--- /dev/null
+What: /sys/firmware/acpi/interrupts/
+Date: February 2008
+Contact: Len Brown <lenb@kernel.org>
+Description:
+ All ACPI interrupts are handled via a single IRQ,
+ the System Control Interrupt (SCI), which appears
+ as "acpi" in /proc/interrupts.
+
+ However, one of the main functions of ACPI is to make
+ the platform understand random hardware without
+ special driver support. So while the SCI handles a few
+ well known (fixed feature) interrupts sources, such
+ as the power button, it can also handle a variable
+ number of a "General Purpose Events" (GPE).
+
+ A GPE vectors to a specified handler in AML, which
+ can do a anything the BIOS writer wants from
+ OS context. GPE 0x12, for example, would vector
+ to a level or edge handler called _L12 or _E12.
+ The handler may do its business and return.
+ Or the handler may send send a Notify event
+ to a Linux device driver registered on an ACPI device,
+ such as a battery, or a processor.
+
+ To figure out where all the SCI's are coming from,
+ /sys/firmware/acpi/interrupts contains a file listing
+ every possible source, and the count of how many
+ times it has triggered.
+
+ $ cd /sys/firmware/acpi/interrupts
+ $ grep . *
+ error:0
+ ff_gbl_lock:0
+ ff_pmtimer:0
+ ff_pwr_btn:0
+ ff_rt_clk:0
+ ff_slp_btn:0
+ gpe00:0
+ gpe01:0
+ gpe02:0
+ gpe03:0
+ gpe04:0
+ gpe05:0
+ gpe06:0
+ gpe07:0
+ gpe08:0
+ gpe09:174
+ gpe0A:0
+ gpe0B:0
+ gpe0C:0
+ gpe0D:0
+ gpe0E:0
+ gpe0F:0
+ gpe10:0
+ gpe11:60
+ gpe12:0
+ gpe13:0
+ gpe14:0
+ gpe15:0
+ gpe16:0
+ gpe17:0
+ gpe18:0
+ gpe19:7
+ gpe1A:0
+ gpe1B:0
+ gpe1C:0
+ gpe1D:0
+ gpe1E:0
+ gpe1F:0
+ gpe_all:241
+ sci:241
+
+ sci - The total number of times the ACPI SCI
+ has claimed an interrupt.
+
+ gpe_all - count of SCI caused by GPEs.
+
+ gpeXX - count for individual GPE source
+
+ ff_gbl_lock - Global Lock
+
+ ff_pmtimer - PM Timer
+
+ ff_pwr_btn - Power Button
+
+ ff_rt_clk - Real Time Clock
+
+ ff_slp_btn - Sleep Button
+
+ error - an interrupt that can't be accounted for above.
+
+ Root has permission to clear any of these counters. Eg.
+ # echo 0 > gpe11
+
+ All counters can be cleared by clearing the total "sci":
+ # echo 0 > sci
+
+ None of these counters has an effect on the function
+ of the system, they are simply statistics.
#define ACPI_SYSTEM_CLASS "system"
#define ACPI_SYSTEM_DEVICE_NAME "System"
+u32 acpi_irq_handled;
+
/*
* Make ACPICA version work as module param
*/
return 0;
}
+/*
+ * Detailed ACPI IRQ counters in /sys/firmware/acpi/interrupts/
+ * See Documentation/ABI/testing/sysfs-firmware-acpi
+ */
+
+#define COUNT_GPE 0
+#define COUNT_SCI 1 /* acpi_irq_handled */
+#define COUNT_ERROR 2 /* other */
+#define NUM_COUNTERS_EXTRA 3
+
+static u32 *all_counters;
+static u32 num_gpes;
+static u32 num_counters;
+static struct attribute **all_attrs;
+static u32 acpi_gpe_count;
+
+static struct attribute_group interrupt_stats_attr_group = {
+ .name = "interrupts",
+};
+static struct kobj_attribute *counter_attrs;
+
+static int count_num_gpes(void)
+{
+ int count = 0;
+ struct acpi_gpe_xrupt_info *gpe_xrupt_info;
+ struct acpi_gpe_block_info *gpe_block;
+ acpi_cpu_flags flags;
+
+ flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
+
+ gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
+ while (gpe_xrupt_info) {
+ gpe_block = gpe_xrupt_info->gpe_block_list_head;
+ while (gpe_block) {
+ count += gpe_block->register_count *
+ ACPI_GPE_REGISTER_WIDTH;
+ gpe_block = gpe_block->next;
+ }
+ gpe_xrupt_info = gpe_xrupt_info->next;
+ }
+ acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
+
+ return count;
+}
+
+static void delete_gpe_attr_array(void)
+{
+ u32 *tmp = all_counters;
+
+ all_counters = NULL;
+ kfree(tmp);
+
+ if (counter_attrs) {
+ int i;
+
+ for (i = 0; i < num_gpes; i++)
+ kfree(counter_attrs[i].attr.name);
+
+ kfree(counter_attrs);
+ }
+ kfree(all_attrs);
+
+ return;
+}
+
+void acpi_os_gpe_count(u32 gpe_number)
+{
+ acpi_gpe_count++;
+
+ if (!all_counters)
+ return;
+
+ if (gpe_number < num_gpes)
+ all_counters[gpe_number]++;
+ else
+ all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_ERROR]++;
+
+ return;
+}
+
+void acpi_os_fixed_event_count(u32 event_number)
+{
+ if (!all_counters)
+ return;
+
+ if (event_number < ACPI_NUM_FIXED_EVENTS)
+ all_counters[num_gpes + event_number]++;
+ else
+ all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_ERROR]++;
+
+ return;
+}
+
+static ssize_t counter_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI] =
+ acpi_irq_handled;
+ all_counters[num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_GPE] =
+ acpi_gpe_count;
+
+ return sprintf(buf, "%d\n", all_counters[attr - counter_attrs]);
+}
+
+/*
+ * counter_set() sets the specified counter.
