xref: /linux/drivers/pci/controller/dwc/pcie-designware-host.c (revision 2f2c7254931f41b5736e3ba12aaa9ac1bbeeeb92)
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/align.h>
12 #include <linux/iopoll.h>
13 #include <linux/irqchip/chained_irq.h>
14 #include <linux/irqchip/irq-msi-lib.h>
15 #include <linux/irqdomain.h>
16 #include <linux/msi.h>
17 #include <linux/of_address.h>
18 #include <linux/of_pci.h>
19 #include <linux/pci_regs.h>
20 #include <linux/platform_device.h>
21 
22 #include "../../pci.h"
23 #include "pcie-designware.h"
24 
25 static struct pci_ops dw_pcie_ops;
26 static struct pci_ops dw_child_pcie_ops;
27 
28 #define DW_PCIE_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS		| \
29 				    MSI_FLAG_USE_DEF_CHIP_OPS		| \
30 				    MSI_FLAG_NO_AFFINITY		| \
31 				    MSI_FLAG_PCI_MSI_MASK_PARENT)
32 #define DW_PCIE_MSI_FLAGS_SUPPORTED (MSI_FLAG_MULTI_PCI_MSI		| \
33 				     MSI_FLAG_PCI_MSIX			| \
34 				     MSI_GENERIC_FLAGS_MASK)
35 
36 #define IS_256MB_ALIGNED(x) IS_ALIGNED(x, SZ_256M)
37 
38 static const struct msi_parent_ops dw_pcie_msi_parent_ops = {
39 	.required_flags		= DW_PCIE_MSI_FLAGS_REQUIRED,
40 	.supported_flags	= DW_PCIE_MSI_FLAGS_SUPPORTED,
41 	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
42 	.chip_flags		= MSI_CHIP_FLAG_SET_ACK,
43 	.prefix			= "DW-",
44 	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
45 };
46 
47 /* MSI int handler */
dw_handle_msi_irq(struct dw_pcie_rp * pp)48 irqreturn_t dw_handle_msi_irq(struct dw_pcie_rp *pp)
49 {
50 	int i, pos;
51 	unsigned long val;
52 	u32 status, num_ctrls;
53 	irqreturn_t ret = IRQ_NONE;
54 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
55 
56 	num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
57 
58 	for (i = 0; i < num_ctrls; i++) {
59 		status = dw_pcie_readl_dbi(pci, PCIE_MSI_INTR0_STATUS +
60 					   (i * MSI_REG_CTRL_BLOCK_SIZE));
61 		if (!status)
62 			continue;
63 
64 		ret = IRQ_HANDLED;
65 		val = status;
66 		pos = 0;
67 		while ((pos = find_next_bit(&val, MAX_MSI_IRQS_PER_CTRL,
68 					    pos)) != MAX_MSI_IRQS_PER_CTRL) {
69 			generic_handle_domain_irq(pp->irq_domain,
70 						  (i * MAX_MSI_IRQS_PER_CTRL) +
71 						  pos);
72 			pos++;
73 		}
74 	}
75 
76 	return ret;
77 }
78 
79 /* Chained MSI interrupt service routine */
dw_chained_msi_isr(struct irq_desc * desc)80 static void dw_chained_msi_isr(struct irq_desc *desc)
81 {
82 	struct irq_chip *chip = irq_desc_get_chip(desc);
83 	struct dw_pcie_rp *pp;
84 
85 	chained_irq_enter(chip, desc);
86 
87 	pp = irq_desc_get_handler_data(desc);
88 	dw_handle_msi_irq(pp);
89 
90 	chained_irq_exit(chip, desc);
91 }
92 
dw_pci_setup_msi_msg(struct irq_data * d,struct msi_msg * msg)93 static void dw_pci_setup_msi_msg(struct irq_data *d, struct msi_msg *msg)
94 {
95 	struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d);
96 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
97 	u64 msi_target;
98 
99 	msi_target = (u64)pp->msi_data;
100 
101 	msg->address_lo = lower_32_bits(msi_target);
102 	msg->address_hi = upper_32_bits(msi_target);
103 
104 	msg->data = d->hwirq;
105 
106 	dev_dbg(pci->dev, "msi#%d address_hi %#x address_lo %#x\n",
107 		(int)d->hwirq, msg->address_hi, msg->address_lo);
108 }
109 
dw_pci_bottom_mask(struct irq_data * d)110 static void dw_pci_bottom_mask(struct irq_data *d)
111 {
112 	struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d);
113 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
114 	unsigned int res, bit, ctrl;
115 	unsigned long flags;
116 
117 	raw_spin_lock_irqsave(&pp->lock, flags);
118 
119 	ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL;
120 	res = ctrl * MSI_REG_CTRL_BLOCK_SIZE;
121 	bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;
122 
123 	pp->irq_mask[ctrl] |= BIT(bit);
124 	dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_MASK + res, pp->irq_mask[ctrl]);
125 
126 	raw_spin_unlock_irqrestore(&pp->lock, flags);
127 }
128 
dw_pci_bottom_unmask(struct irq_data * d)129 static void dw_pci_bottom_unmask(struct irq_data *d)
130 {
131 	struct dw_pcie_rp *pp = irq_data_get_irq_chip_data(d);
132 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
133 	unsigned int res, bit, ctrl;
134 	unsigned long flags;
135 
136 	raw_spin_lock_irqsave(&pp->lock, flags);
137 
138 	ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL;
139 	res = ctrl * MSI_REG_CTRL_BLOCK_SIZE;
140 	bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;
141 
142 	pp->irq_mask[ctrl] &= ~BIT(bit);
143 	dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_MASK + res, pp->irq_mask[ctrl]);
144 
145 	raw_spin_unlock_irqrestore(&pp->lock, flags);
146 }
147 
