xref: /freebsd/sys/arm/broadcom/bcm2835/bcm2838_pci.c (revision f126890ac5386406dadf7c4cfa9566cbb56537c5)
1 /*-
2  * SPDX-License-Identifier: ISC
3  *
4  * Copyright (c) 2020 Dr Robert Harvey Crowston <crowston@protonmail.com>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  *
18  *
19  */
20 
21 /*
22  * BCM2838-compatible PCI-express controller.
23  *
24  * Broadcom likes to give the same chip lots of different names. The name of
25  * this driver is taken from the Raspberry Pi 4 Broadcom 2838 chip.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/endian.h>
31 #include <sys/kernel.h>
32 #include <sys/module.h>
33 #include <sys/bus.h>
34 #include <sys/proc.h>
35 #include <sys/rman.h>
36 #include <sys/intr.h>
37 #include <sys/mutex.h>
38 
39 #include <dev/ofw/openfirm.h>
40 #include <dev/ofw/ofw_bus.h>
41 #include <dev/ofw/ofw_bus_subr.h>
42 
43 #include <dev/pci/pci_host_generic.h>
44 #include <dev/pci/pci_host_generic_fdt.h>
45 #include <dev/pci/pcivar.h>
46 #include <dev/pci/pcireg.h>
47 #include <dev/pci/pcib_private.h>
48 
49 #include <machine/bus.h>
50 #include <machine/intr.h>
51 
52 #include "pcib_if.h"
53 #include "msi_if.h"
54 
55 #define PCI_ID_VAL3		0x43c
56 #define CLASS_SHIFT		0x10
57 #define SUBCLASS_SHIFT		0x8
58 
59 #define REG_CONTROLLER_HW_REV			0x406c
60 #define REG_BRIDGE_CTRL				0x9210
61 #define BRIDGE_DISABLE_FLAG	0x1
62 #define BRIDGE_RESET_FLAG	0x2
63 #define REG_BRIDGE_SERDES_MODE			0x4204
64 #define REG_DMA_CONFIG				0x4008
65 #define REG_DMA_WINDOW_LOW			0x4034
66 #define REG_DMA_WINDOW_HIGH			0x4038
67 #define REG_DMA_WINDOW_1			0x403c
68 #define REG_BRIDGE_GISB_WINDOW			0x402c
69 #define REG_BRIDGE_STATE			0x4068
70 #define REG_BRIDGE_LINK_STATE			0x00bc
71 #define REG_BUS_WINDOW_LOW			0x400c
72 #define REG_BUS_WINDOW_HIGH			0x4010
73 #define REG_CPU_WINDOW_LOW			0x4070
74 #define REG_CPU_WINDOW_START_HIGH		0x4080
75 #define REG_CPU_WINDOW_END_HIGH			0x4084
76 
77 #define REG_MSI_ADDR_LOW			0x4044
78 #define REG_MSI_ADDR_HIGH			0x4048
79 #define REG_MSI_CONFIG				0x404c
80 #define REG_MSI_CLR				0x4508
81 #define REG_MSI_MASK_CLR			0x4514
82 #define REG_MSI_RAISED				0x4500
83 #define REG_MSI_EOI				0x4060
84 #define NUM_MSI			32
85 
86 #define REG_EP_CONFIG_CHOICE			0x9000
87 #define REG_EP_CONFIG_DATA			0x8000
88 
89 /*
90  * The system memory controller can address up to 16 GiB of physical memory
91  * (although at time of writing the largest memory size available for purchase
92  * is 8 GiB). However, the system DMA controller is capable of accessing only a
93  * limited portion of the address space. Worse, the PCI-e controller has further
94  * constraints for DMA, and those limitations are not wholly clear to the
95  * author. NetBSD and Linux allow DMA on the lower 3 GiB of the physical memory,
96  * but experimentation shows DMA performed above 960 MiB results in data
97  * corruption with this driver. The limit of 960 MiB is taken from OpenBSD, but
98  * apparently that value was chosen for satisfying a constraint of an unrelated
99  * peripheral.
