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Commit 2703d74c authored by Mathieu Poirier's avatar Mathieu Poirier Committed by Greg Kroah-Hartman
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coresight: etm4x: adding configurable address range filtering 



This patch adds the capability to specify address ranges from
the perf cmd line using the --filter option.  If the IP
falls within the range(s) program flow traces are generated.

Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent f0d30cc3

drivers/hwtracing/coresight/coresight-etm4x.c

+119 −9
Original line number Diff line number Diff line
@@ -45,7 +45,9 @@ module_param_named(boot_enable, boot_enable, int, S_IRUGO); 
/* The number of ETMv4 currently registered */

static int etm4_count;

static struct etmv4_drvdata *etmdrvdata[NR_CPUS];

static void etm4_set_default(struct etmv4_config *config);

static void etm4_set_default_config(struct etmv4_config *config);

static int etm4_set_event_filters(struct etmv4_drvdata *drvdata,

				  struct perf_event *event);



static enum cpuhp_state hp_online;
@@ -187,11 +189,14 @@ static void etm4_enable_hw(void *info) 
static int etm4_parse_event_config(struct etmv4_drvdata *drvdata,

				   struct perf_event *event)

{

	int ret = 0;

	struct etmv4_config *config = &drvdata->config;

	struct perf_event_attr *attr = &event->attr;



	if (!attr)

		return -EINVAL;

	if (!attr) {

		ret = -EINVAL;

		goto out;

	}



	/* Clear configuration from previous run */

	memset(config, 0, sizeof(struct etmv4_config));
@@ -203,7 +208,12 @@ static int etm4_parse_event_config(struct etmv4_drvdata *drvdata, 
		config->mode = ETM_MODE_EXCL_USER;



	/* Always start from the default config */

	etm4_set_default(config);

	etm4_set_default_config(config);



	/* Configure filters specified on the perf cmd line, if any. */

	ret = etm4_set_event_filters(drvdata, event);

	if (ret)

		goto out;



	/* Go from generic option to ETMv4 specifics */

	if (attr->config & BIT(ETM_OPT_CYCACC))
@@ -211,23 +221,30 @@ static int etm4_parse_event_config(struct etmv4_drvdata *drvdata, 
	if (attr->config & BIT(ETM_OPT_TS))

		config->cfg |= ETMv4_MODE_TIMESTAMP;



	return 0;

out:

	return ret;

}



static int etm4_enable_perf(struct coresight_device *csdev,

			    struct perf_event *event)

{

	int ret = 0;

	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);



	if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id()))

		return -EINVAL;

	if (WARN_ON_ONCE(drvdata->cpu != smp_processor_id())) {

		ret = -EINVAL;

		goto out;

	}



	/* Configure the tracer based on the session's specifics */

	etm4_parse_event_config(drvdata, event);

	ret = etm4_parse_event_config(drvdata, event);

	if (ret)

		goto out;

	/* And enable it */

	etm4_enable_hw(drvdata);



	return 0;

out:

	return ret;

}



static int etm4_enable_sysfs(struct coresight_device *csdev)
@@ -682,6 +699,99 @@ static void etm4_set_default(struct etmv4_config *config) 
	etm4_set_default_filter(config);

}



static int etm4_get_next_comparator(struct etmv4_drvdata *drvdata, u32 type)

{

	int nr_comparator, index = 0;

	struct etmv4_config *config = &drvdata->config;



	/*

	 * nr_addr_cmp holds the number of comparator _pair_, so time 2

	 * for the total number of comparators.

	 */

	nr_comparator = drvdata->nr_addr_cmp * 2;



	/* Go through the tally of comparators looking for a free one. */

	while (index < nr_comparator) {

		switch (type) {

		case ETM_ADDR_TYPE_RANGE:

			if (config->addr_type[index] == ETM_ADDR_TYPE_NONE &&

			    config->addr_type[index + 1] == ETM_ADDR_TYPE_NONE)

				return index;



			/* Address range comparators go in pairs */

			index += 2;

			break;

		default:

			return -EINVAL;

		}

	}



	/* If we are here all the comparators have been used. */

	return -ENOSPC;

}



static int etm4_set_event_filters(struct etmv4_drvdata *drvdata,

				  struct perf_event *event)

{

	int i, comparator, ret = 0;

	struct etmv4_config *config = &drvdata->config;

	struct etm_filters *filters = event->hw.addr_filters;



	if (!filters)

		goto default_filter;



	/* Sync events with what Perf got */

	perf_event_addr_filters_sync(event);



	/*

	 * If there are no filters to deal with simply go ahead with

	 * the default filter, i.e the entire address range.

	 */

	if (!filters->nr_filters)

		goto default_filter;



	for (i = 0; i < filters->nr_filters; i++) {

		struct etm_filter *filter = &filters->etm_filter[i];

		enum etm_addr_type type = filter->type;



		/* See if a comparator is free. */

		comparator = etm4_get_next_comparator(drvdata, type);

		if (comparator < 0) {

			ret = comparator;

			goto out;

		}



		switch (type) {

		case ETM_ADDR_TYPE_RANGE:

			etm4_set_comparator_filter(config,

						   filter->start_addr,

						   filter->stop_addr,

						   comparator);

			/*

			 * TRCVICTLR::SSSTATUS == 1, the start-stop logic is

			 * in the started state

			 */

			config->vinst_ctrl |= BIT(9);



			/* No start-stop filtering for ViewInst */

			config->vissctlr = 0x0;

			break;

		default:

			ret = -EINVAL;

			goto out;

		}

	}



	goto out;





default_filter:

	etm4_set_default_filter(config);



out:

	return ret;

}



void etm4_config_trace_mode(struct etmv4_config *config)

{

	u32 addr_acc, mode;