[PATCH 5/5] ARM: etm: Configure data tracing

From: Arve HjÃnnevÃg
Date: Wed Feb 02 2011 - 21:55:53 EST


The old code enabled data tracing, but did not configure the
range. We now configure it to trace all data addresses by default,
and add a trace_data_range attribute to change the range or disable
data tracing.

Signed-off-by: Arve HjÃnnevÃg <arve@xxxxxxxxxxx>
---
arch/arm/include/asm/hardware/coresight.h | 10 +++-
arch/arm/kernel/etm.c | 76 +++++++++++++++++++++++++++-
2 files changed, 82 insertions(+), 4 deletions(-)

diff --git a/arch/arm/include/asm/hardware/coresight.h b/arch/arm/include/asm/hardware/coresight.h
index 7ecd793..b95a6f0 100644
--- a/arch/arm/include/asm/hardware/coresight.h
+++ b/arch/arm/include/asm/hardware/coresight.h
@@ -17,9 +17,11 @@
#define TRACER_ACCESSED_BIT 0
#define TRACER_RUNNING_BIT 1
#define TRACER_CYCLE_ACC_BIT 2
+#define TRACER_TRACE_DATA_BIT 3
#define TRACER_ACCESSED BIT(TRACER_ACCESSED_BIT)
#define TRACER_RUNNING BIT(TRACER_RUNNING_BIT)
#define TRACER_CYCLE_ACC BIT(TRACER_CYCLE_ACC_BIT)
+#define TRACER_TRACE_DATA BIT(TRACER_TRACE_DATA_BIT)

#define TRACER_TIMEOUT 10000

@@ -113,8 +115,14 @@
#define ETMR_TRACEENCTRL 0x24
#define ETMTE_INCLEXCL BIT(24)
#define ETMR_TRACEENEVT 0x20
+
+#define ETMR_VIEWDATAEVT 0x30
+#define ETMR_VIEWDATACTRL1 0x34
+#define ETMR_VIEWDATACTRL2 0x38
+#define ETMR_VIEWDATACTRL3 0x3c
+#define ETMVDC3_EXCLONLY (1 << 16)
+
#define ETMCTRL_OPTS (ETMCTRL_DO_CPRT | \
- ETMCTRL_DATA_DO_ADDR | \
ETMCTRL_BRANCH_OUTPUT | \
ETMCTRL_DO_CONTEXTID)

diff --git a/arch/arm/kernel/etm.c b/arch/arm/kernel/etm.c
index 6ff1004..ccd6d12 100644
--- a/arch/arm/kernel/etm.c
+++ b/arch/arm/kernel/etm.c
@@ -42,6 +42,8 @@ struct tracectx {
int etm_portsz;
unsigned long range_start;
unsigned long range_end;
+ unsigned long data_range_start;
+ unsigned long data_range_end;
struct device *dev;
struct clk *emu_clk;
struct mutex mutex;
@@ -83,8 +85,15 @@ static int etm_setup_address_range(struct tracectx *t, int n,
etm_writel(t, flags, ETMR_COMP_ACC_TYPE(n * 2 + 1));
etm_writel(t, end, ETMR_COMP_VAL(n * 2 + 1));

- flags = exclude ? ETMTE_INCLEXCL : 0;
- etm_writel(t, flags | (1 << n), ETMR_TRACEENCTRL);
+ if (data) {
+ flags = exclude ? ETMVDC3_EXCLONLY : 0;
+ if (exclude)
+ n += 8;
+ etm_writel(t, flags | BIT(n), ETMR_VIEWDATACTRL3);
+ } else {
+ flags = exclude ? ETMTE_INCLEXCL : 0;
+ etm_writel(t, flags | (1 << n), ETMR_TRACEENCTRL);
+ }

return 0;
}
@@ -107,6 +116,9 @@ static int trace_start(struct tracectx *t)
if (t->flags & TRACER_CYCLE_ACC)
v |= ETMCTRL_CYCLEACCURATE;

