xref: /openbmc/linux/drivers/pci/endpoint/functions/pci-epf-test.c (revision ca90578000afb0d8f177ea36f7259a9c3640cf49)
1 // SPDX-License-Identifier: GPL-2.0
2 /**
3  * Test driver to test endpoint functionality
4  *
5  * Copyright (C) 2017 Texas Instruments
6  * Author: Kishon Vijay Abraham I <kishon@ti.com>
7  */
8 
9 #include <linux/crc32.h>
10 #include <linux/delay.h>
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/slab.h>
14 #include <linux/pci_ids.h>
15 #include <linux/random.h>
16 
17 #include <linux/pci-epc.h>
18 #include <linux/pci-epf.h>
19 #include <linux/pci_regs.h>
20 
21 #define COMMAND_RAISE_LEGACY_IRQ	BIT(0)
22 #define COMMAND_RAISE_MSI_IRQ		BIT(1)
23 #define MSI_NUMBER_SHIFT		2
24 #define MSI_NUMBER_MASK			(0x3f << MSI_NUMBER_SHIFT)
25 #define COMMAND_READ			BIT(8)
26 #define COMMAND_WRITE			BIT(9)
27 #define COMMAND_COPY			BIT(10)
28 
29 #define STATUS_READ_SUCCESS		BIT(0)
30 #define STATUS_READ_FAIL		BIT(1)
31 #define STATUS_WRITE_SUCCESS		BIT(2)
32 #define STATUS_WRITE_FAIL		BIT(3)
33 #define STATUS_COPY_SUCCESS		BIT(4)
34 #define STATUS_COPY_FAIL		BIT(5)
35 #define STATUS_IRQ_RAISED		BIT(6)
36 #define STATUS_SRC_ADDR_INVALID		BIT(7)
37 #define STATUS_DST_ADDR_INVALID		BIT(8)
38 
39 #define TIMER_RESOLUTION		1
40 
41 static struct workqueue_struct *kpcitest_workqueue;
42 
43 struct pci_epf_test {
44 	void			*reg[6];
45 	struct pci_epf		*epf;
46 	enum pci_barno		test_reg_bar;
47 	bool			linkup_notifier;
48 	struct delayed_work	cmd_handler;
49 };
50 
51 struct pci_epf_test_reg {
52 	u32	magic;
53 	u32	command;
54 	u32	status;
55 	u64	src_addr;
56 	u64	dst_addr;
57 	u32	size;
58 	u32	checksum;
59 } __packed;
60 
61 static struct pci_epf_header test_header = {
62 	.vendorid	= PCI_ANY_ID,
63 	.deviceid	= PCI_ANY_ID,
64 	.baseclass_code = PCI_CLASS_OTHERS,
65 	.interrupt_pin	= PCI_INTERRUPT_INTA,
66 };
67 
68 struct pci_epf_test_data {
69 	enum pci_barno	test_reg_bar;
70 	bool		linkup_notifier;
71 };
72 
73 static size_t bar_size[] = { 512, 512, 1024, 16384, 131072, 1048576 };
74 
75 static int pci_epf_test_copy(struct pci_epf_test *epf_test)
76 {
77 	int ret;
78 	void __iomem *src_addr;
79 	void __iomem *dst_addr;
80 	phys_addr_t src_phys_addr;
81 	phys_addr_t dst_phys_addr;
82 	struct pci_epf *epf = epf_test->epf;
83 	struct device *dev = &epf->dev;
84 	struct pci_epc *epc = epf->epc;
85 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
86 	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
87 
88 	src_addr = pci_epc_mem_alloc_addr(epc, &src_phys_addr, reg->size);
89 	if (!src_addr) {
90 		dev_err(dev, "failed to allocate source address\n");
91 		reg->status = STATUS_SRC_ADDR_INVALID;
92 		ret = -ENOMEM;
93 		goto err;
94 	}
95 
96 	ret = pci_epc_map_addr(epc, epf->func_no, src_phys_addr, reg->src_addr,
97 			       reg->size);
98 	if (ret) {
99 		dev_err(dev, "failed to map source address\n");
100 		reg->status = STATUS_SRC_ADDR_INVALID;
101 		goto err_src_addr;
102 	}
103 
104 	dst_addr = pci_epc_mem_alloc_addr(epc, &dst_phys_addr, reg->size);
105 	if (!dst_addr) {
106 		dev_err(dev, "failed to allocate destination address\n");
107 		reg->status = STATUS_DST_ADDR_INVALID;
108 		ret = -ENOMEM;
109 		goto err_src_map_addr;
110 	}
111 
