+++ /dev/null
-What: /sys/firmware/opal/powercap
-Date: August 2017
-Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
-Description: Powercap directory for Powernv (P8, P9) servers
-
- Each folder in this directory contains a
- power-cappable component.
-
-What: /sys/firmware/opal/powercap/system-powercap
- /sys/firmware/opal/powercap/system-powercap/powercap-min
- /sys/firmware/opal/powercap/system-powercap/powercap-max
- /sys/firmware/opal/powercap/system-powercap/powercap-current
-Date: August 2017
-Contact: Linux for PowerPC mailing list <linuxppc-dev@ozlabs.org>
-Description: System powercap directory and attributes applicable for
- Powernv (P8, P9) servers
-
- This directory provides powercap information. It
- contains below sysfs attributes:
-
- - powercap-min : This file provides the minimum
- possible powercap in Watt units
-
- - powercap-max : This file provides the maximum
- possible powercap in Watt units
-
- - powercap-current : This file provides the current
- powercap set on the system. Writing to this file
- creates a request for setting a new-powercap. The
- powercap requested must be between powercap-min
- and powercap-max.
+++ /dev/null
-/*
- * PowerNV OPAL Powercap interface
- *
- * Copyright 2017 IBM Corp.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#define pr_fmt(fmt) "opal-powercap: " fmt
-
-#include <linux/of.h>
-#include <linux/kobject.h>
-#include <linux/slab.h>
-
-#include <asm/opal.h>
-
-DEFINE_MUTEX(powercap_mutex);
-
-static struct kobject *powercap_kobj;
-
-struct powercap_attr {
- u32 handle;
- struct kobj_attribute attr;
-};
-
-static struct pcap {
- struct attribute_group pg;
- struct powercap_attr *pattrs;
-} *pcaps;
-
-static ssize_t powercap_show(struct kobject *kobj, struct kobj_attribute *attr,
- char *buf)
-{
- struct powercap_attr *pcap_attr = container_of(attr,
- struct powercap_attr, attr);
- struct opal_msg msg;
- u32 pcap;
- int ret, token;
-
- token = opal_async_get_token_interruptible();
- if (token < 0) {
- pr_devel("Failed to get token\n");
- return token;
- }
-
- ret = mutex_lock_interruptible(&powercap_mutex);
- if (ret)
- goto out_token;
-
- ret = opal_get_powercap(pcap_attr->handle, token, (u32 *)__pa(&pcap));
- switch (ret) {
- case OPAL_ASYNC_COMPLETION:
- ret = opal_async_wait_response(token, &msg);
- if (ret) {
- pr_devel("Failed to wait for the async response\n");
- ret = -EIO;
- goto out;
- }
- ret = opal_error_code(opal_get_async_rc(msg));
- if (!ret) {
- ret = sprintf(buf, "%u\n", be32_to_cpu(pcap));
- if (ret < 0)
- ret = -EIO;
- }
- break;
- case OPAL_SUCCESS:
- ret = sprintf(buf, "%u\n", be32_to_cpu(pcap));
- if (ret < 0)
- ret = -EIO;
- break;
- default:
- ret = opal_error_code(ret);
- }
-
-out:
- mutex_unlock(&powercap_mutex);
-out_token:
- opal_async_release_token(token);
- return ret;
-}
-
-static ssize_t powercap_store(struct kobject *kobj,
- struct kobj_attribute *attr, const char *buf,
- size_t count)
-{
- struct powercap_attr *pcap_attr = container_of(attr,
- struct powercap_attr, attr);
- struct opal_msg msg;
- u32 pcap;
- int ret, token;
-
- ret = kstrtoint(buf, 0, &pcap);
- if (ret)
- return ret;
-
