1 /* 2 * PowerNV OPAL IPMI driver 3 * 4 * Copyright 2014 IBM Corp. 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published by the Free 8 * Software Foundation; either version 2 of the License, or (at your option) 9 * any later version. 10 */ 11 12 #define pr_fmt(fmt) "ipmi-powernv: " fmt 13 14 #include <linux/ipmi_smi.h> 15 #include <linux/list.h> 16 #include <linux/module.h> 17 #include <linux/of.h> 18 #include <linux/of_irq.h> 19 #include <linux/interrupt.h> 20 21 #include <asm/opal.h> 22 23 24 struct ipmi_smi_powernv { 25 u64 interface_id; 26 struct ipmi_device_id ipmi_id; 27 ipmi_smi_t intf; 28 unsigned int irq; 29 30 /** 31 * We assume that there can only be one outstanding request, so 32 * keep the pending message in cur_msg. We protect this from concurrent 33 * updates through send & recv calls, (and consequently opal_msg, which 34 * is in-use when cur_msg is set) with msg_lock 35 */ 36 spinlock_t msg_lock; 37 struct ipmi_smi_msg *cur_msg; 38 struct opal_ipmi_msg *opal_msg; 39 }; 40 41 static int ipmi_powernv_start_processing(void *send_info, ipmi_smi_t intf) 42 { 43 struct ipmi_smi_powernv *smi = send_info; 44 45 smi->intf = intf; 46 return 0; 47 } 48 49 static void send_error_reply(struct ipmi_smi_powernv *smi, 50 struct ipmi_smi_msg *msg, u8 completion_code) 51 { 52 msg->rsp[0] = msg->data[0] | 0x4; 53 msg->rsp[1] = msg->data[1]; 54 msg->rsp[2] = completion_code; 55 msg->rsp_size = 3; 56 ipmi_smi_msg_received(smi->intf, msg); 57 } 58 59 static void ipmi_powernv_send(void *send_info, struct ipmi_smi_msg *msg) 60 { 61 struct ipmi_smi_powernv *smi = send_info; 62 struct opal_ipmi_msg *opal_msg; 63 unsigned long flags; 64 int comp, rc; 65 size_t size; 66 67 /* ensure data_len will fit in the opal_ipmi_msg buffer... */ 68 if (msg->data_size > IPMI_MAX_MSG_LENGTH) { 69 comp = IPMI_REQ_LEN_EXCEEDED_ERR; 70 goto err; 71 } 72 73 /* ... and that we at least have netfn and cmd bytes */ 74 if (msg->data_size < 2) { 75 comp = IPMI_REQ_LEN_INVALID_ERR; 76 goto err; 77 } 78 79 spin_lock_irqsave(&smi->msg_lock, flags); 80 81 if (smi->cur_msg) { 82 comp = IPMI_NODE_BUSY_ERR; 83 goto err_unlock; 84 } 85 86 /* format our data for the OPAL API */ 87 opal_msg = smi->opal_msg; 88 opal_msg->version = OPAL_IPMI_MSG_FORMAT_VERSION_1; 89 opal_msg->netfn = msg->data[0]; 90 opal_msg->cmd = msg->data[1]; 91 if (msg->data_size > 2) 92 memcpy(opal_msg->data, msg->data + 2, msg->data_size - 2); 93 94 /* data_size already includes the netfn and cmd bytes */ 95 size = sizeof(*opal_msg) + msg->data_size - 2; 96 97 pr_devel("%s: opal_ipmi_send(0x%llx, %p, %ld)\n", __func__, 98 smi->interface_id, opal_msg, size); 99 rc = opal_ipmi_send(smi->interface_id, opal_msg, size); 100 pr_devel("%s: -> %d\n", __func__, rc); 101 102 if (!rc) { 103 smi->cur_msg = msg; 104 