Re: [PATCH v3 6/8] coresight-tpdm: Add timestamp control register support for the CMB
From: Suzuki K Poulose
Date: Sat Dec 30 2023 - 04:40:09 EST
On 25/12/2023 01:55, Tao Zhang wrote:
On 12/20/2023 7:07 PM, Suzuki K Poulose wrote:
On 20/12/2023 09:51, Tao Zhang wrote:
On 12/19/2023 9:51 PM, Suzuki K Poulose wrote:
On 19/12/2023 02:43, Tao Zhang wrote:
On 12/18/2023 6:46 PM, Suzuki K Poulose wrote:
On 21/11/2023 02:24, Tao Zhang wrote:
CMB_TIER register is CMB subunit timestamp insertion enable
register.
Bit 0 is PATT_TSENAB bit. Set this bit to 1 to request a timestamp
following a CMB interface pattern match. Bit 1 is XTRIG_TSENAB bit.
Set this bit to 1 to request a timestamp following a CMB CTI
timestamp
request. Bit 2 is TS_ALL bit. Set this bit to 1 to request timestamp
for all packets.
Reviewed-by: James Clark <james.clark@xxxxxxx>
Signed-off-by: Tao Zhang <quic_taozha@xxxxxxxxxxx>
Signed-off-by: Jinlong Mao <quic_jinlmao@xxxxxxxxxxx>
---
.../testing/sysfs-bus-coresight-devices-tpdm | 35 ++++++
drivers/hwtracing/coresight/coresight-tpdm.c | 116
+++++++++++++++++-
drivers/hwtracing/coresight/coresight-tpdm.h | 14 +++
3 files changed, 162 insertions(+), 3 deletions(-)
diff --git
a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
index 53662ce7c2d0..e0b77107be13 100644
--- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
@@ -214,3 +214,38 @@ KernelVersion 6.7
Contact: Jinlong Mao (QUIC) <quic_jinlmao@xxxxxxxxxxx>, Tao
Zhang (QUIC) <quic_taozha@xxxxxxxxxxx>
Description:
(RW) Set/Get the mask of the pattern for the CMB
subunit TPDM.
+
+What: /sys/bus/coresight/devices/<tpdm-name>/cmb_patt/enable_ts
+Date: September 2023
+KernelVersion 6.7
+Contact: Jinlong Mao (QUIC) <quic_jinlmao@xxxxxxxxxxx>, Tao
Zhang (QUIC) <quic_taozha@xxxxxxxxxxx>
+Description:
+ (Write) Set the pattern timestamp of CMB tpdm. Read
+ the pattern timestamp of CMB tpdm.
+
+ Accepts only one of the 2 values - 0 or 1.
+ 0 : Disable CMB pattern timestamp.
+ 1 : Enable CMB pattern timestamp.
+
+What: /sys/bus/coresight/devices/<tpdm-name>/cmb_trig_ts
+Date: September 2023
+KernelVersion 6.7
+Contact: Jinlong Mao (QUIC) <quic_jinlmao@xxxxxxxxxxx>, Tao
Zhang (QUIC) <quic_taozha@xxxxxxxxxxx>
+Description:
+ (RW) Set/Get the trigger timestamp of the CMB for tpdm.
+
+ Accepts only one of the 2 values - 0 or 1.
+ 0 : Set the CMB trigger type to false
+ 1 : Set the CMB trigger type to true
+
+What: /sys/bus/coresight/devices/<tpdm-name>/cmb_ts_all
+Date: September 2023
+KernelVersion 6.7
+Contact: Jinlong Mao (QUIC) <quic_jinlmao@xxxxxxxxxxx>, Tao
Zhang (QUIC) <quic_taozha@xxxxxxxxxxx>
+Description:
+ (RW) Read or write the status of timestamp upon all
interface.
+ Only value 0 and 1 can be written to this node. Set
this node to 1 to requeset
+ timestamp to all trace packet.
+ Accepts only one of the 2 values - 0 or 1.
+ 0 : Disable the timestamp of all trace packets.
+ 1 : Enable the timestamp of all trace packets.
diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c
b/drivers/hwtracing/coresight/coresight-tpdm.c
index 894d4309f1c7..f6cda5616e84 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.c
+++ b/drivers/hwtracing/coresight/coresight-tpdm.c
@@ -331,6 +331,36 @@ static void tpdm_enable_dsb(struct
tpdm_drvdata *drvdata)
writel_relaxed(val, drvdata->base + TPDM_DSB_CR);
}
+static void set_cmb_tier(struct tpdm_drvdata *drvdata)
+{
+ u32 val;
+
+ val = readl_relaxed(drvdata->base + TPDM_CMB_TIER);
+
+ /* Clear all relevant fields */
+ val &= ~(TPDM_CMB_TIER_PATT_TSENAB | TPDM_CMB_TIER_TS_ALL |
+ TPDM_CMB_TIER_XTRIG_TSENAB);
+
+ /* Set pattern timestamp type and enablement */
+ if (drvdata->cmb->patt_ts)
+ val |= TPDM_CMB_TIER_PATT_TSENAB;
-- cut --
+ else
+ val &= ~TPDM_CMB_TIER_PATT_TSENAB;
All the else cases in this function are superfluous. Please remove
all
of them.