100  *
101  * Whatever the true maximum address, 960 MiB works.
102  */
103 #define DMA_HIGH_LIMIT			0x3c000000
104 #define MAX_MEMORY_LOG2			0x21
105 #define REG_VALUE_DMA_WINDOW_LOW	(MAX_MEMORY_LOG2 - 0xf)
106 #define REG_VALUE_DMA_WINDOW_HIGH	0x0
107 #define DMA_WINDOW_ENABLE		0x3000
108 #define REG_VALUE_DMA_WINDOW_CONFIG	\
109     (((MAX_MEMORY_LOG2 - 0xf) << 0x1b) | DMA_WINDOW_ENABLE)
110 
111 #define REG_VALUE_MSI_CONFIG	0xffe06540
112 
113 struct bcm_pcib_irqsrc {
114 	struct intr_irqsrc	isrc;
115 	u_int			irq;
116 	bool			allocated;
117 };
118 
119 struct bcm_pcib_softc {
120 	struct generic_pcie_fdt_softc	base;
121 	device_t			dev;
122 	bus_dma_tag_t			dmat;
123 	struct mtx			config_mtx;
124 	struct mtx			msi_mtx;
125 	struct resource 		*msi_irq_res;
126 	void				*msi_intr_cookie;
127 	struct bcm_pcib_irqsrc		*msi_isrcs;
128 	pci_addr_t			msi_addr;
129 };
130 
131 static struct ofw_compat_data compat_data[] = {
132 	{"brcm,bcm2711-pcie",			1},
133 	{"brcm,bcm7211-pcie",			1},
134 	{"brcm,bcm7445-pcie",			1},
135 	{NULL,					0}
136 };
137 
138 static int
139 bcm_pcib_probe(device_t dev)
140 {
141 
142 	if (!ofw_bus_status_okay(dev))
143 		return (ENXIO);
144 
145 	if (!ofw_bus_search_compatible(dev, compat_data)->ocd_data)
146 		return (ENXIO);
147 
148 	device_set_desc(dev,
149 	    "BCM2838-compatible PCI-express controller");
150 	return (BUS_PROBE_DEFAULT);
151 }
152 
153 static bus_dma_tag_t
154 bcm_pcib_get_dma_tag(device_t dev, device_t child)
155 {
156 	struct bcm_pcib_softc *sc;
157 
158 	sc = device_get_softc(dev);
159 	return (sc->dmat);
160 }
161 
162 static void
163 bcm_pcib_set_reg(struct bcm_pcib_softc *sc, uint32_t reg, uint32_t val)
164 {
165 
166 	bus_write_4(sc->base.base.res, reg, htole32(val));
167 }
168 
169 static uint32_t
170 bcm_pcib_read_reg(struct bcm_pcib_softc *sc, uint32_t reg)
171 {
172 
173 	return (le32toh(bus_read_4(sc->base.base.res, reg)));
174 }
175 
176 static void
177 bcm_pcib_reset_controller(struct bcm_pcib_softc *sc)
178 {
179 	uint32_t val;
180 
181 	val = bcm_pcib_read_reg(sc, REG_BRIDGE_CTRL);
182 	val = val | BRIDGE_RESET_FLAG | BRIDGE_DISABLE_FLAG;
183 	bcm_pcib_set_reg(sc, REG_BRIDGE_CTRL, val);
184 
185 	DELAY(100);
186 
187 	val = bcm_pcib_read_reg(sc, REG_BRIDGE_CTRL);
188 	val = val & ~BRIDGE_RESET_FLAG;
189 	bcm_pcib_set_reg(sc, REG_BRIDGE_CTRL, val);
190 
191 	DELAY(100);
192 
193 	bcm_pcib_set_reg(sc, REG_BRIDGE_SERDES_MODE, 0);
194 
195 	DELAY(100);
196 }
197 
198 static void
199 bcm_pcib_enable_controller(struct bcm_pcib_softc *sc)
200 {
201 	uint32_t val;
202 
203 	val = bcm_pcib_read_reg(sc, REG_BRIDGE_CTRL);
204 	val = val & ~BRIDGE_DISABLE_FLAG;
205 	bcm_pcib_set_reg(sc, REG_BRIDGE_CTRL, val);
206 
207 	DELAY(100);
208 }
209 
210 static int
211 bcm_pcib_check_ranges(device_t dev)
212 {
213 	struct bcm_pcib_softc *sc;
214 	struct pcie_range *ranges;
215 	int error = 0, i;
216 
217 	sc = device_get_softc(dev);
218 	ranges = &sc->base.base.ranges[0];
219 
220 	/* The first range needs to be non-zero. */
221 	if (ranges[0].size == 0) {
222 		device_printf(dev, "error: first outbound memory range "
223 		    "(pci addr: 0x%jx, cpu addr: 0x%jx) has zero size.\n",
224 		    ranges[0].pci_base, ranges[0].phys_base);
225 		error = ENXIO;
226 	}
227 
228 	/*
229 	 * The controller can actually handle three distinct ranges, but we
230 	 * only implement support for one.
