[PATCH 11/15] ARM: etm: Check arch version and disable data tracing for ptm

John Stultz
2012-06-20T22:48:21Z

From: Arve Hjønnevåg <arve@android.com>

Check arch version and disable data tracing for ptm

CC: Russell King <linux@arm.linux.org.uk>
CC: Paul Gortmaker <paul.gortmaker@windriver.com>
CC: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
---
arch/arm/include/asm/hardware/coresight.h | 5 +++++
arch/arm/kernel/etm.c | 23 ++++++++++++++++++-----
2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/arch/arm/include/asm/hardware/coresight.h b/arch/arm/include/asm/hardware/coresight.h
index 6643d6c..0fad8f8 100644
--- a/arch/arm/include/asm/hardware/coresight.h
+++ b/arch/arm/include/asm/hardware/coresight.h
@@ -60,6 +60,7 @@

/* ETM configuration code register */
#define ETMR_CONFCODE (0x04)
+#define ETMCCR_ETMIDR_PRESENT BIT(31)

/* ETM trace start/stop resource control register */
#define ETMR_TRACESSCTRL (0x18)
@@ -126,6 +127,10 @@
ETMCTRL_BRANCH_OUTPUT | \
ETMCTRL_DO_CONTEXTID)

+#define ETMR_ID 0x1e4
+#define ETMIDR_VERSION(x) (((x) >> 4) & 0xff)
+#define ETMIDR_VERSION_PFT_1_0 0x30
+
#define ETMR_TRACEIDR 0x200

/* ETM management registers, "ETM Architecture", 3.5.24 */
diff --git a/arch/arm/kernel/etm.c b/arch/arm/kernel/etm.c
index bad28de..e42b706 100644
--- a/arch/arm/kernel/etm.c
+++ b/arch/arm/kernel/etm.c
@@ -724,6 +724,9 @@ static int __devinit etm_probe(struct amba_device *dev, const struct amba_id *id
int ret = 0;
void __iomem **new_regs;
int new_count;
+ u32 etmccr;
+ u32 etmidr;
+ u8 etm_version = 0;

mutex_lock(&t->mutex);
new_count = t->etm_regs_count + 1;
@@ -758,7 +761,12 @@ static int __devinit etm_probe(struct amba_device *dev, const struct amba_id *id
/* dummy first read */
(void)etm_readl(&tracer, t->etm_regs_count, ETMMR_OSSRR);

- t->ncmppairs = etm_readl(t, t->etm_regs_count, ETMR_CONFCODE) & 0xf;
+ etmccr = etm_readl(t, t->etm_regs_count, ETMR_CONFCODE);
+ t->ncmppairs = etmccr & 0xf;
+ if (etmccr & ETMCCR_ETMIDR_PRESENT) {
+ etmidr = etm_readl(t, t->etm_regs_count, ETMR_ID);
+ etm_version = ETMIDR_VERSION(etmidr);
+ }
etm_writel(t, t->etm_regs_count, 0x441, ETMR_CTRL);
etm_writel(t, t->etm_regs_count, new_count, ETMR_TRACEIDR);
etm_lock(t, t->etm_regs_count);
@@ -781,10 +789,15 @@ static int __devinit etm_probe(struct amba_device *dev, const 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");
+ if (etm_version < ETMIDR_VERSION_PFT_1_0) {
+ 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");
+ } else {
+ tracer.flags &= ~TRACER_TRACE_DATA;
+ }

dev_dbg(&dev->dev, "ETM AMBA driver initialized.\n");

--
1.7.9.5