1/*
2 * AMD Cryptographic Coprocessor (CCP) driver
3 *
4 * Copyright (C) 2013 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/pci.h>
17#include <linux/pci_ids.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
26#include "ccp-dev.h"
27
28#define IO_BAR				2
29#define IO_OFFSET			0x20000
30
31#define MSIX_VECTORS			2
32
33struct ccp_msix {
34	u32 vector;
35	char name[16];
36};
37
38struct ccp_pci {
39	int msix_count;
40	struct ccp_msix msix[MSIX_VECTORS];
41};
42
43static int ccp_get_msix_irqs(struct ccp_device *ccp)
44{
45	struct ccp_pci *ccp_pci = ccp->dev_specific;
46	struct device *dev = ccp->dev;
47	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
48	struct msix_entry msix_entry[MSIX_VECTORS];
49	unsigned int name_len = sizeof(ccp_pci->msix[0].name) - 1;
50	int v, ret;
51
52	for (v = 0; v < ARRAY_SIZE(msix_entry); v++)
53		msix_entry[v].entry = v;
54
55	ret = pci_enable_msix_range(pdev, msix_entry, 1, v);
56	if (ret < 0)
57		return ret;
58
59	ccp_pci->msix_count = ret;
60	for (v = 0; v < ccp_pci->msix_count; v++) {
61		/* Set the interrupt names and request the irqs */
62		snprintf(ccp_pci->msix[v].name, name_len, "ccp-%u", v);
63		ccp_pci->msix[v].vector = msix_entry[v].vector;
64		ret = request_irq(ccp_pci->msix[v].vector, ccp_irq_handler,
65				  0, ccp_pci->msix[v].name, dev);
66		if (ret) {
67			dev_notice(dev, "unable to allocate MSI-X IRQ (%d)\n",
68				   ret);
69			goto e_irq;
70		}
71	}
72
73	return 0;
74
75e_irq:
76	while (v--)
77		free_irq(ccp_pci->msix[v].vector, dev);
78
79	pci_disable_msix(pdev);
80
81	ccp_pci->msix_count = 0;
82
83	return ret;
84}
85
86static int ccp_get_msi_irq(struct ccp_device *ccp)
87{
88	struct device *dev = ccp->dev;
89	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
90	int ret;
91
92	ret = pci_enable_msi(pdev);
93	if (ret)
94		return ret;
95
96	ccp->irq = pdev->irq;
97	ret = request_irq(ccp->irq, ccp_irq_handler, 0, "ccp", dev);
98	if (ret) {
99		dev_notice(dev, "unable to allocate MSI IRQ (%d)\n", ret);
100		goto e_msi;
101	}
102
103	return 0;
104
105e_msi:
106	pci_disable_msi(pdev);
107
108	return ret;
109}
110
111static int ccp_get_irqs(struct ccp_device *ccp)
112{
113	struct device *dev = ccp->dev;
114	int ret;
115
116	ret = ccp_get_msix_irqs(ccp);
117	if (!ret)
118		return 0;
119
120	/* Couldn't get MSI-X vectors, try MSI */
121	dev_notice(dev, "could not enable MSI-X (%d), trying MSI\n", ret);
122	ret = ccp_get_msi_irq(ccp);
123	if (!ret)
124		return 0;
125
126	/* Couldn't get MSI interrupt */
127	dev_notice(dev, "could not enable MSI (%d)\n", ret);
128
129	return ret;
130}
131
132static void ccp_free_irqs(struct ccp_device *ccp)
133{
134	struct ccp_pci *ccp_pci = ccp->dev_specific;
135	struct device *dev = ccp->dev;
136	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
137
138	if (ccp_pci->msix_count) {
139		while (ccp_pci->msix_count--)
140			free_irq(ccp_pci->msix[ccp_pci->msix_count].vector,
141				 dev);
142		pci_disable_msix(pdev);
143	} else {
144		free_irq(ccp->irq, dev);
145		pci_disable_msi(pdev);
146	}
147}
148
149static int ccp_find_mmio_area(struct ccp_device *ccp)
150{
151	struct device *dev = ccp->dev;
152	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
153	resource_size_t io_len;
154	unsigned long io_flags;
155
156	io_flags = pci_resource_flags(pdev, IO_BAR);
157	io_len = pci_resource_len(pdev, IO_BAR);
158	if ((io_flags & IORESOURCE_MEM) && (io_len >= (IO_OFFSET + 0x800)))
159		return IO_BAR;
160
161	return -EIO;
162}
163
164static int ccp_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
165{
166	struct ccp_device *ccp;
167	struct ccp_pci *ccp_pci;
168	struct device *dev = &pdev->dev;
169	unsigned int bar;
170	int ret;
171
172	ret = -ENOMEM;
173	ccp = ccp_alloc_struct(dev);
