xref: /linux/drivers/pci/endpoint/functions/pci-epf-test.c (revision ee8287e068a3995b0f8001dd6931e221dfb7c530)
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/dmaengine.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/pci_ids.h>
16 #include <linux/random.h>
17 
18 #include <linux/pci-epc.h>
19 #include <linux/pci-epf.h>
20 #include <linux/pci_regs.h>
21 
22 #define IRQ_TYPE_INTX			0
23 #define IRQ_TYPE_MSI			1
24 #define IRQ_TYPE_MSIX			2
25 
26 #define COMMAND_RAISE_INTX_IRQ		BIT(0)
27 #define COMMAND_RAISE_MSI_IRQ		BIT(1)
28 #define COMMAND_RAISE_MSIX_IRQ		BIT(2)
29 #define COMMAND_READ			BIT(3)
30 #define COMMAND_WRITE			BIT(4)
31 #define COMMAND_COPY			BIT(5)
32 
33 #define STATUS_READ_SUCCESS		BIT(0)
34 #define STATUS_READ_FAIL		BIT(1)
35 #define STATUS_WRITE_SUCCESS		BIT(2)
36 #define STATUS_WRITE_FAIL		BIT(3)
37 #define STATUS_COPY_SUCCESS		BIT(4)
38 #define STATUS_COPY_FAIL		BIT(5)
39 #define STATUS_IRQ_RAISED		BIT(6)
40 #define STATUS_SRC_ADDR_INVALID		BIT(7)
41 #define STATUS_DST_ADDR_INVALID		BIT(8)
42 
43 #define FLAG_USE_DMA			BIT(0)
44 
45 #define TIMER_RESOLUTION		1
46 
47 static struct workqueue_struct *kpcitest_workqueue;
48 
49 struct pci_epf_test {
50 	void			*reg[PCI_STD_NUM_BARS];
51 	struct pci_epf		*epf;
52 	enum pci_barno		test_reg_bar;
53 	size_t			msix_table_offset;
54 	struct delayed_work	cmd_handler;
55 	struct dma_chan		*dma_chan_tx;
56 	struct dma_chan		*dma_chan_rx;
57 	struct dma_chan		*transfer_chan;
58 	dma_cookie_t		transfer_cookie;
59 	enum dma_status		transfer_status;
60 	struct completion	transfer_complete;
61 	bool			dma_supported;
62 	bool			dma_private;
63 	const struct pci_epc_features *epc_features;
64 };
65 
66 struct pci_epf_test_reg {
67 	u32	magic;
68 	u32	command;
69 	u32	status;
70 	u64	src_addr;
71 	u64	dst_addr;
72 	u32	size;
73 	u32	checksum;
74 	u32	irq_type;
75 	u32	irq_number;
76 	u32	flags;
77 } __packed;
78 
79 static struct pci_epf_header test_header = {
80 	.vendorid	= PCI_ANY_ID,
81 	.deviceid	= PCI_ANY_ID,
82 	.baseclass_code = PCI_CLASS_OTHERS,
83 	.interrupt_pin	= PCI_INTERRUPT_INTA,
84 };
85 
86 static size_t bar_size[] = { 512, 512, 1024, 16384, 131072, 1048576 };
87 
88 static void pci_epf_test_dma_callback(void *param)
89 {
90 	struct pci_epf_test *epf_test = param;
91 	struct dma_tx_state state;
92 
93 	epf_test->transfer_status =
94 		dmaengine_tx_status(epf_test->transfer_chan,
95 				    epf_test->transfer_cookie, &state);
96 	if (epf_test->transfer_status == DMA_COMPLETE ||
97 	    epf_test->transfer_status == DMA_ERROR)
98 		complete(&epf_test->transfer_complete);
99 }
100 
101 /**
102  * pci_epf_test_data_transfer() - Function that uses dmaengine API to transfer
103  *				  data between PCIe EP and remote PCIe RC
104  * @epf_test: the EPF test device that performs the data transfer operation
105  * @dma_dst: The destination address of the data transfer. It can be a physical
106  *	     address given by pci_epc_mem_alloc_addr or DMA mapping APIs.
107  * @dma_src: The source address of the data transfer. It can be a physical
108  *	     address given by pci_epc_mem_alloc_addr or DMA mapping APIs.
109  * @len: The size of the data transfer
110  * @dma_remote: remote RC physical address
111  * @dir: DMA transfer direction
112  *
113  * Function that uses dmaengine API to transfer data between PCIe EP and remote
114  * PCIe RC. The source and destination address can be a physical address given
115  * by pci_epc_mem_alloc_addr or the one obtained using DMA mapping APIs.
116  *
117  * The function returns '0' on success and negative value on failure.
