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path: root/drivers/acpi/acpi_pad.c
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Diffstat (limited to 'drivers/acpi/acpi_pad.c')
-rw-r--r--drivers/acpi/acpi_pad.c291
1 files changed, 127 insertions, 164 deletions
diff --git a/drivers/acpi/acpi_pad.c b/drivers/acpi/acpi_pad.c
index 27bb6a91de5f..c9a0bcaba2e4 100644
--- a/drivers/acpi/acpi_pad.c
+++ b/drivers/acpi/acpi_pad.c
@@ -1,21 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* acpi_pad.c ACPI Processor Aggregator Driver
*
* Copyright (c) 2009, Intel Corporation.
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2, as published by the Free Software Foundation.
- *
- * This program is distributed in the hope it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
- *
*/
#include <linux/kernel.h>
@@ -24,26 +11,32 @@
#include <linux/init.h>
#include <linux/types.h>
#include <linux/kthread.h>
+#include <uapi/linux/sched/types.h>
#include <linux/freezer.h>
#include <linux/cpu.h>
-#include <linux/clockchips.h>
+#include <linux/tick.h>
#include <linux/slab.h>
-#include <acpi/acpi_bus.h>
-#include <acpi/acpi_drivers.h>
+#include <linux/acpi.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <asm/cpuid/api.h>
#include <asm/mwait.h>
+#include <xen/xen.h>
#define ACPI_PROCESSOR_AGGREGATOR_CLASS "acpi_pad"
#define ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME "Processor Aggregator"
#define ACPI_PROCESSOR_AGGREGATOR_NOTIFY 0x80
+
+#define ACPI_PROCESSOR_AGGREGATOR_STATUS_SUCCESS 0
+#define ACPI_PROCESSOR_AGGREGATOR_STATUS_NO_ACTION 1
+
static DEFINE_MUTEX(isolated_cpus_lock);
static DEFINE_MUTEX(round_robin_lock);
-static unsigned long power_saving_mwait_eax;
+static unsigned int power_saving_mwait_eax;
static unsigned char tsc_detected_unstable;
static unsigned char tsc_marked_unstable;
-static unsigned char lapic_detected_unstable;
-static unsigned char lapic_marked_unstable;
static void power_saving_mwait_init(void)
{
@@ -54,10 +47,8 @@ static void power_saving_mwait_init(void)
if (!boot_cpu_has(X86_FEATURE_MWAIT))
return;
- if (boot_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
- return;
- cpuid(CPUID_MWAIT_LEAF, &eax, &ebx, &ecx, &edx);
+ cpuid(CPUID_LEAF_MWAIT, &eax, &ebx, &ecx, &edx);
if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED) ||
!(ecx & CPUID5_ECX_INTERRUPT_BREAK))
@@ -75,21 +66,21 @@ static void power_saving_mwait_init(void)
#if defined(CONFIG_X86)
switch (boot_cpu_data.x86_vendor) {
+ case X86_VENDOR_HYGON:
case X86_VENDOR_AMD:
case X86_VENDOR_INTEL:
+ case X86_VENDOR_ZHAOXIN:
+ case X86_VENDOR_CENTAUR:
/*
* AMD Fam10h TSC will tick in all
* C/P/S0/S1 states when this bit is set.
