
> */
> struct dsb_dataset {
> + u32 mode;
> bool trig_ts;
> bool trig_type;
> };
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