dw_pci_bottom_ack(struct irq_data * d)148 static void dw_pci_bottom_ack(struct irq_data *d)
149 {
150 	struct dw_pcie_rp *pp  = irq_data_get_irq_chip_data(d);
151 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
152 	unsigned int res, bit, ctrl;
153 
154 	ctrl = d->hwirq / MAX_MSI_IRQS_PER_CTRL;
155 	res = ctrl * MSI_REG_CTRL_BLOCK_SIZE;
156 	bit = d->hwirq % MAX_MSI_IRQS_PER_CTRL;
157 
158 	dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_STATUS + res, BIT(bit));
159 }
160 
161 static struct irq_chip dw_pci_msi_bottom_irq_chip = {
162 	.name = "DWPCI-MSI",
163 	.irq_ack = dw_pci_bottom_ack,
164 	.irq_compose_msi_msg = dw_pci_setup_msi_msg,
165 	.irq_mask = dw_pci_bottom_mask,
166 	.irq_unmask = dw_pci_bottom_unmask,
167 };
168 
dw_pcie_irq_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * args)169 static int dw_pcie_irq_domain_alloc(struct irq_domain *domain,
170 				    unsigned int virq, unsigned int nr_irqs,
171 				    void *args)
172 {
173 	struct dw_pcie_rp *pp = domain->host_data;
174 	unsigned long flags;
175 	u32 i;
176 	int bit;
177 
178 	raw_spin_lock_irqsave(&pp->lock, flags);
179 
180 	bit = bitmap_find_free_region(pp->msi_irq_in_use, pp->num_vectors,
181 				      order_base_2(nr_irqs));
182 
183 	raw_spin_unlock_irqrestore(&pp->lock, flags);
184 
185 	if (bit < 0)
186 		return -ENOSPC;
187 
188 	for (i = 0; i < nr_irqs; i++)
189 		irq_domain_set_info(domain, virq + i, bit + i,
190 				    pp->msi_irq_chip,
191 				    pp, handle_edge_irq,
192 				    NULL, NULL);
193 
194 	return 0;
195 }
196 
dw_pcie_irq_domain_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)197 static void dw_pcie_irq_domain_free(struct irq_domain *domain,
198 				    unsigned int virq, unsigned int nr_irqs)
199 {
200 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
201 	struct dw_pcie_rp *pp = domain->host_data;
202 	unsigned long flags;
203 
204 	raw_spin_lock_irqsave(&pp->lock, flags);
205 
206 	bitmap_release_region(pp->msi_irq_in_use, d->hwirq,
207 			      order_base_2(nr_irqs));
208 
209 	raw_spin_unlock_irqrestore(&pp->lock, flags);
210 }
211 
212 static const struct irq_domain_ops dw_pcie_msi_domain_ops = {
213 	.alloc	= dw_pcie_irq_domain_alloc,
214 	.free	= dw_pcie_irq_domain_free,
215 };
216 
dw_pcie_allocate_domains(struct dw_pcie_rp * pp)217 int dw_pcie_allocate_domains(struct dw_pcie_rp *pp)
218 {
219 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
220 	struct irq_domain_info info = {
221 		.fwnode		= dev_fwnode(pci->dev),
222 		.ops		= &dw_pcie_msi_domain_ops,
223 		.size		= pp->num_vectors,
224 		.host_data	= pp,
225 	};
226 
227 	pp->irq_domain = msi_create_parent_irq_domain(&info, &dw_pcie_msi_parent_ops);
228 	if (!pp->irq_domain) {
229 		dev_err(pci->dev, "Failed to create IRQ domain\n");
230 		return -ENOMEM;
231 	}
232 
233 	return 0;
234 }
235 
dw_pcie_free_msi(struct dw_pcie_rp * pp)236 void dw_pcie_free_msi(struct dw_pcie_rp *pp)
237 {
238 	u32 ctrl;
239 
240 	for (ctrl = 0; ctrl < MAX_MSI_CTRLS; ctrl++) {
241 		if (pp->msi_irq[ctrl] > 0)
242 			irq_set_chained_handler_and_data(pp->msi_irq[ctrl],
243 							 NULL, NULL);
244 	}
245 
246 	irq_domain_remove(pp->irq_domain);
247 }
248 EXPORT_SYMBOL_GPL(dw_pcie_free_msi);
249 
dw_pcie_msi_init(struct dw_pcie_rp * pp)250 void dw_pcie_msi_init(struct dw_pcie_rp *pp)
251 {
252 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
253 	u64 msi_target = (u64)pp->msi_data;
254 	u32 ctrl, num_ctrls;
255 
256 	if (!pci_msi_enabled() || !pp->has_msi_ctrl)
257 		return;
258 
259 	num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
260 
261 	/* Initialize IRQ Status array */
262 	for (ctrl = 0; ctrl < num_ctrls; ctrl++) {
263 		dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_MASK +
264 				    (ctrl * MSI_REG_CTRL_BLOCK_SIZE),
265 				    pp->irq_mask[ctrl]);
266 		dw_pcie_writel_dbi(pci, PCIE_MSI_INTR0_ENABLE +
267 				    (ctrl * MSI_REG_CTRL_BLOCK_SIZE),
268 				    ~0);
269 	}
270 
271 	/* Program the msi_data */
272 	dw_pcie_writel_dbi(pci, PCIE_MSI_ADDR_LO, lower_32_bits(msi_target));
273 	dw_pcie_writel_dbi(pci, PCIE_MSI_ADDR_HI, upper_32_bits(msi_target));
274 }
275 EXPORT_SYMBOL_GPL(dw_pcie_msi_init);
276 
dw_pcie_parse_split_msi_irq(struct dw_pcie_rp * pp)277 static int dw_pcie_parse_split_msi_irq(struct dw_pcie_rp *pp)
278 {
279 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
280 	struct device *dev = pci->dev;
281 	struct platform_device *pdev = to_platform_device(dev);
282 	u32 ctrl, max_vectors;
283 	int irq;
284 
285 	/* Parse any "msiX" IRQs described in the devicetree */
286 	for (ctrl = 0; ctrl < MAX_MSI_CTRLS; ctrl++) {
287 		char msi_name[] = "msiX";
288 
289 		msi_name[3] = '0' + ctrl;
