1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * PCIe driver for Renesas R-Car SoCs
4  *  Copyright (C) 2014-2020 Renesas Electronics Europe Ltd
5  *
6  * Based on:
7  *  arch/sh/drivers/pci/pcie-sh7786.c
8  *  arch/sh/drivers/pci/ops-sh7786.c
9  *  Copyright (C) 2009 - 2011  Paul Mundt
10  *
11  * Author: Phil Edworthy <phil.edworthy@renesas.com>
12  */
13 
14 #include <linux/bitops.h>
15 #include <linux/clk.h>
16 #include <linux/delay.h>
17 #include <linux/interrupt.h>
18 #include <linux/irq.h>
19 #include <linux/irqdomain.h>
20 #include <linux/kernel.h>
21 #include <linux/init.h>
22 #include <linux/msi.h>
23 #include <linux/of_address.h>
24 #include <linux/of_irq.h>
25 #include <linux/of_pci.h>
26 #include <linux/of_platform.h>
27 #include <linux/pci.h>
28 #include <linux/phy/phy.h>
29 #include <linux/platform_device.h>
30 #include <linux/pm_runtime.h>
31 #include <linux/slab.h>
32 
33 #include "pcie-rcar.h"
34 
35 struct rcar_msi {
36 	DECLARE_BITMAP(used, INT_PCI_MSI_NR);
37 	struct irq_domain *domain;
38 	struct msi_controller chip;
39 	unsigned long pages;
40 	struct mutex lock;
41 	int irq1;
42 	int irq2;
43 };
44 
45 static inline struct rcar_msi *to_rcar_msi(struct msi_controller *chip)
46 {
47 	return container_of(chip, struct rcar_msi, chip);
48 }
49 
50 /* Structure representing the PCIe interface */
51 struct rcar_pcie_host {
52 	struct rcar_pcie	pcie;
53 	struct device		*dev;
54 	struct phy		*phy;
55 	void __iomem		*base;
56 	struct clk		*bus_clk;
57 	struct			rcar_msi msi;
58 	int			(*phy_init_fn)(struct rcar_pcie_host *host);
59 };
60 
61 static u32 rcar_read_conf(struct rcar_pcie *pcie, int where)
62 {
63 	unsigned int shift = BITS_PER_BYTE * (where & 3);
64 	u32 val = rcar_pci_read_reg(pcie, where & ~3);
65 
66 	return val >> shift;
67 }
68 
69 /* Serialization is provided by 'pci_lock' in drivers/pci/access.c */
70 static int rcar_pcie_config_access(struct rcar_pcie_host *host,
71 		unsigned char access_type, struct pci_bus *bus,
72 		unsigned int devfn, int where, u32 *data)
73 {
74 	struct rcar_pcie *pcie = &host->pcie;
75 	unsigned int dev, func, reg, index;
76 
77 	dev = PCI_SLOT(devfn);
78 	func = PCI_FUNC(devfn);
79 	reg = where & ~3;
80 	index = reg / 4;
81 
82 	/*
83 	 * While each channel has its own memory-mapped extended config
84 	 * space, it's generally only accessible when in endpoint mode.
85 	 * When in root complex mode, the controller is unable to target
86 	 * itself with either type 0 or type 1 accesses, and indeed, any
87 	 * controller initiated target transfer to its own config space
88 	 * result in a completer abort.
89 	 *
90 	 * Each channel effectively only supports a single device, but as
91 	 * the same channel <-> device access works for any PCI_SLOT()
92 	 * value, we cheat a bit here and bind the controller's config
93 	 * space to devfn 0 in order to enable self-enumeration. In this
94 	 * case the regular ECAR/ECDR path is sidelined and the mangled
95 	 * config access itself is initiated as an internal bus transaction.
96 	 */
97 	if (pci_is_root_bus(bus)) {
98 		if (dev != 0)
99 			return PCIBIOS_DEVICE_NOT_FOUND;
100 
101 		if (access_type == RCAR_PCI_ACCESS_READ)
102 			*data = rcar_pci_read_reg(pcie, PCICONF(index));
103 		else
104 			rcar_pci_write_reg(pcie, *data, PCICONF(index));
105 
106 		return PCIBIOS_SUCCESSFUL;
107 	}
108 
109 	/* Clear errors */
110 	rcar_pci_write_reg(pcie, rcar_pci_read_reg(pcie, PCIEERRFR), PCIEERRFR);
111 
112 	/* Set the PIO address */
113 	rcar_pci_write_reg(pcie, PCIE_CONF_BUS(bus->number) |
114 		PCIE_CONF_DEV(dev) | PCIE_CONF_FUNC(func) | reg, PCIECAR);
115 
116 	/* Enable the configuration access */