118  */
119 static int pci_epf_test_data_transfer(struct pci_epf_test *epf_test,
120 				      dma_addr_t dma_dst, dma_addr_t dma_src,
121 				      size_t len, dma_addr_t dma_remote,
122 				      enum dma_transfer_direction dir)
123 {
124 	struct dma_chan *chan = (dir == DMA_MEM_TO_DEV) ?
125 				 epf_test->dma_chan_tx : epf_test->dma_chan_rx;
126 	dma_addr_t dma_local = (dir == DMA_MEM_TO_DEV) ? dma_src : dma_dst;
127 	enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
128 	struct pci_epf *epf = epf_test->epf;
129 	struct dma_async_tx_descriptor *tx;
130 	struct dma_slave_config sconf = {};
131 	struct device *dev = &epf->dev;
132 	int ret;
133 
134 	if (IS_ERR_OR_NULL(chan)) {
135 		dev_err(dev, "Invalid DMA memcpy channel\n");
136 		return -EINVAL;
137 	}
138 
139 	if (epf_test->dma_private) {
140 		sconf.direction = dir;
141 		if (dir == DMA_MEM_TO_DEV)
142 			sconf.dst_addr = dma_remote;
143 		else
144 			sconf.src_addr = dma_remote;
145 
146 		if (dmaengine_slave_config(chan, &sconf)) {
147 			dev_err(dev, "DMA slave config fail\n");
148 			return -EIO;
149 		}
150 		tx = dmaengine_prep_slave_single(chan, dma_local, len, dir,
151 						 flags);
152 	} else {
153 		tx = dmaengine_prep_dma_memcpy(chan, dma_dst, dma_src, len,
154 					       flags);
155 	}
156 
157 	if (!tx) {
158 		dev_err(dev, "Failed to prepare DMA memcpy\n");
159 		return -EIO;
160 	}
161 
162 	reinit_completion(&epf_test->transfer_complete);
163 	epf_test->transfer_chan = chan;
164 	tx->callback = pci_epf_test_dma_callback;
165 	tx->callback_param = epf_test;
166 	epf_test->transfer_cookie = dmaengine_submit(tx);
167 
168 	ret = dma_submit_error(epf_test->transfer_cookie);
169 	if (ret) {
170 		dev_err(dev, "Failed to do DMA tx_submit %d\n", ret);
171 		goto terminate;
172 	}
173 
174 	dma_async_issue_pending(chan);
175 	ret = wait_for_completion_interruptible(&epf_test->transfer_complete);
176 	if (ret < 0) {
177 		dev_err(dev, "DMA wait_for_completion interrupted\n");
178 		goto terminate;
179 	}
180 
181 	if (epf_test->transfer_status == DMA_ERROR) {
182 		dev_err(dev, "DMA transfer failed\n");
183 		ret = -EIO;
184 	}
185 
186 terminate:
187 	dmaengine_terminate_sync(chan);
188 
189 	return ret;
190 }
191 
192 struct epf_dma_filter {
193 	struct device *dev;
194 	u32 dma_mask;
195 };
196 
197 static bool epf_dma_filter_fn(struct dma_chan *chan, void *node)
198 {
199 	struct epf_dma_filter *filter = node;
200 	struct dma_slave_caps caps;
201 
202 	memset(&caps, 0, sizeof(caps));
203 	dma_get_slave_caps(chan, &caps);
204 
205 	return chan->device->dev == filter->dev
206 		&& (filter->dma_mask & caps.directions);
207 }
208 
209 /**
210  * pci_epf_test_init_dma_chan() - Function to initialize EPF test DMA channel
211  * @epf_test: the EPF test device that performs data transfer operation
212  *
213  * Function to initialize EPF test DMA channel.