*/
if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
tsc_detected_unstable = 1;
- if (!boot_cpu_has(X86_FEATURE_ARAT))
- lapic_detected_unstable = 1;
break;
default:
- /* TSC & LAPIC could halt in idle */
+ /* TSC could halt in idle */
tsc_detected_unstable = 1;
- lapic_detected_unstable = 1;
}
#endif
}
@@ -103,7 +94,7 @@ static void round_robin_cpu(unsigned int tsk_index)
cpumask_var_t tmp;
int cpu;
unsigned long min_weight = -1;
- unsigned long uninitialized_var(preferred_cpu);
+ unsigned long preferred_cpu;
if (!alloc_cpumask_var(&tmp, GFP_KERNEL))
return;
@@ -111,13 +102,14 @@ static void round_robin_cpu(unsigned int tsk_index)
mutex_lock(&round_robin_lock);
cpumask_clear(tmp);
for_each_cpu(cpu, pad_busy_cpus)
- cpumask_or(tmp, tmp, topology_thread_cpumask(cpu));
+ cpumask_or(tmp, tmp, topology_sibling_cpumask(cpu));
cpumask_andnot(tmp, cpu_online_mask, tmp);
- /* avoid HT sibilings if possible */
+ /* avoid HT siblings if possible */
if (cpumask_empty(tmp))
cpumask_andnot(tmp, cpu_online_mask, pad_busy_cpus);
if (cpumask_empty(tmp)) {
mutex_unlock(&round_robin_lock);
+ free_cpumask_var(tmp);
return;
}
for_each_cpu(cpu, tmp) {
@@ -135,34 +127,36 @@ static void round_robin_cpu(unsigned int tsk_index)
mutex_unlock(&round_robin_lock);
set_cpus_allowed_ptr(current, cpumask_of(preferred_cpu));
+
+ free_cpumask_var(tmp);
}
static void exit_round_robin(unsigned int tsk_index)
{
struct cpumask *pad_busy_cpus = to_cpumask(pad_busy_cpus_bits);
- cpumask_clear_cpu(tsk_in_cpu[tsk_index], pad_busy_cpus);
- tsk_in_cpu[tsk_index] = -1;
+
+ if (tsk_in_cpu[tsk_index] != -1) {
+ cpumask_clear_cpu(tsk_in_cpu[tsk_index], pad_busy_cpus);
+ tsk_in_cpu[tsk_index] = -1;
+ }
}
static unsigned int idle_pct = 5; /* percentage */
static unsigned int round_robin_time = 1; /* second */
static int power_saving_thread(void *data)
{
- struct sched_param param = {.sched_priority = 1};
int do_sleep;
unsigned int tsk_index = (unsigned long)data;
u64 last_jiffies = 0;
- sched_setscheduler(current, SCHED_RR, &param);
+ sched_set_fifo_low(current);
while (!kthread_should_stop()) {
- int cpu;
- u64 expire_time;
-
- try_to_freeze();
+ unsigned long expire_time;
/* round robin to cpus */
- if (last_jiffies + round_robin_time * HZ < jiffies) {
+ expire_time = last_jiffies + round_robin_time * HZ;
+ if (time_before(expire_time, jiffies)) {
last_jiffies = jiffies;
round_robin_cpu(tsk_index);
}
@@ -177,34 +171,24 @@ static int power_saving_thread(void *data)
mark_tsc_unstable("TSC halts in idle");
tsc_marked_unstable = 1;
}
- if (lapic_detected_unstable && !lapic_marked_unstable) {
- int i;
- /* LAPIC could halt in idle, so notify users */
- for_each_online_cpu(i)
- clockevents_notify(
- CLOCK_EVT_NOTIFY_BROADCAST_ON,
- &i);
- lapic_marked_unstable = 1;
- }
local_irq_disable();
- cpu = smp_processor_id();
- if (lapic_marked_unstable)
- clockevents_notify(
- CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu);
+
+ perf_lopwr_cb(true);
+
+ tick_broadcast_enable();
+ tick_broadcast_enter();
stop_critical_timings();
- __monitor((void *)&current_thread_info()->flags, 0, 0);
- smp_mb();
- if (!need_resched())
- __mwait(power_saving_mwait_eax, 1);
+ mwait_idle_with_hints(power_saving_mwait_eax, 1);
start_critical_timings();
- if (lapic_marked_unstable)
- clockevents_notify(
- CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu);
+ tick_broadcast_exit();
+
+ perf_lopwr_cb(false);
+
local_irq_enable();
- if (jiffies > expire_time) {
+ if (time_before(expire_time, jiffies)) {
do_sleep = 1;
break;
}
@@ -219,8 +203,15 @@ static int power_saving_thread(void *data)
* borrow CPU time from this CPU and cause RT task use > 95%
* CPU time. To make 'avoid starvation' work, takes a nap here.