117 	if (pci_is_root_bus(bus->parent))
118 		rcar_pci_write_reg(pcie, CONFIG_SEND_ENABLE | TYPE0, PCIECCTLR);
119 	else
120 		rcar_pci_write_reg(pcie, CONFIG_SEND_ENABLE | TYPE1, PCIECCTLR);
121 
122 	/* Check for errors */
123 	if (rcar_pci_read_reg(pcie, PCIEERRFR) & UNSUPPORTED_REQUEST)
124 		return PCIBIOS_DEVICE_NOT_FOUND;
125 
126 	/* Check for master and target aborts */
127 	if (rcar_read_conf(pcie, RCONF(PCI_STATUS)) &
128 		(PCI_STATUS_REC_MASTER_ABORT | PCI_STATUS_REC_TARGET_ABORT))
129 		return PCIBIOS_DEVICE_NOT_FOUND;
130 
131 	if (access_type == RCAR_PCI_ACCESS_READ)
132 		*data = rcar_pci_read_reg(pcie, PCIECDR);
133 	else
134 		rcar_pci_write_reg(pcie, *data, PCIECDR);
135 
136 	/* Disable the configuration access */
137 	rcar_pci_write_reg(pcie, 0, PCIECCTLR);
138 
139 	return PCIBIOS_SUCCESSFUL;
140 }
141 
142 static int rcar_pcie_read_conf(struct pci_bus *bus, unsigned int devfn,
143 			       int where, int size, u32 *val)
144 {
145 	struct rcar_pcie_host *host = bus->sysdata;
146 	int ret;
147 
148 	ret = rcar_pcie_config_access(host, RCAR_PCI_ACCESS_READ,
149 				      bus, devfn, where, val);
150 	if (ret != PCIBIOS_SUCCESSFUL) {
151 		*val = 0xffffffff;
152 		return ret;
153 	}
154 
155 	if (size == 1)
156 		*val = (*val >> (BITS_PER_BYTE * (where & 3))) & 0xff;
157 	else if (size == 2)
158 		*val = (*val >> (BITS_PER_BYTE * (where & 2))) & 0xffff;
159 
160 	dev_dbg(&bus->dev, "pcie-config-read: bus=%3d devfn=0x%04x where=0x%04x size=%d val=0x%08x\n",
161 		bus->number, devfn, where, size, *val);
162 
163 	return ret;
164 }
165 
166 /* Serialization is provided by 'pci_lock' in drivers/pci/access.c */
167 static int rcar_pcie_write_conf(struct pci_bus *bus, unsigned int devfn,
168 				int where, int size, u32 val)
169 {
170 	struct rcar_pcie_host *host = bus->sysdata;
171 	unsigned int shift;
172 	u32 data;
173 	int ret;
174 
175 	ret = rcar_pcie_config_access(host, RCAR_PCI_ACCESS_READ,
176 				      bus, devfn, where, &data);
177 	if (ret != PCIBIOS_SUCCESSFUL)
178 		return ret;
179 
180 	dev_dbg(&bus->dev, "pcie-config-write: bus=%3d devfn=0x%04x where=0x%04x size=%d val=0x%08x\n",
181 		bus->number, devfn, where, size, val);
182 
183 	if (size == 1) {
184 		shift = BITS_PER_BYTE * (where & 3);
185 		data &= ~(0xff << shift);
186 		data |= ((val & 0xff) << shift);
187 	} else if (size == 2) {
188 		shift = BITS_PER_BYTE * (where & 2);
189 		data &= ~(0xffff << shift);
190 		data |= ((val & 0xffff) << shift);
191 	} else
192 		data = val;
193 
194 	ret = rcar_pcie_config_access(host, RCAR_PCI_ACCESS_WRITE,
195 				      bus, devfn, where, &data);
196 
197 	return ret;
198 }
199 
200 static struct pci_ops rcar_pcie_ops = {
201 	.read	= rcar_pcie_read_conf,
202 	.write	= rcar_pcie_write_conf,
203 };
204 
205 static void rcar_pcie_force_speedup(struct rcar_pcie *pcie)
206 {
207 	struct device *dev = pcie->dev;
208 	unsigned int timeout = 1000;
209 	u32 macsr;
210 
211 	if ((rcar_pci_read_reg(pcie, MACS2R) & LINK_SPEED) != LINK_SPEED_5_0GTS)
212 		return;
213 
214 	if (rcar_pci_read_reg(pcie, MACCTLR) & SPEED_CHANGE) {
215 		dev_err(dev, "Speed change already in progress\n");
216 		return;
217 	}
218 
219 	macsr = rcar_pci_read_reg(pcie, MACSR);
220 	if ((macsr & LINK_SPEED) == LINK_SPEED_5_0GTS)
221 		goto done;
222 
223 	/* Set target link speed to 5.0 GT/s */
224 	rcar_rmw32(pcie, EXPCAP(12), PCI_EXP_LNKSTA_CLS,
225 		   PCI_EXP_LNKSTA_CLS_5_0GB);
226 
227 	/* Set speed change reason as intentional factor */
228 	rcar_rmw32(pcie, MACCGSPSETR, SPCNGRSN, 0);
229 
230 	/* Clear SPCHGFIN, SPCHGSUC, and SPCHGFAIL */
231 	if (macsr & (SPCHGFIN | SPCHGSUC | SPCHGFAIL))
232 		rcar_pci_write_reg(pcie, macsr, MACSR);
