xref: /openbmc/linux/drivers/crypto/ccp/sp-dev.c (revision 884caada)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * AMD Secure Processor driver
4  *
5  * Copyright (C) 2017-2018 Advanced Micro Devices, Inc.
6  *
7  * Author: Tom Lendacky <thomas.lendacky@amd.com>
8  * Author: Gary R Hook <gary.hook@amd.com>
9  * Author: Brijesh Singh <brijesh.singh@amd.com>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/kthread.h>
15 #include <linux/sched.h>
16 #include <linux/interrupt.h>
17 #include <linux/spinlock.h>
18 #include <linux/spinlock_types.h>
19 #include <linux/types.h>
20 #include <linux/ccp.h>
21 
22 #include "ccp-dev.h"
23 #include "sp-dev.h"
24 
25 MODULE_AUTHOR("Tom Lendacky <thomas.lendacky@amd.com>");
26 MODULE_AUTHOR("Gary R Hook <gary.hook@amd.com>");
27 MODULE_LICENSE("GPL");
28 MODULE_VERSION("1.1.0");
29 MODULE_DESCRIPTION("AMD Secure Processor driver");
30 
31 /* List of SPs, SP count, read-write access lock, and access functions
32  *
33  * Lock structure: get sp_unit_lock for reading whenever we need to
34  * examine the SP list.
35  */
36 static DEFINE_RWLOCK(sp_unit_lock);
37 static LIST_HEAD(sp_units);
38 
39 /* Ever-increasing value to produce unique unit numbers */
40 static atomic_t sp_ordinal;
41 
42 static void sp_add_device(struct sp_device *sp)
43 {
44 	unsigned long flags;
45 
46 	write_lock_irqsave(&sp_unit_lock, flags);
47 
48 	list_add_tail(&sp->entry, &sp_units);
49 
50 	write_unlock_irqrestore(&sp_unit_lock, flags);
51 }
52 
53 static void sp_del_device(struct sp_device *sp)
54 {
55 	unsigned long flags;
56 
57 	write_lock_irqsave(&sp_unit_lock, flags);
58 
59 	list_del(&sp->entry);
60 
61 	write_unlock_irqrestore(&sp_unit_lock, flags);
62 }
63 
64 static irqreturn_t sp_irq_handler(int irq, void *data)
65 {
66 	struct sp_device *sp = data;
67 
68 	if (sp->ccp_irq_handler)
69 		sp->ccp_irq_handler(irq, sp->ccp_irq_data);
70 
71 	if (sp->psp_irq_handler)
72 		sp->psp_irq_handler(irq, sp->psp_irq_data);
73 
74 	return IRQ_HANDLED;
75 }
76 
77 int sp_request_ccp_irq(struct sp_device *sp, irq_handler_t handler,
78 		       const char *name, void *data)
79 {
80 	int ret;
81 
82 	if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->psp_vdata) {
83 		/* Need a common routine to manage all interrupts */
84 		sp->ccp_irq_data = data;
85 		sp->ccp_irq_handler = handler;
86 
87 		if (!sp->irq_registered) {
88 			ret = request_irq(sp->ccp_irq, sp_irq_handler, 0,
89 					  sp->name, sp);
90 			if (ret)
91 				return ret;
92 
93 			sp->irq_registered = true;
94 		}
95 	} else {
96 		/* Each sub-device can manage it's own interrupt */
97 		ret = request_irq(sp->ccp_irq, handler, 0, name, data);
98 		if (ret)
99 			return ret;
100 	}
101 
102 	return 0;
103 }
104 
105 int sp_request_psp_irq(struct sp_device *sp, irq_handler_t handler,
106 		       const char *name, void *data)
107 {
108 	int ret;
109 
110 	if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->ccp_vdata) {
111 		/* Need a common routine to manage all interrupts */
112 		sp->psp_irq_data = data;
113 		sp->psp_irq_handler = handler;
114 
115 		if (!sp->irq_registered) {
116 			ret = request_irq(sp->psp_irq, sp_irq_handler, 0,
117 					  sp->name, sp);
118 			if (ret)
119 				return ret;
120 
121 			sp->irq_registered = true;
122 		}
123 	} else {
124 		/* Each sub-device can manage it's own interrupt */
125 		ret = request_irq(sp->psp_irq, handler, 0, name, data);
126 		if (ret)
127 			return ret;
128 	}
129 
130 	return 0;
131 }
132 
133 void sp_free_ccp_irq(struct sp_device *sp, void *data)
134 {
135 	if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->psp_vdata) {