290 		irq = platform_get_irq_byname_optional(pdev, msi_name);
291 		if (irq == -ENXIO)
292 			break;
293 		if (irq < 0)
294 			return dev_err_probe(dev, irq,
295 					     "Failed to parse MSI IRQ '%s'\n",
296 					     msi_name);
297 
298 		pp->msi_irq[ctrl] = irq;
299 	}
300 
301 	/* If no "msiX" IRQs, caller should fallback to "msi" IRQ */
302 	if (ctrl == 0)
303 		return -ENXIO;
304 
305 	max_vectors = ctrl * MAX_MSI_IRQS_PER_CTRL;
306 	if (pp->num_vectors > max_vectors) {
307 		dev_warn(dev, "Exceeding number of MSI vectors, limiting to %u\n",
308 			 max_vectors);
309 		pp->num_vectors = max_vectors;
310 	}
311 	if (!pp->num_vectors)
312 		pp->num_vectors = max_vectors;
313 
314 	return 0;
315 }
316 
dw_pcie_msi_host_init(struct dw_pcie_rp * pp)317 int dw_pcie_msi_host_init(struct dw_pcie_rp *pp)
318 {
319 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
320 	struct device *dev = pci->dev;
321 	struct platform_device *pdev = to_platform_device(dev);
322 	u64 *msi_vaddr = NULL;
323 	int ret;
324 	u32 ctrl, num_ctrls;
325 
326 	for (ctrl = 0; ctrl < MAX_MSI_CTRLS; ctrl++)
327 		pp->irq_mask[ctrl] = ~0;
328 
329 	if (!pp->msi_irq[0]) {
330 		ret = dw_pcie_parse_split_msi_irq(pp);
331 		if (ret < 0 && ret != -ENXIO)
332 			return ret;
333 	}
334 
335 	if (!pp->num_vectors)
336 		pp->num_vectors = MSI_DEF_NUM_VECTORS;
337 	num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
338 
339 	if (!pp->msi_irq[0]) {
340 		pp->msi_irq[0] = platform_get_irq_byname_optional(pdev, "msi");
341 		if (pp->msi_irq[0] < 0) {
342 			pp->msi_irq[0] = platform_get_irq(pdev, 0);
343 			if (pp->msi_irq[0] < 0)
344 				return pp->msi_irq[0];
345 		}
346 	}
347 
348 	dev_dbg(dev, "Using %d MSI vectors\n", pp->num_vectors);
349 
350 	pp->msi_irq_chip = &dw_pci_msi_bottom_irq_chip;
351 
352 	ret = dw_pcie_allocate_domains(pp);
353 	if (ret)
354 		return ret;
355 
356 	for (ctrl = 0; ctrl < num_ctrls; ctrl++) {
357 		if (pp->msi_irq[ctrl] > 0)
358 			irq_set_chained_handler_and_data(pp->msi_irq[ctrl],
359 						    dw_chained_msi_isr, pp);
360 	}
361 
362 	/*
363 	 * Even though the iMSI-RX Module supports 64-bit addresses some
364 	 * peripheral PCIe devices may lack 64-bit message support. In
365 	 * order not to miss MSI TLPs from those devices the MSI target
366 	 * address has to be within the lowest 4GB.
367 	 *
368 	 * Note until there is a better alternative found the reservation is
369 	 * done by allocating from the artificially limited DMA-coherent
370 	 * memory.
371 	 */
372 	ret = dma_set_coherent_mask(dev, DMA_BIT_MASK(32));
373 	if (!ret)
374 		msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data,
375 						GFP_KERNEL);
376 
377 	if (!msi_vaddr) {
378 		dev_warn(dev, "Failed to allocate 32-bit MSI address\n");
379 		dma_set_coherent_mask(dev, DMA_BIT_MASK(64));
380 		msi_vaddr = dmam_alloc_coherent(dev, sizeof(u64), &pp->msi_data,
381 						GFP_KERNEL);
382 		if (!msi_vaddr) {
383 			dev_err(dev, "Failed to allocate MSI address\n");
384 			dw_pcie_free_msi(pp);
385 			return -ENOMEM;
386 		}
387 	}
388 
389 	return 0;
390 }
391 EXPORT_SYMBOL_GPL(dw_pcie_msi_host_init);
392 
dw_pcie_host_request_msg_tlp_res(struct dw_pcie_rp * pp)393 static void dw_pcie_host_request_msg_tlp_res(struct dw_pcie_rp *pp)
394 {
395 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
396 	struct resource_entry *win;
397 	struct resource *res;
398 
399 	win = resource_list_first_type(&pp->bridge->windows, IORESOURCE_MEM);
400 	if (win) {
401 		res = devm_kzalloc(pci->dev, sizeof(*res), GFP_KERNEL);
402 		if (!res)
403 			return;
404 
405 		/*
406 		 * Allocate MSG TLP region of size 'region_align' at the end of
407 		 * the host bridge window.
408 		 */
409 		res->start = win->res->end - pci->region_align + 1;
410 		res->end = win->res->end;
411 		res->name = "msg";
412 		res->flags = win->res->flags | IORESOURCE_BUSY;
413 
414 		if (!devm_request_resource(pci->dev, win->res, res))
415 			pp->msg_res = res;
416 	}
417 }
418 
dw_pcie_config_ecam_iatu(struct dw_pcie_rp * pp)419 static int dw_pcie_config_ecam_iatu(struct dw_pcie_rp *pp)
420 {
421 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
422 	struct dw_pcie_ob_atu_cfg atu = {0};
423 	resource_size_t bus_range_max;
424 	struct resource_entry *bus;
425 	int ret;
426 
427 	bus = resource_list_first_type(&pp->bridge->windows, IORESOURCE_BUS);
428 
429 	/*
430 	 * Root bus under the host bridge doesn't require any iATU configuration
431 	 * as DBI region will be used to access root bus config space.
432 	 * Immediate bus under Root Bus, needs type 0 iATU configuration and
433 	 * remaining buses need type 1 iATU configuration.
