[PATCH 2/3] coresight: etb10: splitting sysFS "status" entry
From: Mathieu Poirier
Date: Tue Mar 08 2016 - 22:49:15 EST
The sysFS "status" entry conveys a wealth of information about
the status of the HW but goes agains the sysFS rule of one topic
per file.
This patch rectifies the situation by adding read-only entries for
each of the field formaly displayed by "status". The ABI
documentation is kept up to date.
An error message with questionnable relevance is also removed to
keep checkpatch.pl happy.
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
---
.../ABI/testing/sysfs-bus-coresight-devices-etb10 | 69 +++++++++++++++--
drivers/hwtracing/coresight/coresight-etb10.c | 86 ++++++++++------------
2 files changed, 101 insertions(+), 54 deletions(-)
diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etb10 b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etb10
index 4b8d6ec92e2b..b5f526081711 100644
--- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etb10
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etb10
@@ -6,13 +6,6 @@ Description: (RW) Add/remove a sink from a trace path. There can be multiple
source for a single sink.
ex: echo 1 > /sys/bus/coresight/devices/20010000.etb/enable_sink
-What: /sys/bus/coresight/devices/<memory_map>.etb/status
-Date: November 2014
-KernelVersion: 3.19
-Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
-Description: (R) List various control and status registers. The specific
- layout and content is driver specific.
-
What: /sys/bus/coresight/devices/<memory_map>.etb/trigger_cntr
Date: November 2014
KernelVersion: 3.19
@@ -22,3 +15,65 @@ Description: (RW) Disables write access to the Trace RAM by stopping the
following the trigger event. The number of 32-bit words written
into the Trace RAM following the trigger event is equal to the
value stored in this register+1 (from ARM ETB-TRM).
+
+What: /sys/bus/coresight/devices/<memory_map>.etb/mgmt/rdp
+Date: March 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (R) Defines the depth, in words, of the trace RAM in powers of
+ 2. The value is read directly from HW register RDP, 0x004.
+
+What: /sys/bus/coresight/devices/<memory_map>.etb/mgmt/sts
+Date: March 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (R) Shows the value held by the ETB status register. The value
+ is read directly from HW register STS, 0x00C.
+
+What: /sys/bus/coresight/devices/<memory_map>.etb/mgmt/rrp
+Date: March 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (R) Shows the value held by the ETB RAM Read Pointer register
+ that is used to read entries from the Trace RAM over the APB
+ interface. The value is read directly from HW register RRP,
+ 0x014.
+
+What: /sys/bus/coresight/devices/<memory_map>.etb/mgmt/rwp
+Date: March 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (R) Shows the value held by the ETB RAM Write Pointer register
+ that is used to sets the write pointer to write entries from
+ the CoreSight bus into the Trace RAM. The value is read directly
+ from HW register RWP, 0x018.
+
+What: /sys/bus/coresight/devices/<memory_map>.etb/mgmt/trg
+Date: March 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (R) Similar to "trigger_cntr" above except that this value is
+ read directly from HW register TRG, 0x01C.
+
+What: /sys/bus/coresight/devices/<memory_map>.etb/mgmt/ctl
+Date: March 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (R) Shows the value held by the ETB Control register. The value
+ is read directly from HW register CTL, 0x020.
+
+What: /sys/bus/coresight/devices/<memory_map>.etb/mgmt/ffsr
+Date: March 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (R) Shows the value held by the ETB Formatter and Flush Status
+ register. The value is read directly from HW register FFSR,
+ 0x300.
+
+What: /sys/bus/coresight/devices/<memory_map>.etb/mgmt/ffcr
+Date: March 2016
+KernelVersion: 4.7
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (R) Shows the value held by the ETB Formatter and Flush Control
+ register. The value is read directly from HW register FFCR,
+ 0x304.
diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index a2eb6bdeaafa..bf7686fa1f1f 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -578,47 +578,29 @@ static const struct file_operations etb_fops = {
.llseek = no_llseek,
};
-static ssize_t status_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- unsigned long flags;
- u32 etb_rdr, etb_sr, etb_rrp, etb_rwp;
- u32 etb_trg, etb_cr, etb_ffsr, etb_ffcr;
- struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent);
-
- pm_runtime_get_sync(drvdata->dev);
- spin_lock_irqsave(&drvdata->spinlock, flags);
- CS_UNLOCK(drvdata->base);
-
- etb_rdr = readl_relaxed(drvdata->base + ETB_RAM_DEPTH_REG);
- etb_sr = readl_relaxed(drvdata->base + ETB_STATUS_REG);
- etb_rrp = readl_relaxed(drvdata->base + ETB_RAM_READ_POINTER);
- etb_rwp = readl_relaxed(drvdata->base + ETB_RAM_WRITE_POINTER);
- etb_trg = readl_relaxed(drvdata->base + ETB_TRG);
- etb_cr = readl_relaxed(drvdata->base + ETB_CTL_REG);
- etb_ffsr = readl_relaxed(drvdata->base + ETB_FFSR);
- etb_ffcr = readl_relaxed(drvdata->base + ETB_FFCR);
-
- CS_LOCK(drvdata->base);
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
-
- pm_runtime_put(drvdata->dev);
-
- return sprintf(buf,
- "Depth:\t\t0x%x\n"
- "Status:\t\t0x%x\n"
- "RAM read ptr:\t0x%x\n"
- "RAM wrt ptr:\t0x%x\n"
- "Trigger cnt:\t0x%x\n"
- "Control:\t0x%x\n"
- "Flush status:\t0x%x\n"
- "Flush ctrl:\t0x%x\n",
- etb_rdr, etb_sr, etb_rrp, etb_rwp,
- etb_trg, etb_cr, etb_ffsr, etb_ffcr);
-
- return -EINVAL;
-}
-static DEVICE_ATTR_RO(status);
+#define coresight_etb10_simple_func(name, offset) \
+ coresight_simple_func(struct etb_drvdata, name, offset)
+
+coresight_etb10_simple_func(rdp, ETB_RAM_DEPTH_REG);
+coresight_etb10_simple_func(sts, ETB_STATUS_REG);
+coresight_etb10_simple_func(rrp, ETB_RAM_READ_POINTER);
+coresight_etb10_simple_func(rwp, ETB_RAM_WRITE_POINTER);
+coresight_etb10_simple_func(trg, ETB_TRG);
+coresight_etb10_simple_func(ctl, ETB_CTL_REG);
+coresight_etb10_simple_func(ffsr, ETB_FFSR);
+coresight_etb10_simple_func(ffcr, ETB_FFCR);
+
+static struct attribute *coresight_etb_mgmt_attrs[] = {
+ &dev_attr_rdp.attr,
+ &dev_attr_sts.attr,
+ &dev_attr_rrp.attr,
+ &dev_attr_rwp.attr,
+ &dev_attr_trg.attr,
+ &dev_attr_ctl.attr,
+ &dev_attr_ffsr.attr,
+ &dev_attr_ffcr.attr,
+ NULL,
+};
static ssize_t trigger_cntr_show(struct device *dev,
struct device_attribute *attr, char *buf)
@@ -648,10 +630,23 @@ static DEVICE_ATTR_RW(trigger_cntr);
static struct attribute *coresight_etb_attrs[] = {
&dev_attr_trigger_cntr.attr,
- &dev_attr_status.attr,
NULL,
};
-ATTRIBUTE_GROUPS(coresight_etb);
+
+static const struct attribute_group coresight_etb_group = {
+ .attrs = coresight_etb_attrs,
+};
+
+static const struct attribute_group coresight_etb_mgmt_group = {
+ .attrs = coresight_etb_mgmt_attrs,
+ .name = "mgmt",
+};
+
+const struct attribute_group *coresight_etb_groups[] = {
+ &coresight_etb_group,
+ &coresight_etb_mgmt_group,
+ NULL,
+};
static int etb_probe(struct amba_device *adev, const struct amba_id *id)
{
@@ -701,11 +696,8 @@ static int etb_probe(struct amba_device *adev, const struct amba_id *id)
drvdata->buf = devm_kzalloc(dev,
drvdata->buffer_depth * 4, GFP_KERNEL);
- if (!drvdata->buf) {
- dev_err(dev, "Failed to allocate %u bytes for buffer data\n",
- drvdata->buffer_depth * 4);
+ if (!drvdata->buf)
return -ENOMEM;
- }
desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
if (!desc)
--
2.1.4