- token = opal_async_get_token_interruptible();
- if (token < 0) {
- pr_devel("Failed to get token\n");
- return token;
- }
-
- ret = mutex_lock_interruptible(&powercap_mutex);
- if (ret)
- goto out_token;
-
- ret = opal_set_powercap(pcap_attr->handle, token, pcap);
- switch (ret) {
- case OPAL_ASYNC_COMPLETION:
- ret = opal_async_wait_response(token, &msg);
- if (ret) {
- pr_devel("Failed to wait for the async response\n");
- ret = -EIO;
- goto out;
- }
- ret = opal_error_code(opal_get_async_rc(msg));
- if (!ret)
- ret = count;
- break;
- case OPAL_SUCCESS:
- ret = count;
- break;
- default:
- ret = opal_error_code(ret);
- }
-
-out:
- mutex_unlock(&powercap_mutex);
-out_token:
- opal_async_release_token(token);
- return ret;
-}
-
-static void powercap_add_attr(int handle, const char *name,
- struct powercap_attr *attr)
-{
- attr->handle = handle;
- sysfs_attr_init(&attr->attr.attr);
- attr->attr.attr.name = name;
- attr->attr.attr.mode = 0444;
- attr->attr.show = powercap_show;
-}
-
-void __init opal_powercap_init(void)
-{
- struct device_node *powercap, *node;
- int i = 0;
-
- powercap = of_find_compatible_node(NULL, NULL, "ibm,opal-powercap");
- if (!powercap) {
- pr_devel("Powercap node not found\n");
- return;
- }
-
- pcaps = kcalloc(of_get_child_count(powercap), sizeof(*pcaps),
- GFP_KERNEL);
- if (!pcaps)
- return;
-
- powercap_kobj = kobject_create_and_add("powercap", opal_kobj);
- if (!powercap_kobj) {
- pr_warn("Failed to create powercap kobject\n");
- goto out_pcaps;
- }
-
- i = 0;
- for_each_child_of_node(powercap, node) {
- u32 cur, min, max;
- int j = 0;
- bool has_cur = false, has_min = false, has_max = false;
-
- if (!of_property_read_u32(node, "powercap-min", &min)) {
- j++;
- has_min = true;
- }
-
- if (!of_property_read_u32(node, "powercap-max", &max)) {
- j++;
- has_max = true;
- }
-
- if (!of_property_read_u32(node, "powercap-current", &cur)) {
- j++;
- has_cur = true;
- }
-
- pcaps[i].pattrs = kcalloc(j, sizeof(struct powercap_attr),
- GFP_KERNEL);
- if (!pcaps[i].pattrs)
- goto out_pcaps_pattrs;
-
- pcaps[i].pg.attrs = kcalloc(j + 1, sizeof(struct attribute *),
- GFP_KERNEL);
- if (!pcaps[i].pg.attrs) {
- kfree(pcaps[i].pattrs);
- goto out_pcaps_pattrs;
- }
-
- j = 0;
- pcaps[i].pg.name = node->name;
- if (has_min) {
- powercap_add_attr(min, "powercap-min",
- &pcaps[i].pattrs[j]);
- pcaps[i].pg.attrs[j] = &pcaps[i].pattrs[j].attr.attr;
- j++;
- }
-
- if (has_max) {
- powercap_add_attr(max, "powercap-max",
- &pcaps[i].pattrs[j]);
- pcaps[i].pg.attrs[j] = &pcaps[i].pattrs[j].attr.attr;
- j++;
- }
-
- if (has_cur) {
- powercap_add_attr(cur, "powercap-current",
- &pcaps[i].pattrs[j]);
- pcaps[i].pattrs[j].attr.attr.mode |= 0220;
- pcaps[i].pattrs[j].attr.store = powercap_store;
- pcaps[i].pg.attrs[j] = &pcaps[i].pattrs[j].attr.attr;
- j++;
- }
-
- if (sysfs_create_group(powercap_kobj, &pcaps[i].pg)) {
- pr_warn("Failed to create powercap attribute group %s\n",
- pcaps[i].pg.name);
- goto out_pcaps_pattrs;
- }
- i++;
- }
-
- return;
-
-out_pcaps_pattrs:
- while (--i >= 0) {
- kfree(pcaps[i].pattrs);
- kfree(pcaps[i].pg.attrs);
- }
- kobject_put(powercap_kobj);
-out_pcaps:
- kfree(pcaps);
-}