xref: /linux/drivers/pci/controller/dwc/pcie-designware-host.c (revision 7a9b709e7cc5ce1ffb84ce07bf6d157e1de758df)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Synopsys DesignWare PCIe host controller driver
4  *
5  * Copyright (C) 2013 Samsung Electronics Co., Ltd.
6  *		https://www.samsung.com
7  *
8  * Author: Jingoo Han <jg1.han@samsung.com>
9  */
10 
11 #include <linux/iopoll.h>
12 #include <linux/irqchip/chained_irq.h>
13 #include <linux/irqdomain.h>
14 #include <linux/msi.h>
15 #include <linux/of_address.h>
16 #include <linux/of_pci.h>
17 #include <linux/pci_regs.h>
18 #include <linux/platform_device.h>
19 
20 #include "../../pci.h"
21 #include "pcie-designware.h"
22 
23 static struct pci_ops dw_pcie_ops;
24 static struct pci_ops dw_child_pcie_ops;
25 
26 static void dw_msi_ack_irq(struct irq_data *d)
27 {
28 	irq_chip_ack_parent(d);
29 }
30 
31 static void dw_msi_mask_irq(struct irq_data *d)
32 {
33 	pci_msi_mask_irq(d);
34 	irq_chip_mask_parent(d);
35 }
36 
37 static void dw_msi_unmask_irq(struct irq_data *d)
38 {
39 	pci_msi_unmask_irq(d);
40 	irq_chip_unmask_parent(d);
41 }
42 
43 static struct irq_chip dw_pcie_msi_irq_chip = {
44 	.name = "PCI-MSI",
45 	.irq_ack = dw_msi_ack_irq,
46 	.irq_mask = dw_msi_mask_irq,
47 	.irq_unmask = dw_msi_unmask_irq,
48 };
49 
50 static struct msi_domain_info dw_pcie_msi_domain_info = {
51 	.flags	= MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
52 		  MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX |
53 		  MSI_FLAG_MULTI_PCI_MSI,
54 	.chip	= &dw_pcie_msi_irq_chip,
55 };
56 
57 /* MSI int handler */
58 irqreturn_t dw_handle_msi_irq(struct dw_pcie_rp *pp)
59 {
60 	int i, pos;
61 	unsigned long val;
62 	u32 status, num_ctrls;
63 	irqreturn_t ret = IRQ_NONE;
64 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
65 
66 	num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
67 
68 	for (i = 0; i < num_ctrls; i++) {
69 		status = dw_pcie_readl_dbi(pci, PCIE_MSI_INTR0_STATUS +
70 					   (i * MSI_REG_CTRL_BLOCK_SIZE));
71 		if (!status)
72 			continue;
73 
74 		ret = IRQ_HANDLED;
75 		val = status;
76 		pos = 0;
77 		while ((pos = find_next_bit(&val, MAX_MSI_IRQS_PER_CTRL,
78 					    pos)) != MAX_MSI_IRQS_PER_CTRL) {
79 			generic_handle_domain_irq(pp->irq_domain,
80 						  (i * MAX_MSI_IRQS_PER_CTRL) +
81 						  pos);
82 			pos++;
83 		}
84 	}
85 
86 	return ret;
87 }
88 
89 /* Chained MSI interrupt service routine */
90 static void dw_chained_msi_isr(struct irq_desc *desc)
91 {
92 	struct irq_chip *chip = irq_desc_get_chip(desc);
93 	struct dw_pcie_rp *pp;
94 
95 	chained_irq_enter(chip, desc);
96 
97 	pp = irq_desc_get_handler_data(desc);
98 	dw_handle_msi_irq(pp);
99 
100 	chained_irq_exit(chip, desc);
101 }
102 
103 static void dw_pci_setup_msi_msg(struct irq_data *d, struct msi_msg *msg)
104 {
105 	struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d);
106 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
107 	u64 msi_target;
108 
109 	msi_target = (u64)pp->msi_data;
110 
111 	msg->address_lo = lower_32_bits(msi_target);
112 	msg->address_hi = upper_32_bits(msi_target);
113 
114 	msg->data = d->hwirq;
115 
116 	dev_dbg(pci->dev, "msi#%d address_hi %#x address_lo %#x\n",
117 		(int)d->hwirq, msg->address_hi, msg->address_lo);
118 }
119 
120 static void dw_pci_bottom_mask(struct irq_data *d)
121 {
122 	struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d);
123 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
124 	unsigned int res, bit, ctrl;
125 	unsigned long flags;
126 
127 	raw_spin_lock_irqsave(&pp->lock, flags);
128 
129 	ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL;
130 	res = ctrl * MSI_REG_CTRL_BLOCK_SIZE;
131 	bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;
132 
