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(intf: 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(lock: &smi->msg_lock, flags); |
100 | return; |
101 | } |
102 | |
103 | comp = IPMI_ERR_UNSPECIFIED; |
104 | err_unlock: |
105 | spin_unlock_irqrestore(lock: &smi->msg_lock, flags); |
106 | err: |
107 | send_error_reply(smi, msg, completion_code: 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(lock: &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(lock: &smi->msg_lock, flags); |
144 | return 0; |
145 | } |
146 | |
147 | smi->cur_msg = NULL; |
148 | spin_unlock_irqrestore(lock: &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(lock: &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(lock: &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(lock: &smi->msg_lock, flags); |
174 | ipmi_smi_msg_received(intf: 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, size: 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(np: dev->of_node, propname: "ibm,ipmi-interface-id" , |
230 | out_value: &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(np: dev->of_node, propname: "interrupts" , out_value: &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(node: dev->of_node, index: 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(irq: ipmi->irq, handler: ipmi_opal_event, flags: IRQ_TYPE_LEVEL_HIGH, |
250 | name: "opal-ipmi" , dev: 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, data: ipmi); |
271 | return 0; |
272 | |
273 | err_free_msg: |
274 | devm_kfree(dev, p: ipmi->opal_msg); |
275 | err_unregister: |
276 | free_irq(ipmi->irq, ipmi); |
277 | err_dispose: |
278 | irq_dispose_mapping(virq: ipmi->irq); |
279 | err_free: |
280 | devm_kfree(dev, p: 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(dev: &pdev->dev); |
287 | |
288 | ipmi_unregister_smi(intf: smi->intf); |
289 | free_irq(smi->irq, smi); |
290 | irq_dispose_mapping(virq: 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 | |