Commit 8a4bc4f1 authored by Suzuki K Poulose's avatar Suzuki K Poulose Committed by Greg Kroah-Hartman
Browse files

coresight: tmc-etr: Check if non-secure access is enabled 



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: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20190829202842.580-7-mathieu.poirier@linaro.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent f52ff9b7

drivers/hwtracing/coresight/coresight-tmc.c

+12 −0
Original line number Diff line number Diff line
@@ -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);

drivers/hwtracing/coresight/coresight-tmc.h

+3 −0
Original line number Diff line number Diff line
@@ -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,

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