133 	pp->irq_mask[ctrl] |= BIT(bit);
134 	dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_MASK + res, pp->irq_mask[ctrl]);
135 
136 	raw_spin_unlock_irqrestore(&pp->lock, flags);
137 }
138 
139 static void dw_pci_bottom_unmask(struct irq_data *d)
140 {
141 	struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d);
142 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
143 	unsigned int res, bit, ctrl;
144 	unsigned long flags;
145 
146 	raw_spin_lock_irqsave(&pp->lock, flags);
147 
148 	ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL;
149 	res = ctrl * MSI_REG_CTRL_BLOCK_SIZE;
150 	bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;
151 
152 	pp->irq_mask[ctrl] &= ~BIT(bit);
153 	dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_MASK + res, pp->irq_mask[ctrl]);
154 
155 	raw_spin_unlock_irqrestore(&pp->lock, flags);
156 }
157 
158 static void dw_pci_bottom_ack(struct irq_data *d)
159 {
160 	struct dw_pcie_rp *pp  = irq_data_get_irq_chip_data(d);
161 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
162 	unsigned int res, bit, ctrl;
163 
164 	ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL;
165 	res = ctrl * MSI_REG_CTRL_BLOCK_SIZE;
166 	bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;
167 
168 	dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_STATUS + res, BIT(bit));
169 }
170 
171 static struct irq_chip dw_pci_msi_bottom_irq_chip = {
172 	.name = "DWPCI-MSI",
173 	.irq_ack = dw_pci_bottom_ack,
174 	.irq_compose_msi_msg = dw_pci_setup_msi_msg,
175 	.irq_mask = dw_pci_bottom_mask,
176 	.irq_unmask = dw_pci_bottom_unmask,
177 };
178 
179 static int dw_pcie_irq_domain_alloc(struct irq_domain *domain,
180 				    unsigned int virq, unsigned int nr_irqs,
181 				    void *args)
182 {
183 	struct dw_pcie_rp *pp = domain->host_data;
184 	unsigned long flags;
185 	u32 i;
186 	int bit;
187 
188 	raw_spin_lock_irqsave(&pp->lock, flags);
189 
190 	bit = bitmap_find_free_region(pp->msi_irq_in_use, pp->num_vectors,
191 				      order_base_2(nr_irqs));
192 
193 	raw_spin_unlock_irqrestore(&pp->lock, flags);
194 
195 	if (bit < 0)
196 		return -ENOSPC;
197 
198 	for (i = 0; i < nr_irqs; i++)
199 		irq_domain_set_info(domain, virq + i, bit + i,
200 				    pp->msi_irq_chip,
201 				    pp, handle_edge_irq,
202 				    NULL, NULL);
203 
204 	return 0;
205 }
206 
207 static void dw_pcie_irq_domain_free(struct irq_domain *domain,
208 				    unsigned int virq, unsigned int nr_irqs)
209 {
210 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
211 	struct dw_pcie_rp *pp = domain->host_data;
212 	unsigned long flags;
213 
214 	raw_spin_lock_irqsave(&pp->lock, flags);
215 
216 	bitmap_release_region(pp->msi_irq_in_use, d->hwirq,
217 			      order_base_2(nr_irqs));
218 
219 	raw_spin_unlock_irqrestore(&pp->lock, flags);
220 }
221 
222 static const struct irq_domain_ops dw_pcie_msi_domain_ops = {
223 	.alloc	= dw_pcie_irq_domain_alloc,
224 	.free	= dw_pcie_irq_domain_free,
225 };
226 
227 int dw_pcie_allocate_domains(struct dw_pcie_rp *pp)
228 {
229 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
230 	struct fwnode_handle *fwnode = of_node_to_fwnode(pci->dev->of_node);
231 
232 	pp->irq_domain = irq_domain_create_linear(fwnode, pp->num_vectors,
233 					       &dw_pcie_msi_domain_ops, pp);
234 	if (!pp->irq_domain) {
235 		dev_err(pci->dev, "Failed to create IRQ domain\n");
236 		return -ENOMEM;
237 	}
238 
239 	irq_domain_update_bus_token(pp->irq_domain, DOMAIN_BUS_NEXUS);
240 
241 	pp->msi_domain = pci_msi_create_irq_domain(fwnode,
242 						   &dw_pcie_msi_domain_info,
243 						   pp->irq_domain);
244 	if (!pp->msi_domain) {
245 		dev_err(pci->dev, "Failed to create MSI domain\n");
246 		irq_domain_remove(pp->irq_domain);
247 		return -ENOMEM;