*/
- if (do_sleep)
+ if (unlikely(do_sleep))
schedule_timeout_killable(HZ * idle_pct / 100);
+
+ /* If an external event has set the need_resched flag, then
+ * we need to deal with it, or this loop will continue to
+ * spin without calling __mwait().
+ */
+ if (unlikely(need_resched()))
+ schedule();
}
exit_round_robin(tsk_index);
@@ -231,16 +222,19 @@ static struct task_struct *ps_tsks[NR_CPUS];
static unsigned int ps_tsk_num;
static int create_power_saving_task(void)
{
- int rc = -ENOMEM;
+ int rc;
ps_tsks[ps_tsk_num] = kthread_run(power_saving_thread,
(void *)(unsigned long)ps_tsk_num,
"acpi_pad/%d", ps_tsk_num);
- rc = PTR_RET(ps_tsks[ps_tsk_num]);
- if (!rc)
- ps_tsk_num++;
- else
+
+ if (IS_ERR(ps_tsks[ps_tsk_num])) {
+ rc = PTR_ERR(ps_tsks[ps_tsk_num]);
ps_tsks[ps_tsk_num] = NULL;
+ } else {
+ rc = 0;
+ ps_tsk_num++;
+ }
return rc;
}
@@ -269,12 +263,12 @@ static void set_power_saving_task_num(unsigned int num)
static void acpi_pad_idle_cpus(unsigned int num_cpus)
{
- get_online_cpus();
+ cpus_read_lock();
num_cpus = min_t(unsigned int, num_cpus, num_online_cpus());
set_power_saving_task_num(num_cpus);
- put_online_cpus();
+ cpus_read_unlock();
}
static uint32_t acpi_pad_idle_cpus_num(void)
@@ -282,10 +276,11 @@ static uint32_t acpi_pad_idle_cpus_num(void)
return ps_tsk_num;
}
-static ssize_t acpi_pad_rrtime_store(struct device *dev,
+static ssize_t rrtime_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned long num;
+
if (kstrtoul(buf, 0, &num))
return -EINVAL;
if (num < 1 || num >= 100)
@@ -296,19 +291,18 @@ static ssize_t acpi_pad_rrtime_store(struct device *dev,
return count;
}
-static ssize_t acpi_pad_rrtime_show(struct device *dev,
+static ssize_t rrtime_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- return scnprintf(buf, PAGE_SIZE, "%d\n", round_robin_time);
+ return sysfs_emit(buf, "%d\n", round_robin_time);
}
-static DEVICE_ATTR(rrtime, S_IRUGO|S_IWUSR,
- acpi_pad_rrtime_show,
- acpi_pad_rrtime_store);
+static DEVICE_ATTR_RW(rrtime);
-static ssize_t acpi_pad_idlepct_store(struct device *dev,
+static ssize_t idlepct_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned long num;
+
if (kstrtoul(buf, 0, &num))
return -EINVAL;
if (num < 1 || num >= 100)
@@ -319,19 +313,18 @@ static ssize_t acpi_pad_idlepct_store(struct device *dev,
return count;
}
-static ssize_t acpi_pad_idlepct_show(struct device *dev,
+static ssize_t idlepct_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- return scnprintf(buf, PAGE_SIZE, "%d\n", idle_pct);
+ return sysfs_emit(buf, "%d\n", idle_pct);
}
-static DEVICE_ATTR(idlepct, S_IRUGO|S_IWUSR,
- acpi_pad_idlepct_show,
- acpi_pad_idlepct_store);
+static DEVICE_ATTR_RW(idlepct);
-static ssize_t acpi_pad_idlecpus_store(struct device *dev,
+static ssize_t idlecpus_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