231 	 */
232 	for (i = 1; (bootverbose || error) && i < MAX_RANGES_TUPLES; ++i) {
233 		if (ranges[i].size > 0)
234 			device_printf(dev,
235 			    "note: outbound memory range %d (pci addr: 0x%jx, "
236 			    "cpu addr: 0x%jx, size: 0x%jx) will be ignored.\n",
237 			    i, ranges[i].pci_base, ranges[i].phys_base,
238 			    ranges[i].size);
239 	}
240 
241 	return (error);
242 }
243 
244 static const char *
245 bcm_pcib_link_state_string(uint32_t mode)
246 {
247 
248 	switch(mode & PCIEM_LINK_STA_SPEED) {
249 	case 0:
250 		return ("not up");
251 	case 1:
252 		return ("2.5 GT/s");
253 	case 2:
254 		return ("5.0 GT/s");
255 	case 4:
256 		return ("8.0 GT/s");
257 	default:
258 		return ("unknown");
259 	}
260 }
261 
262 static bus_addr_t
263 bcm_get_offset_and_prepare_config(struct bcm_pcib_softc *sc, u_int bus,
264     u_int slot, u_int func, u_int reg)
265 {
266 	/*
267 	 * Config for an end point is only available through a narrow window for
268 	 * one end point at a time. We first tell the controller which end point
269 	 * we want, then access it through the window.
270 	 */
271 	uint32_t func_index;
272 
273 	if (bus == 0 && slot == 0 && func == 0)
274 		/*
275 		 * Special case for root device; its config is always available
276 		 * through the zero-offset.
277 		 */
278 		return (reg);
279 
280 	/* Tell the controller to show us the config in question. */
281 	func_index = PCIE_ADDR_OFFSET(bus, slot, func, 0);
282 	bcm_pcib_set_reg(sc, REG_EP_CONFIG_CHOICE, func_index);
283 
284 	return (REG_EP_CONFIG_DATA + reg);
285 }
286 
287 static bool
288 bcm_pcib_is_valid_quad(struct bcm_pcib_softc *sc, u_int bus, u_int slot,
289     u_int func, u_int reg)
290 {
291 
292 	if ((bus < sc->base.base.bus_start) || (bus > sc->base.base.bus_end))
293 		return (false);
294 	if ((slot > PCI_SLOTMAX) || (func > PCI_FUNCMAX) || (reg > PCIE_REGMAX))
295 		return (false);
296 
297 	if (bus == 0 && slot == 0 && func == 0)
298 		return (true);
299 	if (bus == 0)
300 		/*
301 		 * Probing other slots and funcs on bus 0 will lock up the
302 		 * memory controller.