233 
234 	/* Start link speed change */
235 	rcar_rmw32(pcie, MACCTLR, SPEED_CHANGE, SPEED_CHANGE);
236 
237 	while (timeout--) {
238 		macsr = rcar_pci_read_reg(pcie, MACSR);
239 		if (macsr & SPCHGFIN) {
240 			/* Clear the interrupt bits */
241 			rcar_pci_write_reg(pcie, macsr, MACSR);
242 
243 			if (macsr & SPCHGFAIL)
244 				dev_err(dev, "Speed change failed\n");
245 
246 			goto done;
247 		}
248 
249 		msleep(1);
250 	}
251 
252 	dev_err(dev, "Speed change timed out\n");
253 
254 done:
255 	dev_info(dev, "Current link speed is %s GT/s\n",
256 		 (macsr & LINK_SPEED) == LINK_SPEED_5_0GTS ? "5" : "2.5");
257 }
258 
259 static void rcar_pcie_hw_enable(struct rcar_pcie_host *host)
260 {
261 	struct rcar_pcie *pcie = &host->pcie;
262 	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(host);
263 	struct resource_entry *win;
264 	LIST_HEAD(res);
265 	int i = 0;
266 
267 	/* Try setting 5 GT/s link speed */
268 	rcar_pcie_force_speedup(pcie);
269 
270 	/* Setup PCI resources */
271 	resource_list_for_each_entry(win, &bridge->windows) {
272 		struct resource *res = win->res;
273 
274 		if (!res->flags)
275 			continue;
276 
277 		switch (resource_type(res)) {
278 		case IORESOURCE_IO:
279 		case IORESOURCE_MEM:
280 			rcar_pcie_set_outbound(pcie, i, win);
281 			i++;
282 			break;
283 		}
284 	}
285 }
286 
287 static int rcar_pcie_enable(struct rcar_pcie_host *host)
288 {
289 	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(host);
290 
291 	rcar_pcie_hw_enable(host);
292 
293 	pci_add_flags(PCI_REASSIGN_ALL_BUS);
294 
295 	bridge->sysdata = host;
296 	bridge->ops = &rcar_pcie_ops;
297 	if (IS_ENABLED(CONFIG_PCI_MSI))
298 		bridge->msi = &host->msi.chip;
299 
300 	return pci_host_probe(bridge);
301 }
302 
303 static int phy_wait_for_ack(struct rcar_pcie *pcie)
304 {
305 	struct device *dev = pcie->dev;
306 	unsigned int timeout = 100;
307 
308 	while (timeout--) {
309 		if (rcar_pci_read_reg(pcie, H1_PCIEPHYADRR) & PHY_ACK)
310 			return 0;
311 
312 		udelay(100);
313 	}
314 
315 	dev_err(dev, "Access to PCIe phy timed out\n");
316 
317 	return -ETIMEDOUT;
318 }
319 
320 static void phy_write_reg(struct rcar_pcie *pcie,
321 			  unsigned int rate, u32 addr,
322 			  unsigned int lane, u32 data)
323 {
324 	u32 phyaddr;
325 
326 	phyaddr = WRITE_CMD |
327 		((rate & 1) << RATE_POS) |
328 		((lane & 0xf) << LANE_POS) |
329 		((addr & 0xff) << ADR_POS);
330 
331 	/* Set write data */
332 	rcar_pci_write_reg(pcie, data, H1_PCIEPHYDOUTR);
333 	rcar_pci_write_reg(pcie, phyaddr, H1_PCIEPHYADRR);
334 
335 	/* Ignore errors as they will be dealt with if the data link is down */
336 	phy_wait_for_ack(pcie);
337 
338 	/* Clear command */
339 	rcar_pci_write_reg(pcie, 0, H1_PCIEPHYDOUTR);
340 	rcar_pci_write_reg(pcie, 0, H1_PCIEPHYADRR);
341 
342 	/* Ignore errors as they will be dealt with if the data link is down */
343 	phy_wait_for_ack(pcie);
344 }
345 
346 static int rcar_pcie_hw_init(struct rcar_pcie *pcie)
347 {
348 	int err;
349 
350 	/* Begin initialization */
351 	rcar_pci_write_reg(pcie, 0, PCIETCTLR);
352 
353 	/* Set mode */
354 	rcar_pci_write_reg(pcie, 1, PCIEMSR);
355 
356 	err = rcar_pcie_wait_for_phyrdy(pcie);
357 	if (err)
358 		return err;
359 
360 	/*
361 	 * Initial header for port config space is type 1, set the device
362 	 * class to match. Hardware takes care of propagating the IDSETR
363 	 * settings, so there is no need to bother with a quirk.
364 	 */
365 	rcar_pci_write_reg(pcie, PCI_CLASS_BRIDGE_PCI << 16, IDSETR1);
366 
367 	/*
368 	 * Setup Secondary Bus Number & Subordinate Bus Number, even though
369 	 * they aren't used, to avoid bridge being detected as broken.
