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 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 get_online_cpus(); 54 for_each_online_cpu(cpu) { 55 dev = get_cpu_device(cpu); 56 kobject_uevent(&dev->kobj, KOBJ_CHANGE); 57 } 58 put_online_cpus(); 59 } 60 61 static void __ref sclp_cpu_change_notify(struct work_struct *work) 62 { 63 smp_rescan_cpus(); 64 } 65 66 static void sclp_conf_receiver_fn(struct evbuf_header *evbuf) 67 { 68 struct conf_mgm_data *cdata; 69 70 cdata = (struct conf_mgm_data *)(evbuf + 1); 71 switch (cdata->ev_qualifier) { 72 case EV_QUAL_CPU_CHANGE: 73 schedule_work(&sclp_cpu_change_work); 74 break; 75 case EV_QUAL_CAP_CHANGE: 76 schedule_work(&sclp_cpu_capability_work); 77 break; 78 } 79 } 80 81 static struct sclp_register sclp_conf_register = 82 { 83 #ifdef CONFIG_SCLP_OFB 84 .send_mask = EVTYP_CONFMGMDATA_MASK, 85 #endif 86 .receive_mask = EVTYP_CONFMGMDATA_MASK, 87 .receiver_fn = sclp_conf_receiver_fn, 88 }; 89 90 #ifdef CONFIG_SCLP_OFB 91 static int sclp_ofb_send_req(char *ev_data, size_t len) 92 { 93 static DEFINE_MUTEX(send_mutex); 94 struct sclp_ofb_sccb *sccb; 95 int rc, response; 96 97 if (len > OFB_DATA_MAX) 98 return -EINVAL; 99 sccb = (struct sclp_ofb_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA); 100 if (!sccb) 101 return -ENOMEM; 102 /* Setup SCCB for Control-Program Identification */ 103 sccb->header.length = sizeof(struct sclp_ofb_sccb); 104 sccb->ofb_evbuf.header.length = sizeof(struct sclp_ofb_evbuf); 105 sccb->ofb_evbuf.header.type = EVTYP_CONFMGMDATA; 106 sccb->ofb_evbuf.cm_data.ev_qualifier = EV_QUAL_OPEN4BUSINESS; 107 memcpy(sccb->ofb_evbuf.ev_data, ev_data, len); 108 109 if (!(sclp_conf_register.sclp_receive_mask & EVTYP_CONFMGMDATA_MASK)) 110 pr_warn("SCLP receiver did not register to receive " 111 "Configuration Management Data Events.\n"); 112 113 mutex_lock(&send_mutex); 114 rc = sclp_sync_request(SCLP_CMDW_WRITE_EVENT_DATA, sccb); 115 mutex_unlock(&send_mutex); 116 if (rc) 117 goto out; 118 response = sccb->header.response_code; 119 if (response != 0x0020) { 120 pr_err("Open for Business request failed with response code " 121 "0x%04x\n", response); 122 rc = -EIO; 123 } 124 out: 125 free_page((unsigned long)sccb); 126 return rc; 127 } 128 129 static ssize_t sysfs_ofb_data_write(struct file *filp, struct kobject *kobj, 130 struct bin_attribute *bin_attr, 131 char *buf, loff_t off, size_t count) 132 { 133 int rc; 134 135 rc = sclp_ofb_send_req(buf, count); 136 return rc ?: count; 137 } 138 139 static const struct bin_attribute ofb_bin_attr = { 140 .attr = { 141 .name = "event_data", 142 .mode = S_IWUSR, 143 }, 144 .write = sysfs_ofb_data_write, 145 }; 146 #endif 147 148 static int __init sclp_ofb_setup(void) 149 { 150 #ifdef CONFIG_SCLP_OFB 151 struct kset *ofb_kset; 152 int rc; 153 154 ofb_kset = kset_create_and_add("ofb", NULL, firmware_kobj); 155 if (!ofb_kset) 156 return -ENOMEM; 157 rc = sysfs_create_bin_file(&ofb_kset->kobj, &ofb_bin_attr); 158 if (rc) { 159 kset_unregister(ofb_kset); 160 return rc; 161 } 162 #endif 163 return 0; 164 } 165 166 static int __init sclp_conf_init(void) 167 { 168 int rc; 169 170 INIT_WORK(&sclp_cpu_capability_work, sclp_cpu_capability_notify); 171 INIT_WORK(&sclp_cpu_change_work, sclp_cpu_change_notify); 172 rc = sclp_register(&sclp_conf_register); 173 if (rc) 174 return rc; 175 return sclp_ofb_setup(); 176 } 177 178 __initcall(sclp_conf_init); 179