248 	}
249 
250 	return 0;
251 }
252 
253 static void dw_pcie_free_msi(struct dw_pcie_rp *pp)
254 {
255 	u32 ctrl;
256 
257 	for (ctrl = 0; ctrl < MAX_MSI_CTRLS; ctrl++) {
258 		if (pp->msi_irq[ctrl] > 0)
259 			irq_set_chained_handler_and_data(pp->msi_irq[ctrl],
260 							 NULL, NULL);
261 	}
262 
263 	irq_domain_remove(pp->msi_domain);
264 	irq_domain_remove(pp->irq_domain);
265 }
266 
267 static void dw_pcie_msi_init(struct dw_pcie_rp *pp)
268 {
269 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
270 	u64 msi_target = (u64)pp->msi_data;
271 
272 	if (!pci_msi_enabled() || !pp->has_msi_ctrl)
273 		return;
274 
275 	/* Program the msi_data */
276 	dw_pcie_writel_dbi(pci, PCIE_MSI_ADDR_LO, lower_32_bits(msi_target));
277 	dw_pcie_writel_dbi(pci, PCIE_MSI_ADDR_HI, upper_32_bits(msi_target));
278 }
279 
280 static int dw_pcie_parse_split_msi_irq(struct dw_pcie_rp *pp)
281 {
282 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
283 	struct device *dev = pci->dev;
284 	struct platform_device *pdev = to_platform_device(dev);
285 	u32 ctrl, max_vectors;
286 	int irq;
287 
288 	/* Parse any "msiX" IRQs described in the devicetree */
289 	for (ctrl = 0; ctrl < MAX_MSI_CTRLS; ctrl++) {
290 		char msi_name[] = "msiX";
291 
292 		msi_name[3] = '0' + ctrl;
293 		irq = platform_get_irq_byname_optional(pdev, msi_name);
294 		if (irq == -ENXIO)
295 			break;
296 		if (irq < 0)
297 			return dev_err_probe(dev, irq,
298 					     "Failed to parse MSI IRQ '%s'\n",
299 					     msi_name);
300 
301 		pp->msi_irq[ctrl] = irq;
302 	}
303 
304 	/* If no "msiX" IRQs, caller should fallback to "msi" IRQ */
305 	if (ctrl == 0)
306 		return -ENXIO;
307 
308 	max_vectors = ctrl * MAX_MSI_IRQS_PER_CTRL;
309 	if (pp->num_vectors > max_vectors) {
310 		dev_warn(dev, "Exceeding number of MSI vectors, limiting to %u\n",
311 			 max_vectors);
312 		pp->num_vectors = max_vectors;
313 	}
314 	if (!pp->num_vectors)
315 		pp->num_vectors = max_vectors;
316 
317 	return 0;
318 }
319 
320 static int dw_pcie_msi_host_init(struct dw_pcie_rp *pp)
321 {
322 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
323 	struct device *dev = pci->dev;
324 	struct platform_device *pdev = to_platform_device(dev);
325 	u64 *msi_vaddr = NULL;
326 	int ret;
327 	u32 ctrl, num_ctrls;
328 
329 	for (ctrl = 0; ctrl < MAX_MSI_CTRLS; ctrl++)
330 		pp->irq_mask[ctrl] = ~0;
331 
332 	if (!pp->msi_irq[0]) {
333 		ret = dw_pcie_parse_split_msi_irq(pp);
334 		if (ret < 0 && ret != -ENXIO)
335 			return ret;
336 	}
337 
338 	if (!pp->num_vectors)
339 		pp->num_vectors = MSI_DEF_NUM_VECTORS;
340 	num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
341 
342 	if (!pp->msi_irq[0]) {
343 		pp->msi_irq[0] = platform_get_irq_byname_optional(pdev, "msi");
344 		if (pp->msi_irq[0] < 0) {
345 			pp->msi_irq[0] = platform_get_irq(pdev, 0);
346 			if (pp->msi_irq[0] < 0)
347 				return pp->msi_irq[0];
348 		}
349 	}
350 
351 	dev_dbg(dev, "Using %d MSI vectors\n", pp->num_vectors);
352 
353 	pp->msi_irq_chip = &dw_pci_msi_bottom_irq_chip;
354 
355 	ret = dw_pcie_allocate_domains(pp);
356 	if (ret)
357 		return ret;
358 
359 	for (ctrl = 0; ctrl < num_ctrls; ctrl++) {
360 		if (pp->msi_irq[ctrl] > 0)
361 			irq_set_chained_handler_and_data(pp->msi_irq[ctrl],
362 						    dw_chained_msi_isr, pp);
363 	}
364 
365 	/*
366 	 * Even though the iMSI-RX Module supports 64-bit addresses some
367 	 * peripheral PCIe devices may lack 64-bit message support. In
368 	 * order not to miss MSI TLPs from those devices the MSI target
369 	 * address has to be within the lowest 4GB.
370 	 *
371 	 * Note until there is a better alternative found the reservation is
372 	 * done by allocating from the artificially limited DMA-coherent
373 	 * memory.