214  */
215 static int pci_epf_test_init_dma_chan(struct pci_epf_test *epf_test)
216 {
217 	struct pci_epf *epf = epf_test->epf;
218 	struct device *dev = &epf->dev;
219 	struct epf_dma_filter filter;
220 	struct dma_chan *dma_chan;
221 	dma_cap_mask_t mask;
222 	int ret;
223 
224 	filter.dev = epf->epc->dev.parent;
225 	filter.dma_mask = BIT(DMA_DEV_TO_MEM);
226 
227 	dma_cap_zero(mask);
228 	dma_cap_set(DMA_SLAVE, mask);
229 	dma_chan = dma_request_channel(mask, epf_dma_filter_fn, &filter);
230 	if (!dma_chan) {
231 		dev_info(dev, "Failed to get private DMA rx channel. Falling back to generic one\n");
232 		goto fail_back_tx;
233 	}
234 
235 	epf_test->dma_chan_rx = dma_chan;
236 
237 	filter.dma_mask = BIT(DMA_MEM_TO_DEV);
238 	dma_chan = dma_request_channel(mask, epf_dma_filter_fn, &filter);
239 
240 	if (!dma_chan) {
241 		dev_info(dev, "Failed to get private DMA tx channel. Falling back to generic one\n");
242 		goto fail_back_rx;
243 	}
244 
245 	epf_test->dma_chan_tx = dma_chan;
246 	epf_test->dma_private = true;
247 
248 	init_completion(&epf_test->transfer_complete);
249 
250 	return 0;
251 
252 fail_back_rx:
253 	dma_release_channel(epf_test->dma_chan_rx);
254 	epf_test->dma_chan_tx = NULL;
255 
256 fail_back_tx:
257 	dma_cap_zero(mask);
258 	dma_cap_set(DMA_MEMCPY, mask);
259 
260 	dma_chan = dma_request_chan_by_mask(&mask);
261 	if (IS_ERR(dma_chan)) {
262 		ret = PTR_ERR(dma_chan);
263 		if (ret != -EPROBE_DEFER)
264 			dev_err(dev, "Failed to get DMA channel\n");
265 		return ret;
266 	}
267 	init_completion(&epf_test->transfer_complete);
268 
269 	epf_test->dma_chan_tx = epf_test->dma_chan_rx = dma_chan;
270 
271 	return 0;
272 }
273 
274 /**
275  * pci_epf_test_clean_dma_chan() - Function to cleanup EPF test DMA channel
276  * @epf_test: the EPF test device that performs data transfer operation
277  *
278  * Helper to cleanup EPF test DMA channel.
279  */
280 static void pci_epf_test_clean_dma_chan(struct pci_epf_test *epf_test)
281 {
282 	if (!epf_test->dma_supported)
283 		return;
284 
285 	dma_release_channel(epf_test->dma_chan_tx);
286 	if (epf_test->dma_chan_tx == epf_test->dma_chan_rx) {
287 		epf_test->dma_chan_tx = NULL;
288 		epf_test->dma_chan_rx = NULL;
289 		return;
290 	}
291 
292 	dma_release_channel(epf_test->dma_chan_rx);
293 	epf_test->dma_chan_rx = NULL;
294 
295 	return;
296 }
297 
298 static void pci_epf_test_print_rate(struct pci_epf_test *epf_test,
299 				    const char *op, u64 size,
300 				    struct timespec64 *start,
301 				    struct timespec64 *end, bool dma)
302 {
303 	struct timespec64 ts = timespec64_sub(*end, *start);
304 	u64 rate = 0, ns;
305 
306 	/* calculate the rate */
307 	ns = timespec64_to_ns(&ts);
308 	if (ns)
309 		rate = div64_u64(size * NSEC_PER_SEC, ns * 1000);
310 
311 	dev_info(&epf_test->epf->dev,
312 		 "%s => Size: %llu B, DMA: %s, Time: %llu.%09u s, Rate: %llu KB/s\n",
313 		 op, size, dma ? "YES" : "NO",
314 		 (u64)ts.tv_sec, (u32)ts.tv_nsec, rate);
315 }
316 
317 static void pci_epf_test_copy(struct pci_epf_test *epf_test,
318 			      struct pci_epf_test_reg *reg)
319 {
320 	int ret;
321 	void __iomem *src_addr;
322 	void __iomem *dst_addr;
323 	phys_addr_t src_phys_addr;
324 	phys_addr_t dst_phys_addr;
325 	struct timespec64 start, end;
326 	struct pci_epf *epf = epf_test->epf;
327 	struct device *dev = &epf->dev;
328 	struct pci_epc *epc = epf->epc;
329 
330 	src_addr = pci_epc_mem_alloc_addr(epc, &src_phys_addr, reg->size);
331 	if (!src_addr) {
332 		dev_err(dev, "Failed to allocate source address\n");
333 		reg->status = STATUS_SRC_ADDR_INVALID;
334 		ret = -ENOMEM;
335 		goto err;
336 	}
337 
338 	ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, src_phys_addr,