434 	 */
435 	atu.index = 0;
436 	atu.type = PCIE_ATU_TYPE_CFG0;
437 	atu.parent_bus_addr = pp->cfg0_base + SZ_1M;
438 	/* 1MiB is to cover 1 (bus) * 32 (devices) * 8 (functions) */
439 	atu.size = SZ_1M;
440 	atu.ctrl2 = PCIE_ATU_CFG_SHIFT_MODE_ENABLE;
441 	ret = dw_pcie_prog_outbound_atu(pci, &atu);
442 	if (ret)
443 		return ret;
444 
445 	bus_range_max = resource_size(bus->res);
446 
447 	if (bus_range_max < 2)
448 		return 0;
449 
450 	/* Configure remaining buses in type 1 iATU configuration */
451 	atu.index = 1;
452 	atu.type = PCIE_ATU_TYPE_CFG1;
453 	atu.parent_bus_addr = pp->cfg0_base + SZ_2M;
454 	atu.size = (SZ_1M * bus_range_max) - SZ_2M;
455 	atu.ctrl2 = PCIE_ATU_CFG_SHIFT_MODE_ENABLE;
456 
457 	return dw_pcie_prog_outbound_atu(pci, &atu);
458 }
459 
dw_pcie_create_ecam_window(struct dw_pcie_rp * pp,struct resource * res)460 static int dw_pcie_create_ecam_window(struct dw_pcie_rp *pp, struct resource *res)
461 {
462 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
463 	struct device *dev = pci->dev;
464 	struct resource_entry *bus;
465 
466 	bus = resource_list_first_type(&pp->bridge->windows, IORESOURCE_BUS);
467 	if (!bus)
468 		return -ENODEV;
469 
470 	pp->cfg = pci_ecam_create(dev, res, bus->res, &pci_generic_ecam_ops);
471 	if (IS_ERR(pp->cfg))
472 		return PTR_ERR(pp->cfg);
473 
474 	pci->dbi_base = pp->cfg->win;
475 	pci->dbi_phys_addr = res->start;
476 
477 	return 0;
478 }
479 
dw_pcie_ecam_enabled(struct dw_pcie_rp * pp,struct resource * config_res)480 static bool dw_pcie_ecam_enabled(struct dw_pcie_rp *pp, struct resource *config_res)
481 {
482 	struct resource *bus_range;
483 	u64 nr_buses;
484 
485 	/* Vendor glue drivers may implement their own ECAM mechanism */
486 	if (pp->native_ecam)
487 		return false;
488 
489 	/*
490 	 * PCIe spec r6.0, sec 7.2.2 mandates the base address used for ECAM to
491 	 * be aligned on a 2^(n+20) byte boundary, where n is the number of bits
492 	 * used for representing 'bus' in BDF. Since the DWC cores always use 8
493 	 * bits for representing 'bus', the base address has to be aligned to
494 	 * 2^28 byte boundary, which is 256 MiB.
495 	 */
496 	if (!IS_256MB_ALIGNED(config_res->start))
497 		return false;
498 
499 	bus_range = resource_list_first_type(&pp->bridge->windows, IORESOURCE_BUS)->res;
500 	if (!bus_range)
501 		return false;
502 
503 	nr_buses = resource_size(config_res) >> PCIE_ECAM_BUS_SHIFT;
504 
505 	return nr_buses >= resource_size(bus_range);
506 }
507 
dw_pcie_host_get_resources(struct dw_pcie_rp * pp)508 static int dw_pcie_host_get_resources(struct dw_pcie_rp *pp)
509 {
510 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
511 	struct device *dev = pci->dev;
512 	struct platform_device *pdev = to_platform_device(dev);
513 	struct resource_entry *win;
514 	struct resource *res;
515 	int ret;
516 
517 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "config");
518 	if (!res) {
519 		dev_err(dev, "Missing \"config\" reg space\n");
520 		return -ENODEV;
521 	}
522 
523 	pp->cfg0_size = resource_size(res);
524 	pp->cfg0_base = res->start;
525 
526 	pp->ecam_enabled = dw_pcie_ecam_enabled(pp, res);
527 	if (pp->ecam_enabled) {
528 		ret = dw_pcie_create_ecam_window(pp, res);
529 		if (ret)
530 			return ret;
531 
532 		pp->bridge->ops = (struct pci_ops *)&pci_generic_ecam_ops.pci_ops;
533 		pp->bridge->sysdata = pp->cfg;
534 		pp->cfg->priv = pp;
535 	} else {
536 		pp->va_cfg0_base = devm_pci_remap_cfg_resource(dev, res);
537 		if (IS_ERR(pp->va_cfg0_base))
538 			return PTR_ERR(pp->va_cfg0_base);
539 
540 		/* Set default bus ops */
541 		pp->bridge->ops = &dw_pcie_ops;
542 		pp->bridge->child_ops = &dw_child_pcie_ops;
543 		pp->bridge->sysdata = pp;
544 	}
545 
546 	ret = dw_pcie_get_resources(pci);
547 	if (ret) {
548 		if (pp->cfg)
549 			pci_ecam_free(pp->cfg);
550 		return ret;
551 	}
552 
553 	/* Get the I/O range from DT */
554 	win = resource_list_first_type(&pp->bridge->windows, IORESOURCE_IO);
555 	if (win) {
556 		pp->io_size = resource_size(win->res);
557 		pp->io_bus_addr = win->res->start - win->offset;
558 		pp->io_base = pci_pio_to_address(win->res->start);
559 	}
560 
561 	/*
562 	 * visconti_pcie_cpu_addr_fixup() uses pp->io_base, so we have to
563 	 * call dw_pcie_parent_bus_offset() after setting pp->io_base.
564 	 */
565 	pci->parent_bus_offset = dw_pcie_parent_bus_offset(pci, "config",
566 							   pp->cfg0_base);
567 	return 0;
568 }
569 
dw_pcie_host_init(struct dw_pcie_rp * pp)570 int dw_pcie_host_init(struct dw_pcie_rp *pp)
571 {
572 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
573 	struct device *dev = pci->dev;
574 	struct device_node *np = dev->of_node;
575 	struct pci_host_bridge *bridge;
576 	int ret;
577 
578 	raw_spin_lock_init(&pp->lock);
579 
580 	bridge = devm_pci_alloc_host_bridge(dev, 0);
581 	if (!bridge)
582 		return -ENOMEM;
583 
584 	pp->bridge = bridge;
585 
586 	ret = dw_pcie_host_get_resources(pp);
587 	if (ret)
588 		return ret;
589 
590 	if (pp->ops->init) {
591 		ret = pp->ops->init(pp);
592 		if (ret)
593 			goto err_free_ecam;
594 	}
595 
596 	if (pci_msi_enabled()) {
597 		pp->has_msi_ctrl = !(pp->ops->msi_init ||
598 				     of_property_present(np, "msi-parent") ||
599 				     of_property_present(np, "msi-map"));
600 
601 		/*
602 		 * For the has_msi_ctrl case the default assignment is handled
603 		 * in the dw_pcie_msi_host_init().
