ACPI: create /sys/firmware/acpi/interrupts

See Documentation/ABI/testing/sysfs-firmware-acpi

Based-on-original-patch-by: Luming Yu <luming.yu@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/acpi/system.c b/drivers/acpi/system.c
index 5ffe0ea..ce88171 100644
--- a/drivers/acpi/system.c
+++ b/drivers/acpi/system.c
@@ -40,6 +40,8 @@
 #define ACPI_SYSTEM_CLASS		"system"
 #define ACPI_SYSTEM_DEVICE_NAME		"System"
 
+u32 acpi_irq_handled;
+
 /*
  * Make ACPICA version work as module param
  */
@@ -166,6 +168,212 @@
 	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)
    -------------------------------------------------------------------------- */