112 	ret = pci_epc_map_addr(epc, epf->func_no, dst_phys_addr, reg->dst_addr,
113 			       reg->size);
114 	if (ret) {
115 		dev_err(dev, "failed to map destination address\n");
116 		reg->status = STATUS_DST_ADDR_INVALID;
117 		goto err_dst_addr;
118 	}
119 
120 	memcpy(dst_addr, src_addr, reg->size);
121 
122 	pci_epc_unmap_addr(epc, epf->func_no, dst_phys_addr);
123 
124 err_dst_addr:
125 	pci_epc_mem_free_addr(epc, dst_phys_addr, dst_addr, reg->size);
126 
127 err_src_map_addr:
128 	pci_epc_unmap_addr(epc, epf->func_no, src_phys_addr);
129 
130 err_src_addr:
131 	pci_epc_mem_free_addr(epc, src_phys_addr, src_addr, reg->size);
132 
133 err:
134 	return ret;
135 }
136 
137 static int pci_epf_test_read(struct pci_epf_test *epf_test)
138 {
139 	int ret;
140 	void __iomem *src_addr;
141 	void *buf;
142 	u32 crc32;
143 	phys_addr_t phys_addr;
144 	struct pci_epf *epf = epf_test->epf;
145 	struct device *dev = &epf->dev;
146 	struct pci_epc *epc = epf->epc;
147 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
148 	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
149 
150 	src_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
151 	if (!src_addr) {
152 		dev_err(dev, "failed to allocate address\n");
153 		reg->status = STATUS_SRC_ADDR_INVALID;
154 		ret = -ENOMEM;
155 		goto err;
156 	}
157 
158 	ret = pci_epc_map_addr(epc, epf->func_no, phys_addr, reg->src_addr,
159 			       reg->size);
160 	if (ret) {
161 		dev_err(dev, "failed to map address\n");
162 		reg->status = STATUS_SRC_ADDR_INVALID;
163 		goto err_addr;
164 	}
165 
166 	buf = kzalloc(reg->size, GFP_KERNEL);
167 	if (!buf) {
168 		ret = -ENOMEM;
169 		goto err_map_addr;
170 	}
171 
172 	memcpy(buf, src_addr, reg->size);
173 
174 	crc32 = crc32_le(~0, buf, reg->size);
175 	if (crc32 != reg->checksum)
176 		ret = -EIO;
177 
178 	kfree(buf);
179 
180 err_map_addr:
181 	pci_epc_unmap_addr(epc, epf->func_no, phys_addr);
182 
183 err_addr:
184 	pci_epc_mem_free_addr(epc, phys_addr, src_addr, reg->size);
185 
186 err:
187 	return ret;
188 }
189 
190 static int pci_epf_test_write(struct pci_epf_test *epf_test)
191 {
192 	int ret;
193 	void __iomem *dst_addr;
194 	void *buf;
195 	phys_addr_t phys_addr;
196 	struct pci_epf *epf = epf_test->epf;
197 	struct device *dev = &epf->dev;
198 	struct pci_epc *epc = epf->epc;
199 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
200 	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
201 
202 	dst_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
203 	if (!dst_addr) {
204 		dev_err(dev, "failed to allocate address\n");
205 		reg->status = STATUS_DST_ADDR_INVALID;
206 		ret = -ENOMEM;
207 		goto err;
208 	}
209 
210 	ret = pci_epc_map_addr(epc, epf->func_no, phys_addr, reg->dst_addr,
211 			       reg->size);
212 	if (ret) {
213 		dev_err(dev, "failed to map address\n");
214 		reg->status = STATUS_DST_ADDR_INVALID;
215 		goto err_addr;
216 	}
217 
218 	buf = kzalloc(reg->size, GFP_KERNEL);
219 	if (!buf) {
220 		ret = -ENOMEM;
221 		goto err_map_addr;
222 	}
223 
224 	get_random_bytes(buf, reg->size);
225 	reg->checksum = crc32_le(~0, buf, reg->size);
226 
227 	memcpy(dst_addr, buf, reg->size);
228 
229 	/*
230 	 * wait 1ms inorder for the write to complete. Without this delay L3
231 	 * error in observed in the host system.