604 		 */
605 		if (!pp->has_msi_ctrl && !pp->num_vectors) {
606 			pp->num_vectors = MSI_DEF_NUM_VECTORS;
607 		} else if (pp->num_vectors > MAX_MSI_IRQS) {
608 			dev_err(dev, "Invalid number of vectors\n");
609 			ret = -EINVAL;
610 			goto err_deinit_host;
611 		}
612 
613 		if (pp->ops->msi_init) {
614 			ret = pp->ops->msi_init(pp);
615 			if (ret < 0)
616 				goto err_deinit_host;
617 		} else if (pp->has_msi_ctrl) {
618 			ret = dw_pcie_msi_host_init(pp);
619 			if (ret < 0)
620 				goto err_deinit_host;
621 		}
622 	}
623 
624 	dw_pcie_version_detect(pci);
625 
626 	dw_pcie_iatu_detect(pci);
627 
628 	if (pci->num_lanes < 1)
629 		pci->num_lanes = dw_pcie_link_get_max_link_width(pci);
630 
631 	ret = of_pci_get_equalization_presets(dev, &pp->presets, pci->num_lanes);
632 	if (ret)
633 		goto err_free_msi;
634 
635 	if (pp->ecam_enabled) {
636 		ret = dw_pcie_config_ecam_iatu(pp);
637 		if (ret) {
638 			dev_err(dev, "Failed to configure iATU in ECAM mode\n");
639 			goto err_free_msi;
640 		}
641 	}
642 
643 	/*
644 	 * Allocate the resource for MSG TLP before programming the iATU
645 	 * outbound window in dw_pcie_setup_rc(). Since the allocation depends
646 	 * on the value of 'region_align', this has to be done after
647 	 * dw_pcie_iatu_detect().
648 	 *
649 	 * Glue drivers need to set 'use_atu_msg' before dw_pcie_host_init() to
650 	 * make use of the generic MSG TLP implementation.
651 	 */
652 	if (pp->use_atu_msg)
653 		dw_pcie_host_request_msg_tlp_res(pp);
654 
655 	ret = dw_pcie_edma_detect(pci);
656 	if (ret)
657 		goto err_free_msi;
658 
659 	ret = dw_pcie_setup_rc(pp);
660 	if (ret)
661 		goto err_remove_edma;
662 
663 	if (!dw_pcie_link_up(pci)) {
664 		ret = dw_pcie_start_link(pci);
665 		if (ret)
666 			goto err_remove_edma;
667 	}
668 
669 	/*
670 	 * Note: Skip the link up delay only when a Link Up IRQ is present.
671 	 * If there is no Link Up IRQ, we should not bypass the delay
672 	 * because that would require users to manually rescan for devices.
673 	 */
674 	if (!pp->use_linkup_irq)
675 		/* Ignore errors, the link may come up later */
676 		dw_pcie_wait_for_link(pci);
677 
678 	ret = pci_host_probe(bridge);
679 	if (ret)
680 		goto err_stop_link;
681 
682 	if (pp->ops->post_init)
683 		pp->ops->post_init(pp);
684 
685 	dwc_pcie_debugfs_init(pci, DW_PCIE_RC_TYPE);
686 
687 	return 0;
688 
689 err_stop_link:
690 	dw_pcie_stop_link(pci);
691 
692 err_remove_edma:
693 	dw_pcie_edma_remove(pci);
694 
695 err_free_msi:
696 	if (pp->has_msi_ctrl)
697 		dw_pcie_free_msi(pp);
698 
699 err_deinit_host:
700 	if (pp->ops->deinit)
701 		pp->ops->deinit(pp);
702 
703 err_free_ecam:
704 	if (pp->cfg)
705 		pci_ecam_free(pp->cfg);
706 
707 	return ret;
708 }
709 EXPORT_SYMBOL_GPL(dw_pcie_host_init);
710 
dw_pcie_host_deinit(struct dw_pcie_rp * pp)711 void dw_pcie_host_deinit(struct dw_pcie_rp *pp)
712 {
713 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
714 
715 	dwc_pcie_debugfs_deinit(pci);
716 
717 	pci_stop_root_bus(pp->bridge->bus);
718 	pci_remove_root_bus(pp->bridge->bus);
719 
720 	dw_pcie_stop_link(pci);
721 
722 	dw_pcie_edma_remove(pci);
723 
724 	if (pp->has_msi_ctrl)
725 		dw_pcie_free_msi(pp);
726 
727 	if (pp->ops->deinit)
728 		pp->ops->deinit(pp);
729 
730 	if (pp->cfg)
731 		pci_ecam_free(pp->cfg);
732 }
733 EXPORT_SYMBOL_GPL(dw_pcie_host_deinit);
734 
dw_pcie_other_conf_map_bus(struct pci_bus * bus,unsigned int devfn,int where)735 static void __iomem *dw_pcie_other_conf_map_bus(struct pci_bus *bus,
736 						unsigned int devfn, int where)
737 {
738 	struct dw_pcie_rp *pp = bus->sysdata;
739 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
740 	struct dw_pcie_ob_atu_cfg atu = { 0 };
741 	int type, ret;
742 	u32 busdev;
743 
744 	/*
745 	 * Checking whether the link is up here is a last line of defense
746 	 * against platforms that forward errors on the system bus as
747 	 * SError upon PCI configuration transactions issued when the link
748 	 * is down. This check is racy by definition and does not stop
749 	 * the system from triggering an SError if the link goes down
750 	 * after this check is performed.