spin_unlock_irqrestore(&smi->msg_lock, flags); 105 return; 106 } 107 108 comp = IPMI_ERR_UNSPECIFIED; 109 err_unlock: 110 spin_unlock_irqrestore(&smi->msg_lock, flags); 111 err: 112 send_error_reply(smi, msg, comp); 113 } 114 115 static int ipmi_powernv_recv(struct ipmi_smi_powernv *smi) 116 { 117 struct opal_ipmi_msg *opal_msg; 118 struct ipmi_smi_msg *msg; 119 unsigned long flags; 120 uint64_t size; 121 int rc; 122 123 pr_devel("%s: opal_ipmi_recv(%llx, msg, sz)\n", __func__, 124 smi->interface_id); 125 126 spin_lock_irqsave(&smi->msg_lock, flags); 127 128 if (!smi->cur_msg) { 129 spin_unlock_irqrestore(&smi->msg_lock, flags); 130 pr_warn("no current message?\n"); 131 return 0; 132 } 133 134 msg = smi->cur_msg; 135 opal_msg = smi->opal_msg; 136 137 size = cpu_to_be64(sizeof(*opal_msg) + IPMI_MAX_MSG_LENGTH); 138 139 rc = opal_ipmi_recv(smi->interface_id, 140 opal_msg, 141 &size); 142 size = be64_to_cpu(size); 143 pr_devel("%s: -> %d (size %lld)\n", __func__, 144 rc, rc == 0 ? size : 0); 145 if (rc) { 146 /* If came via the poll, and response was not yet ready */ 147 if (rc == OPAL_EMPTY) { 148 spin_unlock_irqrestore(&smi->msg_lock, flags); 149 return 0; 150 } 151 152 smi->cur_msg = NULL; 153 spin_unlock_irqrestore(&smi->msg_lock, flags); 154 send_error_reply(smi, msg, IPMI_ERR_UNSPECIFIED); 155 return 0; 156 } 157 158 if (size < sizeof(*opal_msg)) { 159 spin_unlock_irqrestore(&smi->msg_lock, flags); 160 pr_warn("unexpected IPMI message size %lld\n", size); 161 return 0; 162 } 163 164 if (opal_msg->version != OPAL_IPMI_MSG_FORMAT_VERSION_1) { 165 spin_unlock_irqrestore(&smi->msg_lock, flags); 166 pr_warn("unexpected IPMI message format (version %d)\n", 167 opal_msg->version); 168 return 0; 169 } 170 171 msg->rsp[0] = opal_msg->netfn; 172 msg->rsp[1] = opal_msg->cmd; 173 if (size > sizeof(*opal_msg)) 174 memcpy(&msg->rsp[2], opal_msg->data, size - sizeof(*opal_msg)); 175 msg->rsp_size = 2 + size - sizeof(*opal_msg); 176 177 smi->cur_msg = NULL; 178 spin_unlock_irqrestore(&smi->msg_lock, flags); 179 ipmi_smi_msg_received(smi->intf, msg); 180 return 0; 181 } 182 183 static void ipmi_powernv_request_events(void *send_info) 184 { 185 } 186 187 static void ipmi_powernv_set_run_to_completion(void *send_info, 188 bool run_to_completion) 189 { 190 } 191 192 static void ipmi_powernv_poll(void *send_info) 193 { 194 struct ipmi_smi_powernv *smi = send_info; 195 196 ipmi_powernv_recv(smi); 197 } 198 199 static struct ipmi_smi_handlers ipmi_powernv_smi_handlers = { 200 .owner = THIS_MODULE, 201 .start_processing = ipmi_powernv_start_processing, 202 .sender = ipmi_powernv_send, 203 .request_events = ipmi_powernv_request_events, 204 .set_run_to_completion = ipmi_powernv_set_run_to_completion, 205 .poll = ipmi_powernv_poll, 206 }; 207 208 static irqreturn_t ipmi_opal_event(int