339 			       reg->src_addr, reg->size);
340 	if (ret) {
341 		dev_err(dev, "Failed to map source address\n");
342 		reg->status = STATUS_SRC_ADDR_INVALID;
343 		goto err_src_addr;
344 	}
345 
346 	dst_addr = pci_epc_mem_alloc_addr(epc, &dst_phys_addr, reg->size);
347 	if (!dst_addr) {
348 		dev_err(dev, "Failed to allocate destination address\n");
349 		reg->status = STATUS_DST_ADDR_INVALID;
350 		ret = -ENOMEM;
351 		goto err_src_map_addr;
352 	}
353 
354 	ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, dst_phys_addr,
355 			       reg->dst_addr, reg->size);
356 	if (ret) {
357 		dev_err(dev, "Failed to map destination address\n");
358 		reg->status = STATUS_DST_ADDR_INVALID;
359 		goto err_dst_addr;
360 	}
361 
362 	ktime_get_ts64(&start);
363 	if (reg->flags & FLAG_USE_DMA) {
364 		if (epf_test->dma_private) {
365 			dev_err(dev, "Cannot transfer data using DMA\n");
366 			ret = -EINVAL;
367 			goto err_map_addr;
368 		}
369 
370 		ret = pci_epf_test_data_transfer(epf_test, dst_phys_addr,
371 						 src_phys_addr, reg->size, 0,
372 						 DMA_MEM_TO_MEM);
373 		if (ret)
374 			dev_err(dev, "Data transfer failed\n");
375 	} else {
376 		void *buf;
377 
378 		buf = kzalloc(reg->size, GFP_KERNEL);
379 		if (!buf) {
380 			ret = -ENOMEM;
381 			goto err_map_addr;
382 		}
383 
384 		memcpy_fromio(buf, src_addr, reg->size);
385 		memcpy_toio(dst_addr, buf, reg->size);
386 		kfree(buf);
387 	}
388 	ktime_get_ts64(&end);
389 	pci_epf_test_print_rate(epf_test, "COPY", reg->size, &start, &end,
390 				reg->flags & FLAG_USE_DMA);
391 
392 err_map_addr:
393 	pci_epc_unmap_addr(epc, epf->func_no, epf->vfunc_no, dst_phys_addr);
394 
395 err_dst_addr:
396 	pci_epc_mem_free_addr(epc, dst_phys_addr, dst_addr, reg->size);
397 
398 err_src_map_addr:
399 	pci_epc_unmap_addr(epc, epf->func_no, epf->vfunc_no, src_phys_addr);
400 
401 err_src_addr:
402 	pci_epc_mem_free_addr(epc, src_phys_addr, src_addr, reg->size);
403 
404 err:
405 	if (!ret)
406 		reg->status |= STATUS_COPY_SUCCESS;
407 	else
408 		reg->status |= STATUS_COPY_FAIL;
409 }
410 
411 static void pci_epf_test_read(struct pci_epf_test *epf_test,
412 			      struct pci_epf_test_reg *reg)
413 {
414 	int ret;
415 	void __iomem *src_addr;
416 	void *buf;
417 	u32 crc32;
418 	phys_addr_t phys_addr;
419 	phys_addr_t dst_phys_addr;
420 	struct timespec64 start, end;
421 	struct pci_epf *epf = epf_test->epf;
422 	struct device *dev = &epf->dev;
423 	struct pci_epc *epc = epf->epc;
424 	struct device *dma_dev = epf->epc->dev.parent;
425 
426 	src_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
427 	if (!src_addr) {
428 		dev_err(dev, "Failed to allocate address\n");
429 		reg->status = STATUS_SRC_ADDR_INVALID;
430 		ret = -ENOMEM;
431 		goto err;
432 	}
433 
434 	ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, phys_addr,
435 			       reg->src_addr, reg->size);
436 	if (ret) {
437 		dev_err(dev, "Failed to map address\n");
438 		reg->status = STATUS_SRC_ADDR_INVALID;
439 		goto err_addr;
440 	}
441 
442 	buf = kzalloc(reg->size, GFP_KERNEL);
443 	if (!buf) {
444 		ret = -ENOMEM;
445 		goto err_map_addr;
446 	}
447 
448 	if (reg->flags & FLAG_USE_DMA) {
449 		dst_phys_addr = dma_map_single(dma_dev, buf, reg->size,
450 					       DMA_FROM_DEVICE);
451 		if (dma_mapping_error(dma_dev, dst_phys_addr)) {
452 			dev_err(dev, "Failed to map destination buffer addr\n");
453 			ret = -ENOMEM;
454 			goto err_dma_map;
455 		}
456 
457 		ktime_get_ts64(&start);
458 		ret = pci_epf_test_data_transfer(epf_test, dst_phys_addr,
459 						 phys_addr, reg->size,
460 						 reg->src_addr, DMA_DEV_TO_MEM);
461 		if (ret)
462 			dev_err(dev, "Data transfer failed\n");
463 		ktime_get_ts64(&end);
464 
465 		dma_unmap_single(dma_dev, dst_phys_addr, reg->size,