374 	 */
375 	ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
376 	if (!ret)
377 		msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data,
378 						GFP_KERNEL);
379 
380 	if (!msi_vaddr) {
381 		dev_warn(dev, "Failed to allocate 32-bit MSI address\n");
382 		dma_set_coherent_mask(dev, DMA_BIT_MASK(64));
383 		msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data,
384 						GFP_KERNEL);
385 		if (!msi_vaddr) {
386 			dev_err(dev, "Failed to allocate MSI address\n");
387 			dw_pcie_free_msi(pp);
388 			return -ENOMEM;
389 		}
390 	}
391 
392 	return 0;
393 }
394 
395 static void dw_pcie_host_request_msg_tlp_res(struct dw_pcie_rp *pp)
396 {
397 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
398 	struct resource_entry *win;
399 	struct resource *res;
400 
401 	win = resource_list_first_type(&pp->bridge->windows, IORESOURCE_MEM);
402 	if (win) {
403 		res = devm_kzalloc(pci->dev, sizeof(*res), GFP_KERNEL);
404 		if (!res)
405 			return;
406 
407 		/*
408 		 * Allocate MSG TLP region of size 'region_align' at the end of
409 		 * the host bridge window.
410 		 */
411 		res->start = win->res->end - pci->region_align + 1;
412 		res->end = win->res->end;
413 		res->name = "msg";
414 		res->flags = win->res->flags | IORESOURCE_BUSY;
415 
416 		if (!devm_request_resource(pci->dev, win->res, res))
417 			pp->msg_res = res;
418 	}
419 }
420 
421 static int dw_pcie_host_get_resources(struct dw_pcie_rp *pp)
422 {
423 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
424 	struct device *dev = pci->dev;
425 	struct platform_device *pdev = to_platform_device(dev);
426 	struct resource_entry *win;
427 	struct resource *res;
428 	int ret;
429 
430 	ret = dw_pcie_get_resources(pci);
431 	if (ret)
432 		return ret;
433 
434 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "config");
435 	if (!res) {
436 		dev_err(dev, "Missing \"config\" reg space\n");
437 		return -ENODEV;
438 	}
439 
440 	pp->cfg0_size = resource_size(res);
441 	pp->cfg0_base = res->start;
442 
443 	pp->va_cfg0_base = devm_pci_remap_cfg_resource(dev, res);
444 	if (IS_ERR(pp->va_cfg0_base))
445 		return PTR_ERR(pp->va_cfg0_base);
446 
447 	/* Get the I/O range from DT */
448 	win = resource_list_first_type(&pp->bridge->windows, IORESOURCE_IO);
449 	if (win) {
450 		pp->io_size = resource_size(win->res);
451 		pp->io_bus_addr = win->res->start - win->offset;
452 		pp->io_base = pci_pio_to_address(win->res->start);
453 	}
454 
455 	/*
456 	 * visconti_pcie_cpu_addr_fixup() uses pp->io_base, so we have to
457 	 * call dw_pcie_parent_bus_offset() after setting pp->io_base.
458 	 */
459 	pci->parent_bus_offset = dw_pcie_parent_bus_offset(pci, "config",
460 							   pp->cfg0_base);
461 	return 0;
462 }
463 
464 int dw_pcie_host_init(struct dw_pcie_rp *pp)
465 {
466 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
467 	struct device *dev = pci->dev;
468 	struct device_node *np = dev->of_node;
469 	struct pci_host_bridge *bridge;
470 	int ret;
471 
472 	raw_spin_lock_init(&pp->lock);
473 
474 	bridge = devm_pci_alloc_host_bridge(dev, 0);
475 	if (!bridge)
476 		return -ENOMEM;
477 
478 	pp->bridge = bridge;
479 
480 	ret = dw_pcie_host_get_resources(pp);
481 	if (ret)
482 		return ret;
483 
484 	/* Set default bus ops */
485 	bridge->ops = &dw_pcie_ops;
486 	bridge->child_ops = &dw_child_pcie_ops;
487 
488 	if (pp->ops->init) {
489 		ret = pp->ops->init(pp);
490 		if (ret)
491 			return ret;
492 	}
493 
494 	if (pci_msi_enabled()) {
495 		pp->has_msi_ctrl = !(pp->ops->msi_init ||
496 				     of_property_present(np, "msi-parent") ||
497 				     of_property_present(np, "msi-map"));
498 
499 		/*
500 		 * For the has_msi_ctrl case the default assignment is handled
501 		 * in the dw_pcie_msi_host_init().
