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