I will update this in the next patch.
+
+ /* Set trigger timestamp */
+ if (drvdata->cmb->trig_ts)
+ val |= TPDM_CMB_TIER_XTRIG_TSENAB;
+ else
+ val &= ~TPDM_CMB_TIER_XTRIG_TSENAB;
+
+ /* Set all timestamp enablement*/
+ if (drvdata->cmb->ts_all)
+ val |= TPDM_CMB_TIER_TS_ALL;
+ else
+ val &= ~TPDM_CMB_TIER_TS_ALL;
+ writel_relaxed(val, drvdata->base + TPDM_CMB_TIER);
+}
+
static void tpdm_enable_cmb(struct tpdm_drvdata *drvdata)
{
u32 val, i;
@@ -347,6 +377,8 @@ static void tpdm_enable_cmb(struct
tpdm_drvdata *drvdata)
drvdata->base + TPDM_CMB_XPMR(i));
}
+ set_cmb_tier(drvdata);
+
val = readl_relaxed(drvdata->base + TPDM_CMB_CR);
/*
* Set to 0 for continuous CMB collection mode,
@@ -695,9 +727,17 @@ static ssize_t enable_ts_show(struct device
*dev,
char *buf)
{
struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ ssize_t size = 0;
- return sysfs_emit(buf, "%u\n",
- (unsigned int)drvdata->dsb->patt_ts);
+ if (tpdm_has_dsb_dataset(drvdata))
+ size = sysfs_emit(buf, "%u\n",
+ (unsigned int)drvdata->dsb->patt_ts);
+
+ if (tpdm_has_cmb_dataset(drvdata))
+ size = sysfs_emit(buf, "%u\n",
+ (unsigned int)drvdata->cmb->patt_ts);
Why does this need to show two values ? This must only show ONE
value.
How you deduce that might be based on the availability of the feature
set. Or store the TS value in the drvdata and use that instead for
controlling CMB/DSB.
Since both of CMB/DSB need to have "enable_ts" SysFs file, can I
separate them
The question really is, do we need fine grained control. i.e.,
enable TS for DSB but not for CMB or vice versa.
I am not an expert on the usage scenario of the same. So, if you/Qcomm
thinks the users need separate, fine grained control for timestamp
for the DSB and CMB, then yes, follow your recommendation below.
i.e., tpdm.../dsb_patt/enable_ts
as "enable_dsb_ts" and "enable_cmb_ts"? The path will be like below.
tpdm0/dsb_patt/enable_dsb_ts
You don't need enable_dsb_ts. It could be "enable_ts"
tpdm1/cmb_patt/enable_cmb_ts
Is this design appropriate?
Otherwise, stick to single enable_ts : which enables the ts for both
CMB/DSB. And it only ever show one value : 0 (TS is disabled for both
CMB/DSB) 1 : TS enabled for both.
We have a very special case, such as the TPDM supporting both CMB and
DSB datasets. Although this case is very rare, it still exists.
Can I use the data bit to instruct whether timestamp is enabled for
CMB/DSB or not? For example,
size = sysfs_emit(buf, "%u\n",
(unsigned int)(drvdata->dsb->patt_ts << 1 |
drvdata->cmb->patt_ts));
Thus, this value can instruct the following situations.
0 - TS is disabled for both CMB/DSB
1 - TS is enabled for CMB
2 - TS is enabled for DSB
3 - TS is enabled for both
Is this approach acceptable?
No, please stick to separate controls for TS. Do not complicate
the user interface.
i.e.,
tpdm0/dsb_patt/enable_ts
tpdm0/cmb_patt/enable_ts
We need to be able to control/show dsb and cmb timestamp enablement
independently.
Can we achieve this requirement if we use a sysfs file with the same name?
They are independent and in their respective directory (group) for CMB
and DSB. What am I missing ?
e.g., if you want to enable TS for DSB, you do :
$ echo 1 > dsb_patt/enable_ts
And that only works for DSB not for CMB.
Suzuki
I'm not able to find a good way to achieve it. Do you have any
suggestions for this?
Best,
Tao
Suzuki
Best,
Tao
Suzuki
Also, the sysfs documentation needs update, if this is going to
control the CMB.
Sure. I will update the SysFs documentation according to the
modification in the
next patch series.