466 				 DMA_FROM_DEVICE);
467 	} else {
468 		ktime_get_ts64(&start);
469 		memcpy_fromio(buf, src_addr, reg->size);
470 		ktime_get_ts64(&end);
471 	}
472 
473 	pci_epf_test_print_rate(epf_test, "READ", reg->size, &start, &end,
474 				reg->flags & FLAG_USE_DMA);
475 
476 	crc32 = crc32_le(~0, buf, reg->size);
477 	if (crc32 != reg->checksum)
478 		ret = -EIO;
479 
480 err_dma_map:
481 	kfree(buf);
482 
483 err_map_addr:
484 	pci_epc_unmap_addr(epc, epf->func_no, epf->vfunc_no, phys_addr);
485 
486 err_addr:
487 	pci_epc_mem_free_addr(epc, phys_addr, src_addr, reg->size);
488 
489 err:
490 	if (!ret)
491 		reg->status |= STATUS_READ_SUCCESS;
492 	else
493 		reg->status |= STATUS_READ_FAIL;
494 }
495 
496 static void pci_epf_test_write(struct pci_epf_test *epf_test,
497 			       struct pci_epf_test_reg *reg)
498 {
499 	int ret;
500 	void __iomem *dst_addr;
501 	void *buf;
502 	phys_addr_t phys_addr;
503 	phys_addr_t src_phys_addr;
504 	struct timespec64 start, end;
505 	struct pci_epf *epf = epf_test->epf;
506 	struct device *dev = &epf->dev;
507 	struct pci_epc *epc = epf->epc;
508 	struct device *dma_dev = epf->epc->dev.parent;
509 
510 	dst_addr = pci_epc_mem_alloc_addr(epc, &phys_addr, reg->size);
511 	if (!dst_addr) {
512 		dev_err(dev, "Failed to allocate address\n");
513 		reg->status = STATUS_DST_ADDR_INVALID;
514 		ret = -ENOMEM;
515 		goto err;
516 	}
517 
518 	ret = pci_epc_map_addr(epc, epf->func_no, epf->vfunc_no, phys_addr,
519 			       reg->dst_addr, reg->size);
520 	if (ret) {
521 		dev_err(dev, "Failed to map address\n");
522 		reg->status = STATUS_DST_ADDR_INVALID;
523 		goto err_addr;
524 	}
525 
526 	buf = kzalloc(reg->size, GFP_KERNEL);
527 	if (!buf) {
528 		ret = -ENOMEM;
529 		goto err_map_addr;
530 	}
531 
532 	get_random_bytes(buf, reg->size);
533 	reg->checksum = crc32_le(~0, buf, reg->size);
534 
535 	if (reg->flags & FLAG_USE_DMA) {
536 		src_phys_addr = dma_map_single(dma_dev, buf, reg->size,
537 					       DMA_TO_DEVICE);
538 		if (dma_mapping_error(dma_dev, src_phys_addr)) {
539 			dev_err(dev, "Failed to map source buffer addr\n");
540 			ret = -ENOMEM;
541 			goto err_dma_map;
542 		}
543 
544 		ktime_get_ts64(&start);
545 
546 		ret = pci_epf_test_data_transfer(epf_test, phys_addr,
547 						 src_phys_addr, reg->size,
548 						 reg->dst_addr,
549 						 DMA_MEM_TO_DEV);
550 		if (ret)
551 			dev_err(dev, "Data transfer failed\n");
552 		ktime_get_ts64(&end);
553 
554 		dma_unmap_single(dma_dev, src_phys_addr, reg->size,
555 				 DMA_TO_DEVICE);
556 	} else {
557 		ktime_get_ts64(&start);
558 		memcpy_toio(dst_addr, buf, reg->size);
559 		ktime_get_ts64(&end);
560 	}
561 
562 	pci_epf_test_print_rate(epf_test, "WRITE", reg->size, &start, &end,
563 				reg->flags & FLAG_USE_DMA);
564 
565 	/*
566 	 * wait 1ms inorder for the write to complete. Without this delay L3
567 	 * error in observed in the host system.
568 	 */
569 	usleep_range(1000, 2000);
570 
571 err_dma_map:
572 	kfree(buf);
573 
574 err_map_addr:
575 	pci_epc_unmap_addr(epc, epf->func_no, epf->vfunc_no, phys_addr);
576 
577 err_addr:
578 	pci_epc_mem_free_addr(epc, phys_addr, dst_addr, reg->size);
579 
580 err:
581 	if (!ret)
582 		reg->status |= STATUS_WRITE_SUCCESS;
583 	else
584 		reg->status |= STATUS_WRITE_FAIL;
585 }
586 
587 static void pci_epf_test_raise_irq(struct pci_epf_test *epf_test,
588 				   struct pci_epf_test_reg *reg)
589 {
590 	struct pci_epf *epf = epf_test->epf;
591 	struct device *dev = &epf->dev;
592 	struct pci_epc *epc = epf->epc;
593 	u32 status = reg->status | STATUS_IRQ_RAISED;
594 	int count;
595 
596 	/*
597 	 * Set the status before raising the IRQ to ensure that the host sees
598 	 * the updated value when it gets the IRQ.
