1 /*
2 * AMD Cryptographic Coprocessor (CCP) driver
3 *
4 * Copyright (C) 2014 Advanced Micro Devices, Inc.
5 *
6 * Author: Tom Lendacky <thomas.lendacky@amd.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/device.h>
16 #include <linux/platform_device.h>
17 #include <linux/ioport.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/kthread.h>
20 #include <linux/sched.h>
21 #include <linux/interrupt.h>
22 #include <linux/spinlock.h>
23 #include <linux/delay.h>
24 #include <linux/ccp.h>
25 #include <linux/of.h>
26 #include <linux/of_address.h>
27 #include <linux/acpi.h>
28
29 #include "ccp-dev.h"
30
31 struct ccp_platform {
32 int coherent;
33 };
34
ccp_get_irq(struct ccp_device * ccp)35 static int ccp_get_irq(struct ccp_device *ccp)
36 {
37 struct device *dev = ccp->dev;
38 struct platform_device *pdev = container_of(dev,
39 struct platform_device, dev);
40 int ret;
41
42 ret = platform_get_irq(pdev, 0);
43 if (ret < 0)
44 return ret;
45
46 ccp->irq = ret;
47 ret = request_irq(ccp->irq, ccp_irq_handler, 0, "ccp", dev);
48 if (ret) {
49 dev_notice(dev, "unable to allocate IRQ (%d)\n", ret);
50 return ret;
51 }
52
53 return 0;
54 }
55
ccp_get_irqs(struct ccp_device * ccp)56 static int ccp_get_irqs(struct ccp_device *ccp)
57 {
58 struct device *dev = ccp->dev;
59 int ret;
60
61 ret = ccp_get_irq(ccp);
62 if (!ret)
63 return 0;
64
65 /* Couldn't get an interrupt */
66 dev_notice(dev, "could not enable interrupts (%d)\n", ret);
67
68 return ret;
69 }
70
ccp_free_irqs(struct ccp_device * ccp)71 static void ccp_free_irqs(struct ccp_device *ccp)
72 {
73 struct device *dev = ccp->dev;
74
75 free_irq(ccp->irq, dev);
76 }
77
ccp_find_mmio_area(struct ccp_device * ccp)78 static struct resource *ccp_find_mmio_area(struct ccp_device *ccp)
79 {
80 struct device *dev = ccp->dev;
81 struct platform_device *pdev = container_of(dev,
82 struct platform_device, dev);
83 struct resource *ior;
84
85 ior = platform_get_resource(pdev, IORESOURCE_MEM, 0);
86 if (ior && (resource_size(ior) >= 0x800))
87 return ior;
88
89 return NULL;
90 }
91
ccp_platform_probe(struct platform_device * pdev)92 static int ccp_platform_probe(struct platform_device *pdev)
93 {
94 struct ccp_device *ccp;
95 struct ccp_platform *ccp_platform;
96 struct device *dev = &pdev->dev;
97 enum dev_dma_attr attr;
98 struct resource *ior;
99 int ret;
100
101 ret = -ENOMEM;
102 ccp = ccp_alloc_struct(dev);
103 if (!ccp)
104 goto e_err;
105
106 ccp_platform = devm_kzalloc(dev, sizeof(*ccp_platform), GFP_KERNEL);
107 if (!ccp_platform)
108 goto e_err;
109
110 ccp->dev_specific = ccp_platform;
111 ccp->get_irq = ccp_get_irqs;
112 ccp->free_irq = ccp_free_irqs;
113
114 ior = ccp_find_mmio_area(ccp);
115 ccp->io_map = devm_ioremap_resource(dev, ior);
116 if (IS_ERR(ccp->io_map)) {
117 ret = PTR_ERR(ccp->io_map);
118 goto e_err;
119 }
120 ccp->io_regs = ccp->io_map;
121
122 attr = device_get_dma_attr(dev);
123 if (attr == DEV_DMA_NOT_SUPPORTED) {
124 dev_err(dev, "DMA is not supported");
125 goto e_err;
126 }
127
128 ccp_platform->coherent = (attr == DEV_DMA_COHERENT);
129 if (ccp_platform->coherent)
130 ccp->axcache = CACHE_WB_NO_ALLOC;
131 else
132 ccp->axcache = CACHE_NONE;
133