232 	 */
233 	mdelay(1);
234 
235 	kfree(buf);
236 
237 err_map_addr:
238 	pci_epc_unmap_addr(epc, epf->func_no, phys_addr);
239 
240 err_addr:
241 	pci_epc_mem_free_addr(epc, phys_addr, dst_addr, reg->size);
242 
243 err:
244 	return ret;
245 }
246 
247 static void pci_epf_test_raise_irq(struct pci_epf_test *epf_test, u8 irq)
248 {
249 	u8 msi_count;
250 	struct pci_epf *epf = epf_test->epf;
251 	struct pci_epc *epc = epf->epc;
252 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
253 	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
254 
255 	reg->status |= STATUS_IRQ_RAISED;
256 	msi_count = pci_epc_get_msi(epc, epf->func_no);
257 	if (irq > msi_count || msi_count <= 0)
258 		pci_epc_raise_irq(epc, epf->func_no, PCI_EPC_IRQ_LEGACY, 0);
259 	else
260 		pci_epc_raise_irq(epc, epf->func_no, PCI_EPC_IRQ_MSI, irq);
261 }
262 
263 static void pci_epf_test_cmd_handler(struct work_struct *work)
264 {
265 	int ret;
266 	u8 irq;
267 	u8 msi_count;
268 	u32 command;
269 	struct pci_epf_test *epf_test = container_of(work, struct pci_epf_test,
270 						     cmd_handler.work);
271 	struct pci_epf *epf = epf_test->epf;
272 	struct pci_epc *epc = epf->epc;
273 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
274 	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
275 
276 	command = reg->command;
277 	if (!command)
278 		goto reset_handler;
279 
280 	reg->command = 0;
281 	reg->status = 0;
282 
283 	irq = (command & MSI_NUMBER_MASK) >> MSI_NUMBER_SHIFT;
284 
285 	if (command & COMMAND_RAISE_LEGACY_IRQ) {
286 		reg->status = STATUS_IRQ_RAISED;
287 		pci_epc_raise_irq(epc, epf->func_no, PCI_EPC_IRQ_LEGACY, 0);
288 		goto reset_handler;
289 	}
290 
291 	if (command & COMMAND_WRITE) {
292 		ret = pci_epf_test_write(epf_test);
293 		if (ret)
294 			reg->status |= STATUS_WRITE_FAIL;
295 		else
296 			reg->status |= STATUS_WRITE_SUCCESS;
297 		pci_epf_test_raise_irq(epf_test, irq);
298 		goto reset_handler;
299 	}
300 
301 	if (command & COMMAND_READ) {
302 		ret = pci_epf_test_read(epf_test);
303 		if (!ret)
304 			reg->status |= STATUS_READ_SUCCESS;
305 		else
306 			reg->status |= STATUS_READ_FAIL;
307 		pci_epf_test_raise_irq(epf_test, irq);
308 		goto reset_handler;
309 	}
310 
311 	if (command & COMMAND_COPY) {
312 		ret = pci_epf_test_copy(epf_test);
313 		if (!ret)