751 	 */
752 	if (!dw_pcie_link_up(pci))
753 		return NULL;
754 
755 	busdev = PCIE_ATU_BUS(bus->number) | PCIE_ATU_DEV(PCI_SLOT(devfn)) |
756 		 PCIE_ATU_FUNC(PCI_FUNC(devfn));
757 
758 	if (pci_is_root_bus(bus->parent))
759 		type = PCIE_ATU_TYPE_CFG0;
760 	else
761 		type = PCIE_ATU_TYPE_CFG1;
762 
763 	atu.type = type;
764 	atu.parent_bus_addr = pp->cfg0_base - pci->parent_bus_offset;
765 	atu.pci_addr = busdev;
766 	atu.size = pp->cfg0_size;
767 
768 	ret = dw_pcie_prog_outbound_atu(pci, &atu);
769 	if (ret)
770 		return NULL;
771 
772 	return pp->va_cfg0_base + where;
773 }
774 
dw_pcie_rd_other_conf(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * val)775 static int dw_pcie_rd_other_conf(struct pci_bus *bus, unsigned int devfn,
776 				 int where, int size, u32 *val)
777 {
778 	struct dw_pcie_rp *pp = bus->sysdata;
779 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
780 	struct dw_pcie_ob_atu_cfg atu = { 0 };
781 	int ret;
782 
783 	ret = pci_generic_config_read(bus, devfn, where, size, val);
784 	if (ret != PCIBIOS_SUCCESSFUL)
785 		return ret;
786 
787 	if (pp->cfg0_io_shared) {
788 		atu.type = PCIE_ATU_TYPE_IO;
789 		atu.parent_bus_addr = pp->io_base - pci->parent_bus_offset;
790 		atu.pci_addr = pp->io_bus_addr;
791 		atu.size = pp->io_size;
792 
793 		ret = dw_pcie_prog_outbound_atu(pci, &atu);
794 		if (ret)
795 			return PCIBIOS_SET_FAILED;
796 	}
797 
798 	return PCIBIOS_SUCCESSFUL;
799 }
800 
dw_pcie_wr_other_conf(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 val)801 static int dw_pcie_wr_other_conf(struct pci_bus *bus, unsigned int devfn,
802 				 int where, int size, u32 val)
803 {
804 	struct dw_pcie_rp *pp = bus->sysdata;
805 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
806 	struct dw_pcie_ob_atu_cfg atu = { 0 };
807 	int ret;
808 
809 	ret = pci_generic_config_write(bus, devfn, where, size, val);
810 	if (ret != PCIBIOS_SUCCESSFUL)
811 		return ret;
812 
813 	if (pp->cfg0_io_shared) {
814 		atu.type = PCIE_ATU_TYPE_IO;
815 		atu.parent_bus_addr = pp->io_base - pci->parent_bus_offset;
816 		atu.pci_addr = pp->io_bus_addr;
817 		atu.size = pp->io_size;
818 
819 		ret = dw_pcie_prog_outbound_atu(pci, &atu);
820 		if (ret)
821 			return PCIBIOS_SET_FAILED;
822 	}
823 
824 	return PCIBIOS_SUCCESSFUL;
825 }
826 
827 static struct pci_ops dw_child_pcie_ops = {
828 	.map_bus = dw_pcie_other_conf_map_bus,
829 	.read = dw_pcie_rd_other_conf,
830 	.write = dw_pcie_wr_other_conf,
831 };
832 
dw_pcie_own_conf_map_bus(struct pci_bus * bus,unsigned int devfn,int where)833 void __iomem *dw_pcie_own_conf_map_bus(struct pci_bus *bus, unsigned int devfn, int where)
834 {
835 	struct dw_pcie_rp *pp = bus->sysdata;
836 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
837 
838 	if (PCI_SLOT(devfn) > 0)
839 		return NULL;
840 
841 	return pci->dbi_base + where;
842 }
843 EXPORT_SYMBOL_GPL(dw_pcie_own_conf_map_bus);
844 
845 static struct pci_ops dw_pcie_ops = {
846 	.map_bus = dw_pcie_own_conf_map_bus,
847 	.read = pci_generic_config_read,
848 	.write = pci_generic_config_write,
849 };
850 
dw_pcie_iatu_setup(struct dw_pcie_rp * pp)851 static int dw_pcie_iatu_setup(struct dw_pcie_rp *pp)
852 {
853 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
854 	struct dw_pcie_ob_atu_cfg atu = { 0 };
855 	struct resource_entry *entry;
856 	int i, ret;
857 
858 	/* Note the very first outbound ATU is used for CFG IOs */
859 	if (!pci->num_ob_windows) {
860 		dev_err(pci->dev, "No outbound iATU found\n");
861 		return -EINVAL;
862 	}
863 
864 	/*
865 	 * Ensure all out/inbound windows are disabled before proceeding with
866 	 * the MEM/IO (dma-)ranges setups.
867 	 */
868 	for (i = 0; i < pci->num_ob_windows; i++)
869 		dw_pcie_disable_atu(pci, PCIE_ATU_REGION_DIR_OB, i);
870 
871 	for (i = 0; i < pci->num_ib_windows; i++)
872 		dw_pcie_disable_atu(pci, PCIE_ATU_REGION_DIR_IB, i);
873 
874 	i = 0;
875 	resource_list_for_each_entry(entry, &pp->bridge->windows) {
876 		if (resource_type(entry->res) != IORESOURCE_MEM)
877 			continue;
878 
879 		if (pci->num_ob_windows <= ++i)
880 			break;
881 
882 		atu.index = i;
883 		atu.type = PCIE_ATU_TYPE_MEM;
884 		atu.parent_bus_addr = entry->res->start - pci->parent_bus_offset;
885 		atu.pci_addr = entry->res->start - entry->offset;
886 
887 		/* Adjust iATU size if MSG TLP region was allocated before */
888 		if (pp->msg_res && pp->msg_res->parent == entry->res)
889 			atu.size = resource_size(entry->res) -
890 					resource_size(pp->msg_res);
891 		else
892 			atu.size = resource_size(entry->res);
893 
894 		ret = dw_pcie_prog_outbound_atu(pci, &atu);
895 		if (ret) {
896 			dev_err(pci->dev, "Failed to set MEM range %pr\n",
897 				entry->res);
898 			return ret;
899 		}
900 	}
901 
902 	if (pp->io_size) {
903 		if (pci->num_ob_windows > ++i) {
904 			atu.index = i;
905 			atu.type = PCIE_ATU_TYPE_IO;
906 			atu.parent_bus_addr = pp->io_base - pci->parent_bus_offset;
907 			atu.pci_addr = pp->io_bus_addr;
908 			atu.size = pp->io_size;
909 
910 			ret = dw_pcie_prog_outbound_atu(pci, &atu);
911 			if (ret) {
912 				dev_err(pci->dev, "Failed to set IO range %pr\n",