unsigned long num;
+
if (kstrtoul(buf, 0, &num))
return -EINVAL;
mutex_lock(&isolated_cpus_lock);
@@ -340,46 +333,23 @@ static ssize_t acpi_pad_idlecpus_store(struct device *dev,
return count;
}
-static ssize_t acpi_pad_idlecpus_show(struct device *dev,
+static ssize_t idlecpus_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- int n = 0;
- n = cpumask_scnprintf(buf, PAGE_SIZE-2, to_cpumask(pad_busy_cpus_bits));
- buf[n++] = '\n';
- buf[n] = '\0';
- return n;
+ return cpumap_print_to_pagebuf(false, buf,
+ to_cpumask(pad_busy_cpus_bits));
}
-static DEVICE_ATTR(idlecpus, S_IRUGO|S_IWUSR,
- acpi_pad_idlecpus_show,
- acpi_pad_idlecpus_store);
-static int acpi_pad_add_sysfs(struct acpi_device *device)
-{
- int result;
+static DEVICE_ATTR_RW(idlecpus);
- result = device_create_file(&device->dev, &dev_attr_idlecpus);
- if (result)
- return -ENODEV;
- result = device_create_file(&device->dev, &dev_attr_idlepct);
- if (result) {
- device_remove_file(&device->dev, &dev_attr_idlecpus);
- return -ENODEV;
- }
- result = device_create_file(&device->dev, &dev_attr_rrtime);
- if (result) {
- device_remove_file(&device->dev, &dev_attr_idlecpus);
- device_remove_file(&device->dev, &dev_attr_idlepct);
- return -ENODEV;
- }
- return 0;
-}
+static struct attribute *acpi_pad_attrs[] = {
+ &dev_attr_idlecpus.attr,
+ &dev_attr_idlepct.attr,
+ &dev_attr_rrtime.attr,
+ NULL
+};
-static void acpi_pad_remove_sysfs(struct acpi_device *device)
-{
- device_remove_file(&device->dev, &dev_attr_idlecpus);
- device_remove_file(&device->dev, &dev_attr_idlepct);
- device_remove_file(&device->dev, &dev_attr_rrtime);
-}
+ATTRIBUTE_GROUPS(acpi_pad);
/*
* Query firmware how many CPUs should be idle
@@ -409,52 +379,44 @@ static int acpi_pad_pur(acpi_handle handle)
return num;
}
-/* Notify firmware how many CPUs are idle */
-static void acpi_pad_ost(acpi_handle handle, int stat,
- uint32_t idle_cpus)
-{
- union acpi_object params[3] = {
- {.type = ACPI_TYPE_INTEGER,},
- {.type = ACPI_TYPE_INTEGER,},
- {.type = ACPI_TYPE_BUFFER,},
- };
- struct acpi_object_list arg_list = {3, params};
-
- params[0].integer.value = ACPI_PROCESSOR_AGGREGATOR_NOTIFY;
- params[1].integer.value = stat;
- params[2].buffer.length = 4;
- params[2].buffer.pointer = (void *)&idle_cpus;
- acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
-}
-
static void acpi_pad_handle_notify(acpi_handle handle)
{
int num_cpus;
uint32_t idle_cpus;
+ struct acpi_buffer param = {
+ .length = 4,
+ .pointer = (void *)&idle_cpus,
+ };
+ u32 status;
mutex_lock(&isolated_cpus_lock);
num_cpus = acpi_pad_pur(handle);
if (num_cpus < 0) {
- mutex_unlock(&isolated_cpus_lock);
- return;
+ /* The ACPI specification says that if no action was performed when
+ * processing the _PUR object, _OST should still be evaluated, albeit
+ * with a different status code.