303 		 */
304 		return (false);
305 
306 	return (true);
307 }
308 
309 static uint32_t
310 bcm_pcib_read_config(device_t dev, u_int bus, u_int slot, u_int func, u_int reg,
311     int bytes)
312 {
313 	struct bcm_pcib_softc *sc;
314 	bus_addr_t offset;
315 	uint32_t data;
316 
317 	sc = device_get_softc(dev);
318 	if (!bcm_pcib_is_valid_quad(sc, bus, slot, func, reg))
319 		return (~0U);
320 
321 	mtx_lock(&sc->config_mtx);
322 	offset = bcm_get_offset_and_prepare_config(sc, bus, slot, func, reg);
323 
324 	switch (bytes) {
325 	case 1:
326 		data = bus_read_1(sc->base.base.res, offset);
327 		break;
328 	case 2:
329 		data = le16toh(bus_read_2(sc->base.base.res, offset));
330 		break;
331 	case 4:
332 		data = le32toh(bus_read_4(sc->base.base.res, offset));
333 		break;
334 	default:
335 		data = ~0U;
336 		break;
337 	}
338 
339 	mtx_unlock(&sc->config_mtx);
340 	return (data);
341 }
342 
343 static void
344 bcm_pcib_write_config(device_t dev, u_int bus, u_int slot,
345     u_int func, u_int reg, uint32_t val, int bytes)
346 {
347 	struct bcm_pcib_softc *sc;
348 	uint32_t offset;
349 
350 	sc = device_get_softc(dev);
351 	if (!bcm_pcib_is_valid_quad(sc, bus, slot, func, reg))
352 		return;
353 
354 	mtx_lock(&sc->config_mtx);
355 	offset = bcm_get_offset_and_prepare_config(sc, bus, slot, func, reg);
356 
357 	switch (bytes) {
358 	case 1:
359 		bus_write_1(sc->base.base.res, offset, val);
360 		break;
361 	case 2:
362 		bus_write_2(sc->base.base.res, offset, htole16(val));
363 		break;
364 	case 4:
365 		bus_write_4(sc->base.base.res, offset, htole32(val));
366 		break;
367 	default:
368 		break;
369 	}
370 
371 	mtx_unlock(&sc->config_mtx);
372 }
373 
374 static void
375 bcm_pcib_msi_intr_process(struct bcm_pcib_softc *sc, uint32_t interrupt_bitmap,
376     struct trapframe *tf)
377 {
378 	struct bcm_pcib_irqsrc *irqsrc;
379 	uint32_t bit, irq;
380 
381 	while ((bit = ffs(interrupt_bitmap))) {
382 		irq = bit - 1;
383 
384 		/* Acknowledge interrupt. */
385 		bcm_pcib_set_reg(sc, REG_MSI_CLR, 1 << irq);
386 
387 		/* Send EOI. */
388 		bcm_pcib_set_reg(sc, REG_MSI_EOI, 1);
389 
390 		/* Despatch to handler. */
391 		irqsrc = &sc->msi_isrcs[irq];
392 		if (intr_isrc_dispatch(&irqsrc->isrc, tf))
393 			device_printf(sc->dev,
394 			    "note: unexpected interrupt (%d) triggered.\n",
395 			    irq);
396 
397 		/* Done with this interrupt. */
398 		interrupt_bitmap = interrupt_bitmap & ~(1 << irq);
399 	}
400 }
401 
402 static int
403 bcm_pcib_msi_intr(void *arg)
404 {
405 	struct bcm_pcib_softc *sc;
406 	struct trapframe *tf;
407 	uint32_t interrupt_bitmap;
408 
409 	sc = (struct bcm_pcib_softc *) arg;
410 	tf = curthread->td_intr_frame;
411 
412 	while ((interrupt_bitmap = bcm_pcib_read_reg(sc, REG_MSI_RAISED)))
413 		bcm_pcib_msi_intr_process(sc, interrupt_bitmap, tf);
414 
415 	return (FILTER_HANDLED);
416 }
417 
418 static int