370 	 */
371 	rcar_rmw32(pcie, RCONF(PCI_SECONDARY_BUS), 0xff, 1);
372 	rcar_rmw32(pcie, RCONF(PCI_SUBORDINATE_BUS), 0xff, 1);
373 
374 	/* Initialize default capabilities. */
375 	rcar_rmw32(pcie, REXPCAP(0), 0xff, PCI_CAP_ID_EXP);
376 	rcar_rmw32(pcie, REXPCAP(PCI_EXP_FLAGS),
377 		PCI_EXP_FLAGS_TYPE, PCI_EXP_TYPE_ROOT_PORT << 4);
378 	rcar_rmw32(pcie, RCONF(PCI_HEADER_TYPE), 0x7f,
379 		PCI_HEADER_TYPE_BRIDGE);
380 
381 	/* Enable data link layer active state reporting */
382 	rcar_rmw32(pcie, REXPCAP(PCI_EXP_LNKCAP), PCI_EXP_LNKCAP_DLLLARC,
383 		PCI_EXP_LNKCAP_DLLLARC);
384 
385 	/* Write out the physical slot number = 0 */
386 	rcar_rmw32(pcie, REXPCAP(PCI_EXP_SLTCAP), PCI_EXP_SLTCAP_PSN, 0);
387 
388 	/* Set the completion timer timeout to the maximum 50ms. */
389 	rcar_rmw32(pcie, TLCTLR + 1, 0x3f, 50);
390 
391 	/* Terminate list of capabilities (Next Capability Offset=0) */
392 	rcar_rmw32(pcie, RVCCAP(0), 0xfff00000, 0);
393 
394 	/* Enable MSI */
395 	if (IS_ENABLED(CONFIG_PCI_MSI))
396 		rcar_pci_write_reg(pcie, 0x801f0000, PCIEMSITXR);
397 
398 	rcar_pci_write_reg(pcie, MACCTLR_INIT_VAL, MACCTLR);
399 
400 	/* Finish initialization - establish a PCI Express link */
401 	rcar_pci_write_reg(pcie, CFINIT, PCIETCTLR);
402 
403 	/* This will timeout if we don't have a link. */
404 	err = rcar_pcie_wait_for_dl(pcie);
405 	if (err)
406 		return err;
407 
408 	/* Enable INTx interrupts */
409 	rcar_rmw32(pcie, PCIEINTXR, 0, 0xF << 8);
410 
411 	wmb();
412 
413 	return 0;
414 }
415 
416 static int rcar_pcie_phy_init_h1(struct rcar_pcie_host *host)
417 {
418 	struct rcar_pcie *pcie = &host->pcie;
419 
420 	/* Initialize the phy */
421 	phy_write_reg(pcie, 0, 0x42, 0x1, 0x0EC34191);
422 	phy_write_reg(pcie, 1, 0x42, 0x1, 0x0EC34180);
423 	phy_write_reg(pcie, 0, 0x43, 0x1, 0x00210188);
424 	phy_write_reg(pcie, 1, 0x43, 0x1, 0x00210188);
425 	phy_write_reg(pcie, 0, 0x44, 0x1, 0x015C0014);
426 	phy_write_reg(pcie, 1, 0x44, 0x1, 0x015C0014);
427 	phy_write_reg(pcie, 1, 0x4C, 0x1, 0x786174A0);
428 	phy_write_reg(pcie, 1, 0x4D, 0x1, 0x048000BB);
429 	phy_write_reg(pcie, 0, 0x51, 0x1, 0x079EC062);
430 	phy_write_reg(pcie, 0, 0x52, 0x1, 0x20000000);
431 	phy_write_reg(pcie, 1, 0x52, 0x1, 0x20000000);
432 	phy_write_reg(pcie, 1, 0x56, 0x1, 0x00003806);
433 
434 	phy_write_reg(pcie, 0, 0x60, 0x1, 0x004B03A5);
435 	phy_write_reg(pcie, 0, 0x64, 0x1, 0x3F0F1F0F);
436 	phy_write_reg(pcie, 0, 0x66, 0x1, 0x00008000);
437 
438 	return 0;
439 }
440 
441 static int rcar_pcie_phy_init_gen2(struct rcar_pcie_host *host)
442 {
443 	struct rcar_pcie *pcie = &host->pcie;
444 
445 	/*
446 	 * These settings come from the R-Car Series, 2nd Generation User's
447 	 * Manual, section 50.3.1 (2) Initialization of the physical layer.
448 	 */
449 	rcar_pci_write_reg(pcie, 0x000f0030, GEN2_PCIEPHYADDR);
450 	rcar_pci_write_reg(pcie, 0x00381203, GEN2_PCIEPHYDATA);
451 	rcar_pci_write_reg(pcie, 0x00000001, GEN2_PCIEPHYCTRL);
452 	rcar_pci_write_reg(pcie, 0x00000006, GEN2_PCIEPHYCTRL);
453 
454 	rcar_pci_write_reg(pcie, 0x000f0054, GEN2_PCIEPHYADDR);
455 	/* The following value is for DC connection, no termination resistor */
456 	rcar_pci_write_reg(pcie, 0x13802007, GEN2_PCIEPHYDATA);
457 	rcar_pci_write_reg(pcie, 0x00000001, GEN2_PCIEPHYCTRL);
458 	rcar_pci_write_reg(pcie, 0x00000006, GEN2_PCIEPHYCTRL);
459 
460 	return 0;
461 }
462 
463 static int rcar_pcie_phy_init_gen3(struct rcar_pcie_host *host)
464 {
465 	int err;
466 
467 	err = phy_init(host->phy);
468 	if (err)
469 		return err;
470 
471 	err = phy_power_on(host->phy);
472 	if (err)
473 		phy_exit(host->phy);
474 
475 	return err;
476 }
477 
478 static int rcar_msi_alloc(struct rcar_msi *chip)
479 {
480 	int msi;
481 
482 	mutex_lock(&chip->lock);
483 
484 	msi = find_first_zero_bit(chip->used, INT_PCI_MSI_NR);
