[PATCH v3] coresight: tmc: Don't enable TMC when it's not ready.
Yabin Cui
yabinc at google.com
Thu Feb 2 13:46:32 PST 2023
If TMC ETR is enabled without being ready, in later use we may
see AXI bus errors caused by accessing invalid addresses.
Signed-off-by: Yabin Cui <yabinc at google.com>
---
V1 -> V2: Make change to all TMCs instead of just ETR
V2 -> V3: Handle etr enable failure in tmc_read_unprepare_etr
.../hwtracing/coresight/coresight-tmc-core.c | 4 +-
.../hwtracing/coresight/coresight-tmc-etf.c | 43 +++++++++++++++----
.../hwtracing/coresight/coresight-tmc-etr.c | 25 +++++++++--
drivers/hwtracing/coresight/coresight-tmc.h | 2 +-
4 files changed, 59 insertions(+), 15 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
index 07abf28ad725..c106d142e632 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-core.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
@@ -31,7 +31,7 @@ DEFINE_CORESIGHT_DEVLIST(etb_devs, "tmc_etb");
DEFINE_CORESIGHT_DEVLIST(etf_devs, "tmc_etf");
DEFINE_CORESIGHT_DEVLIST(etr_devs, "tmc_etr");
-void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata)
+int tmc_wait_for_tmcready(struct tmc_drvdata *drvdata)
{
struct coresight_device *csdev = drvdata->csdev;
struct csdev_access *csa = &csdev->access;
@@ -40,7 +40,9 @@ void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata)
if (coresight_timeout(csa, TMC_STS, TMC_STS_TMCREADY_BIT, 1)) {
dev_err(&csdev->dev,
"timeout while waiting for TMC to be Ready\n");
+ return -EBUSY;
}
+ return 0;
}
void tmc_flush_and_stop(struct tmc_drvdata *drvdata)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 4c4cbd1f7258..2840227e9135 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -16,12 +16,19 @@
static int tmc_set_etf_buffer(struct coresight_device *csdev,
struct perf_output_handle *handle);
-static void __tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
+static int __tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
{
+ int rc = 0;
+
CS_UNLOCK(drvdata->base);
/* Wait for TMCSReady bit to be set */
- tmc_wait_for_tmcready(drvdata);
+ rc = tmc_wait_for_tmcready(drvdata);
+ if (rc) {
+ dev_err(&drvdata->csdev->dev, "fails to enable not ready TMC\n");
+ CS_LOCK(drvdata->base);
+ return rc;
+ }
writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE);
writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI |
@@ -33,6 +40,7 @@ static void __tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
tmc_enable_hw(drvdata);
CS_LOCK(drvdata->base);
+ return rc;
}
static int tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
@@ -42,8 +50,10 @@ static int tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
if (rc)
return rc;
- __tmc_etb_enable_hw(drvdata);
- return 0;
+ rc = __tmc_etb_enable_hw(drvdata);
+ if (rc)
+ coresight_disclaim_device(drvdata->csdev);
+ return rc;
}
static void tmc_etb_dump_hw(struct tmc_drvdata *drvdata)
@@ -91,12 +101,19 @@ static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
coresight_disclaim_device(drvdata->csdev);
}
-static void __tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
+static int __tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
{
+ int rc = 0;
+
CS_UNLOCK(drvdata->base);
/* Wait for TMCSReady bit to be set */
- tmc_wait_for_tmcready(drvdata);
+ rc = tmc_wait_for_tmcready(drvdata);
+ if (rc) {
+ dev_err(&drvdata->csdev->dev, "fails to enable not ready TMC\n");
+ CS_LOCK(drvdata->base);
+ return rc;
+ }
writel_relaxed(TMC_MODE_HARDWARE_FIFO, drvdata->base + TMC_MODE);
writel_relaxed(TMC_FFCR_EN_FMT | TMC_FFCR_EN_TI,
@@ -105,6 +122,7 @@ static void __tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
tmc_enable_hw(drvdata);
CS_LOCK(drvdata->base);
+ return rc;
}
static int tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
@@ -114,8 +132,10 @@ static int tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
if (rc)
return rc;
- __tmc_etf_enable_hw(drvdata);
- return 0;
+ rc = __tmc_etf_enable_hw(drvdata);
+ if (rc)
+ coresight_disclaim_device(drvdata->csdev);
+ return rc;
}
static void tmc_etf_disable_hw(struct tmc_drvdata *drvdata)
@@ -639,6 +659,7 @@ int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata)
char *buf = NULL;
enum tmc_mode mode;
unsigned long flags;
+ int rc = 0;
/* config types are set a boot time and never change */
if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETB &&
@@ -664,7 +685,11 @@ int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata)
* can't be NULL.