419 bcm_pcib_alloc_msi(device_t dev, device_t child, int count, int maxcount,
420     device_t *pic, struct intr_irqsrc **srcs)
421 {
422 	struct bcm_pcib_softc *sc;
423 	int first_int, i;
424 
425 	sc = device_get_softc(dev);
426 	mtx_lock(&sc->msi_mtx);
427 
428 	/* Find a continguous region of free message-signalled interrupts. */
429 	for (first_int = 0; first_int + count < NUM_MSI; ) {
430 		for (i = first_int; i < first_int + count; ++i) {
431 			if (sc->msi_isrcs[i].allocated)
432 				goto next;
433 		}
434 		goto found;
435 next:
436 		first_int = i + 1;
437 	}
438 
439 	/* No appropriate region available. */
440 	mtx_unlock(&sc->msi_mtx);
441 	device_printf(dev, "warning: failed to allocate %d MSI messages.\n",
442 	    count);
443 	return (ENXIO);
444 
445 found:
446 	/* Mark the messages as in use. */
447 	for (i = 0; i < count; ++i) {
448 		sc->msi_isrcs[i + first_int].allocated = true;
449 		srcs[i] = &(sc->msi_isrcs[i + first_int].isrc);
450 	}
451 
452 	mtx_unlock(&sc->msi_mtx);
453 	*pic = device_get_parent(dev);
454 
455 	return (0);
456 }
457 
458 static int
459 bcm_pcib_map_msi(device_t dev, device_t child, struct intr_irqsrc *isrc,
460     uint64_t *addr, uint32_t *data)
461 {
462 	struct bcm_pcib_softc *sc;
463 	struct bcm_pcib_irqsrc *msi_msg;
464 
465 	sc = device_get_softc(dev);
466 	msi_msg = (struct bcm_pcib_irqsrc *) isrc;
467 
468 	*addr = sc->msi_addr;
469 	*data = (REG_VALUE_MSI_CONFIG & 0xffff) | msi_msg->irq;
470 	return (0);
471 }
472 
473 static int
474 bcm_pcib_release_msi(device_t dev, device_t child, int count,
475     struct intr_irqsrc **isrc)
476 {
477 	struct bcm_pcib_softc *sc;
478 	struct bcm_pcib_irqsrc *msi_isrc;
479 	int i;
480 
481 	sc = device_get_softc(dev);
482 	mtx_lock(&sc->msi_mtx);
483 
484 	for (i = 0; i < count; i++) {
485 		msi_isrc = (struct bcm_pcib_irqsrc *) isrc[i];
486 		msi_isrc->allocated = false;
487 	}
488 
489 	mtx_unlock(&sc->msi_mtx);
490 	return (0);
491 }
492 
493 static int
494 bcm_pcib_msi_attach(device_t dev)
495 {
496 	struct bcm_pcib_softc *sc;
497 	phandle_t node, xref;
498 	char const *bcm_name;
499 	int error, i, rid;
500 
501 	sc = device_get_softc(dev);
502 	sc->msi_addr = 0xffffffffc;
503 
504 	/* Clear any pending interrupts. */
505 	bcm_pcib_set_reg(sc, REG_MSI_CLR, 0xffffffff);
506 
507 	rid = 1;
508 	sc->msi_irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
509 	    RF_ACTIVE);
510 	if (sc->msi_irq_res == NULL) {
511 		device_printf(dev, "could not allocate MSI irq resource.\n");
512 		return (ENXIO);
513 	}
514 
515 	sc->msi_isrcs = malloc(sizeof(*sc->msi_isrcs) * NUM_MSI, M_DEVBUF,
516 	    M_WAITOK | M_ZERO);
517 
518 	error = bus_setup_intr(dev, sc->msi_irq_res, INTR_TYPE_BIO |
519 	    INTR_MPSAFE, bcm_pcib_msi_intr, NULL, sc, &sc->msi_intr_cookie);
520 	if (error != 0) {
521 		device_printf(dev, "error: failed to setup MSI handler.\n");
522 		return (error);