485 	if (msi < INT_PCI_MSI_NR)
486 		set_bit(msi, chip->used);
487 	else
488 		msi = -ENOSPC;
489 
490 	mutex_unlock(&chip->lock);
491 
492 	return msi;
493 }
494 
495 static int rcar_msi_alloc_region(struct rcar_msi *chip, int no_irqs)
496 {
497 	int msi;
498 
499 	mutex_lock(&chip->lock);
500 	msi = bitmap_find_free_region(chip->used, INT_PCI_MSI_NR,
501 				      order_base_2(no_irqs));
502 	mutex_unlock(&chip->lock);
503 
504 	return msi;
505 }
506 
507 static void rcar_msi_free(struct rcar_msi *chip, unsigned long irq)
508 {
509 	mutex_lock(&chip->lock);
510 	clear_bit(irq, chip->used);
511 	mutex_unlock(&chip->lock);
512 }
513 
514 static irqreturn_t rcar_pcie_msi_irq(int irq, void *data)
515 {
516 	struct rcar_pcie_host *host = data;
517 	struct rcar_pcie *pcie = &host->pcie;
518 	struct rcar_msi *msi = &host->msi;
519 	struct device *dev = pcie->dev;
520 	unsigned long reg;
521 
522 	reg = rcar_pci_read_reg(pcie, PCIEMSIFR);
523 
524 	/* MSI & INTx share an interrupt - we only handle MSI here */
525 	if (!reg)
526 		return IRQ_NONE;
527 
528 	while (reg) {
529 		unsigned int index = find_first_bit(&reg, 32);
530 		unsigned int msi_irq;
531 
532 		/* clear the interrupt */
533 		rcar_pci_write_reg(pcie, 1 << index, PCIEMSIFR);
534 
535 		msi_irq = irq_find_mapping(msi->domain, index);
536 		if (msi_irq) {
537 			if (test_bit(index, msi->used))
538 				generic_handle_irq(msi_irq);
539 			else
540 				dev_info(dev, "unhandled MSI\n");
541 		} else {
542 			/* Unknown MSI, just clear it */
543 			dev_dbg(dev, "unexpected MSI\n");
544 		}
545 
546 		/* see if there's any more pending in this vector */
547 		reg = rcar_pci_read_reg(pcie, PCIEMSIFR);
548 	}
549 
550 	return IRQ_HANDLED;
551 }
552 
553 static int rcar_msi_setup_irq(struct msi_controller *chip, struct pci_dev *pdev,
554 			      struct msi_desc *desc)
555 {
556 	struct rcar_msi *msi = to_rcar_msi(chip);
557 	struct rcar_pcie_host *host = container_of(chip, struct rcar_pcie_host,
558 						   msi.chip);
559 	struct rcar_pcie *pcie = &host->pcie;
560 	struct msi_msg msg;
561 	unsigned int irq;
562 	int hwirq;
563 
564 	hwirq = rcar_msi_alloc(msi);
565 	if (hwirq < 0)
566 		return hwirq;
567 
568 	irq = irq_find_mapping(msi->domain, hwirq);
569 	if (!irq) {
570 		rcar_msi_free(msi, hwirq);
571 		return -EINVAL;
572 	}
573 
574 	irq_set_msi_desc(irq, desc);
575 
576 	msg.address_lo = rcar_pci_read_reg(pcie, PCIEMSIALR) & ~MSIFE;
577 	msg.address_hi = rcar_pci_read_reg(pcie, PCIEMSIAUR);
578 	msg.data = hwirq;
579 
580 	pci_write_msi_msg(irq, &msg);
581 
582 	return 0;
583 }
584 
585 static int rcar_msi_setup_irqs(struct msi_controller *chip,
586 			       struct pci_dev *pdev, int nvec, int type)
587 {
588 	struct rcar_msi *msi = to_rcar_msi(chip);
589 	struct rcar_pcie_host *host = container_of(chip, struct rcar_pcie_host,
590 						   msi.chip);
591 	struct rcar_pcie *pcie = &host->pcie;
592 	struct msi_desc *desc;
593 	struct msi_msg msg;
594 	unsigned int irq;
595 	int hwirq;
596 	int i;
597 
598 	/* MSI-X interrupts are not supported */
599 	if (type == PCI_CAP_ID_MSIX)
600 		return -EINVAL;
601 
602 	WARN_ON(!list_is_singular(&pdev->dev.msi_list));
603 	desc = list_entry(pdev->dev.msi_list.next, struct msi_desc, list);
604 
605 	hwirq = rcar_msi_alloc_region(msi, nvec);
606 	if (hwirq < 0)
607 		return -ENOSPC;
608 
609 	irq = irq_find_mapping(msi->domain, hwirq);
610 	if (!irq)
611 		return -ENOSPC;
612 
613 	for (i = 0; i < nvec; i++) {
614 		/*
615 		 * irq_create_mapping() called from rcar_pcie_probe() pre-
616 		 * allocates descs,  so there is no need to allocate descs here.
617 		 * We can therefore assume that if irq_find_mapping() above
618 		 * returns non-zero, then the descs are also successfully
619 		 * allocated.