Best,
Tao
Suzuki
+
+ return size;
}
/*
@@ -715,8 +755,13 @@ static ssize_t enable_ts_store(struct device
*dev,
return -EINVAL;
spin_lock(&drvdata->spinlock);
- drvdata->dsb->patt_ts = !!val;
+ if (tpdm_has_dsb_dataset(drvdata))
+ drvdata->dsb->patt_ts = !!val;
+
+ if (tpdm_has_cmb_dataset(drvdata))
+ drvdata->cmb->patt_ts = !!val;
spin_unlock(&drvdata->spinlock);
+
return size;
}
static DEVICE_ATTR_RW(enable_ts);
@@ -851,6 +896,68 @@ static ssize_t cmb_mode_store(struct device
*dev,
}
static DEVICE_ATTR_RW(cmb_mode);
+static ssize_t cmb_ts_all_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ return sysfs_emit(buf, "%u\n",
+ (unsigned int)drvdata->cmb->ts_all);
+}
+
+static ssize_t cmb_ts_all_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 & ~1UL))
+ return -EINVAL;
+
+ spin_lock(&drvdata->spinlock);
+ if (val)
+ drvdata->cmb->ts_all = true;
+ else
+ drvdata->cmb->ts_all = false;
+ spin_unlock(&drvdata->spinlock);
+ return size;
+}
+static DEVICE_ATTR_RW(cmb_ts_all);
+
+static ssize_t cmb_trig_ts_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ return sysfs_emit(buf, "%u\n",
+ (unsigned int)drvdata->cmb->trig_ts);
+}
+
+static ssize_t cmb_trig_ts_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 & ~1UL))
+ return -EINVAL;
+
+ spin_lock(&drvdata->spinlock);
+ if (val)
+ drvdata->cmb->trig_ts = true;
+ else
+ drvdata->cmb->trig_ts = false;
+ spin_unlock(&drvdata->spinlock);
+ return size;
+}
+static DEVICE_ATTR_RW(cmb_trig_ts);
+
static struct attribute *tpdm_dsb_edge_attrs[] = {
&dev_attr_ctrl_idx.attr,
&dev_attr_ctrl_val.attr,
@@ -973,6 +1080,7 @@ static struct attribute
*tpdm_cmb_patt_attrs[] = {
CMB_PATT_ATTR(1),
CMB_PATT_MASK_ATTR(0),
CMB_PATT_MASK_ATTR(1),
+ &dev_attr_enable_ts.attr,
NULL,
};
@@ -985,6 +1093,8 @@ static struct attribute *tpdm_dsb_attrs[] = {
static struct attribute *tpdm_cmb_attrs[] = {
&dev_attr_cmb_mode.attr,
+ &dev_attr_cmb_ts_all.attr,
+ &dev_attr_cmb_trig_ts.attr,
NULL,
};
diff --git a/drivers/hwtracing/coresight/coresight-tpdm.h
b/drivers/hwtracing/coresight/coresight-tpdm.h
index e90d008c1cb2..65b7ca6c4077 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.h
+++ b/drivers/hwtracing/coresight/coresight-tpdm.h
@@ -11,6 +11,8 @@
/* CMB Subunit Registers */
#define TPDM_CMB_CR (0xA00)
+/*CMB subunit timestamp insertion enable register*/
+#define TPDM_CMB_TIER (0xA04)
/*CMB subunit timestamp pattern registers*/
#define TPDM_CMB_TPR(n) (0xA08 + (n * 4))
/*CMB subunit timestamp pattern mask registers*/
@@ -24,6 +26,12 @@
#define TPDM_CMB_CR_ENA BIT(0)
/* Trace collection mode for CMB subunit */
#define TPDM_CMB_CR_MODE BIT(1)
+/* Timestamp control for pattern match */
+#define TPDM_CMB_TIER_PATT_TSENAB BIT(0)
+/* CMB CTI timestamp request */
+#define TPDM_CMB_TIER_XTRIG_TSENAB BIT(1)
+/* For timestamp fo all trace */
+#define TPDM_CMB_TIER_TS_ALL BIT(2)
/*Patten register number*/
#define TPDM_CMB_MAX_PATT 2
@@ -217,6 +225,9 @@ struct dsb_dataset {
* @patt_mask: Save value for pattern mask
* @trig_patt: Save value for trigger pattern
* @trig_patt_mask: Save value for trigger pattern mask
+ * @patt_ts: Indicates if pattern match for timestamp
is enabled.
+ * @trig_ts: Indicates if CTI trigger for timestamp is
enabled.
+ * @ts_all: Indicates if timestamp is enabled for all
packets.
*/
struct cmb_dataset {
u32 trace_mode;
@@ -224,6 +235,9 @@ struct cmb_dataset {
u32 patt_mask[TPDM_CMB_MAX_PATT];
u32 trig_patt[TPDM_CMB_MAX_PATT];
u32 trig_patt_mask[TPDM_CMB_MAX_PATT];
+ bool patt_ts;
+ bool trig_ts;
+ bool ts_all;
};
/**
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