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