2 * PowerNV OPAL Powercap interface
4 * Copyright 2017 IBM Corp.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
12 #define pr_fmt(fmt) "opal-powercap: " fmt
15 #include <linux/kobject.h>
16 #include <linux/slab.h>
20 DEFINE_MUTEX(powercap_mutex);
22 static struct kobject *powercap_kobj;
24 struct powercap_attr {
26 struct kobj_attribute attr;
30 struct attribute_group pg;
31 struct powercap_attr *pattrs;
34 static ssize_t powercap_show(struct kobject *kobj, struct kobj_attribute *attr,
37 struct powercap_attr *pcap_attr = container_of(attr,
38 struct powercap_attr, attr);
43 token = opal_async_get_token_interruptible();
45 pr_devel("Failed to get token\n");
49 ret = mutex_lock_interruptible(&powercap_mutex);
53 ret = opal_get_powercap(pcap_attr->handle, token, (u32 *)__pa(&pcap));
55 case OPAL_ASYNC_COMPLETION:
56 ret = opal_async_wait_response(token, &msg);
58 pr_devel("Failed to wait for the async response\n");
62 ret = opal_error_code(opal_get_async_rc(msg));
64 ret = sprintf(buf, "%u\n", be32_to_cpu(pcap));
70 ret = sprintf(buf, "%u\n", be32_to_cpu(pcap));
75 ret = opal_error_code(ret);
79 mutex_unlock(&powercap_mutex);
81 opal_async_release_token(token);
85 static ssize_t powercap_store(struct kobject *kobj,
86 struct kobj_attribute *attr, const char *buf,
89 struct powercap_attr *pcap_attr = container_of(attr,
90 struct powercap_attr, attr);
95 ret = kstrtoint(buf, 0, &pcap);
99 token = opal_async_get_token_interruptible();
101 pr_devel("Failed to get token\n");
105 ret = mutex_lock_interruptible(&powercap_mutex);
109 ret = opal_set_powercap(pcap_attr->handle, token, pcap);
111 case OPAL_ASYNC_COMPLETION:
112 ret = opal_async_wait_response(token, &msg);
114 pr_devel("Failed to wait for the async response\n");
118 ret = opal_error_code(opal_get_async_rc(msg));
126 ret = opal_error_code(ret);
130 mutex_unlock(&powercap_mutex);
132 opal_async_release_token(token);
136 static void powercap_add_attr(int handle, const char *name,
137 struct powercap_attr *attr)
139 attr->handle = handle;
140 sysfs_attr_init(&attr->attr.attr);
141 attr->attr.attr.name = name;
142 attr->attr.attr.mode = 0444;
143 attr->attr.show = powercap_show;
146 void __init opal_powercap_init(void)
148 struct device_node *powercap, *node;
151 powercap = of_find_compatible_node(NULL, NULL, "ibm,opal-powercap");
153 pr_devel("Powercap node not found\n");
157 pcaps = kcalloc(of_get_child_count(powercap), sizeof(*pcaps),
162 powercap_kobj = kobject_create_and_add("powercap", opal_kobj);
163 if (!powercap_kobj) {
164 pr_warn("Failed to create powercap kobject\n");
169 for_each_child_of_node(powercap, node) {
172 bool has_cur = false, has_min = false, has_max = false;
174 if (!of_property_read_u32(node, "powercap-min", &min)) {
179 if (!of_property_read_u32(node, "powercap-max", &max)) {
184 if (!of_property_read_u32(node, "powercap-current", &cur)) {
189 pcaps[i].pattrs = kcalloc(j, sizeof(struct powercap_attr),
191 if (!pcaps[i].pattrs)
192 goto out_pcaps_pattrs;
194 pcaps[i].pg.attrs = kcalloc(j + 1, sizeof(struct attribute *),
196 if (!pcaps[i].pg.attrs) {
197 kfree(pcaps[i].pattrs);
198 goto out_pcaps_pattrs;
202 pcaps[i].pg.name = node->name;
204 powercap_add_attr(min, "powercap-min",
205 &pcaps[i].pattrs[j]);
206 pcaps[i].pg.attrs[j] = &pcaps[i].pattrs[j].attr.attr;
211 powercap_add_attr(max, "powercap-max",
212 &pcaps[i].pattrs[j]);
213 pcaps[i].pg.attrs[j] = &pcaps[i].pattrs[j].attr.attr;
218 powercap_add_attr(cur, "powercap-current",
219 &pcaps[i].pattrs[j]);
220 pcaps[i].pattrs[j].attr.attr.mode |= 0220;
221 pcaps[i].pattrs[j].attr.store = powercap_store;
222 pcaps[i].pg.attrs[j] = &pcaps[i].pattrs[j].attr.attr;
226 if (sysfs_create_group(powercap_kobj, &pcaps[i].pg)) {
227 pr_warn("Failed to create powercap attribute group %s\n",
229 goto out_pcaps_pattrs;
238 kfree(pcaps[i].pattrs);
239 kfree(pcaps[i].pg.attrs);
241 kobject_put(powercap_kobj);