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>

9 files changed, 325 insertions, 9 deletions

diff --git a/Documentation/ABI/testing/sysfs-firmware-acpi b/Documentation/ABI/testing/sysfs-firmware-acpi
new file mode 100644
index 000000000000..9470ed9afcc0
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-firmware-acpi
@@ -0,0 +1,99 @@
+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.
diff --git a/drivers/acpi/events/evevent.c b/drivers/acpi/events/evevent.c
index e41287815ea1..3048801a37b5 100644
--- a/drivers/acpi/events/evevent.c
+++ b/drivers/acpi/events/evevent.c
@@ -259,7 +259,7 @@ u32 acpi_ev_fixed_event_detect(void)
                         enable_bit_mask)) {
 
                         /* Found an active (signalled) event */
-
+                        acpi_os_fixed_event_count(i);
                         int_status |= acpi_ev_fixed_event_dispatch((u32) i);
                 }
         }
diff --git a/drivers/acpi/events/evgpe.c b/drivers/acpi/events/evgpe.c
index e22f4a973c0f..4bd9e2291bd9 100644
--- a/drivers/acpi/events/evgpe.c
+++ b/drivers/acpi/events/evgpe.c
@@ -618,7 +618,7 @@ acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 
         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
 
-        acpi_gpe_count++;
+        acpi_os_gpe_count(gpe_number);
 
         /*
          * If edge-triggered, clear the GPE status bit now.  Note that
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index e53fb516f9d4..1087efeca9b1 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -332,7 +332,15 @@ acpi_os_table_override(struct acpi_table_header * existing_table,
 
 static irqreturn_t acpi_irq(int irq, void *dev_id)
 {
-        return (*acpi_irq_handler) (acpi_irq_context) ? IRQ_HANDLED : IRQ_NONE;
+        u32 handled;
+
+        handled = (*acpi_irq_handler) (acpi_irq_context);
+
+        if (handled) {
+                acpi_irq_handled++;
+                return IRQ_HANDLED;
+        } else
+                return IRQ_NONE;
 }
 
 acpi_status
@@ -341,6 +349,8 @@ acpi_os_install_interrupt_handler(u32 gsi, acpi_osd_handler handler,
 {
         unsigned int irq;
 
+        acpi_irq_stats_init();
+
         /*
          * Ignore the GSI from the core, and use the value in our copy of the
          * FADT. It may not be the same if an interrupt source override exists
diff --git a/drivers/acpi/system.c b/drivers/acpi/system.c
index 5ffe0ea18967..ce881713f7a6 100644
--- a/drivers/acpi/system.c
+++ b/drivers/acpi/system.c
@@ -40,6 +40,8 @@ ACPI_MODULE_NAME("system");
 #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 @@ static int acpi_system_sysfs_init(void)
         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)
    -------------------------------------------------------------------------- */
diff --git a/drivers/acpi/utilities/utglobal.c b/drivers/acpi/utilities/utglobal.c
index 93ea8290b4f7..630c9a2c5b7b 100644
--- a/drivers/acpi/utilities/utglobal.c
+++ b/drivers/acpi/utilities/utglobal.c
@@ -671,7 +671,6 @@ void acpi_ut_init_globals(void)
 
         /* GPE support */
 
-        acpi_gpe_count = 0;
         acpi_gbl_gpe_xrupt_list_head = NULL;
         acpi_gbl_gpe_fadt_blocks[0] = NULL;
         acpi_gbl_gpe_fadt_blocks[1] = NULL;
@@ -735,4 +734,3 @@ void acpi_ut_init_globals(void)
 
 ACPI_EXPORT_SYMBOL(acpi_dbg_level)
     ACPI_EXPORT_SYMBOL(acpi_dbg_layer)
-    ACPI_EXPORT_SYMBOL(acpi_gpe_count)
diff --git a/include/acpi/acglobal.h b/include/acpi/acglobal.h
index 347a911d8237..47a1fd8f2d8a 100644
--- a/include/acpi/acglobal.h
+++ b/include/acpi/acglobal.h
@@ -117,10 +117,6 @@ extern u32 acpi_dbg_layer;
 
 extern u32 acpi_gbl_nesting_level;
 
-/* Event counters */
-
-ACPI_EXTERN u32 acpi_gpe_count;
-
 /* Support for dynamic control method tracing mechanism */
 
 ACPI_EXTERN u32 acpi_gbl_original_dbg_level;
diff --git a/include/acpi/acpiosxf.h b/include/acpi/acpiosxf.h
index ca882b8e7d10..1a16cfbe9e0d 100644
--- a/include/acpi/acpiosxf.h
+++ b/include/acpi/acpiosxf.h
@@ -181,6 +181,9 @@ acpi_os_install_interrupt_handler(u32 gsi,
 acpi_status
 acpi_os_remove_interrupt_handler(u32 gsi, acpi_osd_handler service_routine);
 
+void acpi_os_gpe_count(u32 gpe_number);
+void acpi_os_fixed_event_count(u32 fixed_event_number);
+
 /*
  * Threads and Scheduling
  */
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 63f2e6ed698f..cb911f3e40f5 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -115,7 +115,9 @@ int acpi_unmap_lsapic(int cpu);
 
 int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base);
 int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base);
+void acpi_irq_stats_init(void);
 
+extern u32 acpi_irq_handled;
 extern int acpi_mp_config;
 
 extern struct acpi_mcfg_allocation *pci_mmcfg_config;