620 		 */
621 		if (irq_set_msi_desc_off(irq, i, desc)) {
622 			/* TODO: clear */
623 			return -EINVAL;
624 		}
625 	}
626 
627 	desc->nvec_used = nvec;
628 	desc->msi_attrib.multiple = order_base_2(nvec);
629 
630 	msg.address_lo = rcar_pci_read_reg(pcie, PCIEMSIALR) & ~MSIFE;
631 	msg.address_hi = rcar_pci_read_reg(pcie, PCIEMSIAUR);
632 	msg.data = hwirq;
633 
634 	pci_write_msi_msg(irq, &msg);
635 
636 	return 0;
637 }
638 
639 static void rcar_msi_teardown_irq(struct msi_controller *chip, unsigned int irq)
640 {
641 	struct rcar_msi *msi = to_rcar_msi(chip);
642 	struct irq_data *d = irq_get_irq_data(irq);
643 
644 	rcar_msi_free(msi, d->hwirq);
645 }
646 
647 static struct irq_chip rcar_msi_irq_chip = {
648 	.name = "R-Car PCIe MSI",
649 	.irq_enable = pci_msi_unmask_irq,
650 	.irq_disable = pci_msi_mask_irq,
651 	.irq_mask = pci_msi_mask_irq,
652 	.irq_unmask = pci_msi_unmask_irq,
653 };
654 
655 static int rcar_msi_map(struct irq_domain *domain, unsigned int irq,
656 			irq_hw_number_t hwirq)
657 {
658 	irq_set_chip_and_handler(irq, &rcar_msi_irq_chip, handle_simple_irq);
659 	irq_set_chip_data(irq, domain->host_data);
660 
661 	return 0;
662 }
663 
664 static const struct irq_domain_ops msi_domain_ops = {
665 	.map = rcar_msi_map,
666 };
667 
668 static void rcar_pcie_unmap_msi(struct rcar_pcie_host *host)
669 {
670 	struct rcar_msi *msi = &host->msi;
671 	int i, irq;
672 
673 	for (i = 0; i < INT_PCI_MSI_NR; i++) {
674 		irq = irq_find_mapping(msi->domain, i);
675 		if (irq > 0)
676 			irq_dispose_mapping(irq);
677 	}
678 
679 	irq_domain_remove(msi->domain);
680 }
681 
682 static void rcar_pcie_hw_enable_msi(struct rcar_pcie_host *host)
683 {
684 	struct rcar_pcie *pcie = &host->pcie;
685 	struct rcar_msi *msi = &host->msi;
686 	unsigned long base;
687 
688 	/* setup MSI data target */
689 	base = virt_to_phys((void *)msi->pages);
690 
691 	rcar_pci_write_reg(pcie, lower_32_bits(base) | MSIFE, PCIEMSIALR);
692 	rcar_pci_write_reg(pcie, upper_32_bits(base), PCIEMSIAUR);
693 
694 	/* enable all MSI interrupts */
695 	rcar_pci_write_reg(pcie, 0xffffffff, PCIEMSIIER);
696 }
697 
698 static int rcar_pcie_enable_msi(struct rcar_pcie_host *host)
699 {
700 	struct rcar_pcie *pcie = &host->pcie;
701 	struct device *dev = pcie->dev;
702 	struct rcar_msi *msi = &host->msi;
703 	int err, i;
704 
705 	mutex_init(&msi->lock);
706 
707 	msi->chip.dev = dev;
708 	msi->chip.setup_irq = rcar_msi_setup_irq;
709 	msi->chip.setup_irqs = rcar_msi_setup_irqs;
710 	msi->chip.teardown_irq = rcar_msi_teardown_irq;
711 
712 	msi->domain = irq_domain_add_linear(dev->of_node, INT_PCI_MSI_NR,
713 					    &msi_domain_ops, &msi->chip);
714 	if (!msi->domain) {
715 		dev_err(dev, "failed to create IRQ domain\n");
716 		return -ENOMEM;
717 	}
718 
719 	for (i = 0; i < INT_PCI_MSI_NR; i++)
720 		irq_create_mapping(msi->domain, i);
721 
722 	/* Two irqs are for MSI, but they are also used for non-MSI irqs */
723 	err = devm_request_irq(dev, msi->irq1, rcar_pcie_msi_irq,
724 			       IRQF_SHARED | IRQF_NO_THREAD,
725 			       rcar_msi_irq_chip.name, host);
726 	if (err < 0) {
727 		dev_err(dev, "failed to request IRQ: %d\n", err);
728 		goto err;
729 	}
730 
731 	err = devm_request_irq(dev, msi->irq2, rcar_pcie_msi_irq,
732 			       IRQF_SHARED | IRQF_NO_THREAD,
733 			       rcar_msi_irq_chip.name, host);
734 	if (err < 0) {
735 		dev_err(dev, "failed to request IRQ: %d\n", err);
736 		goto err;
737 	}
738 
739 	/* setup MSI data target */
740 	msi->pages = __get_free_pages(GFP_KERNEL, 0);
741 	rcar_pcie_hw_enable_msi(host);
742 
743 	return 0;
744 
745 err:
746 	rcar_pcie_unmap_msi(host);
747 	return err;
748 }
749 
750 static void rcar_pcie_teardown_msi(struct rcar_pcie_host *host)
751 {
752 	struct rcar_pcie *pcie = &host->pcie;
753 	struct rcar_msi *msi = &host->msi;
754 
755 	/* Disable all MSI interrupts */
756 	rcar_pci_write_reg(pcie, 0, PCIEMSIIER);
757 
758 	/* Disable address decoding of the MSI interrupt, MSIFE */
759 	rcar_pci_write_reg(pcie, 0, PCIEMSIALR);