502 		 */
503 		if (!pp->has_msi_ctrl && !pp->num_vectors) {
504 			pp->num_vectors = MSI_DEF_NUM_VECTORS;
505 		} else if (pp->num_vectors > MAX_MSI_IRQS) {
506 			dev_err(dev, "Invalid number of vectors\n");
507 			ret = -EINVAL;
508 			goto err_deinit_host;
509 		}
510 
511 		if (pp->ops->msi_init) {
512 			ret = pp->ops->msi_init(pp);
513 			if (ret < 0)
514 				goto err_deinit_host;
515 		} else if (pp->has_msi_ctrl) {
516 			ret = dw_pcie_msi_host_init(pp);
517 			if (ret < 0)
518 				goto err_deinit_host;
519 		}
520 	}
521 
522 	dw_pcie_version_detect(pci);
523 
524 	dw_pcie_iatu_detect(pci);
525 
526 	/*
527 	 * Allocate the resource for MSG TLP before programming the iATU
528 	 * outbound window in dw_pcie_setup_rc(). Since the allocation depends
529 	 * on the value of 'region_align', this has to be done after
530 	 * dw_pcie_iatu_detect().
531 	 *
532 	 * Glue drivers need to set 'use_atu_msg' before dw_pcie_host_init() to
533 	 * make use of the generic MSG TLP implementation.
534 	 */
535 	if (pp->use_atu_msg)
536 		dw_pcie_host_request_msg_tlp_res(pp);
537 
538 	ret = dw_pcie_edma_detect(pci);
539 	if (ret)
540 		goto err_free_msi;
541 
542 	ret = dw_pcie_setup_rc(pp);
543 	if (ret)
544 		goto err_remove_edma;
545 
546 	if (!dw_pcie_link_up(pci)) {
547 		ret = dw_pcie_start_link(pci);
548 		if (ret)
549 			goto err_remove_edma;
550 	}
551 
552 	/*
553 	 * Note: Skip the link up delay only when a Link Up IRQ is present.
554 	 * If there is no Link Up IRQ, we should not bypass the delay
555 	 * because that would require users to manually rescan for devices.
556 	 */
557 	if (!pp->use_linkup_irq)
558 		/* Ignore errors, the link may come up later */
559 		dw_pcie_wait_for_link(pci);
560 
561 	bridge->sysdata = pp;
562 
563 	ret = pci_host_probe(bridge);
564 	if (ret)
565 		goto err_stop_link;
566 
567 	if (pp->ops->post_init)
568 		pp->ops->post_init(pp);
569 
570 	dwc_pcie_debugfs_init(pci);
571 
572 	return 0;
573 
574 err_stop_link:
575 	dw_pcie_stop_link(pci);
576 
577 err_remove_edma:
578 	dw_pcie_edma_remove(pci);
579 
580 err_free_msi:
581 	if (pp->has_msi_ctrl)
582 		dw_pcie_free_msi(pp);
583 
584 err_deinit_host:
585 	if (pp->ops->deinit)
586 		pp->ops->deinit(pp);
587 
588 	return ret;
589 }
590 EXPORT_SYMBOL_GPL(dw_pcie_host_init);
591 
592 void dw_pcie_host_deinit(struct dw_pcie_rp *pp)
593 {
594 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
595 
596 	dwc_pcie_debugfs_deinit(pci);
597 
598 	pci_stop_root_bus(pp->bridge->bus);
599 	pci_remove_root_bus(pp->bridge->bus);
600 
601 	dw_pcie_stop_link(pci);
602 
603 	dw_pcie_edma_remove(pci);
604 
605 	if (pp->has_msi_ctrl)
606 		dw_pcie_free_msi(pp);
607 
608 	if (pp->ops->deinit)
609 		pp->ops->deinit(pp);
610 }
611 EXPORT_SYMBOL_GPL(dw_pcie_host_deinit);
612 
613 static void __iomem *dw_pcie_other_conf_map_bus(struct pci_bus *bus,
614 						unsigned int devfn, int where)
615 {
616 	struct dw_pcie_rp *pp = bus->sysdata;
617 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
618 	struct dw_pcie_ob_atu_cfg atu = { 0 };
619 	int type, ret;
620 	u32 busdev;
621 
622 	/*
623 	 * Checking whether the link is up here is a last line of defense
624 	 * against platforms that forward errors on the system bus as
625 	 * SError upon PCI configuration transactions issued when the link
626 	 * is down. This check is racy by definition and does not stop
627 	 * the system from triggering an SError if the link goes down
628 	 * after this check is performed.