174	if (!ccp)
175		goto e_err;
176
177	ccp_pci = devm_kzalloc(dev, sizeof(*ccp_pci), GFP_KERNEL);
178	if (!ccp_pci)
179		goto e_err;
180
181	ccp->dev_specific = ccp_pci;
182	ccp->get_irq = ccp_get_irqs;
183	ccp->free_irq = ccp_free_irqs;
184
185	ret = pci_request_regions(pdev, "ccp");
186	if (ret) {
187		dev_err(dev, "pci_request_regions failed (%d)\n", ret);
188		goto e_err;
189	}
190
191	ret = pci_enable_device(pdev);
192	if (ret) {
193		dev_err(dev, "pci_enable_device failed (%d)\n", ret);
194		goto e_regions;
195	}
196
197	pci_set_master(pdev);
198
199	ret = ccp_find_mmio_area(ccp);
200	if (ret < 0)
201		goto e_device;
202	bar = ret;
203
204	ret = -EIO;
205	ccp->io_map = pci_iomap(pdev, bar, 0);
206	if (!ccp->io_map) {
207		dev_err(dev, "pci_iomap failed\n");
208		goto e_device;
209	}
210	ccp->io_regs = ccp->io_map + IO_OFFSET;
211
212	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48));
213	if (ret) {
214		ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32));
215		if (ret) {
216			dev_err(dev, "dma_set_mask_and_coherent failed (%d)\n",
217				ret);
218			goto e_iomap;
219		}
220	}
221
222	dev_set_drvdata(dev, ccp);
223
224	ret = ccp_init(ccp);
225	if (ret)
226		goto e_iomap;
227
228	dev_notice(dev, "enabled\n");
229
230	return 0;
231
232e_iomap:
233	pci_iounmap(pdev, ccp->io_map);
234
235e_device:
236	pci_disable_device(pdev);
237
238e_regions:
239	pci_release_regions(pdev);
240
241e_err:
242	dev_notice(dev, "initialization failed\n");
243	return ret;
244}
245
246static void ccp_pci_remove(struct pci_dev *pdev)
247{
248	struct device *dev = &pdev->dev;
249	struct ccp_device *ccp = dev_get_drvdata(dev);
250
251	if (!ccp)
252		return;
253
254	ccp_destroy(ccp);
255
256	pci_iounmap(pdev, ccp->io_map);
257
258	pci_disable_device(pdev);
259
260	pci_release_regions(pdev);
261
262	dev_notice(dev, "disabled\n");
263}
264
265#ifdef CONFIG_PM
266static int ccp_pci_suspend(struct pci_dev *pdev, pm_message_t state)
267{
268	struct device *dev = &pdev->dev;
269	struct ccp_device *ccp = dev_get_drvdata(dev);
270	unsigned long flags;
271	unsigned int i;
272
273	spin_lock_irqsave(&ccp->cmd_lock, flags);
274
275	ccp->suspending = 1;
276
277	/* Wake all the queue kthreads to prepare for suspend */
278	for (i = 0; i < ccp->cmd_q_count; i++)
279		wake_up_process(ccp->cmd_q[i].kthread);
280
281	spin_unlock_irqrestore(&ccp->cmd_lock, flags);
282
283	/* Wait for all queue kthreads to say they're done */
284	while (!ccp_queues_suspended(ccp))
285		wait_event_interruptible(ccp->suspend_queue,
286					 ccp_queues_suspended(ccp));
287
288	return 0;
289}
290
291static int ccp_pci_resume(struct pci_dev *pdev)
292{
293	struct device *dev = &pdev->dev;
294	struct ccp_device *ccp = dev_get_drvdata(dev);
295	unsigned long flags;
296	unsigned int i;
297
298	spin_lock_irqsave(&ccp->cmd_lock, flags);
299
300	ccp->suspending = 0;
301
302	/* Wake up all the kthreads */
303	for (i = 0; i < ccp->cmd_q_count; i++) {
304		ccp->cmd_q[i].suspended = 0;
305		wake_up_process(ccp->cmd_q[i].kthread);
306	}
307
308	spin_unlock_irqrestore(&ccp->cmd_lock, flags);
309
310	return 0;
311}
312#endif
313
314static const struct pci_device_id ccp_pci_table[] = {
315	{ PCI_VDEVICE(AMD, 0x1537), },
316	/* Last entry must be zero */
317	{ 0, }
318};
319MODULE_DEVICE_TABLE(pci, ccp_pci_table);
320
321static struct pci_driver ccp_pci_driver = {
322	.name = "ccp",
323	.id_table = ccp_pci_table,
324	.probe = ccp_pci_probe,
325	.remove = ccp_pci_remove,
326#ifdef CONFIG_PM
327	.suspend = ccp_pci_suspend,
328	.resume = ccp_pci_resume,
329#endif
330};
331
332int ccp_pci_init(void)
333{
334	return pci_register_driver(&ccp_pci_driver);
335}
336
337void ccp_pci_exit(void)
338{
339	pci_unregister_driver(&ccp_pci_driver);
340}
341