599 	 */
600 	WRITE_ONCE(reg->status, status);
601 
602 	switch (reg->irq_type) {
603 	case IRQ_TYPE_INTX:
604 		pci_epc_raise_irq(epc, epf->func_no, epf->vfunc_no,
605 				  PCI_IRQ_INTX, 0);
606 		break;
607 	case IRQ_TYPE_MSI:
608 		count = pci_epc_get_msi(epc, epf->func_no, epf->vfunc_no);
609 		if (reg->irq_number > count || count <= 0) {
610 			dev_err(dev, "Invalid MSI IRQ number %d / %d\n",
611 				reg->irq_number, count);
612 			return;
613 		}
614 		pci_epc_raise_irq(epc, epf->func_no, epf->vfunc_no,
615 				  PCI_IRQ_MSI, reg->irq_number);
616 		break;
617 	case IRQ_TYPE_MSIX:
618 		count = pci_epc_get_msix(epc, epf->func_no, epf->vfunc_no);
619 		if (reg->irq_number > count || count <= 0) {
620 			dev_err(dev, "Invalid MSIX IRQ number %d / %d\n",
621 				reg->irq_number, count);
622 			return;
623 		}
624 		pci_epc_raise_irq(epc, epf->func_no, epf->vfunc_no,
625 				  PCI_IRQ_MSIX, reg->irq_number);
626 		break;
627 	default:
628 		dev_err(dev, "Failed to raise IRQ, unknown type\n");
629 		break;
630 	}
631 }
632 
633 static void pci_epf_test_cmd_handler(struct work_struct *work)
634 {
635 	u32 command;
636 	struct pci_epf_test *epf_test = container_of(work, struct pci_epf_test,
637 						     cmd_handler.work);
638 	struct pci_epf *epf = epf_test->epf;
639 	struct device *dev = &epf->dev;
640 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
641 	struct pci_epf_test_reg *reg = epf_test->reg[test_reg_bar];
642 
643 	command = READ_ONCE(reg->command);
644 	if (!command)
645 		goto reset_handler;
646 
647 	WRITE_ONCE(reg->command, 0);
648 	WRITE_ONCE(reg->status, 0);
649 
650 	if ((READ_ONCE(reg->flags) & FLAG_USE_DMA) &&
651 	    !epf_test->dma_supported) {
652 		dev_err(dev, "Cannot transfer data using DMA\n");
653 		goto reset_handler;
654 	}
655 
656 	if (reg->irq_type > IRQ_TYPE_MSIX) {
657 		dev_err(dev, "Failed to detect IRQ type\n");
658 		goto reset_handler;
659 	}
660 
661 	switch (command) {
662 	case COMMAND_RAISE_INTX_IRQ:
663 	case COMMAND_RAISE_MSI_IRQ:
664 	case COMMAND_RAISE_MSIX_IRQ:
665 		pci_epf_test_raise_irq(epf_test, reg);
666 		break;
667 	case COMMAND_WRITE:
668 		pci_epf_test_write(epf_test, reg);
669 		pci_epf_test_raise_irq(epf_test, reg);
670 		break;
671 	case COMMAND_READ:
672 		pci_epf_test_read(epf_test, reg);
673 		pci_epf_test_raise_irq(epf_test, reg);
674 		break;
675 	case COMMAND_COPY:
676 		pci_epf_test_copy(epf_test, reg);
677 		pci_epf_test_raise_irq(epf_test, reg);
678 		break;
679 	default:
680 		dev_err(dev, "Invalid command 0x%x\n", command);
681 		break;
682 	}
683 
684 reset_handler:
685 	queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
686 			   msecs_to_jiffies(1));
687 }
688 
689 static void pci_epf_test_unbind(struct pci_epf *epf)
690 {
691 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
692 	struct pci_epc *epc = epf->epc;
693 	int bar;
694 
695 	cancel_delayed_work(&epf_test->cmd_handler);
696 	pci_epf_test_clean_dma_chan(epf_test);
697 	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
698 		if (!epf_test->reg[bar])
699 			continue;
700 
701 		pci_epc_clear_bar(epc, epf->func_no, epf->vfunc_no,
702 				  &epf->bar[bar]);
703 		pci_epf_free_space(epf, epf_test->reg[bar], bar,
704 				   PRIMARY_INTERFACE);
705 	}
706 }
707 
708 static int pci_epf_test_set_bar(struct pci_epf *epf)
709 {
710 	int bar, ret;
711 	struct pci_epc *epc = epf->epc;
712 	struct device *dev = &epf->dev;
713 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
714 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
715 
716 	for (bar = 0; bar < PCI_STD_NUM_BARS; bar++) {