629 	 */
630 	if (!dw_pcie_link_up(pci))
631 		return NULL;
632 
633 	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
634 		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
635 
636 	if (pci_is_root_bus(bus->parent))
637 		type = PCIE_ATU_TYPE_CFG0;
638 	else
639 		type = PCIE_ATU_TYPE_CFG1;
640 
641 	atu.type = type;
642 	atu.parent_bus_addr = pp->cfg0_base - pci->parent_bus_offset;
643 	atu.pci_addr = busdev;
644 	atu.size = pp->cfg0_size;
645 
646 	ret = dw_pcie_prog_outbound_atu(pci, &atu);
647 	if (ret)
648 		return NULL;
649 
650 	return pp->va_cfg0_base + where;
651 }
652 
653 static int dw_pcie_rd_other_conf(struct pci_bus *bus, unsigned int devfn,
654 				 int where, int size, u32 *val)
655 {
656 	struct dw_pcie_rp *pp = bus->sysdata;
657 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
658 	struct dw_pcie_ob_atu_cfg atu = { 0 };
659 	int ret;
660 
661 	ret = pci_generic_config_read(bus, devfn, where, size, val);
662 	if (ret != PCIBIOS_SUCCESSFUL)
663 		return ret;
664 
665 	if (pp->cfg0_io_shared) {
666 		atu.type = PCIE_ATU_TYPE_IO;
667 		atu.parent_bus_addr = pp->io_base - pci->parent_bus_offset;
668 		atu.pci_addr = pp->io_bus_addr;
669 		atu.size = pp->io_size;
670 
671 		ret = dw_pcie_prog_outbound_atu(pci, &atu);
672 		if (ret)
673 			return PCIBIOS_SET_FAILED;
674 	}
675 
676 	return PCIBIOS_SUCCESSFUL;
677 }
678 
679 static int dw_pcie_wr_other_conf(struct pci_bus *bus, unsigned int devfn,
680 				 int where, int size, u32 val)
681 {
682 	struct dw_pcie_rp *pp = bus->sysdata;
683 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
684 	struct dw_pcie_ob_atu_cfg atu = { 0 };
685 	int ret;
686 
687 	ret = pci_generic_config_write(bus, devfn, where, size, val);
688 	if (ret != PCIBIOS_SUCCESSFUL)
689 		return ret;
690 
691 	if (pp->cfg0_io_shared) {
692 		atu.type = PCIE_ATU_TYPE_IO;
693 		atu.parent_bus_addr = pp->io_base - pci->parent_bus_offset;
694 		atu.pci_addr = pp->io_bus_addr;
695 		atu.size = pp->io_size;
696 
697 		ret = dw_pcie_prog_outbound_atu(pci, &atu);
698 		if (ret)
699 			return PCIBIOS_SET_FAILED;
700 	}
701 
702 	return PCIBIOS_SUCCESSFUL;
703 }
704 
705 static struct pci_ops dw_child_pcie_ops = {
706 	.map_bus = dw_pcie_other_conf_map_bus,
707 	.read = dw_pcie_rd_other_conf,
708 	.write = dw_pcie_wr_other_conf,
709 };
710 
711 void __iomem *dw_pcie_own_conf_map_bus(struct pci_bus *bus, unsigned int devfn, int where)
712 {
713 	struct dw_pcie_rp *pp = bus->sysdata;
714 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
715 
716 	if (PCI_SLOT(devfn) > 0)
717 		return NULL;
718 
719 	return pci->dbi_base + where;
720 }
721 EXPORT_SYMBOL_GPL(dw_pcie_own_conf_map_bus);
722 
723 static struct pci_ops dw_pcie_ops = {
724 	.map_bus = dw_pcie_own_conf_map_bus,
725 	.read = pci_generic_config_read,
726 	.write = pci_generic_config_write,
727 };
728 
729 static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp)
730 {
731 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
732 	struct dw_pcie_ob_atu_cfg atu = { 0 };
733 	struct resource_entry *entry;
734 	int i, ret;
735 
736 	/* Note the very first outbound ATU is used for CFG IOs */
737 	if (!pci->num_ob_windows) {
738 		dev_err(pci->dev, "No outbound iATU found\n");
739 		return -EINVAL;
740 	}
741 
742 	/*
743 	 * Ensure all out/inbound windows are disabled before proceeding with
744 	 * the MEM/IO (dma-)ranges setups.