760 
761 	free_pages(msi->pages, 0);
762 
763 	rcar_pcie_unmap_msi(host);
764 }
765 
766 static int rcar_pcie_get_resources(struct rcar_pcie_host *host)
767 {
768 	struct rcar_pcie *pcie = &host->pcie;
769 	struct device *dev = pcie->dev;
770 	struct resource res;
771 	int err, i;
772 
773 	host->phy = devm_phy_optional_get(dev, "pcie");
774 	if (IS_ERR(host->phy))
775 		return PTR_ERR(host->phy);
776 
777 	err = of_address_to_resource(dev->of_node, 0, &res);
778 	if (err)
779 		return err;
780 
781 	pcie->base = devm_ioremap_resource(dev, &res);
782 	if (IS_ERR(pcie->base))
783 		return PTR_ERR(pcie->base);
784 
785 	host->bus_clk = devm_clk_get(dev, "pcie_bus");
786 	if (IS_ERR(host->bus_clk)) {
787 		dev_err(dev, "cannot get pcie bus clock\n");
788 		return PTR_ERR(host->bus_clk);
789 	}
790 
791 	i = irq_of_parse_and_map(dev->of_node, 0);
792 	if (!i) {
793 		dev_err(dev, "cannot get platform resources for msi interrupt\n");
794 		err = -ENOENT;
795 		goto err_irq1;
796 	}
797 	host->msi.irq1 = i;
798 
799 	i = irq_of_parse_and_map(dev->of_node, 1);
800 	if (!i) {
801 		dev_err(dev, "cannot get platform resources for msi interrupt\n");
802 		err = -ENOENT;
803 		goto err_irq2;
804 	}
805 	host->msi.irq2 = i;
806 
807 	return 0;
808 
809 err_irq2:
810 	irq_dispose_mapping(host->msi.irq1);
811 err_irq1:
812 	return err;
813 }
814 
815 static int rcar_pcie_inbound_ranges(struct rcar_pcie *pcie,
816 				    struct resource_entry *entry,
817 				    int *index)
818 {
819 	u64 restype = entry->res->flags;
820 	u64 cpu_addr = entry->res->start;
821 	u64 cpu_end = entry->res->end;
822 	u64 pci_addr = entry->res->start - entry->offset;
823 	u32 flags = LAM_64BIT | LAR_ENABLE;
824 	u64 mask;
825 	u64 size = resource_size(entry->res);
826 	int idx = *index;
827 
828 	if (restype & IORESOURCE_PREFETCH)
829 		flags |= LAM_PREFETCH;
830 
831 	while (cpu_addr < cpu_end) {
832 		if (idx >= MAX_NR_INBOUND_MAPS - 1) {
833 			dev_err(pcie->dev, "Failed to map inbound regions!\n");
834 			return -EINVAL;
835 		}
836 		/*
837 		 * If the size of the range is larger than the alignment of
838 		 * the start address, we have to use multiple entries to
839 		 * perform the mapping.
840 		 */
841 		if (cpu_addr > 0) {
842 			unsigned long nr_zeros = __ffs64(cpu_addr);
843 			u64 alignment = 1ULL << nr_zeros;
844 
845 			size = min(size, alignment);
846 		}
847 		/* Hardware supports max 4GiB inbound region */
848 		size = min(size, 1ULL << 32);
849 
850 		mask = roundup_pow_of_two(size) - 1;
851 		mask &= ~0xf;
852 
853 		rcar_pcie_set_inbound(pcie, cpu_addr, pci_addr,
854 				      lower_32_bits(mask) | flags, idx, true);
855 
856 		pci_addr += size;
857 		cpu_addr += size;
858 		idx += 2;
859 	}
860 	*index = idx;
861 
862 	return 0;
863 }
864 
865 static int rcar_pcie_parse_map_dma_ranges(struct rcar_pcie_host *host)
866 {
867 	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(host);
868 	struct resource_entry *entry;
869 	int index = 0, err = 0;
870 
871 	resource_list_for_each_entry(entry, &bridge->dma_ranges) {
872 		err = rcar_pcie_inbound_ranges(&host->pcie, entry, &index);
873 		if (err)
874 			break;
875 	}
876 
877 	return err;
878 }
879 
880 static const struct of_device_id rcar_pcie_of_match[] = {
881 	{ .compatible = "renesas,pcie-r8a7779",
882 	  .data = rcar_pcie_phy_init_h1 },
883 	{ .compatible = "renesas,pcie-r8a7790",
884 	  .data = rcar_pcie_phy_init_gen2 },
885 	{ .compatible = "renesas,pcie-r8a7791",
886 	  .data = rcar_pcie_phy_init_gen2 },
887 	{ .compatible = "renesas,pcie-rcar-gen2",
888 	  .data = rcar_pcie_phy_init_gen2 },
889 	{ .compatible = "renesas,pcie-r8a7795",
890 	  .data = rcar_pcie_phy_init_gen3 },
891 	{ .compatible = "renesas,pcie-rcar-gen3",
892 	  .data = rcar_pcie_phy_init_gen3 },
893 	{},
894 };
895 
896 static int rcar_pcie_probe(struct platform_device *pdev)
897 {
898 	struct device *dev = &pdev->dev;
899 	struct rcar_pcie_host *host;
900 	struct rcar_pcie *pcie;
901 	u32 data;
902 	int err;
