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
ipmi_powernv_start_processing(void * send_info,ipmi_smi_t intf)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
send_error_reply(struct ipmi_smi_powernv * smi,struct ipmi_smi_msg * msg,u8 completion_code)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
ipmi_powernv_send(void * send_info,struct ipmi_smi_msg * msg)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
ipmi_powernv_recv(struct ipmi_smi_powernv * smi)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
ipmi_powernv_request_events(void * send_info)183 static void ipmi_powernv_request_events(void *send_info)
184 {
185 }
186
ipmi_powernv_set_run_to_completion(void * send_info,bool run_to_completion)187 static void ipmi_powernv_set_run_to_completion(void *send_info,
188 bool run_to_completion)
189 {
190 }
191
ipmi_powernv_poll(void * send_info)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
ipmi_opal_event(int irq,void * data)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
ipmi_powernv_probe(struct platform_device * pdev)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 rc = request_irq(ipmi->irq, ipmi_opal_event, IRQ_TYPE_LEVEL_HIGH,
255 "opal-ipmi", ipmi);
256 if (rc) {
257 dev_warn(dev, "Unable to request irq\n");
258 goto err_dispose;
259 }
260
261 ipmi->opal_msg = devm_kmalloc(dev,
262 sizeof(*ipmi->opal_msg) + IPMI_MAX_MSG_LENGTH,
263 GFP_KERNEL);
264 if (!ipmi->opal_msg) {
265 rc = -ENOMEM;
266 goto err_unregister;
267 }
268
269 /* todo: query actual ipmi_device_id */
270 rc = ipmi_register_smi(&ipmi_powernv_smi_handlers, ipmi,
271 &ipmi->ipmi_id, dev, 0);
272 if (rc) {
273 dev_warn(dev, "IPMI SMI registration failed (%d)\n", rc);
274 goto err_free_msg;
275 }
276
277 dev_set_drvdata(dev, ipmi);
278 return 0;
279
280 err_free_msg:
281 devm_kfree(dev, ipmi->opal_msg);
282 err_unregister:
283 free_irq(ipmi->irq, ipmi);
284 err_dispose:
285 irq_dispose_mapping(ipmi->irq);
286 err_free:
287 devm_kfree(dev, ipmi);
288 return rc;
289 }
290
ipmi_powernv_remove(struct platform_device * pdev)291 static int ipmi_powernv_remove(struct platform_device *pdev)
292 {
293 struct ipmi_smi_powernv *smi = dev_get_drvdata(&pdev->dev);
294
295 ipmi_unregister_smi(smi->intf);
296 free_irq(smi->irq, smi);
297 irq_dispose_mapping(smi->irq);
298
299 return 0;
300 }
301
302 static const struct of_device_id ipmi_powernv_match[] = {
303 { .compatible = "ibm,opal-ipmi" },
304 { },
305 };
306
307
308 static struct platform_driver powernv_ipmi_driver = {
309 .driver = {
310 .name = "ipmi-powernv",
311 .of_match_table = ipmi_powernv_match,
312 },
313 .probe = ipmi_powernv_probe,
314 .remove = ipmi_powernv_remove,
315 };
316
317
318 module_platform_driver(powernv_ipmi_driver);
319
320 MODULE_DEVICE_TABLE(of, ipmi_powernv_match);
321 MODULE_DESCRIPTION("powernv IPMI driver");
322 MODULE_AUTHOR("Jeremy Kerr <jk@ozlabs.org>");
323 MODULE_LICENSE("GPL");
324