Messages in this thread | | | Date | Tue, 10 Jan 2023 09:30:56 +0000 | Subject | Re: [PATCH] coresight: tmc-etr: Don't enable ETR when it's not ready | From | James Clark <> |
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On 09/01/2023 23:43, Yabin Cui wrote: > Otherwise, it may cause error in AXI bus and result in a kernel panic.
Hi Yabin,
Thanks for the fix. Do you have a reproducer for this or some more info? For example is it a regression or has it always been there? And on which platform.
Thanks James
> > Signed-off-by: Yabin Cui <yabinc@google.com> > --- > .../hwtracing/coresight/coresight-tmc-core.c | 4 +++- > .../hwtracing/coresight/coresight-tmc-etr.c | 18 +++++++++++++++--- > drivers/hwtracing/coresight/coresight-tmc.h | 2 +- > 3 files changed, 19 insertions(+), 5 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-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c > index 867ad8bb9b0c..2da99dd41ed6 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, "not ready ETR isn't enabled\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; > 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);
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