+ */
+ status = ACPI_PROCESSOR_AGGREGATOR_STATUS_NO_ACTION;
+ } else {
+ status = ACPI_PROCESSOR_AGGREGATOR_STATUS_SUCCESS;
+ acpi_pad_idle_cpus(num_cpus);
}
- acpi_pad_idle_cpus(num_cpus);
+
idle_cpus = acpi_pad_idle_cpus_num();
- acpi_pad_ost(handle, 0, idle_cpus);
+ acpi_evaluate_ost(handle, ACPI_PROCESSOR_AGGREGATOR_NOTIFY, status, &param);
mutex_unlock(&isolated_cpus_lock);
}
static void acpi_pad_notify(acpi_handle handle, u32 event,
void *data)
{
- struct acpi_device *device = data;
+ struct acpi_device *adev = data;
switch (event) {
case ACPI_PROCESSOR_AGGREGATOR_NOTIFY:
acpi_pad_handle_notify(handle);
- acpi_bus_generate_proc_event(device, event, 0);
- acpi_bus_generate_netlink_event(device->pnp.device_class,
- dev_name(&device->dev), event, 0);
+ acpi_bus_generate_netlink_event(adev->pnp.device_class,
+ dev_name(&adev->dev), event, 0);
break;
default:
pr_warn("Unsupported event [0x%x]\n", event);
@@ -462,36 +424,33 @@ static void acpi_pad_notify(acpi_handle handle, u32 event,
}
}
-static int acpi_pad_add(struct acpi_device *device)
+static int acpi_pad_probe(struct platform_device *pdev)
{
+ struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
acpi_status status;
- strcpy(acpi_device_name(device), ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME);
- strcpy(acpi_device_class(device), ACPI_PROCESSOR_AGGREGATOR_CLASS);
+ strscpy(acpi_device_name(adev), ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME);
+ strscpy(acpi_device_class(adev), ACPI_PROCESSOR_AGGREGATOR_CLASS);
- if (acpi_pad_add_sysfs(device))
- return -ENODEV;
+ status = acpi_install_notify_handler(adev->handle,
+ ACPI_DEVICE_NOTIFY, acpi_pad_notify, adev);
- status = acpi_install_notify_handler(device->handle,
- ACPI_DEVICE_NOTIFY, acpi_pad_notify, device);
- if (ACPI_FAILURE(status)) {
- acpi_pad_remove_sysfs(device);
+ if (ACPI_FAILURE(status))
return -ENODEV;
- }
return 0;
}
-static int acpi_pad_remove(struct acpi_device *device)
+static void acpi_pad_remove(struct platform_device *pdev)
{
+ struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
+
mutex_lock(&isolated_cpus_lock);
acpi_pad_idle_cpus(0);
mutex_unlock(&isolated_cpus_lock);
- acpi_remove_notify_handler(device->handle,
+ acpi_remove_notify_handler(adev->handle,
ACPI_DEVICE_NOTIFY, acpi_pad_notify);
- acpi_pad_remove_sysfs(device);
- return 0;
}
static const struct acpi_device_id pad_device_ids[] = {
@@ -500,28 +459,32 @@ static const struct acpi_device_id pad_device_ids[] = {
};
MODULE_DEVICE_TABLE(acpi, pad_device_ids);
-static struct acpi_driver acpi_pad_driver = {
- .name = "processor_aggregator",
- .class = ACPI_PROCESSOR_AGGREGATOR_CLASS,
- .ids = pad_device_ids,
- .ops = {
- .add = acpi_pad_add,
- .remove = acpi_pad_remove,
+static struct platform_driver acpi_pad_driver = {
+ .probe = acpi_pad_probe,
+ .remove = acpi_pad_remove,
+ .driver = {
+ .dev_groups = acpi_pad_groups,
+ .name = "processor_aggregator",
+ .acpi_match_table = pad_device_ids,
},
};
static int __init acpi_pad_init(void)
{
+ /* Xen ACPI PAD is used when running as Xen Dom0. */
+ if (xen_initial_domain())
+ return -ENODEV;
+
power_saving_mwait_init();
if (power_saving_mwait_eax == 0)
return -EINVAL;
- return acpi_bus_register_driver(&acpi_pad_driver);
+ return platform_driver_register(&acpi_pad_driver);
}
static void __exit acpi_pad_exit(void)
{
- acpi_bus_unregister_driver(&acpi_pad_driver);
+ platform_driver_unregister(&acpi_pad_driver);
}
module_init(acpi_pad_init);
generated by cgit (git 2.34.1) at 2025-12-25 05:02:44 +0000