136 		/* Using common routine to manage all interrupts */
137 		if (!sp->psp_irq_handler) {
138 			/* Nothing else using it, so free it */
139 			free_irq(sp->ccp_irq, sp);
140 
141 			sp->irq_registered = false;
142 		}
143 
144 		sp->ccp_irq_handler = NULL;
145 		sp->ccp_irq_data = NULL;
146 	} else {
147 		/* Each sub-device can manage it's own interrupt */
148 		free_irq(sp->ccp_irq, data);
149 	}
150 }
151 
152 void sp_free_psp_irq(struct sp_device *sp, void *data)
153 {
154 	if ((sp->psp_irq == sp->ccp_irq) && sp->dev_vdata->ccp_vdata) {
155 		/* Using common routine to manage all interrupts */
156 		if (!sp->ccp_irq_handler) {
157 			/* Nothing else using it, so free it */
158 			free_irq(sp->psp_irq, sp);
159 
160 			sp->irq_registered = false;
161 		}
162 
163 		sp->psp_irq_handler = NULL;
164 		sp->psp_irq_data = NULL;
165 	} else {
166 		/* Each sub-device can manage it's own interrupt */
167 		free_irq(sp->psp_irq, data);
168 	}
169 }
170 
171 /**
172  * sp_alloc_struct - allocate and initialize the sp_device struct
173  *
174  * @dev: device struct of the SP
175  */
176 struct sp_device *sp_alloc_struct(struct device *dev)
177 {
178 	struct sp_device *sp;
179 
180 	sp = devm_kzalloc(dev, sizeof(*sp), GFP_KERNEL);
181 	if (!sp)
182 		return NULL;
183 
184 	sp->dev = dev;
185 	sp->ord = atomic_inc_return(&sp_ordinal);
186 	snprintf(sp->name, SP_MAX_NAME_LEN, "sp-%u", sp->ord);
187 
188 	return sp;
189 }
190 
191 int sp_init(struct sp_device *sp)
192 {
193 	sp_add_device(sp);
194 
195 	if (sp->dev_vdata->ccp_vdata)
196 		ccp_dev_init(sp);
197 
198 	if (sp->dev_vdata->psp_vdata)
199 		psp_dev_init(sp);
200 	return 0;
201 }
202 
203 void sp_destroy(struct sp_device *sp)
204 {
205 	if (sp->dev_vdata->ccp_vdata)
206 		ccp_dev_destroy(sp);
207 
208 	if (sp->dev_vdata->psp_vdata)
209 		psp_dev_destroy(sp);
210 
211 	sp_del_device(sp);
212 }
213 
214 #ifdef CONFIG_PM
215 int sp_suspend(struct sp_device *sp, pm_message_t state)
216 {
217 	int ret;
218 
219 	if (sp->dev_vdata->ccp_vdata) {
220 		ret = ccp_dev_suspend(sp, state);
221 		if (ret)
222 			return ret;
223 	}
224 
225 	return 0;
226 }
227 
228 int sp_resume(struct sp_device *sp)
229 {
230 	int ret;
231 
232 	if (sp->dev_vdata->ccp_vdata) {
233 		ret = ccp_dev_resume(sp);
234 		if (ret)
235 			return ret;
236 	}
237 
238 	return 0;
239 }
240 #endif
241 
242 struct sp_device *sp_get_psp_master_device(void)
243 {
244 	struct sp_device *i, *ret = NULL;
245 	unsigned long flags;
246 
247 	write_lock_irqsave(&sp_unit_lock, flags);
248 	if (list_empty(&sp_units))
249 		goto unlock;
250 
251 	list_for_each_entry(i, &sp_units, entry) {
252 		if (i->psp_data && i->get_psp_master_device) {
253 			ret = i->get_psp_master_device();
254 			break;
255 		}
256 	}
257 
258 unlock:
259 	write_unlock_irqrestore(&sp_unit_lock, flags);
260 	return ret;
261 }
262 
263 static int __init sp_mod_init(void)
264 {
265 #ifdef CONFIG_X86
266 	int ret;
267 
268 	ret = sp_pci_init();
269 	if (ret)
270 		return ret;
271 
272 #ifdef CONFIG_CRYPTO_DEV_SP_PSP
273 	psp_pci_init();
274 #endif
275 
276 	return 0;
277 #endif
278 
279 #ifdef CONFIG_ARM64
280 	int ret;
281 
282 	ret = sp_platform_init();
283 	if (ret)
284 		return ret;
285 
286 	return 0;
287 #endif
288 
289 	return -ENODEV;
290 }
291 
292 static void __exit sp_mod_exit(void)
293 {
294 #ifdef CONFIG_X86
295 
296 #ifdef CONFIG_CRYPTO_DEV_SP_PSP
297 	psp_pci_exit();
298 #endif
299 
300 	sp_pci_exit();
301 #endif
302 
303 #ifdef CONFIG_ARM64
304 	sp_platform_exit();
305 #endif
306 }
307 
308 module_init(sp_mod_init);
309 module_exit(sp_mod_exit);
310