*/
memset(drvdata->buf, 0, drvdata->size);
- __tmc_etb_enable_hw(drvdata);
+ rc = __tmc_etb_enable_hw(drvdata);
+ if (rc) {
+ spin_unlock_irqrestore(&drvdata->spinlock, flags);
+ return rc;
+ }
} else {
/*
* The ETB/ETF is not tracing and the buffer was just read.
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 867ad8bb9b0c..4952425dd6e4 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -983,15 +983,21 @@ static void tmc_sync_etr_buf(struct tmc_drvdata *drvdata)
etr_buf->ops->sync(etr_buf, rrp, rwp);
}
-static void __tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
+static int __tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
{
u32 axictl, sts;
struct etr_buf *etr_buf = drvdata->etr_buf;
+ int rc = 0;
CS_UNLOCK(drvdata->base);
/* Wait for TMCSReady bit to be set */
- tmc_wait_for_tmcready(drvdata);
+ rc = tmc_wait_for_tmcready(drvdata);
+ if (rc) {
+ dev_err(&drvdata->csdev->dev, "fails to enable not ready TMC\n");
+ CS_LOCK(drvdata->base);
+ return rc;
+ }
writel_relaxed(etr_buf->size / 4, drvdata->base + TMC_RSZ);
writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE);
@@ -1032,6 +1038,7 @@ static void __tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
tmc_enable_hw(drvdata);
CS_LOCK(drvdata->base);
+ return rc;
}
static int tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
@@ -1060,7 +1067,12 @@ static int tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
rc = coresight_claim_device(drvdata->csdev);
if (!rc) {
drvdata->etr_buf = etr_buf;
- __tmc_etr_enable_hw(drvdata);
+ rc = __tmc_etr_enable_hw(drvdata);
+ if (rc) {
+ drvdata->etr_buf = NULL;
+ coresight_disclaim_device(drvdata->csdev);
+ tmc_etr_disable_catu(drvdata);
+ }
}
return rc;
@@ -1750,6 +1762,7 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
{
unsigned long flags;
struct etr_buf *sysfs_buf = NULL;
+ int rc = 0;
/* config types are set a boot time and never change */
if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
@@ -1764,7 +1777,11 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
* buffer. Since the tracer is still enabled drvdata::buf can't
* be NULL.
*/
- __tmc_etr_enable_hw(drvdata);
+ rc = __tmc_etr_enable_hw(drvdata);
+ if (rc) {
+ spin_unlock_irqrestore(&drvdata->spinlock, flags);
+ return rc;
+ }
} else {
/*
* The ETR is not tracing and the buffer was just read.
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 66959557cf39..01c0382a29c0 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -255,7 +255,7 @@ struct tmc_sg_table {
};
/* Generic functions */
-void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata);
+int tmc_wait_for_tmcready(struct tmc_drvdata *drvdata);
void tmc_flush_and_stop(struct tmc_drvdata *drvdata);
void tmc_enable_hw(struct tmc_drvdata *drvdata);
void tmc_disable_hw(struct tmc_drvdata *drvdata);
--
2.39.1.519.gcb327c4b5f-goog
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