903 	struct pci_host_bridge *bridge;
904 
905 	bridge = devm_pci_alloc_host_bridge(dev, sizeof(*host));
906 	if (!bridge)
907 		return -ENOMEM;
908 
909 	host = pci_host_bridge_priv(bridge);
910 	pcie = &host->pcie;
911 	pcie->dev = dev;
912 	platform_set_drvdata(pdev, host);
913 
914 	pm_runtime_enable(pcie->dev);
915 	err = pm_runtime_get_sync(pcie->dev);
916 	if (err < 0) {
917 		dev_err(pcie->dev, "pm_runtime_get_sync failed\n");
918 		goto err_pm_put;
919 	}
920 
921 	err = rcar_pcie_get_resources(host);
922 	if (err < 0) {
923 		dev_err(dev, "failed to request resources: %d\n", err);
924 		goto err_pm_put;
925 	}
926 
927 	err = clk_prepare_enable(host->bus_clk);
928 	if (err) {
929 		dev_err(dev, "failed to enable bus clock: %d\n", err);
930 		goto err_unmap_msi_irqs;
931 	}
932 
933 	err = rcar_pcie_parse_map_dma_ranges(host);
934 	if (err)
935 		goto err_clk_disable;
936 
937 	host->phy_init_fn = of_device_get_match_data(dev);
938 	err = host->phy_init_fn(host);
939 	if (err) {
940 		dev_err(dev, "failed to init PCIe PHY\n");
941 		goto err_clk_disable;
942 	}
943 
944 	/* Failure to get a link might just be that no cards are inserted */
945 	if (rcar_pcie_hw_init(pcie)) {
946 		dev_info(dev, "PCIe link down\n");
947 		err = -ENODEV;
948 		goto err_phy_shutdown;
949 	}
950 
951 	data = rcar_pci_read_reg(pcie, MACSR);
952 	dev_info(dev, "PCIe x%d: link up\n", (data >> 20) & 0x3f);
953 
954 	if (IS_ENABLED(CONFIG_PCI_MSI)) {
955 		err = rcar_pcie_enable_msi(host);
956 		if (err < 0) {
957 			dev_err(dev,
958 				"failed to enable MSI support: %d\n",
959 				err);
960 			goto err_phy_shutdown;
961 		}
962 	}
963 
964 	err = rcar_pcie_enable(host);
965 	if (err)
966 		goto err_msi_teardown;
967 
968 	return 0;
969 
970 err_msi_teardown:
971 	if (IS_ENABLED(CONFIG_PCI_MSI))
972 		rcar_pcie_teardown_msi(host);
973 
974 err_phy_shutdown:
975 	if (host->phy) {
976 		phy_power_off(host->phy);
977 		phy_exit(host->phy);
978 	}
979 
980 err_clk_disable:
981 	clk_disable_unprepare(host->bus_clk);
982 
983 err_unmap_msi_irqs:
984 	irq_dispose_mapping(host->msi.irq2);
985 	irq_dispose_mapping(host->msi.irq1);
986 
987 err_pm_put:
988 	pm_runtime_put(dev);
989 	pm_runtime_disable(dev);
990 
991 	return err;
992 }
993 
994 static int __maybe_unused rcar_pcie_resume(struct device *dev)
995 {
996 	struct rcar_pcie_host *host = dev_get_drvdata(dev);
997 	struct rcar_pcie *pcie = &host->pcie;
998 	unsigned int data;
999 	int err;
1000 
1001 	err = rcar_pcie_parse_map_dma_ranges(host);
1002 	if (err)
1003 		return 0;
1004 
1005 	/* Failure to get a link might just be that no cards are inserted */
1006 	err = host->phy_init_fn(host);
1007 	if (err) {
1008 		dev_info(dev, "PCIe link down\n");
1009 		return 0;
1010 	}
1011 
1012 	data = rcar_pci_read_reg(pcie, MACSR);
1013 	dev_info(dev, "PCIe x%d: link up\n", (data >> 20) & 0x3f);
1014 
1015 	/* Enable MSI */
1016 	if (IS_ENABLED(CONFIG_PCI_MSI))
1017 		rcar_pcie_hw_enable_msi(host);
1018 
1019 	rcar_pcie_hw_enable(host);
1020 
1021 	return 0;
1022 }
1023 
1024 static int rcar_pcie_resume_noirq(struct device *dev)
1025 {
1026 	struct rcar_pcie_host *host = dev_get_drvdata(dev);
1027 	struct rcar_pcie *pcie = &host->pcie;
1028 
1029 	if (rcar_pci_read_reg(pcie, PMSR) &&
1030 	    !(rcar_pci_read_reg(pcie, PCIETCTLR) & DL_DOWN))
1031 		return 0;
1032 
1033 	/* Re-establish the PCIe link */
1034 	rcar_pci_write_reg(pcie, MACCTLR_INIT_VAL, MACCTLR);
1035 	rcar_pci_write_reg(pcie, CFINIT, PCIETCTLR);
1036 	return rcar_pcie_wait_for_dl(pcie);
1037 }
1038 
1039 static const struct dev_pm_ops rcar_pcie_pm_ops = {
1040 	SET_SYSTEM_SLEEP_PM_OPS(NULL, rcar_pcie_resume)
1041 	.resume_noirq = rcar_pcie_resume_noirq,
1042 };
1043 
1044 static struct platform_driver rcar_pcie_driver = {
1045 	.driver = {
1046 		.name = "rcar-pcie",
1047 		.of_match_table = rcar_pcie_of_match,
1048 		.pm = &rcar_pcie_pm_ops,
1049 		.suppress_bind_attrs = true,
1050 	},
1051 	.probe = rcar_pcie_probe,
1052 };
1053 builtin_platform_driver(rcar_pcie_driver);
1054