+ if (t->flags & TRACER_TRACE_DATA)
+ v |= ETMCTRL_DATA_DO_ADDR;
+
etm_unlock(t);

etm_writel(t, v, ETMR_CTRL);
@@ -129,6 +141,17 @@ static int trace_start(struct tracectx *t)
etm_writel(t, 0, ETMR_TRACESSCTRL);
etm_writel(t, 0x6f, ETMR_TRACEENEVT);

+ etm_writel(t, 0, ETMR_VIEWDATACTRL1);
+ etm_writel(t, 0, ETMR_VIEWDATACTRL2);
+
+ if (t->data_range_start || t->data_range_end)
+ etm_setup_address_range(t, 2, t->data_range_start,
+ t->data_range_end, 0, 1);
+ else
+ etm_writel(t, ETMVDC3_EXCLONLY, ETMR_VIEWDATACTRL3);
+
+ etm_writel(t, 0x6f, ETMR_VIEWDATAEVT);
+
v &= ~ETMCTRL_PROGRAM;
v |= ETMCTRL_PORTSEL;

@@ -570,6 +593,48 @@ static ssize_t trace_range_store(struct kobject *kobj,
static struct kobj_attribute trace_range_attr =
__ATTR(trace_range, 0644, trace_range_show, trace_range_store);

+static ssize_t trace_data_range_show(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ char *buf)
+{
+ unsigned long range_start;
+ u64 range_end;
+ mutex_lock(&tracer.mutex);
+ range_start = tracer.data_range_start;
+ range_end = tracer.data_range_end;
+ if (!range_end && (tracer.flags & TRACER_TRACE_DATA))
+ range_end = 0x100000000ULL;
+ mutex_unlock(&tracer.mutex);
+ return sprintf(buf, "%08lx %08llx\n", range_start, range_end);
+}
+
+static ssize_t trace_data_range_store(struct kobject *kobj,
+ struct kobj_attribute *attr,
+ const char *buf, size_t n)
+{
+ unsigned long range_start;
+ u64 range_end;
+
+ if (sscanf(buf, "%lx %llx", &range_start, &range_end) != 2)
+ return -EINVAL;
+
+ mutex_lock(&tracer.mutex);
+ tracer.data_range_start = range_start;
+ tracer.data_range_end = (unsigned long)range_end;
+ if (range_end)
+ tracer.flags |= TRACER_TRACE_DATA;
+ else
+ tracer.flags &= ~TRACER_TRACE_DATA;
+ mutex_unlock(&tracer.mutex);
+
+ return n;
+}
+
+
+static struct kobj_attribute trace_data_range_attr =
+ __ATTR(trace_data_range, 0644,
+ trace_data_range_show, trace_data_range_store);
+
static int __init etm_probe(struct amba_device *dev, struct amba_id *id)
{
struct tracectx *t = &tracer;
@@ -595,7 +660,7 @@ static int __init etm_probe(struct amba_device *dev, struct amba_id *id)

mutex_init(&t->mutex);
t->dev = &dev->dev;
- t->flags = TRACER_CYCLE_ACC;
+ t->flags = TRACER_CYCLE_ACC | TRACER_TRACE_DATA;
t->etm_portsz = 1;

etm_unlock(t);
@@ -625,6 +690,11 @@ static int __init etm_probe(struct amba_device *dev, struct amba_id *id)
if (ret)
dev_dbg(&dev->dev, "Failed to create trace_range in sysfs\n");

+ ret = sysfs_create_file(&dev->dev.kobj, &trace_data_range_attr.attr);
+ if (ret)
+ dev_dbg(&dev->dev,
+ "Failed to create trace_data_range in sysfs\n");
+
dev_dbg(t->dev, "ETM AMBA driver initialized.\n");

out:
--
1.7.3.1

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