ARM: etm: Add sysfs entry to disable branch_output flag

Change-Id: Ib91208a2c33621aa2d7bd9aa72bfbc670d9d5f1d
Signed-off-by: Arve Hjønnevåg <arve@android.com>

diff --git a/arch/arm/include/asm/hardware/coresight.h b/arch/arm/include/asm/hardware/coresight.h
index 47b7696845556291cae2fc2d13d4c091e548d9f5..727ba0f0d44b7decbc4db838f0935b14b7b55581 100644 (file)
--- a/arch/arm/include/asm/hardware/coresight.h
+++ b/arch/arm/include/asm/hardware/coresight.h
@@ -19,11 +19,13 @@
 #define TRACER_CYCLE_ACC_BIT   2
 #define TRACER_TRACE_DATA_BIT  3
 #define TRACER_TIMESTAMP_BIT   4
+#define TRACER_BRANCHOUTPUT_BIT        5
 #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_TIMESTAMP       BIT(TRACER_TIMESTAMP_BIT)
+#define TRACER_BRANCHOUTPUT    BIT(TRACER_BRANCHOUTPUT_BIT)
 
 #define TRACER_TIMEOUT 10000
 
@@ -126,8 +128,7 @@
 #define ETMR_VIEWDATACTRL3     0x3c
 #define ETMVDC3_EXCLONLY       BIT(16)
 
-#define ETMCTRL_OPTS           (ETMCTRL_DO_CPRT | \
-                               ETMCTRL_BRANCH_OUTPUT)
+#define ETMCTRL_OPTS           (ETMCTRL_DO_CPRT)
 
 #define ETMR_ID                        0x1e4
 #define ETMIDR_VERSION(x)      (((x) >> 4) & 0xff)

diff --git a/arch/arm/kernel/etm.c b/arch/arm/kernel/etm.c
index 9cba22d2047c8e2eb912ac8a3625d9d255a3d37b..ad1ee5790a0e490d155f6591a4caf0ff8d035fe6 100644 (file)
--- a/arch/arm/kernel/etm.c
+++ b/arch/arm/kernel/etm.c
@@ -114,6 +114,9 @@ static int trace_start_etm(struct tracectx *t, int id)
        if (t->flags & TRACER_CYCLE_ACC)
                v |= ETMCTRL_CYCLEACCURATE;
 
+       if (t->flags & TRACER_BRANCHOUTPUT)
+               v |= ETMCTRL_BRANCH_OUTPUT;
+
        if (t->flags & TRACER_TRACE_DATA)
                v |= ETMCTRL_DATA_DO_ADDR;
 
@@ -682,6 +685,36 @@ static struct kobj_attribute trace_contextid_size_attr =
        __ATTR(trace_contextid_size, 0644,
                trace_contextid_size_show, trace_contextid_size_store);
 
+static ssize_t trace_branch_output_show(struct kobject *kobj,
+                                       struct kobj_attribute *attr,
+                                       char *buf)
+{
+       return sprintf(buf, "%d\n", !!(tracer.flags & TRACER_BRANCHOUTPUT));
+}
+
+static ssize_t trace_branch_output_store(struct kobject *kobj,
+                                        struct kobj_attribute *attr,
+                                        const char *buf, size_t n)
+{
+       unsigned int branch_output;
+
+       if (sscanf(buf, "%u", &branch_output) != 1)
+               return -EINVAL;
+
+       mutex_lock(&tracer.mutex);
+       if (branch_output)
+               tracer.flags |= TRACER_BRANCHOUTPUT;
+       else
+               tracer.flags &= ~TRACER_BRANCHOUTPUT;
+       mutex_unlock(&tracer.mutex);
+
+       return n;
+}
+
+static struct kobj_attribute trace_branch_output_attr =
+       __ATTR(trace_branch_output, 0644,
+               trace_branch_output_show, trace_branch_output_store);
+
 static ssize_t trace_timestamp_show(struct kobject *kobj,
                                  struct kobj_attribute *attr,
                                  char *buf)
@@ -819,7 +852,7 @@ static int __devinit etm_probe(struct amba_device *dev, const struct amba_id *id
 
        amba_set_drvdata(dev, t->etm_regs[t->etm_regs_count]);
 
-       t->flags = TRACER_CYCLE_ACC | TRACER_TRACE_DATA;
+       t->flags = TRACER_CYCLE_ACC | TRACER_TRACE_DATA | TRACER_BRANCHOUTPUT;
        t->etm_portsz = 1;
        t->etm_contextid_size = 3;
 
@@ -860,6 +893,12 @@ static int __devinit etm_probe(struct amba_device *dev, const struct amba_id *id
                dev_dbg(&dev->dev,
                        "Failed to create trace_contextid_size in sysfs\n");
 
+       ret = sysfs_create_file(&dev->dev.kobj,
+                               &trace_branch_output_attr.attr);
+       if (ret)
+               dev_dbg(&dev->dev,
+                       "Failed to create trace_branch_output in sysfs\n");
+
        if (etmccer & ETMCCER_TIMESTAMPING_IMPLEMENTED) {
                ret = sysfs_create_file(&dev->dev.kobj,
                                        &trace_timestamp_attr.attr);