314 			reg->status |= STATUS_COPY_SUCCESS;
315 		else
316 			reg->status |= STATUS_COPY_FAIL;
317 		pci_epf_test_raise_irq(epf_test, irq);
318 		goto reset_handler;
319 	}
320 
321 	if (command & COMMAND_RAISE_MSI_IRQ) {
322 		msi_count = pci_epc_get_msi(epc, epf->func_no);
323 		if (irq > msi_count || msi_count <= 0)
324 			goto reset_handler;
325 		reg->status = STATUS_IRQ_RAISED;
326 		pci_epc_raise_irq(epc, epf->func_no, PCI_EPC_IRQ_MSI, irq);
327 		goto reset_handler;
328 	}
329 
330 reset_handler:
331 	queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
332 			   msecs_to_jiffies(1));
333 }
334 
335 static void pci_epf_test_linkup(struct pci_epf *epf)
336 {
337 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
338 
339 	queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
340 			   msecs_to_jiffies(1));
341 }
342 
343 static void pci_epf_test_unbind(struct pci_epf *epf)
344 {
345 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
346 	struct pci_epc *epc = epf->epc;
347 	struct pci_epf_bar *epf_bar;
348 	int bar;
349 
350 	cancel_delayed_work(&epf_test->cmd_handler);
351 	pci_epc_stop(epc);
352 	for (bar = BAR_0; bar <= BAR_5; bar++) {
353 		epf_bar = &epf->bar[bar];
354 
355 		if (epf_test->reg[bar]) {
356 			pci_epf_free_space(epf, epf_test->reg[bar], bar);
357 			pci_epc_clear_bar(epc, epf->func_no, epf_bar);
358 		}
359 	}
360 }
361 
362 static int pci_epf_test_set_bar(struct pci_epf *epf)
363 {
364 	int bar;
365 	int ret;
366 	struct pci_epf_bar *epf_bar;
367 	struct pci_epc *epc = epf->epc;
368 	struct device *dev = &epf->dev;
369 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
370 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
371 
372 	for (bar = BAR_0; bar <= BAR_5; bar++) {
373 		epf_bar = &epf->bar[bar];
374 
375 		epf_bar->flags |= upper_32_bits(epf_bar->size) ?
376 			PCI_BASE_ADDRESS_MEM_TYPE_64 :
377 			PCI_BASE_ADDRESS_MEM_TYPE_32;
378 
379 		ret = pci_epc_set_bar(epc, epf->func_no, epf_bar);
380 		if (ret) {
381 			pci_epf_free_space(epf, epf_test->reg[bar], bar);
382 			dev_err(dev, "failed to set BAR%d\n", bar);
383 			if (bar == test_reg_bar)
384 				return ret;
385 		}
386 		/*
387 		 * pci_epc_set_bar() sets PCI_BASE_ADDRESS_MEM_TYPE_64
388 		 * if the specific implementation required a 64-bit BAR,
389 		 * even if we only requested a 32-bit BAR.
