1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corp. 2007
4 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
5 */
6
7 #define KMSG_COMPONENT "sclp_config"
8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9
10 #include <linux/init.h>
11 #include <linux/errno.h>
12 #include <linux/cpu.h>
13 #include <linux/device.h>
14 #include <linux/workqueue.h>
15 #include <linux/slab.h>
16 #include <linux/sysfs.h>
17 #include <asm/smp.h>
18
19 #include "sclp.h"
20
21 struct conf_mgm_data {
22 u8 reserved;
23 u8 ev_qualifier;
24 } __attribute__((packed));
25
26 #define OFB_DATA_MAX 64
27
28 struct sclp_ofb_evbuf {
29 struct evbuf_header header;
30 struct conf_mgm_data cm_data;
31 char ev_data[OFB_DATA_MAX];
32 } __packed;
33
34 struct sclp_ofb_sccb {
35 struct sccb_header header;
36 struct sclp_ofb_evbuf ofb_evbuf;
37 } __packed;
38
39 #define EV_QUAL_CPU_CHANGE 1
40 #define EV_QUAL_CAP_CHANGE 3
41 #define EV_QUAL_OPEN4BUSINESS 5
42
43 static struct work_struct sclp_cpu_capability_work;
44 static struct work_struct sclp_cpu_change_work;
45
sclp_cpu_capability_notify(struct work_struct * work)46 static void sclp_cpu_capability_notify(struct work_struct *work)
47 {
48 int cpu;
49 struct device *dev;
50
51 s390_update_cpu_mhz();
52 pr_info("CPU capability may have changed\n");
53 cpus_read_lock();
54 for_each_online_cpu(cpu) {
55 dev = get_cpu_device(cpu);
56 kobject_uevent(&dev->kobj, KOBJ_CHANGE);
57 }
58 cpus_read_unlock();
59 }
60
sclp_cpu_change_notify(struct work_struct * work)61 static void __ref sclp_cpu_change_notify(struct work_struct *work)
62 {
63 lock_device_hotplug();
64 smp_rescan_cpus();
65 unlock_device_hotplug();
66 }
67
sclp_conf_receiver_fn(struct evbuf_header * evbuf)68 static void sclp_conf_receiver_fn(struct evbuf_header *evbuf)
69 {
70 struct conf_mgm_data *cdata;
71
72 cdata = (struct conf_mgm_data *)(evbuf + 1);
73 switch (cdata->ev_qualifier) {
74 case EV_QUAL_CPU_CHANGE:
75 schedule_work(&sclp_cpu_change_work);
76 break;
77 case EV_QUAL_CAP_CHANGE:
78 schedule_work(&sclp_cpu_capability_work);
79 break;
80 }
81 }
82
83 static struct sclp_register sclp_conf_register =
84 {
85 #ifdef CONFIG_SCLP_OFB
86 .send_mask = EVTYP_CONFMGMDATA_MASK,
87 #endif
88 .receive_mask = EVTYP_CONFMGMDATA_MASK,
89 .receiver_fn = sclp_conf_receiver_fn,
90 };
91
92 #ifdef CONFIG_SCLP_OFB
sclp_ofb_send_req(char * ev_data,size_t len)93 static int sclp_ofb_send_req(char *ev_data, size_t len)
94 {
95 static DEFINE_MUTEX(send_mutex);
96 struct sclp_ofb_sccb *sccb;
97 int rc, response;
98
99 if (len > OFB_DATA_MAX)
100 return -EINVAL;
101 sccb = (struct sclp_ofb_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
102 if (!sccb)
103 return -ENOMEM;
104 /* Setup SCCB for Control-Program Identification */
105 sccb->header.length = sizeof(struct sclp_ofb_sccb);
106 sccb->ofb_evbuf.header.length = sizeof(struct sclp_ofb_evbuf);
107 sccb->ofb_evbuf.header.type = EVTYP_CONFMGMDATA;
108 sccb->ofb_evbuf.cm_data.ev_qualifier = EV_QUAL_OPEN4BUSINESS;
109 memcpy(sccb->ofb_evbuf.ev_data, ev_data, len);
110
111 if (!(sclp_conf_register.sclp_receive_mask & EVTYP_CONFMGMDATA_MASK))
112 pr_warn("SCLP receiver did not register to receive "
113 "Configuration Management Data Events.\n");
114
115 mutex_lock(&send_mutex);
116 rc = sclp_sync_request(SCLP_CMDW_WRITE_EVENT_DATA, sccb);
117 mutex_unlock(&send_mutex);
118 if (rc)
119 goto out;
120 response = sccb->header.response_code;
121 if (response != 0x0020) {
122 pr_err("Open for Business request failed with response code "
123 "0x%04x\n", response);
124 rc = -EIO;
125 }
126 out:
127 free_page((unsigned long)sccb);
128 return rc;
129 }
130
sysfs_ofb_data_write(struct file * filp,struct kobject * kobj,struct bin_attribute * bin_attr,char * buf,loff_t off,size_t count)131 static ssize_t sysfs_ofb_data_write(struct file *filp, struct kobject *kobj,
132 struct bin_attribute *bin_attr,
133 char *buf, loff_t off, size_t count)
134 {
135 int rc;
136
137 rc = sclp_ofb_send_req(buf, count);
138 return rc ?: count;
139 }
140
141 static const struct bin_attribute ofb_bin_attr = {
142 .attr = {
143 .name = "event_data",
144 .mode = S_IWUSR,
145 },
146 .write = sysfs_ofb_data_write,
147 };
148 #endif
149
sclp_ofb_setup(void)150 static int __init sclp_ofb_setup(void)
151 {
152 #ifdef CONFIG_SCLP_OFB
153 struct kset *ofb_kset;
154 int rc;
155
156 ofb_kset = kset_create_and_add("ofb", NULL, firmware_kobj);
157 if (!ofb_kset)
158 return -ENOMEM;
159 rc = sysfs_create_bin_file(&ofb_kset->kobj, &ofb_bin_attr);
160 if (rc) {
161 kset_unregister(ofb_kset);
162 return rc;
163 }
164 #endif
165 return 0;
166 }
167
sclp_conf_init(void)168 static int __init sclp_conf_init(void)
169 {
170 int rc;
171
172 INIT_WORK(&sclp_cpu_capability_work, sclp_cpu_capability_notify);
173 INIT_WORK(&sclp_cpu_change_work, sclp_cpu_change_notify);
174 rc = sclp_register(&sclp_conf_register);
175 if (rc)
176 return rc;
177 return sclp_ofb_setup();
178 }
179
180 __initcall(sclp_conf_init);
181