913 					entry->res);
914 				return ret;
915 			}
916 		} else {
917 			pp->cfg0_io_shared = true;
918 		}
919 	}
920 
921 	if (pci->num_ob_windows <= i)
922 		dev_warn(pci->dev, "Ranges exceed outbound iATU size (%d)\n",
923 			 pci->num_ob_windows);
924 
925 	pp->msg_atu_index = i;
926 
927 	i = 0;
928 	resource_list_for_each_entry(entry, &pp->bridge->dma_ranges) {
929 		if (resource_type(entry->res) != IORESOURCE_MEM)
930 			continue;
931 
932 		if (pci->num_ib_windows <= i)
933 			break;
934 
935 		ret = dw_pcie_prog_inbound_atu(pci, i++, PCIE_ATU_TYPE_MEM,
936 					       entry->res->start,
937 					       entry->res->start - entry->offset,
938 					       resource_size(entry->res));
939 		if (ret) {
940 			dev_err(pci->dev, "Failed to set DMA range %pr\n",
941 				entry->res);
942 			return ret;
943 		}
944 	}
945 
946 	if (pci->num_ib_windows <= i)
947 		dev_warn(pci->dev, "Dma-ranges exceed inbound iATU size (%u)\n",
948 			 pci->num_ib_windows);
949 
950 	return 0;
951 }
952 
dw_pcie_program_presets(struct dw_pcie_rp * pp,enum pci_bus_speed speed)953 static void dw_pcie_program_presets(struct dw_pcie_rp *pp, enum pci_bus_speed speed)
954 {
955 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
956 	u8 lane_eq_offset, lane_reg_size, cap_id;
957 	u8 *presets;
958 	u32 cap;
959 	int i;
960 
961 	if (speed == PCIE_SPEED_8_0GT) {
962 		presets = (u8 *)pp->presets.eq_presets_8gts;
963 		lane_eq_offset =  PCI_SECPCI_LE_CTRL;
964 		cap_id = PCI_EXT_CAP_ID_SECPCI;
965 		/* For data rate of 8 GT/S each lane equalization control is 16bits wide*/
966 		lane_reg_size = 0x2;
967 	} else if (speed == PCIE_SPEED_16_0GT) {
968 		presets = pp->presets.eq_presets_Ngts[EQ_PRESET_TYPE_16GTS - 1];
969 		lane_eq_offset = PCI_PL_16GT_LE_CTRL;
970 		cap_id = PCI_EXT_CAP_ID_PL_16GT;
971 		lane_reg_size = 0x1;
972 	} else if (speed == PCIE_SPEED_32_0GT) {
973 		presets =  pp->presets.eq_presets_Ngts[EQ_PRESET_TYPE_32GTS - 1];
974 		lane_eq_offset = PCI_PL_32GT_LE_CTRL;
975 		cap_id = PCI_EXT_CAP_ID_PL_32GT;
976 		lane_reg_size = 0x1;
977 	} else if (speed == PCIE_SPEED_64_0GT) {
978 		presets =  pp->presets.eq_presets_Ngts[EQ_PRESET_TYPE_64GTS - 1];
979 		lane_eq_offset = PCI_PL_64GT_LE_CTRL;
980 		cap_id = PCI_EXT_CAP_ID_PL_64GT;
981 		lane_reg_size = 0x1;
982 	} else {
983 		return;
984 	}
985 
986 	if (presets[0] == PCI_EQ_RESV)
987 		return;
988 
989 	cap = dw_pcie_find_ext_capability(pci, cap_id);
990 	if (!cap)
991 		return;
992 
993 	/*
994 	 * Write preset values to the registers byte-by-byte for the given
995 	 * number of lanes and register size.
996 	 */
997 	for (i = 0; i < pci->num_lanes * lane_reg_size; i++)
998 		dw_pcie_writeb_dbi(pci, cap + lane_eq_offset + i, presets[i]);
999 }
1000 
dw_pcie_config_presets(struct dw_pcie_rp * pp)1001 static void dw_pcie_config_presets(struct dw_pcie_rp *pp)
1002 {
1003 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1004 	enum pci_bus_speed speed = pcie_link_speed[pci->max_link_speed];
1005 
1006 	/*
1007 	 * Lane equalization settings need to be applied for all data rates the
1008 	 * controller supports and for all supported lanes.
1009 	 */
1010 
1011 	if (speed >= PCIE_SPEED_8_0GT)
1012 		dw_pcie_program_presets(pp, PCIE_SPEED_8_0GT);
1013 
1014 	if (speed >= PCIE_SPEED_16_0GT)
1015 		dw_pcie_program_presets(pp, PCIE_SPEED_16_0GT);
1016 
1017 	if (speed >= PCIE_SPEED_32_0GT)
1018 		dw_pcie_program_presets(pp, PCIE_SPEED_32_0GT);
1019 
1020 	if (speed >= PCIE_SPEED_64_0GT)
1021 		dw_pcie_program_presets(pp, PCIE_SPEED_64_0GT);
1022 }
1023 
dw_pcie_setup_rc(struct dw_pcie_rp * pp)1024 int dw_pcie_setup_rc(struct dw_pcie_rp *pp)
1025 {
1026 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1027 	u32 val;
1028 	int ret;
1029 
1030 	/*
1031 	 * Enable DBI read-only registers for writing/updating configuration.
1032 	 * Write permission gets disabled towards the end of this function.
1033 	 */
1034 	dw_pcie_dbi_ro_wr_en(pci);
1035 
1036 	dw_pcie_setup(pci);
1037 
1038 	dw_pcie_msi_init(pp);
1039 
1040 	/* Setup RC BARs */
1041 	dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, 0x00000004);
1042 	dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_1, 0x00000000);
1043 
1044 	/* Setup interrupt pins */
1045 	val = dw_pcie_readl_dbi(pci, PCI_INTERRUPT_LINE);
1046 	val &= 0xffff00ff;
1047 	val |= 0x00000100;
1048 	dw_pcie_writel_dbi(pci, PCI_INTERRUPT_LINE, val);
1049 
1050 	/* Setup bus numbers */
1051 	val = dw_pcie_readl_dbi(pci, PCI_PRIMARY_BUS);
1052 	val &= 0xff000000;
1053 	val |= 0x00ff0100;
1054 	dw_pcie_writel_dbi(pci, PCI_PRIMARY_BUS, val);
1055 
1056 	/* Setup command register */
1057 	val = dw_pcie_readl_dbi(pci, PCI_COMMAND);
1058 	val &= 0xffff0000;
1059 	val |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY |
1060 		PCI_COMMAND_MASTER | PCI_COMMAND_SERR;
1061 	dw_pcie_writel_dbi(pci, PCI_COMMAND, val);
1062 
1063 	dw_pcie_config_presets(pp);
1064 	/*
1065 	 * If the platform provides its own child bus config accesses, it means
1066 	 * the platform uses its own address translation component rather than
1067 	 * ATU, so we should not program the ATU here.
