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 ; |
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 ; |
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 | |
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(kobj: &dev->kobj, action: KOBJ_CHANGE); |
56 | } |
57 | cpus_read_unlock(); |
58 | } |
59 | |
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 | |
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(work: &sclp_cpu_change_work); |
75 | break; |
76 | case EV_QUAL_CAP_CHANGE: |
77 | schedule_work(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 |
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 | |
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 | |
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 | |
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(reg: &sclp_conf_register); |
174 | if (rc) |
175 | return rc; |
176 | return sclp_ofb_setup(); |
177 | } |
178 | |
179 | __initcall(sclp_conf_init); |
180 | |