From a1c45d3ebd30cf8b9b1131c1335d603f3c46999c Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Mon, 12 Jun 2023 18:16:33 +0100 Subject: [PATCH] perf/arm-cmn: Add sysfs identifier Expose a sysfs identifier encapsulating the CMN part number and revision so that jevents can narrow down a fundamental set of possible events for calculating metrics. Configuration-dependent aspects - such as whether a given node type is present, and/or a given node ID is valid - are still not covered, and in general it's hard to see how userspace could handle them, so we won't be removing any data or validation logic from the driver any time soon, but at least it's a step in a useful direction. Signed-off-by: Robin Murphy Reviewed-and-tested-by: Ilkka Koskinen Tested-by: Jing Zhang Link: https://lore.kernel.org/r/b8a14c14fcdf028939ebf57849863e8ae01743de.1686588640.git.robin.murphy@arm.com Signed-off-by: Will Deacon --- drivers/perf/arm-cmn.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c index 4a1dc4b527f6..b8c15878bc86 100644 --- a/drivers/perf/arm-cmn.c +++ b/drivers/perf/arm-cmn.c @@ -1199,19 +1199,31 @@ static ssize_t arm_cmn_cpumask_show(struct device *dev, static struct device_attribute arm_cmn_cpumask_attr = __ATTR(cpumask, 0444, arm_cmn_cpumask_show, NULL); -static struct attribute *arm_cmn_cpumask_attrs[] = { +static ssize_t arm_cmn_identifier_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct arm_cmn *cmn = to_cmn(dev_get_drvdata(dev)); + + return sysfs_emit(buf, "%03x%02x\n", cmn->part, cmn->rev); +} + +static struct device_attribute arm_cmn_identifier_attr = + __ATTR(identifier, 0444, arm_cmn_identifier_show, NULL); + +static struct attribute *arm_cmn_other_attrs[] = { &arm_cmn_cpumask_attr.attr, + &arm_cmn_identifier_attr.attr, NULL, }; -static const struct attribute_group arm_cmn_cpumask_attr_group = { - .attrs = arm_cmn_cpumask_attrs, +static const struct attribute_group arm_cmn_other_attrs_group = { + .attrs = arm_cmn_other_attrs, }; static const struct attribute_group *arm_cmn_attr_groups[] = { &arm_cmn_event_attrs_group, &arm_cmn_format_attrs_group, - &arm_cmn_cpumask_attr_group, + &arm_cmn_other_attrs_group, NULL };