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 int 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 if (rc) { 97 comp = IPMI_ERR_UNSPECIFIED; 98 goto err_unlock; 99 } 100 101 smi->cur_msg = msg; 102 spin_unlock_irqrestore(&smi->msg_lock, flags); 103 return IPMI_CC_NO_ERROR; 104 105 err_unlock: 106 spin_unlock_irqrestore(&smi->msg_lock, flags); 107 err: 108 return comp; 109 } 110 111 static int ipmi_powernv_recv(struct ipmi_smi_powernv *smi) 112 { 113 struct opal_ipmi_msg *opal_msg; 114 struct ipmi_smi_msg *msg; 115 unsigned long flags; 116 uint64_t size; 117 int rc; 118 119 pr_devel("%s: opal_ipmi_recv(%llx, msg, sz)\n", __func__, 120 smi->interface_id); 121 122 spin_lock_irqsave(&smi->msg_lock, flags); 123 124 if (!smi->cur_msg) { 125 spin_unlock_irqrestore(&smi->msg_lock, flags); 126 pr_warn("no current message?\n"); 127 return 0; 128 } 129 130 msg = smi->cur_msg; 131 opal_msg = smi->opal_msg; 132 133 size = cpu_to_be64(sizeof(*opal_msg) + IPMI_MAX_MSG_LENGTH); 134 135 rc = opal_ipmi_recv(smi->interface_id, 136 opal_msg, 137 &size); 138 size = be64_to_cpu(size); 139 pr_devel("%s: -> %d (size %lld)\n", __func__, 140 rc, rc == 0 ? size : 0); 141 if (rc) { 142 /* If came via the poll, and response was not yet ready */ 143 if (rc == OPAL_EMPTY) { 144 spin_unlock_irqrestore(&smi->msg_lock, flags); 145 return 0; 146 } 147 148 smi->cur_msg = NULL; 149 spin_unlock_irqrestore(&smi->msg_lock, flags); 150 send_error_reply(smi, msg, IPMI_ERR_UNSPECIFIED); 151 return 0; 152 } 153 154 if (size < sizeof(*opal_msg)) { 155 spin_unlock_irqrestore(&smi->msg_lock, flags); 156 pr_warn("unexpected IPMI message size %lld\n", size); 157 return 0; 158 } 159 160 if (opal_msg->version != OPAL_IPMI_MSG_FORMAT_VERSION_1) { 161 spin_unlock_irqrestore(&smi->msg_lock, flags); 162 pr_warn("unexpected IPMI message format (version %d)\n", 163 opal_msg->version); 164 return 0; 165 } 166 167 msg->rsp[0] = opal_msg->netfn; 168 msg->rsp[1] = opal_msg->cmd; 169 if (size > sizeof(*opal_msg)) 170 memcpy(&msg->rsp[2], opal_msg->data, size - sizeof(*opal_msg)); 171 msg->rsp_size = 2 + size - sizeof(*opal_msg); 172 173 smi->cur_msg = NULL; 174 spin_unlock_irqrestore(&smi->msg_lock, flags); 175 ipmi_smi_msg_received(smi->intf, msg); 176 return 0; 177 } 178 179 static void ipmi_powernv_request_events(void *send_info) 180 { 181 } 182 183 static void ipmi_powernv_set_run_to_completion(void *send_info, 184 bool run_to_completion) 185 { 186 } 187 188 static void ipmi_powernv_poll(void *send_info) 189 { 190 struct ipmi_smi_powernv *smi = send_info; 191 192 ipmi_powernv_recv(smi); 193 } 194 195 static const struct ipmi_smi_handlers ipmi_powernv_smi_handlers = { 196 .owner = THIS_MODULE, 197 .start_processing = ipmi_powernv_start_processing, 198 .sender = ipmi_powernv_send, 199 .request_events = ipmi_powernv_request_events, 200 .set_run_to_completion = ipmi_powernv_set_run_to_completion, 201 .poll = ipmi_powernv_poll, 202 }; 203 204 static irqreturn_t ipmi_opal_event(int irq, void *data) 205 { 206 struct ipmi_smi_powernv *smi = data; 207 208 ipmi_powernv_recv(smi); 209 return IRQ_HANDLED; 210 } 211 212 static int ipmi_powernv_probe(struct platform_device *pdev) 213 { 214 struct ipmi_smi_powernv *ipmi; 215 struct device *dev; 216 u32 prop; 217 int rc; 218 219 if (!pdev || !pdev->dev.of_node) 220 return -ENODEV; 221 222 dev = &pdev->dev; 223 224 ipmi = devm_kzalloc(dev, sizeof(*ipmi), GFP_KERNEL); 225 if (!ipmi) 226 return -ENOMEM; 227 228 spin_lock_init(&ipmi->msg_lock); 229 230 rc = of_property_read_u32(dev->of_node, "ibm,ipmi-interface-id", 231 &prop); 232 if (rc) { 233 dev_warn(dev, "No interface ID property\n"); 234 goto err_free; 235 } 236 ipmi->interface_id = prop; 237 238 rc = of_property_read_u32(dev->of_node, "interrupts", &prop); 239 if (rc) { 240 dev_warn(dev, "No interrupts property\n"); 241 goto err_free; 242 } 243 244 ipmi->irq = irq_of_parse_and_map(dev->of_node, 0); 245 if (!ipmi->irq) { 246 dev_info(dev, "Unable to map irq from device tree\n"); 247 ipmi->irq = opal_event_request(prop); 248 } 249 250 rc = request_irq(ipmi->irq, ipmi_opal_event, IRQ_TYPE_LEVEL_HIGH, 251 "opal-ipmi", ipmi); 252 if (rc) { 253 dev_warn(dev, "Unable to request irq\n"); 254 goto err_dispose; 255 } 256 257 ipmi->opal_msg = devm_kmalloc(dev, 258 sizeof(*ipmi->opal_msg) + IPMI_MAX_MSG_LENGTH, 259 GFP_KERNEL); 260 if (!ipmi->opal_msg) { 261 rc = -ENOMEM; 262 goto err_unregister; 263 } 264 265 rc = ipmi_register_smi(&ipmi_powernv_smi_handlers, ipmi, dev, 0); 266 if (rc) { 267 dev_warn(dev, "IPMI SMI registration failed (%d)\n", rc); 268 goto err_free_msg; 269 } 270 271 dev_set_drvdata(dev, ipmi); 272 return 0; 273 274 err_free_msg: 275 devm_kfree(dev, ipmi->opal_msg); 276 err_unregister: 277 free_irq(ipmi->irq, ipmi); 278 err_dispose: 279 irq_dispose_mapping(ipmi->irq); 280 err_free: 281 devm_kfree(dev, ipmi); 282 return rc; 283 } 284 285 static void ipmi_powernv_remove(struct platform_device *pdev) 286 { 287 struct ipmi_smi_powernv *smi = dev_get_drvdata(&pdev->dev); 288 289 ipmi_unregister_smi(smi->intf); 290 free_irq(smi->irq, smi); 291 irq_dispose_mapping(smi->irq); 292 } 293 294 static const struct of_device_id ipmi_powernv_match[] = { 295 { .compatible = "ibm,opal-ipmi" }, 296 { }, 297 }; 298 299 300 static struct platform_driver powernv_ipmi_driver = { 301 .driver = { 302 .name = "ipmi-powernv", 303 .of_match_table = ipmi_powernv_match, 304 }, 305 .probe = ipmi_powernv_probe, 306 .remove = ipmi_powernv_remove, 307 }; 308 309 310 module_platform_driver(powernv_ipmi_driver); 311 312 MODULE_DEVICE_TABLE(of, ipmi_powernv_match); 313 MODULE_DESCRIPTION("powernv IPMI driver"); 314 MODULE_AUTHOR("Jeremy Kerr <jk@ozlabs.org>"); 315 MODULE_LICENSE("GPL"); 316