xref: /openbmc/linux/drivers/crypto/ccp/sp-dev.c (revision d2574c33)
1 /*
2  * AMD Secure Processor driver
3  *
4  * Copyright (C) 2017-2018 Advanced Micro Devices, Inc.
5  *
6  * Author: Tom Lendacky <thomas.lendacky@amd.com>
7  * Author: Gary R Hook <gary.hook@amd.com>
8  * Author: Brijesh Singh <brijesh.singh@amd.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License version 2 as
12  * published by the Free Software Foundation.
13  */
14 
15 #include <linux/module.h>
16 #include <linux/kernel.h>
17 #include <linux/kthread.h>
18 #include <linux/sched.h>
19 #include <linux/interrupt.h>
20 #include <linux/spinlock.h>
21 #include <linux/spinlock_types.h>
22 #include <linux/types.h>
23 #include <linux/ccp.h>
24 
25 #include "ccp-dev.h"
26 #include "sp-dev.h"
27 
28 MODULE_AUTHOR("Tom Lendacky <thomas.lendacky@amd.com>");
29 MODULE_AUTHOR("Gary R Hook <gary.hook@amd.com>");
30 MODULE_LICENSE("GPL");
31 MODULE_VERSION("1.1.0");
32 MODULE_DESCRIPTION("AMD Secure Processor driver");
33 
34 /* List of SPs, SP count, read-write access lock, and access functions
35  *
36  * Lock structure: get sp_unit_lock for reading whenever we need to
37  * examine the SP list.
38  */
39 static DEFINE_RWLOCK(sp_unit_lock);
40 static LIST_HEAD(sp_units);
41 
42 /* Ever-increasing value to produce unique unit numbers */
43 static atomic_t sp_ordinal;
44 
45 static void sp_add_device(struct sp_device *sp)
46 {
47 	unsigned long flags;
48 
49 	write_lock_irqsave(&sp_unit_lock, flags);
50 
51 	list_add_tail(&sp->entry, &sp_units);
52 
53 	write_unlock_irqrestore(&sp_unit_lock, flags);
54 }
55 
56 static void sp_del_device(struct sp_device *sp)
57 {
58 	unsigned long flags;
59 
60 	write_lock_irqsave(&sp_unit_lock, flags);
61 
62 	list_del(&sp->entry);
63 
64 	write_unlock_irqrestore(&sp_unit_lock, flags);
65 }
66 
67 static irqreturn_t sp_irq_handler(int irq, void *data)
68 {
69 	struct sp_device *sp = data;
70 
71 	if (sp->ccp_irq_handler)
72 		sp->ccp_irq_handler(irq, sp->ccp_irq_data);
73 
74 	if (sp->psp_irq_handler)
75 		sp->psp_irq_handler(irq, sp->psp_irq_data);
76 
77 	return IRQ_HANDLED;
78 }
79 
80 int sp_request_ccp_irq(struct sp_device *sp, irq_handler_t handler,
81 		       const char *name, void *data)
82 {
83 	int ret;
84 
85 	if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->psp_vdata) {
86 		/* Need a common routine to manage all interrupts */
87 		sp->ccp_irq_data = data;
88 		sp->ccp_irq_handler = handler;
89 
90 		if (!sp->irq_registered) {
91 			ret = request_irq(sp->ccp_irq, sp_irq_handler, 0,
92 					  sp->name, sp);
93 			if (ret)
94 				return ret;
95 
96 			sp->irq_registered = true;
97 		}
98 	} else {
99 		/* Each sub-device can manage it's own interrupt */
100 		ret = request_irq(sp->ccp_irq, handler, 0, name, data);
101 		if (ret)
102 			return ret;
103 	}
104 
105 	return 0;
106 }
107 
108 int sp_request_psp_irq(struct sp_device *sp, irq_handler_t handler,
109 		       const char *name, void *data)
110 {
111 	int ret;
112 
113 	if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->ccp_vdata) {
114 		/* Need a common routine to manage all interrupts */
115 		sp->psp_irq_data = data;
116 		sp->psp_irq_handler = handler;
117 
118 		if (!sp->irq_registered) {
119 			ret = request_irq(sp->psp_irq, sp_irq_handler, 0,
120 					  sp->name, sp);
121 			if (ret)
122 				return ret;
123 
124 			sp->irq_registered = true;
125 		}
126 	} else {
127 		/* Each sub-device can manage it's own interrupt */
128 		ret = request_irq(sp->psp_irq, handler, 0, name, data);
129 		if (ret)
130 			return ret;
131 	}
132 
133 	return 0;
134 }
135 
136 void sp_free_ccp_irq(struct sp_device *sp, void *data)
137 {
