1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * PowerNV OPAL IPMI driver 4 * 5 * Copyright 2014 IBM Corp. 6 */ 7 8 #define pr_fmt(fmt) "ipmi-powernv: " fmt 9 10 #include <linux/ipmi_smi.h> 11 #include <linux/list.h> 12 #include <linux/module.h> 13 #include <linux/of.h> 14 #include <linux/of_irq.h> 15 #include <linux/interrupt.h> 16 17 #include <asm/opal.h> 18 19 20 struct ipmi_smi_powernv { 21 u64 interface_id; 22 struct ipmi_smi *intf; 23 unsigned int irq; 24 25 /** 26 * We assume that there can only be one outstanding request, so 27 * keep the pending message in cur_msg. We protect this from concurrent 28 * updates through send & recv calls, (and consequently opal_msg, which 29 * is in-use when cur_msg is set) with msg_lock 30 */ 31 spinlock_t msg_lock; 32 struct ipmi_smi_msg *cur_msg; 33 struct opal_ipmi_msg *opal_msg; 34 }; 35 36 static int ipmi_powernv_start_processing(void *send_info, struct ipmi_smi *intf) 37 { 38 struct ipmi_smi_powernv *smi = send_info; 39 40 smi->intf = intf; 41 return 0; 42 } 43 44 static void send_error_reply(struct ipmi_smi_powernv *smi, 45 struct ipmi_smi_msg *msg, u8 completion_code) 46 { 47 msg->rsp[0] = msg->data[0] | 0x4; 48 msg->rsp[1] = msg->data[1]; 49 msg->rsp[2] = completion_code; 50 msg->rsp_size = 3; 51 ipmi_smi_msg_received(smi->intf, msg); 52 } 53 54 static void ipmi_powernv_send(void *send_info, struct ipmi_smi_msg *msg) 55 { 56 struct ipmi_smi_powernv *smi = send_info; 57 struct opal_ipmi_msg *opal_msg; 58 unsigned long flags; 59 int comp, rc; 60 size_t size; 61 62 /* ensure data_len will fit in the opal_ipmi_msg buffer... */ 63 if (msg->data_size > IPMI_MAX_MSG_LENGTH) { 64 comp = IPMI_REQ_LEN_EXCEEDED_ERR; 65 goto err; 66 } 67 68 /* ... and that we at least have netfn and cmd bytes */ 69 if (msg->data_size < 2) { 70 comp = IPMI_REQ_LEN_INVALID_ERR; 71 goto err; 72 } 73 74 spin_lock_irqsave(&smi->msg_lock, flags); 75 76 if (smi->cur_msg) { 77 comp = IPMI_NODE_BUSY_ERR; 78 goto err_unlock; 79 } 80 81 /* format our data for the OPAL API */ 82 opal_msg = smi->opal_msg; 83 opal_msg->version = OPAL_IPMI_MSG_FORMAT_VERSION_1; 84 opal_msg->netfn = msg->data[0]; 85 opal_msg->cmd = msg->data[1]; 86 if (msg->data_size > 2) 87 memcpy(opal_msg->data, msg->data + 2, msg->data_size - 2); 88 89 /* data_size already includes the netfn and cmd bytes */ 90 size = sizeof(*opal_msg) + msg->data_size - 2; 91 92 pr_devel("%s: opal_ipmi_send(0x%llx, %p, %ld)\n", __func__, 93 smi->interface_id, opal_msg, size); 94 rc = opal_ipmi_send(smi->interface_id, opal_msg, size); 95 pr_devel("%s: -> %d\n", __func__, rc); 96 97 if (!rc) { 98 smi->cur_msg = msg; 99 spin_unlock_irqrestore(&smi->msg_lock, flags); 100 return; 101 } 102 103 comp = IPMI_ERR_UNSPECIFIED; 104 err_unlock: 105 spin_unlock_irqrestore(&smi->msg_lock, flags); 106 err: 107 send_error_reply(smi, msg, comp); 108 } 109 110 static int ipmi_powernv_recv(struct ipmi_smi_powernv *smi) 111 { 112 struct opal_ipmi_msg *opal_msg; 113 struct ipmi_smi_msg *msg; 114 unsigned long flags; 115 uint64_t size; 116 int rc; 117 118 pr_devel("%s: opal_ipmi_recv(%llx, msg, sz)\n", __func__, 119 smi->interface_id); 120 121 spin_lock_irqsave(&smi->msg_lock, flags); 122 123 if (!smi->cur_msg) { 124 spin_unlock_irqrestore(&smi->msg_lock, flags); 125 pr_warn("no current message?\n"); 126 return 0; 127 } 128 129 msg = smi->cur_msg; 130 opal_msg = smi->opal_msg; 131 132 size = cpu_to_be64(sizeof(*opal_msg) + IPMI_MAX_MSG_LENGTH); 133 134 rc = opal_ipmi_recv(smi->interface_id, 135 opal_msg, 136 &size); 137 size = be64_to_cpu(size); 138 pr_devel("%s: -> %d (size %lld)\n", __func__, 139 rc, rc == 0 ? size : 0); 140 if (rc) { 141 /* If came via the poll, and response was not yet ready */ 142 if (rc == OPAL_EMPTY) { 143 spin_unlock_irqrestore(&smi->msg_lock, flags); 144 return 0; 145 } 146 147 smi->cur_msg = NULL; 148 spin_unlock_irqrestore(&smi->msg_lock, flags); 149 send_error_reply(smi, msg, IPMI_ERR_UNSPECIFIED); 150 return 0; 151 } 152 153 if (size < sizeof(*opal_msg)) { 154 spin_unlock_irqrestore(&smi->msg_lock, flags); 155 pr_warn("unexpected IPMI message size %lld\n", size); 156 return 0; 157 } 158 159 if (opal_msg->version != OPAL_IPMI_MSG_FORMAT_VERSION_1) { 160 spin_unlock_irqrestore(&smi->msg_lock, flags); 161 pr_warn("unexpected IPMI message format (version %d)\n", 162 opal_msg->version); 163 return 0; 164 } 165 166 msg->rsp[0] = opal_msg->netfn; 167 msg->rsp[1] = opal_msg->cmd; 168 if (size > sizeof(*opal_msg)) 169 memcpy(&msg->rsp[2], opal_msg->data, size - sizeof(*opal_msg)); 170 msg->rsp_size = 2 + size - sizeof(*opal_msg); 171 172 smi->cur_msg = NULL; 173 spin_unlock_irqrestore(&smi->msg_lock, flags); 174 ipmi_smi_msg_received(smi->intf, msg); 175 return 0; 176 } 177 178 static void ipmi_powernv_request_events(void *send_info) 179 { 180 } 181 182 static void ipmi_powernv_set_run_to_completion(void *send_info, 183 bool run_to_completion) 184 { 185 } 186 187 static void ipmi_powernv_poll(void *send_info) 188 { 189 struct ipmi_smi_powernv *smi = send_info; 190 191 ipmi_powernv_recv(smi); 192 } 193 194 static const struct ipmi_smi_handlers ipmi_powernv_smi_handlers = { 195 .owner = THIS_MODULE, 196 .start_processing = ipmi_powernv_start_processing, 197 .sender = ipmi_powernv_send, 198 .request_events = ipmi_powernv_request_events, 199 .set_run_to_completion = ipmi_powernv_set_run_to_completion, 200 .poll = ipmi_powernv_poll, 201 }; 202 203 static irqreturn_t ipmi_opal_event(int irq, void *data) 204 { 205 struct ipmi_smi_powernv *smi = data; 206 207 ipmi_powernv_recv(smi); 208 return IRQ_HANDLED; 209 } 210 211 static int ipmi_powernv_probe(struct platform_device *pdev) 212 { 213 struct ipmi_smi_powernv *ipmi; 214 struct device *dev; 215 u32 prop; 216 int rc; 217 218 if (!pdev || !pdev->dev.of_node) 219 return -ENODEV; 220 221 dev = &pdev->dev; 222 223 ipmi = devm_kzalloc(dev, sizeof(*ipmi), GFP_KERNEL); 224 if (!ipmi) 225 return -ENOMEM; 226 227 spin_lock_init(&ipmi->msg_lock); 228 229 rc = of_property_read_u32(dev->of_node, "ibm,ipmi-interface-id", 230 &prop); 231 if (rc) { 232 dev_warn(dev, "No interface ID property\n"); 233 goto err_free; 234 } 235 ipmi->interface_id = prop; 236 237 rc = of_property_read_u32(dev->of_node, "interrupts", &prop); 238 if (rc) { 239 dev_warn(dev, "No interrupts property\n"); 240 goto err_free; 241 } 242 243 ipmi->irq = irq_of_parse_and_map(dev->of_node, 0); 244 if (!ipmi->irq) { 245 dev_info(dev, "Unable to map irq from device tree\n"); 246 ipmi->irq = opal_event_request(prop); 247 } 248 249 rc = request_irq(ipmi->irq, ipmi_opal_event, IRQ_TYPE_LEVEL_HIGH, 250 "opal-ipmi", ipmi); 251 if (rc) { 252 dev_warn(dev, "Unable to request irq\n"); 253 goto err_dispose; 254 } 255 256 ipmi->opal_msg = devm_kmalloc(dev, 257 sizeof(*ipmi->opal_msg) + IPMI_MAX_MSG_LENGTH, 258 GFP_KERNEL); 259 if (!ipmi->opal_msg) { 260 rc = -ENOMEM; 261 goto err_unregister; 262 } 263 264 rc = ipmi_register_smi(&ipmi_powernv_smi_handlers, ipmi, dev, 0); 265 if (rc) { 266 dev_warn(dev, "IPMI SMI registration failed (%d)\n", rc); 267 goto err_free_msg; 268 } 269 270 dev_set_drvdata(dev, ipmi); 271 return 0; 272 273 err_free_msg: 274 devm_kfree(dev, ipmi->opal_msg); 275 err_unregister: 276 free_irq(ipmi->irq, ipmi); 277 err_dispose: 278 irq_dispose_mapping(ipmi->irq); 279 err_free: 280 devm_kfree(dev, ipmi); 281 return rc; 282 } 283 284 static int ipmi_powernv_remove(struct platform_device *pdev) 285 { 286 struct ipmi_smi_powernv *smi = dev_get_drvdata(&pdev->dev); 287 288 ipmi_unregister_smi(smi->intf); 289 free_irq(smi->irq, smi); 290 irq_dispose_mapping(smi->irq); 291 292 return 0; 293 } 294 295 static const struct of_device_id ipmi_powernv_match[] = { 296 { .compatible = "ibm,opal-ipmi" }, 297 { }, 298 }; 299 300 301 static struct platform_driver powernv_ipmi_driver = { 302 .driver = { 303 .name = "ipmi-powernv", 304 .of_match_table = ipmi_powernv_match, 305 }, 306 .probe = ipmi_powernv_probe, 307 .remove = ipmi_powernv_remove, 308 }; 309 310 311 module_platform_driver(powernv_ipmi_driver); 312 313 MODULE_DEVICE_TABLE(of, ipmi_powernv_match); 314 MODULE_DESCRIPTION("powernv IPMI driver"); 315 MODULE_AUTHOR("Jeremy Kerr <jk@ozlabs.org>"); 316 MODULE_LICENSE("GPL"); 317