390 		 */
391 		if (epf_bar->flags & PCI_BASE_ADDRESS_MEM_TYPE_64)
392 			bar++;
393 	}
394 
395 	return 0;
396 }
397 
398 static int pci_epf_test_alloc_space(struct pci_epf *epf)
399 {
400 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
401 	struct device *dev = &epf->dev;
402 	void *base;
403 	int bar;
404 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
405 
406 	base = pci_epf_alloc_space(epf, sizeof(struct pci_epf_test_reg),
407 				   test_reg_bar);
408 	if (!base) {
409 		dev_err(dev, "failed to allocated register space\n");
410 		return -ENOMEM;
411 	}
412 	epf_test->reg[test_reg_bar] = base;
413 
414 	for (bar = BAR_0; bar <= BAR_5; bar++) {
415 		if (bar == test_reg_bar)
416 			continue;
417 		base = pci_epf_alloc_space(epf, bar_size[bar], bar);
418 		if (!base)
419 			dev_err(dev, "failed to allocate space for BAR%d\n",
420 				bar);
421 		epf_test->reg[bar] = base;
422 	}
423 
424 	return 0;
425 }
426 
427 static int pci_epf_test_bind(struct pci_epf *epf)
428 {
429 	int ret;
430 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
431 	struct pci_epf_header *header = epf->header;
432 	struct pci_epc *epc = epf->epc;
433 	struct device *dev = &epf->dev;
434 
435 	if (WARN_ON_ONCE(!epc))
436 		return -EINVAL;
437 
438 	ret = pci_epc_write_header(epc, epf->func_no, header);
439 	if (ret) {
440 		dev_err(dev, "configuration header write failed\n");
441 		return ret;
442 	}
443 
444 	ret = pci_epf_test_alloc_space(epf);
445 	if (ret)
446 		return ret;
447 
448 	ret = pci_epf_test_set_bar(epf);
449 	if (ret)
450 		return ret;
451 
452 	ret = pci_epc_set_msi(epc, epf->func_no, epf->msi_interrupts);
453 	if (ret)
454 		return ret;
455 
456 	if (!epf_test->linkup_notifier)
457 		queue_work(kpcitest_workqueue, &epf_test->cmd_handler.work);
458 
459 	return 0;
460 }
461 
462 static const struct pci_epf_device_id pci_epf_test_ids[] = {
463 	{
464 		.name = "pci_epf_test",
465 	},
466 	{},
467 };
468 
469 static int pci_epf_test_probe(struct pci_epf *epf)
470 {
471 	struct pci_epf_test *epf_test;
472 	struct device *dev = &epf->dev;
473 	const struct pci_epf_device_id *match;
474 	struct pci_epf_test_data *data;
475 	enum pci_barno test_reg_bar = BAR_0;
476 	bool linkup_notifier = true;
477 
478 	match = pci_epf_match_device(pci_epf_test_ids, epf);
479 	data = (struct pci_epf_test_data *)match->driver_data;
480 	if (data) {
481 		test_reg_bar = data->test_reg_bar;
482 		linkup_notifier = data->linkup_notifier;
483 	}
484 
485 	epf_test = devm_kzalloc(dev, sizeof(*epf_test), GFP_KERNEL);
486 	if (!epf_test)
487 		return -ENOMEM;
488 
489 	epf->header = &test_header;
490 	epf_test->epf = epf;
491 	epf_test->test_reg_bar = test_reg_bar;
492 	epf_test->linkup_notifier = linkup_notifier;
493 
494 	INIT_DELAYED_WORK(&epf_test->cmd_handler, pci_epf_test_cmd_handler);
495 
496 	epf_set_drvdata(epf, epf_test);
497 	return 0;
498 }
499 
500 static struct pci_epf_ops ops = {
501 	.unbind	= pci_epf_test_unbind,
502 	.bind	= pci_epf_test_bind,
503 	.linkup = pci_epf_test_linkup,
504 };
505 
506 static struct pci_epf_driver test_driver = {
507 	.driver.name	= "pci_epf_test",
508 	.probe		= pci_epf_test_probe,
509 	.id_table	= pci_epf_test_ids,
510 	.ops		= &ops,
511 	.owner		= THIS_MODULE,
512 };
513 
514 static int __init pci_epf_test_init(void)
515 {
516 	int ret;
517 
518 	kpcitest_workqueue = alloc_workqueue("kpcitest",
519 					     WQ_MEM_RECLAIM | WQ_HIGHPRI, 0);
520 	ret = pci_epf_register_driver(&test_driver);
521 	if (ret) {
522 		pr_err("failed to register pci epf test driver --> %d\n", ret);
523 		return ret;
524 	}
525 
526 	return 0;
527 }
528 module_init(pci_epf_test_init);
529 
530 static void __exit pci_epf_test_exit(void)
531 {
532 	pci_epf_unregister_driver(&test_driver);
533 }
534 module_exit(pci_epf_test_exit);
535 
536 MODULE_DESCRIPTION("PCI EPF TEST DRIVER");
537 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
538 MODULE_LICENSE("GPL v2");
539