On Wed, Jul 24, 2019 at 12:43:12PM +0100, Suzuki K Poulose wrote:
CoreSight TMC-ETR must have the non-secure invasive debug access enabled for use by self-hosted tracing. Without it, there is no point in enabling the ETR. So, let us check it in the TMC_AUTHSTATUS register and fail the probe if it is disabled.
Cc: Mathieu Poirier mathieu.poirier@linaro.org Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com
drivers/hwtracing/coresight/coresight-tmc.c | 12 ++++++++++++ drivers/hwtracing/coresight/coresight-tmc.h | 3 +++ 2 files changed, 15 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c index be37aff573b4..3055bf8e2236 100644 --- a/drivers/hwtracing/coresight/coresight-tmc.c +++ b/drivers/hwtracing/coresight/coresight-tmc.c @@ -236,6 +236,7 @@ coresight_tmc_reg(ffcr, TMC_FFCR); coresight_tmc_reg(mode, TMC_MODE); coresight_tmc_reg(pscr, TMC_PSCR); coresight_tmc_reg(axictl, TMC_AXICTL); +coresight_tmc_reg(authstatus, TMC_AUTHSTATUS); coresight_tmc_reg(devid, CORESIGHT_DEVID); coresight_tmc_reg64(rrp, TMC_RRP, TMC_RRPHI); coresight_tmc_reg64(rwp, TMC_RWP, TMC_RWPHI); @@ -255,6 +256,7 @@ static struct attribute *coresight_tmc_mgmt_attrs[] = { &dev_attr_devid.attr, &dev_attr_dba.attr, &dev_attr_axictl.attr,
- &dev_attr_authstatus.attr, NULL,
}; @@ -342,6 +344,13 @@ static inline bool tmc_etr_can_use_sg(struct device *dev) return fwnode_property_present(dev->fwnode, "arm,scatter-gather"); } +static inline bool tmc_etr_has_non_secure_access(struct tmc_drvdata *drvdata) +{
- u32 auth = readl_relaxed(drvdata->base + TMC_AUTHSTATUS);
- return (auth & TMC_AUTH_NSID_MASK) == 0x3;
+}
/* Detect and initialise the capabilities of a TMC ETR */ static int tmc_etr_setup_caps(struct device *parent, u32 devid, void *dev_caps) { @@ -349,6 +358,9 @@ static int tmc_etr_setup_caps(struct device *parent, u32 devid, void *dev_caps) u32 dma_mask = 0; struct tmc_drvdata *drvdata = dev_get_drvdata(parent);
- if (!tmc_etr_has_non_secure_access(drvdata))
return -EACCES;- /* Set the unadvertised capabilities */ tmc_etr_init_caps(drvdata, (u32)(unsigned long)dev_caps);
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h index 95d2e2747970..4c59f2a4ad0e 100644 --- a/drivers/hwtracing/coresight/coresight-tmc.h +++ b/drivers/hwtracing/coresight/coresight-tmc.h @@ -39,6 +39,7 @@ #define TMC_ITATBCTR2 0xef0 #define TMC_ITATBCTR1 0xef4 #define TMC_ITATBCTR0 0xef8 +#define TMC_AUTHSTATUS 0xfb8 /* register description */ /* TMC_CTL - 0x020 */ @@ -90,6 +91,8 @@ #define TMC_DEVID_AXIAW_SHIFT 17 #define TMC_DEVID_AXIAW_MASK 0x7f +#define TMC_AUTH_NSID_MASK GENMASK(1, 0)
enum tmc_config_type { TMC_CONFIG_TYPE_ETB, TMC_CONFIG_TYPE_ETR,
I have also picked-up patches 3-5.
Thanks, Mathieu
-- 2.21.0