On 2/13/24 16:02, Suzuki K Poulose wrote: > On 13/02/2024 03:13, Anshuman Khandual wrote: >> >> >> On 2/12/24 17:43, Suzuki K Poulose wrote: >>> On 23/01/2024 05:46, Anshuman Khandual wrote: >>>> This extracts device properties from AMBA pid based table lookup. This also >>>> defers tmc_etr_setup_caps() after the coresight device has been initialized >>>> so that PID value can be read. >>>> >>>> Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx> >>>> Cc: Mike Leach <mike.leach@xxxxxxxxxx> >>>> Cc: James Clark <james.clark@xxxxxxx> >>>> Cc: coresight@xxxxxxxxxxxxxxxx >>>> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx >>>> Cc: linux-kernel@xxxxxxxxxxxxxxx >>>> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> >>>> --- >>>> .../hwtracing/coresight/coresight-tmc-core.c | 19 +++++++++++++------ >>>> 1 file changed, 13 insertions(+), 6 deletions(-) >>>> >>>> diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c >>>> index 7ec5365e2b64..e71db3099a29 100644 >>>> --- a/drivers/hwtracing/coresight/coresight-tmc-core.c >>>> +++ b/drivers/hwtracing/coresight/coresight-tmc-core.c >>>> @@ -370,16 +370,24 @@ static inline bool tmc_etr_has_non_secure_access(struct tmc_drvdata *drvdata) >>>> return (auth & TMC_AUTH_NSID_MASK) == 0x3; >>>> } >>>> +#define TMC_AMBA_MASK 0xfffff >>>> + >>>> +static const struct amba_id tmc_ids[]; >>>> + >>>> /* Detect and initialise the capabilities of a TMC ETR */ >>>> -static int tmc_etr_setup_caps(struct device *parent, u32 devid, void *dev_caps) >>>> +static int tmc_etr_setup_caps(struct device *parent, u32 devid) >>>> { >>>> int rc; >>>> - u32 dma_mask = 0; >>>> + u32 tmc_pid, dma_mask = 0; >>>> struct tmc_drvdata *drvdata = dev_get_drvdata(parent); >>>> + void *dev_caps; >>>> if (!tmc_etr_has_non_secure_access(drvdata)) >>>> return -EACCES; >>>> + tmc_pid = coresight_get_pid(&drvdata->csdev->access) & TMC_AMBA_MASK; >>>> + dev_caps = coresight_get_uci_data_from_amba(tmc_ids, tmc_pid); >>>> + >>>> /* Set the unadvertised capabilities */ >>>> tmc_etr_init_caps(drvdata, (u32)(unsigned long)dev_caps); >>>> @@ -497,10 +505,6 @@ static int tmc_probe(struct amba_device *adev, const struct amba_id *id) >>>> desc.type = CORESIGHT_DEV_TYPE_SINK; >>>> desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_SYSMEM; >>>> desc.ops = &tmc_etr_cs_ops; >>>> - ret = tmc_etr_setup_caps(dev, devid, >>>> - coresight_get_uci_data(id)); >>>> - if (ret) >>>> - goto out; >>>> idr_init(&drvdata->idr); >>>> mutex_init(&drvdata->idr_mutex); >>>> dev_list = &etr_devs; >>>> @@ -539,6 +543,9 @@ static int tmc_probe(struct amba_device *adev, const struct amba_id *id) >>>> goto out; >>>> } >>>> + if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) >>>> + ret = tmc_etr_setup_caps(dev, devid); >>>> + >>> >>> With this change, we silently accept an ETR that may only have "SECURE" access only and crash later while we try to enable tracing. You could >>> pass in the "access" (which is already in 'desc.access' in the original >>> call site and deal with it ? >> >> Just wondering, if something like the following will help ? A failed tmc_etr_setup_caps() >> because of failed tmc_etr_has_non_secure_access(), will unregister the coresight device >> before returning. >> >> --- a/drivers/hwtracing/coresight/coresight-tmc-core.c >> +++ b/drivers/hwtracing/coresight/coresight-tmc-core.c >> @@ -538,8 +538,13 @@ static int __tmc_probe(struct device *dev, struct resource *res) >> goto out; >> } >> - if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) >> + if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) { >> ret = tmc_etr_setup_caps(dev, devid); >> + if (ret) { >> + coresight_unregister(drvdata->csdev); >> + goto out; >> + } >> + } > > Why do we move the tmc_etr_setup_caps() in the first place ? We could retain where that was and pass "desc.access" parameter rather than registering the csdev and then relying csdev->access ? Agreed, and after implementing the changes suggested above, the entire patch will look something like the following. Please do confirm if this looks good enough. --- a/drivers/hwtracing/coresight/coresight-tmc-core.c +++ b/drivers/hwtracing/coresight/coresight-tmc-core.c @@ -370,16 +370,25 @@ static inline bool tmc_etr_has_non_secure_access(struct tmc_drvdata *drvdata) return (auth & TMC_AUTH_NSID_MASK) == 0x3; } +#define TMC_AMBA_MASK 0xfffff + +static const struct amba_id tmc_ids[]; + /* Detect and initialise the capabilities of a TMC ETR */ -static int tmc_etr_setup_caps(struct device *parent, u32 devid, void *dev_caps) +static int tmc_etr_setup_caps(struct device *parent, u32 devid, + struct csdev_access *access) { int rc; - u32 dma_mask = 0; + u32 tmc_pid, dma_mask = 0; struct tmc_drvdata *drvdata = dev_get_drvdata(parent); + void *dev_caps; if (!tmc_etr_has_non_secure_access(drvdata)) return -EACCES; + tmc_pid = coresight_get_pid(access) & TMC_AMBA_MASK; + dev_caps = coresight_get_uci_data_from_amba(tmc_ids, tmc_pid); + /* Set the unadvertised capabilities */ tmc_etr_init_caps(drvdata, (u32)(unsigned long)dev_caps); @@ -497,8 +506,7 @@ static int tmc_probe(struct amba_device *adev, const struct amba_id *id) desc.type = CORESIGHT_DEV_TYPE_SINK; desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_SYSMEM; desc.ops = &tmc_etr_cs_ops; - ret = tmc_etr_setup_caps(dev, devid, - coresight_get_uci_data(id)); + ret = tmc_etr_setup_caps(dev, devid, &desc.access); if (ret) goto out; idr_init(&drvdata->idr);