138 	if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->psp_vdata) {
139 		/* Using common routine to manage all interrupts */
140 		if (!sp->psp_irq_handler) {
141 			/* Nothing else using it, so free it */
142 			free_irq(sp->ccp_irq, sp);
143 
144 			sp->irq_registered = false;
145 		}
146 
147 		sp->ccp_irq_handler = NULL;
148 		sp->ccp_irq_data = NULL;
149 	} else {
150 		/* Each sub-device can manage it's own interrupt */
151 		free_irq(sp->ccp_irq, data);
152 	}
153 }
154 
155 void sp_free_psp_irq(struct sp_device *sp, void *data)
156 {
157 	if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->ccp_vdata) {
158 		/* Using common routine to manage all interrupts */
159 		if (!sp->ccp_irq_handler) {
160 			/* Nothing else using it, so free it */
161 			free_irq(sp->psp_irq, sp);
162 
163 			sp->irq_registered = false;
164 		}
165 
166 		sp->psp_irq_handler = NULL;
167 		sp->psp_irq_data = NULL;
168 	} else {
169 		/* Each sub-device can manage it's own interrupt */
170 		free_irq(sp->psp_irq, data);
171 	}
172 }
173 
174 /**
175  * sp_alloc_struct - allocate and initialize the sp_device struct
176  *
177  * @dev: device struct of the SP
178  */
179 struct sp_device *sp_alloc_struct(struct device *dev)
180 {
181 	struct sp_device *sp;
182 
183 	sp = devm_kzalloc(dev, sizeof(*sp), GFP_KERNEL);
184 	if (!sp)
185 		return NULL;
186 
187 	sp->dev = dev;
188 	sp->ord = atomic_inc_return(&sp_ordinal);
189 	snprintf(sp->name, SP_MAX_NAME_LEN, "sp-%u", sp->ord);
190 
191 	return sp;
192 }
193 
194 int sp_init(struct sp_device *sp)
195 {
196 	sp_add_device(sp);
197 
198 	if (sp->dev_vdata->ccp_vdata)
199 		ccp_dev_init(sp);
200 
201 	if (sp->dev_vdata->psp_vdata)
202 		psp_dev_init(sp);
203 	return 0;
204 }
205 
206 void sp_destroy(struct sp_device *sp)
207 {
208 	if (sp->dev_vdata->ccp_vdata)
209 		ccp_dev_destroy(sp);
210 
211 	if (sp->dev_vdata->psp_vdata)
212 		psp_dev_destroy(sp);
213 
214 	sp_del_device(sp);
215 }
216 
217 #ifdef CONFIG_PM
218 int sp_suspend(struct sp_device *sp, pm_message_t state)
219 {
220 	int ret;
221 
222 	if (sp->dev_vdata->ccp_vdata) {
223 		ret = ccp_dev_suspend(sp, state);
224 		if (ret)
225 			return ret;
226 	}
227 
228 	return 0;
229 }
230 
231 int sp_resume(struct sp_device *sp)
232 {
233 	int ret;
234 
235 	if (sp->dev_vdata->ccp_vdata) {
236 		ret = ccp_dev_resume(sp);
237 		if (ret)
238 			return ret;
239 	}
240 
241 	return 0;
242 }
243 #endif
244 
245 struct sp_device *sp_get_psp_master_device(void)
246 {
247 	struct sp_device *i, *ret = NULL;
248 	unsigned long flags;
249 
250 	write_lock_irqsave(&sp_unit_lock, flags);
251 	if (list_empty(&sp_units))
252 		goto unlock;
253 
254 	list_for_each_entry(i, &sp_units, entry) {
255 		if (i->psp_data && i->get_psp_master_device) {
256 			ret = i->get_psp_master_device();
257 			break;
258 		}
259 	}
260 
261 unlock:
262 	write_unlock_irqrestore(&sp_unit_lock, flags);
263 	return ret;
264 }
265 
266 static int __init sp_mod_init(void)
267 {
268 #ifdef CONFIG_X86
269 	int ret;
270 
271 	ret = sp_pci_init();
272 	if (ret)
273 		return ret;
274 
275 #ifdef CONFIG_CRYPTO_DEV_SP_PSP
276 	psp_pci_init();
277 #endif
278 
279 	return 0;
280 #endif
281 
282 #ifdef CONFIG_ARM64
283 	int ret;
284 
285 	ret = sp_platform_init();
286 	if (ret)
287 		return ret;
288 
289 	return 0;
290 #endif
291 
292 	return -ENODEV;
293 }
294 
295 static void __exit sp_mod_exit(void)
296 {
297 #ifdef CONFIG_X86
298 
299 #ifdef CONFIG_CRYPTO_DEV_SP_PSP
300 	psp_pci_exit();
301 #endif
302 
303 	sp_pci_exit();
304 #endif
305 
306 #ifdef CONFIG_ARM64
307 	sp_platform_exit();
308 #endif
309 }
310 
311 module_init(sp_mod_init);
312 module_exit(sp_mod_exit);
313