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