134 ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48));
135 if (ret) {
136 dev_err(dev, "dma_set_mask_and_coherent failed (%d)\n", ret);
137 goto e_err;
138 }
139
140 dev_set_drvdata(dev, ccp);
141
142 ret = ccp_init(ccp);
143 if (ret)
144 goto e_err;
145
146 dev_notice(dev, "enabled\n");
147
148 return 0;
149
150 e_err:
151 dev_notice(dev, "initialization failed\n");
152 return ret;
153 }
154
ccp_platform_remove(struct platform_device * pdev)155 static int ccp_platform_remove(struct platform_device *pdev)
156 {
157 struct device *dev = &pdev->dev;
158 struct ccp_device *ccp = dev_get_drvdata(dev);
159
160 ccp_destroy(ccp);
161
162 dev_notice(dev, "disabled\n");
163
164 return 0;
165 }
166
167 #ifdef CONFIG_PM
ccp_platform_suspend(struct platform_device * pdev,pm_message_t state)168 static int ccp_platform_suspend(struct platform_device *pdev,
169 pm_message_t state)
170 {
171 struct device *dev = &pdev->dev;
172 struct ccp_device *ccp = dev_get_drvdata(dev);
173 unsigned long flags;
174 unsigned int i;
175
176 spin_lock_irqsave(&ccp->cmd_lock, flags);
177
178 ccp->suspending = 1;
179
180 /* Wake all the queue kthreads to prepare for suspend */
181 for (i = 0; i < ccp->cmd_q_count; i++)
182 wake_up_process(ccp->cmd_q[i].kthread);
183
184 spin_unlock_irqrestore(&ccp->cmd_lock, flags);
185
186 /* Wait for all queue kthreads to say they're done */
187 while (!ccp_queues_suspended(ccp))
188 wait_event_interruptible(ccp->suspend_queue,
189 ccp_queues_suspended(ccp));
190
191 return 0;
192 }
193
ccp_platform_resume(struct platform_device * pdev)194 static int ccp_platform_resume(struct platform_device *pdev)
195 {
196 struct device *dev = &pdev->dev;
197 struct ccp_device *ccp = dev_get_drvdata(dev);
198 unsigned long flags;
199 unsigned int i;
200
201 spin_lock_irqsave(&ccp->cmd_lock, flags);
202
203 ccp->suspending = 0;
204
205 /* Wake up all the kthreads */
206 for (i = 0; i < ccp->cmd_q_count; i++) {
207 ccp->cmd_q[i].suspended = 0;
208 wake_up_process(ccp->cmd_q[i].kthread);
209 }
210
211 spin_unlock_irqrestore(&ccp->cmd_lock, flags);
212
213 return 0;
214 }
215 #endif
216
217 #ifdef CONFIG_ACPI
218 static const struct acpi_device_id ccp_acpi_match[] = {
219 { "AMDI0C00", 0 },
220 { },
221 };
222 MODULE_DEVICE_TABLE(acpi, ccp_acpi_match);
223 #endif
224
225 #ifdef CONFIG_OF
226 static const struct of_device_id ccp_of_match[] = {
227 { .compatible = "amd,ccp-seattle-v1a" },
228 { },
229 };
230 MODULE_DEVICE_TABLE(of, ccp_of_match);
231 #endif
232
233 static struct platform_driver ccp_platform_driver = {
234 .driver = {
235 .name = "ccp",
236 #ifdef CONFIG_ACPI
237 .acpi_match_table = ccp_acpi_match,
238 #endif
239 #ifdef CONFIG_OF
240 .of_match_table = ccp_of_match,
241 #endif
242 },
243 .probe = ccp_platform_probe,
244 .remove = ccp_platform_remove,
245 #ifdef CONFIG_PM
246 .suspend = ccp_platform_suspend,
247 .resume = ccp_platform_resume,
248 #endif
249 };
250
ccp_platform_init(void)251 int ccp_platform_init(void)
252 {
253 return platform_driver_register(&ccp_platform_driver);
254 }
255
ccp_platform_exit(void)256 void ccp_platform_exit(void)
257 {
258 platform_driver_unregister(&ccp_platform_driver);
259 }
260