1068 	 */
1069 	if (pp->bridge->child_ops == &dw_child_pcie_ops) {
1070 		ret = dw_pcie_iatu_setup(pp);
1071 		if (ret)
1072 			return ret;
1073 	}
1074 
1075 	dw_pcie_writel_dbi(pci, PCI_BASE_ADDRESS_0, 0);
1076 
1077 	/* Program correct class for RC */
1078 	dw_pcie_writew_dbi(pci, PCI_CLASS_DEVICE, PCI_CLASS_BRIDGE_PCI);
1079 
1080 	val = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
1081 	val |= PORT_LOGIC_SPEED_CHANGE;
1082 	dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, val);
1083 
1084 	dw_pcie_dbi_ro_wr_dis(pci);
1085 
1086 	return 0;
1087 }
1088 EXPORT_SYMBOL_GPL(dw_pcie_setup_rc);
1089 
dw_pcie_pme_turn_off(struct dw_pcie * pci)1090 static int dw_pcie_pme_turn_off(struct dw_pcie *pci)
1091 {
1092 	struct dw_pcie_ob_atu_cfg atu = { 0 };
1093 	void __iomem *mem;
1094 	int ret;
1095 
1096 	if (pci->num_ob_windows <= pci->pp.msg_atu_index)
1097 		return -ENOSPC;
1098 
1099 	if (!pci->pp.msg_res)
1100 		return -ENOSPC;
1101 
1102 	atu.code = PCIE_MSG_CODE_PME_TURN_OFF;
1103 	atu.routing = PCIE_MSG_TYPE_R_BC;
1104 	atu.type = PCIE_ATU_TYPE_MSG;
1105 	atu.size = resource_size(pci->pp.msg_res);
1106 	atu.index = pci->pp.msg_atu_index;
1107 
1108 	atu.parent_bus_addr = pci->pp.msg_res->start - pci->parent_bus_offset;
1109 
1110 	ret = dw_pcie_prog_outbound_atu(pci, &atu);
1111 	if (ret)
1112 		return ret;
1113 
1114 	mem = ioremap(pci->pp.msg_res->start, pci->region_align);
1115 	if (!mem)
1116 		return -ENOMEM;
1117 
1118 	/* A dummy write is converted to a Msg TLP */
1119 	writel(0, mem);
1120 
1121 	iounmap(mem);
1122 
1123 	return 0;
1124 }
1125 
dw_pcie_suspend_noirq(struct dw_pcie * pci)1126 int dw_pcie_suspend_noirq(struct dw_pcie *pci)
1127 {
1128 	u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
1129 	u32 val;
1130 	int ret;
1131 
1132 	/*
1133 	 * If L1SS is supported, then do not put the link into L2 as some
1134 	 * devices such as NVMe expect low resume latency.
1135 	 */
1136 	if (dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKCTL) & PCI_EXP_LNKCTL_ASPM_L1)
1137 		return 0;
1138 
1139 	if (pci->pp.ops->pme_turn_off) {
1140 		pci->pp.ops->pme_turn_off(&pci->pp);
1141 	} else {
1142 		ret = dw_pcie_pme_turn_off(pci);
1143 		if (ret)
1144 			return ret;
1145 	}
1146 
1147 	ret = read_poll_timeout(dw_pcie_get_ltssm, val,
1148 				val == DW_PCIE_LTSSM_L2_IDLE ||
1149 				val <= DW_PCIE_LTSSM_DETECT_WAIT,
1150 				PCIE_PME_TO_L2_TIMEOUT_US/10,
1151 				PCIE_PME_TO_L2_TIMEOUT_US, false, pci);
1152 	if (ret) {
1153 		/* Only log message when LTSSM isn't in DETECT or POLL */
1154 		dev_err(pci->dev, "Timeout waiting for L2 entry! LTSSM: 0x%x\n", val);
1155 		return ret;
1156 	}
1157 
1158 	/*
1159 	 * Per PCIe r6.0, sec 5.3.3.2.1, software should wait at least
1160 	 * 100ns after L2/L3 Ready before turning off refclock and
1161 	 * main power. This is harmless when no endpoint is connected.
1162 	 */
1163 	udelay(1);
1164 
1165 	dw_pcie_stop_link(pci);
1166 	if (pci->pp.ops->deinit)
1167 		pci->pp.ops->deinit(&pci->pp);
1168 
1169 	pci->suspended = true;
1170 
1171 	return ret;
1172 }
1173 EXPORT_SYMBOL_GPL(dw_pcie_suspend_noirq);
1174 
dw_pcie_resume_noirq(struct dw_pcie * pci)1175 int dw_pcie_resume_noirq(struct dw_pcie *pci)
1176 {
1177 	int ret;
1178 
1179 	if (!pci->suspended)
1180 		return 0;
1181 
1182 	pci->suspended = false;
1183 
1184 	if (pci->pp.ops->init) {
1185 		ret = pci->pp.ops->init(&pci->pp);
1186 		if (ret) {
1187 			dev_err(pci->dev, "Host init failed: %d\n", ret);
1188 			return ret;
1189 		}
1190 	}
1191 
1192 	dw_pcie_setup_rc(&pci->pp);
1193 
1194 	ret = dw_pcie_start_link(pci);
1195 	if (ret)
1196 		return ret;
1197 
1198 	ret = dw_pcie_wait_for_link(pci);
1199 	if (ret)
1200 		return ret;
1201 
1202 	return ret;
1203 }
1204 EXPORT_SYMBOL_GPL(dw_pcie_resume_noirq);
1205