717 		if (!epf_test->reg[bar])
718 			continue;
719 
720 		ret = pci_epc_set_bar(epc, epf->func_no, epf->vfunc_no,
721 				      &epf->bar[bar]);
722 		if (ret) {
723 			pci_epf_free_space(epf, epf_test->reg[bar], bar,
724 					   PRIMARY_INTERFACE);
725 			dev_err(dev, "Failed to set BAR%d\n", bar);
726 			if (bar == test_reg_bar)
727 				return ret;
728 		}
729 	}
730 
731 	return 0;
732 }
733 
734 static int pci_epf_test_core_init(struct pci_epf *epf)
735 {
736 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
737 	struct pci_epf_header *header = epf->header;
738 	const struct pci_epc_features *epc_features;
739 	struct pci_epc *epc = epf->epc;
740 	struct device *dev = &epf->dev;
741 	bool linkup_notifier = false;
742 	bool msix_capable = false;
743 	bool msi_capable = true;
744 	int ret;
745 
746 	epc_features = pci_epc_get_features(epc, epf->func_no, epf->vfunc_no);
747 	if (epc_features) {
748 		msix_capable = epc_features->msix_capable;
749 		msi_capable = epc_features->msi_capable;
750 	}
751 
752 	if (epf->vfunc_no <= 1) {
753 		ret = pci_epc_write_header(epc, epf->func_no, epf->vfunc_no, header);
754 		if (ret) {
755 			dev_err(dev, "Configuration header write failed\n");
756 			return ret;
757 		}
758 	}
759 
760 	ret = pci_epf_test_set_bar(epf);
761 	if (ret)
762 		return ret;
763 
764 	if (msi_capable) {
765 		ret = pci_epc_set_msi(epc, epf->func_no, epf->vfunc_no,
766 				      epf->msi_interrupts);
767 		if (ret) {
768 			dev_err(dev, "MSI configuration failed\n");
769 			return ret;
770 		}
771 	}
772 
773 	if (msix_capable) {
774 		ret = pci_epc_set_msix(epc, epf->func_no, epf->vfunc_no,
775 				       epf->msix_interrupts,
776 				       epf_test->test_reg_bar,
777 				       epf_test->msix_table_offset);
778 		if (ret) {
779 			dev_err(dev, "MSI-X configuration failed\n");
780 			return ret;
781 		}
782 	}
783 
784 	linkup_notifier = epc_features->linkup_notifier;
785 	if (!linkup_notifier)
786 		queue_work(kpcitest_workqueue, &epf_test->cmd_handler.work);
787 
788 	return 0;
789 }
790 
791 static int pci_epf_test_link_up(struct pci_epf *epf)
792 {
793 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
794 
795 	queue_delayed_work(kpcitest_workqueue, &epf_test->cmd_handler,
796 			   msecs_to_jiffies(1));
797 
798 	return 0;
799 }
800 
801 static const struct pci_epc_event_ops pci_epf_test_event_ops = {
802 	.core_init = pci_epf_test_core_init,
803 	.link_up = pci_epf_test_link_up,
804 };
805 
806 static int pci_epf_test_alloc_space(struct pci_epf *epf)
807 {
808 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
809 	struct device *dev = &epf->dev;
810 	size_t msix_table_size = 0;
811 	size_t test_reg_bar_size;
812 	size_t pba_size = 0;
813 	bool msix_capable;
814 	void *base;
815 	enum pci_barno test_reg_bar = epf_test->test_reg_bar;
816 	enum pci_barno bar;
817 	const struct pci_epc_features *epc_features;
818 	size_t test_reg_size;
819 
820 	epc_features = epf_test->epc_features;
821 
822 	test_reg_bar_size = ALIGN(sizeof(struct pci_epf_test_reg), 128);
823 
824 	msix_capable = epc_features->msix_capable;
825 	if (msix_capable) {
826 		msix_table_size = PCI_MSIX_ENTRY_SIZE * epf->msix_interrupts;
827 		epf_test->msix_table_offset = test_reg_bar_size;
828 		/* Align to QWORD or 8 Bytes */
829 		pba_size = ALIGN(DIV_ROUND_UP(epf->msix_interrupts, 8), 8);
830 	}
831 	test_reg_size = test_reg_bar_size + msix_table_size + pba_size;
832 
833 	base = pci_epf_alloc_space(epf, test_reg_size, test_reg_bar,
834 				   epc_features, PRIMARY_INTERFACE);