745 	 */
746 	for (i = 0; i < pci->num_ob_windows; i++)
747 		dw_pcie_disable_atu(pci, PCIE_ATU_REGION_DIR_OB, i);
748 
749 	for (i = 0; i < pci->num_ib_windows; i++)
750 		dw_pcie_disable_atu(pci, PCIE_ATU_REGION_DIR_IB, i);
751 
752 	i = 0;
753 	resource_list_for_each_entry(entry, &pp->bridge->windows) {
754 		if (resource_type(entry->res) != IORESOURCE_MEM)
755 			continue;
756 
757 		if (pci->num_ob_windows <= ++i)
758 			break;
759 
760 		atu.index = i;
761 		atu.type = PCIE_ATU_TYPE_MEM;
762 		atu.parent_bus_addr = entry->res->start - pci->parent_bus_offset;
763 		atu.pci_addr = entry->res->start - entry->offset;
764 
765 		/* Adjust iATU size if MSG TLP region was allocated before */
766 		if (pp->msg_res && pp->msg_res->parent == entry->res)
767 			atu.size = resource_size(entry->res) -
768 					resource_size(pp->msg_res);
769 		else
770 			atu.size = resource_size(entry->res);
771 
772 		ret = dw_pcie_prog_outbound_atu(pci, &atu);
773 		if (ret) {
774 			dev_err(pci->dev, "Failed to set MEM range %pr\n",
775 				entry->res);
776 			return ret;
777 		}
778 	}
779 
780 	if (pp->io_size) {
781 		if (pci->num_ob_windows > ++i) {
782 			atu.index = i;
783 			atu.type = PCIE_ATU_TYPE_IO;
784 			atu.parent_bus_addr = pp->io_base - pci->parent_bus_offset;
785 			atu.pci_addr = pp->io_bus_addr;
786 			atu.size = pp->io_size;
787 
788 			ret = dw_pcie_prog_outbound_atu(pci, &atu);
789 			if (ret) {
790 				dev_err(pci->dev, "Failed to set IO range %pr\n",
791 					entry->res);
792 				return ret;
793 			}
794 		} else {
795 			pp->cfg0_io_shared = true;
796 		}
797 	}
798 
799 	if (pci->num_ob_windows <= i)
800 		dev_warn(pci->dev, "Ranges exceed outbound iATU size (%d)\n",
801 			 pci->num_ob_windows);
802 
803 	pp->msg_atu_index = i;
804 
805 	i = 0;
806 	resource_list_for_each_entry(entry, &pp->bridge->dma_ranges) {
807 		if (resource_type(entry->res) != IORESOURCE_MEM)
808 			continue;
809 
810 		if (pci->num_ib_windows <= i)
811 			break;
812 
813 		ret = dw_pcie_prog_inbound_atu(pci, i++, PCIE_ATU_TYPE_MEM,
814 					       entry->res->start,
815 					       entry->res->start - entry->offset,
816 					       resource_size(entry->res));
817 		if (ret) {
818 			dev_err(pci->dev, "Failed to set DMA range %pr\n",
819 				entry->res);
820 			return ret;
821 		}
822 	}
823 
824 	if (pci->num_ib_windows <= i)
825 		dev_warn(pci->dev, "Dma-ranges exceed inbound iATU size (%u)\n",
826 			 pci->num_ib_windows);
827 
828 	return 0;
829 }
830 
831 int dw_pcie_setup_rc(struct dw_pcie_rp *pp)
832 {
833 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
834 	u32 val, ctrl, num_ctrls;
835 	int ret;
836 
837 	/*
838 	 * Enable DBI read-only registers for writing/updating configuration.
839 	 * Write permission gets disabled towards the end of this function.
840 	 */
841 	dw_pcie_dbi_ro_wr_en(pci);
842 
843 	dw_pcie_setup(pci);
844 
845 	if (pp->has_msi_ctrl) {
846 		num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
847 
848 		/* Initialize IRQ Status array */
849 		for (ctrl = 0; ctrl < num_ctrls; ctrl++) {
850 			dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_MASK +
851 					    (ctrl * MSI_REG_CTRL_BLOCK_SIZE),
852 					    pp->irq_mask[ctrl]);
853 			dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_ENABLE +
854 					    (ctrl * MSI_REG_CTRL_BLOCK_SIZE),
855 					    ~0);
856 		}
857 	}
858 
859 	dw_pcie_msi_init(pp);
860 
861 	/* Setup RC BARs */
862 	dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, 0x00000004);
863 	dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_1, 0x00000000);
864 
865 	/* Setup interrupt pins */
866 	val = dw_pcie_readl_dbi(pci, PCI_INTERRUPT_LINE);
867 	val &= 0xffff00ff;
868 	val |= 0x00000100;
869 	dw_pcie_writel_dbi(pci, PCI_INTERRUPT_LINE, val);
870 
871 	/* Setup bus numbers */
872 	val = dw_pcie_readl_dbi(pci, PCI_PRIMARY_BUS);
873 	val &= 0xff000000;
874 	val |= 0x00ff0100;
875 	dw_pcie_writel_dbi(pci, PCI_PRIMARY_BUS, val);
876 
877 	/* Setup command register */
878 	val = dw_pcie_readl_dbi(pci, PCI_COMMAND);
879 	val &= 0xffff0000;
880 	val |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY |
881 		PCI_COMMAND_MASTER | PCI_COMMAND_SERR;
882 	dw_pcie_writel_dbi(pci, PCI_COMMAND, val);
883 
884 	/*
885 	 * If the platform provides its own child bus config accesses, it means
886 	 * the platform uses its own address translation component rather than
887 	 * ATU, so we should not program the ATU here.