+ * setting the total "sci" file to any value clears all counters.
+ */
+static ssize_t counter_set(struct kobject *kobj,
+ struct kobj_attribute *attr, const char *buf, size_t size)
+{
+ int index = attr - counter_attrs;
+
+ if (index == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI) {
+ int i;
+ for (i = 0; i < num_counters; ++i)
+ all_counters[i] = 0;
+ acpi_gpe_count = 0;
+ acpi_irq_handled = 0;
+
+ } else
+ all_counters[index] = strtoul(buf, NULL, 0);
+
+ return size;
+}
+
+void acpi_irq_stats_init(void)
+{
+ int i;
+
+ if (all_counters)
+ return;
+
+ num_gpes = count_num_gpes();
+ num_counters = num_gpes + ACPI_NUM_FIXED_EVENTS + NUM_COUNTERS_EXTRA;
+
+ all_attrs = kzalloc(sizeof(struct attribute *) * (num_counters + 1),
+ GFP_KERNEL);
+ if (all_attrs == NULL)
+ return;
+
+ all_counters = kzalloc(sizeof(u32) * (num_counters), GFP_KERNEL);
+ if (all_counters == NULL)
+ goto fail;
+
+ counter_attrs = kzalloc(sizeof(struct kobj_attribute) * (num_counters),
+ GFP_KERNEL);
+ if (counter_attrs == NULL)
+ goto fail;
+
+ for (i = 0; i < num_counters; ++i) {
+ char buffer[10];
+ char *name;
+
+ if (i < num_gpes)
+ sprintf(buffer, "gpe%02X", i);
+ else if (i == num_gpes + ACPI_EVENT_PMTIMER)
+ sprintf(buffer, "ff_pmtimer");
+ else if (i == num_gpes + ACPI_EVENT_GLOBAL)
+ sprintf(buffer, "ff_gbl_lock");
+ else if (i == num_gpes + ACPI_EVENT_POWER_BUTTON)
+ sprintf(buffer, "ff_pwr_btn");
+ else if (i == num_gpes + ACPI_EVENT_SLEEP_BUTTON)
+ sprintf(buffer, "ff_slp_btn");
+ else if (i == num_gpes + ACPI_EVENT_RTC)
+ sprintf(buffer, "ff_rt_clk");
+ else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_GPE)
+ sprintf(buffer, "gpe_all");
+ else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_SCI)
+ sprintf(buffer, "sci");
+ else if (i == num_gpes + ACPI_NUM_FIXED_EVENTS + COUNT_ERROR)
+ sprintf(buffer, "error");
+ else
+ sprintf(buffer, "bug%02X", i);
+
+ name = kzalloc(strlen(buffer) + 1, GFP_KERNEL);
+ if (name == NULL)
+ goto fail;
+ strncpy(name, buffer, strlen(buffer) + 1);
+
+ counter_attrs[i].attr.name = name;
+ counter_attrs[i].attr.mode = 0644;
+ counter_attrs[i].show = counter_show;
+ counter_attrs[i].store = counter_set;
+
+ all_attrs[i] = &counter_attrs[i].attr;
+ }
+
+ interrupt_stats_attr_group.attrs = all_attrs;
+ sysfs_create_group(acpi_kobj, &interrupt_stats_attr_group);
+ return;
+
+fail:
+ delete_gpe_attr_array();
+ return;
+}
+
+static void __exit interrupt_stats_exit(void)
+{
+ sysfs_remove_group(acpi_kobj, &interrupt_stats_attr_group);
+
+ delete_gpe_attr_array();
+
+ return;
+}
+
/* --------------------------------------------------------------------------
FS Interface (/proc)
-------------------------------------------------------------------------- */
projects / linux-2.6-omap-h63xx.git / commitdiff