835 	if (!base) {
836 		dev_err(dev, "Failed to allocated register space\n");
837 		return -ENOMEM;
838 	}
839 	epf_test->reg[test_reg_bar] = base;
840 
841 	for (bar = BAR_0; bar < PCI_STD_NUM_BARS; bar++) {
842 		bar = pci_epc_get_next_free_bar(epc_features, bar);
843 		if (bar == NO_BAR)
844 			break;
845 
846 		if (bar == test_reg_bar)
847 			continue;
848 
849 		base = pci_epf_alloc_space(epf, bar_size[bar], bar,
850 					   epc_features, PRIMARY_INTERFACE);
851 		if (!base)
852 			dev_err(dev, "Failed to allocate space for BAR%d\n",
853 				bar);
854 		epf_test->reg[bar] = base;
855 	}
856 
857 	return 0;
858 }
859 
860 static int pci_epf_test_bind(struct pci_epf *epf)
861 {
862 	int ret;
863 	struct pci_epf_test *epf_test = epf_get_drvdata(epf);
864 	const struct pci_epc_features *epc_features;
865 	enum pci_barno test_reg_bar = BAR_0;
866 	struct pci_epc *epc = epf->epc;
867 
868 	if (WARN_ON_ONCE(!epc))
869 		return -EINVAL;
870 
871 	epc_features = pci_epc_get_features(epc, epf->func_no, epf->vfunc_no);
872 	if (!epc_features) {
873 		dev_err(&epf->dev, "epc_features not implemented\n");
874 		return -EOPNOTSUPP;
875 	}
876 
877 	test_reg_bar = pci_epc_get_first_free_bar(epc_features);
878 	if (test_reg_bar < 0)
879 		return -EINVAL;
880 
881 	epf_test->test_reg_bar = test_reg_bar;
882 	epf_test->epc_features = epc_features;
883 
884 	ret = pci_epf_test_alloc_space(epf);
885 	if (ret)
886 		return ret;
887 
888 	epf_test->dma_supported = true;
889 
890 	ret = pci_epf_test_init_dma_chan(epf_test);
891 	if (ret)
892 		epf_test->dma_supported = false;
893 
894 	return 0;
895 }
896 
897 static const struct pci_epf_device_id pci_epf_test_ids[] = {
898 	{
899 		.name = "pci_epf_test",
900 	},
901 	{},
902 };
903 
904 static int pci_epf_test_probe(struct pci_epf *epf,
905 			      const struct pci_epf_device_id *id)
906 {
907 	struct pci_epf_test *epf_test;
908 	struct device *dev = &epf->dev;
909 
910 	epf_test = devm_kzalloc(dev, sizeof(*epf_test), GFP_KERNEL);
911 	if (!epf_test)
912 		return -ENOMEM;
913 
914 	epf->header = &test_header;
915 	epf_test->epf = epf;
916 
917 	INIT_DELAYED_WORK(&epf_test->cmd_handler, pci_epf_test_cmd_handler);
918 
919 	epf->event_ops = &pci_epf_test_event_ops;
920 
921 	epf_set_drvdata(epf, epf_test);
922 	return 0;
923 }
924 
925 static const struct pci_epf_ops ops = {
926 	.unbind	= pci_epf_test_unbind,
927 	.bind	= pci_epf_test_bind,
928 };
929 
930 static struct pci_epf_driver test_driver = {
931 	.driver.name	= "pci_epf_test",
932 	.probe		= pci_epf_test_probe,
933 	.id_table	= pci_epf_test_ids,
934 	.ops		= &ops,
935 	.owner		= THIS_MODULE,
936 };
937 
938 static int __init pci_epf_test_init(void)
939 {
940 	int ret;
941 
942 	kpcitest_workqueue = alloc_workqueue("kpcitest",
943 					     WQ_MEM_RECLAIM | WQ_HIGHPRI, 0);
944 	if (!kpcitest_workqueue) {
945 		pr_err("Failed to allocate the kpcitest work queue\n");
946 		return -ENOMEM;
947 	}
948 
949 	ret = pci_epf_register_driver(&test_driver);
950 	if (ret) {
951 		destroy_workqueue(kpcitest_workqueue);
952 		pr_err("Failed to register pci epf test driver --> %d\n", ret);
953 		return ret;
954 	}
955 
956 	return 0;
957 }
958 module_init(pci_epf_test_init);
959 
960 static void __exit pci_epf_test_exit(void)
961 {
962 	if (kpcitest_workqueue)
963 		destroy_workqueue(kpcitest_workqueue);
964 	pci_epf_unregister_driver(&test_driver);
965 }
966 module_exit(pci_epf_test_exit);
967 
968 MODULE_DESCRIPTION("PCI EPF TEST DRIVER");
969 MODULE_AUTHOR("Kishon Vijay Abraham I <kishon@ti.com>");
970 MODULE_LICENSE("GPL v2");
971