888 	 */
889 	if (pp->bridge->child_ops == &dw_child_pcie_ops) {
890 		ret = dw_pcie_iatu_setup(pp);
891 		if (ret)
892 			return ret;
893 	}
894 
895 	dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, 0);
896 
897 	/* Program correct class for RC */
898 	dw_pcie_writew_dbi(pci, PCI_CLASS_DEVICE, PCI_CLASS_BRIDGE_PCI);
899 
900 	val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
901 	val |= PORT_LOGIC_SPEED_CHANGE;
902 	dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
903 
904 	dw_pcie_dbi_ro_wr_dis(pci);
905 
906 	return 0;
907 }
908 EXPORT_SYMBOL_GPL(dw_pcie_setup_rc);
909 
910 static int dw_pcie_pme_turn_off(struct dw_pcie *pci)
911 {
912 	struct dw_pcie_ob_atu_cfg atu = { 0 };
913 	void __iomem *mem;
914 	int ret;
915 
916 	if (pci->num_ob_windows <= pci->pp.msg_atu_index)
917 		return -ENOSPC;
918 
919 	if (!pci->pp.msg_res)
920 		return -ENOSPC;
921 
922 	atu.code = PCIE_MSG_CODE_PME_TURN_OFF;
923 	atu.routing = PCIE_MSG_TYPE_R_BC;
924 	atu.type = PCIE_ATU_TYPE_MSG;
925 	atu.size = resource_size(pci->pp.msg_res);
926 	atu.index = pci->pp.msg_atu_index;
927 
928 	atu.parent_bus_addr = pci->pp.msg_res->start - pci->parent_bus_offset;
929 
930 	ret = dw_pcie_prog_outbound_atu(pci, &atu);
931 	if (ret)
932 		return ret;
933 
934 	mem = ioremap(pci->pp.msg_res->start, pci->region_align);
935 	if (!mem)
936 		return -ENOMEM;
937 
938 	/* A dummy write is converted to a Msg TLP */
939 	writel(0, mem);
940 
941 	iounmap(mem);
942 
943 	return 0;
944 }
945 
946 int dw_pcie_suspend_noirq(struct dw_pcie *pci)
947 {
948 	u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
949 	u32 val;
950 	int ret;
951 
952 	/*
953 	 * If L1SS is supported, then do not put the link into L2 as some
954 	 * devices such as NVMe expect low resume latency.
955 	 */
956 	if (dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKCTL) & PCI_EXP_LNKCTL_ASPM_L1)
957 		return 0;
958 
959 	if (pci->pp.ops->pme_turn_off) {
960 		pci->pp.ops->pme_turn_off(&pci->pp);
961 	} else {
962 		ret = dw_pcie_pme_turn_off(pci);
963 		if (ret)
964 			return ret;
965 	}
966 
967 	ret = read_poll_timeout(dw_pcie_get_ltssm, val,
968 				val == DW_PCIE_LTSSM_L2_IDLE ||
969 				val <= DW_PCIE_LTSSM_DETECT_WAIT,
970 				PCIE_PME_TO_L2_TIMEOUT_US/10,
971 				PCIE_PME_TO_L2_TIMEOUT_US, false, pci);
972 	if (ret) {
973 		/* Only log message when LTSSM isn't in DETECT or POLL */
974 		dev_err(pci->dev, "Timeout waiting for L2 entry! LTSSM: 0x%x\n", val);
975 		return ret;
976 	}
977 
978 	/*
979 	 * Per PCIe r6.0, sec 5.3.3.2.1, software should wait at least
980 	 * 100ns after L2/L3 Ready before turning off refclock and
981 	 * main power. This is harmless when no endpoint is connected.
982 	 */
983 	udelay(1);
984 
985 	dw_pcie_stop_link(pci);
986 	if (pci->pp.ops->deinit)
987 		pci->pp.ops->deinit(&pci->pp);
988 
989 	pci->suspended = true;
990 
991 	return ret;
992 }
993 EXPORT_SYMBOL_GPL(dw_pcie_suspend_noirq);
994 
995 int dw_pcie_resume_noirq(struct dw_pcie *pci)
996 {
997 	int ret;
998 
999 	if (!pci->suspended)
1000 		return 0;
1001 
1002 	pci->suspended = false;
1003 
1004 	if (pci->pp.ops->init) {
1005 		ret = pci->pp.ops->init(&pci->pp);
1006 		if (ret) {
1007 			dev_err(pci->dev, "Host init failed: %d\n", ret);
1008 			return ret;
1009 		}
1010 	}
1011 
1012 	dw_pcie_setup_rc(&pci->pp);
1013 
1014 	ret = dw_pcie_start_link(pci);
1015 	if (ret)
1016 		return ret;
1017 
1018 	ret = dw_pcie_wait_for_link(pci);
1019 	if (ret)
1020 		return ret;
1021 
1022 	return ret;
1023 }
1024 EXPORT_SYMBOL_GPL(dw_pcie_resume_noirq);
1025