Commit b4d9ef47 authored by Leo Yan's avatar Leo Yan Committed by Suzuki K Poulose
Browse files

coresight: cti: Access ASICCTL only when implemented 



According to the Arm ARM (DDI 0487 L.b), ASICCTL is implemented only
when CTIDEVID.EXTMUXNUM is non-zero.

Based on CTIDEVID.EXTMUXNUM, add a flag 'asicctl_impl' to indicate
whether the register is implemented, and access ASICCTL conditionally
based on the flag.

Allow the sysfs node to be visible only when the register is
implemented.

Reviewed-by: default avatarMike Leach <mike.leach@arm.com>
Signed-off-by: default avatarLeo Yan <leo.yan@arm.com>
Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20260226-arm_coresight_cti_refactor_v1-v2-3-b30fada3cfec@arm.com
parent 6582fe69

drivers/hwtracing/coresight/coresight-cti-core.c

+4 −1
Original line number Diff line number Diff line
@@ -68,6 +68,7 @@ void cti_write_all_hw_regs(struct cti_drvdata *drvdata) 


	/* other regs */

	writel_relaxed(config->ctigate, drvdata->base + CTIGATE);

	if (config->asicctl_impl)

		writel_relaxed(config->asicctl, drvdata->base + ASICCTL);

	writel_relaxed(config->ctiappset, drvdata->base + CTIAPPSET);
@@ -221,6 +222,8 @@ static void cti_set_default_config(struct device *dev, 
	config->trig_filter_enable = true;

	config->ctigate = GENMASK(config->nr_ctm_channels - 1, 0);

	config->enable_req_count = 0;



	config->asicctl_impl = !!FIELD_GET(GENMASK(4, 0), devid);

}



/*

drivers/hwtracing/coresight/coresight-cti-sysfs.c

+13 −0
Original line number Diff line number Diff line
@@ -537,6 +537,18 @@ static struct attribute *coresight_cti_regs_attrs[] = { 
	NULL,

};



static umode_t coresight_cti_regs_is_visible(struct kobject *kobj,

					     struct attribute *attr, int idx)

{

	struct device *dev = kobj_to_dev(kobj);

	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);



	if (attr == &dev_attr_asicctl.attr && !drvdata->config.asicctl_impl)

		return 0;



	return attr->mode;

}



/* CTI channel x-trigger programming */

static int

cti_trig_op_parse(struct device *dev, enum cti_chan_op op,
@@ -1174,6 +1186,7 @@ static const struct attribute_group coresight_cti_mgmt_group = { 


static const struct attribute_group coresight_cti_regs_group = {

	.attrs = coresight_cti_regs_attrs,

	.is_visible = coresight_cti_regs_is_visible,

	.name = "regs",

};

drivers/hwtracing/coresight/coresight-cti.h

+2 −0
Original line number Diff line number Diff line
@@ -119,6 +119,7 @@ struct cti_device { 
 * @nr_trig_max: Max number of trigger signals implemented on device.

 *		 (max of trig_in or trig_out) - from ID register.

 * @nr_ctm_channels: number of available CTM channels - from ID register.

 * @asicctl_impl: true if asicctl is implemented.

 * @enable_req_count: CTI is enabled alongside >=1 associated devices.

 * @hw_enabled: true if hw is currently enabled.

 * @hw_powered: true if associated cpu powered on, or no cpu.
@@ -140,6 +141,7 @@ struct cti_config { 
	/* hardware description */

	int nr_ctm_channels;

	int nr_trig_max;

	bool asicctl_impl;



	/* cti enable control */

	int enable_req_count;