irq, void *data) 209 { 210 struct ipmi_smi_powernv *smi = data; 211 212 ipmi_powernv_recv(smi); 213 return IRQ_HANDLED; 214 } 215 216 static int ipmi_powernv_probe(struct platform_device *pdev) 217 { 218 struct ipmi_smi_powernv *ipmi; 219 struct device *dev; 220 u32 prop; 221 int rc; 222 223 if (!pdev || !pdev->dev.of_node) 224 return -ENODEV; 225 226 dev = &pdev->dev; 227 228 ipmi = devm_kzalloc(dev, sizeof(*ipmi), GFP_KERNEL); 229 if (!ipmi) 230 return -ENOMEM; 231 232 spin_lock_init(&ipmi->msg_lock); 233 234 rc = of_property_read_u32(dev->of_node, "ibm,ipmi-interface-id", 235 &prop); 236 if (rc) { 237 dev_warn(dev, "No interface ID property\n"); 238 goto err_free; 239 } 240 ipmi->interface_id = prop; 241 242 rc = of_property_read_u32(dev->of_node, "interrupts", &prop); 243 if (rc) { 244 dev_warn(dev, "No interrupts property\n"); 245 goto err_free; 246 } 247 248 ipmi->irq = irq_of_parse_and_map(dev->of_node, 0); 249 if (!ipmi->irq) { 250 dev_info(dev, "Unable to map irq from device tree\n"); 251 ipmi->irq = opal_event_request(prop); 252 } 253 254 if (request_irq(ipmi->irq, ipmi_opal_event, IRQ_TYPE_LEVEL_HIGH, 255 "opal-ipmi", ipmi)) { 256 dev_warn(dev, "Unable to request irq\n"); 257 goto err_dispose; 258 } 259 260 ipmi->opal_msg = devm_kmalloc(dev, 261 sizeof(*ipmi->opal_msg) + IPMI_MAX_MSG_LENGTH, 262 GFP_KERNEL); 263 if (!ipmi->opal_msg) { 264 rc = -ENOMEM; 265 goto err_unregister; 266 } 267 268 /* todo: query actual ipmi_device_id */ 269 rc = ipmi_register_smi(&ipmi_powernv_smi_handlers, ipmi, 270 &ipmi->ipmi_id, dev, 0); 271 if (rc) { 272 dev_warn(dev, "IPMI SMI registration failed (%d)\n", rc); 273 goto err_free_msg; 274 } 275 276 dev_set_drvdata(dev, ipmi); 277 return 0; 278 279 err_free_msg: 280 devm_kfree(dev, ipmi->opal_msg); 281 err_unregister: 282 free_irq(ipmi->irq, ipmi); 283 err_dispose: 284 irq_dispose_mapping(ipmi->irq); 285 err_free: 286 devm_kfree(dev, ipmi); 287 return rc; 288 } 289 290 static int ipmi_powernv_remove(struct platform_device *pdev) 291 { 292 struct ipmi_smi_powernv *smi = dev_get_drvdata(&pdev->dev); 293 294 ipmi_unregister_smi(smi->intf); 295 free_irq(smi->irq, smi); 296 irq_dispose_mapping(smi->irq); 297 298 return 0; 299 } 300 301 static const struct of_device_id ipmi_powernv_match[] = { 302 { .compatible = "ibm,opal-ipmi" }, 303 { }, 304 }; 305 306 307 static struct platform_driver powernv_ipmi_driver = { 308 .driver = { 309 .name = "ipmi-powernv", 310 .of_match_table = ipmi_powernv_match, 311 }, 312 .probe = ipmi_powernv_probe, 313 .remove = ipmi_powernv_remove, 314 }; 315 316 317 module_platform_driver(powernv_ipmi_driver); 318 319 MODULE_DEVICE_TABLE(of, ipmi_powernv_match); 320 MODULE_DESCRIPTION("powernv IPMI driver"); 321 MODULE_AUTHOR("Jeremy Kerr <jk@ozlabs.org>"); 322 MODULE_LICENSE("GPL"); 323