523 	}
524 
525 	bcm_name = device_get_nameunit(dev);
526 	for (i = 0; i < NUM_MSI; i++) {
527 		sc->msi_isrcs[i].irq = i;
528 		error = intr_isrc_register(&sc->msi_isrcs[i].isrc, dev, 0,
529 		    "%s,%u", bcm_name, i);
530 		if (error != 0) {
531 			device_printf(dev,
532 			    "error: failed to register interrupt %d.\n", i);
533 			return (error);
534 		}
535 	}
536 
537 	node = ofw_bus_get_node(dev);
538 	xref = OF_xref_from_node(node);
539 	OF_device_register_xref(xref, dev);
540 
541 	error = intr_msi_register(dev, xref);
542 	if (error != 0)
543 		return (error);
544 
545 	mtx_init(&sc->msi_mtx, "bcm_pcib: msi_mtx", NULL, MTX_DEF);
546 
547 	bcm_pcib_set_reg(sc, REG_MSI_MASK_CLR, 0xffffffff);
548 	bcm_pcib_set_reg(sc, REG_MSI_ADDR_LOW, (sc->msi_addr & 0xffffffff) | 1);
549 	bcm_pcib_set_reg(sc, REG_MSI_ADDR_HIGH, (sc->msi_addr >> 32));
550 	bcm_pcib_set_reg(sc, REG_MSI_CONFIG, REG_VALUE_MSI_CONFIG);
551 
552 	return (0);
553 }
554 
555 static void
556 bcm_pcib_relocate_bridge_window(device_t dev)
557 {
558 	/*
559 	 * In principle an out-of-bounds bridge window could be automatically
560 	 * adjusted at resource-activation time to lie within the bus address
561 	 * space by pcib_grow_window(), but that is not possible because the
562 	 * out-of-bounds resource allocation fails at allocation time. Instead,
563 	 * we will just fix up the window on the controller here, before it is
564 	 * re-discovered by pcib_probe_windows().
565 	 */
566 
567 	struct bcm_pcib_softc *sc;
568 	pci_addr_t base, size, new_base, new_limit;
569 	uint16_t val;
570 
571 	sc = device_get_softc(dev);
572 
573 	val = bcm_pcib_read_config(dev, 0, 0, 0, PCIR_MEMBASE_1, 2);
574 	base = PCI_PPBMEMBASE(0, val);
575 
576 	val = bcm_pcib_read_config(dev, 0, 0, 0, PCIR_MEMLIMIT_1, 2);
577 	size = PCI_PPBMEMLIMIT(0, val) - base;
578 
579 	new_base = sc->base.base.ranges[0].pci_base;
580 	val = (uint16_t) (new_base >> 16);
581 	bcm_pcib_write_config(dev, 0, 0, 0, PCIR_MEMBASE_1, val, 2);
582 
583 	new_limit = new_base + size;
584 	val = (uint16_t) (new_limit >> 16);
585 	bcm_pcib_write_config(dev, 0, 0, 0, PCIR_MEMLIMIT_1, val, 2);
586 }
587 
588 static uint32_t
589 encode_cpu_window_low(pci_addr_t phys_base, bus_size_t size)
590 {
591 
592 	return (((phys_base >> 0x10) & 0xfff0) |
593 	    ((phys_base + size - 1) & 0xfff00000));
594 }
595 
596 static uint32_t
597 encode_cpu_window_start_high(pci_addr_t phys_base)
598 {
599 
600 	return ((phys_base >> 0x20) & 0xff);
601 }
602 
603 static uint32_t
604 encode_cpu_window_end_high(pci_addr_t phys_base, bus_size_t size)
605 {
606 
607 	return (((phys_base + size - 1) >> 0x20) & 0xff);
608 }
609 
610 static int
611 bcm_pcib_attach(device_t dev)
612 {
613 	struct bcm_pcib_softc *sc;
614 	pci_addr_t phys_base, pci_base;
615 	bus_size_t size;
616 	uint32_t hardware_rev, bridge_state, link_state;
617 	int error, tries;
618 
619 	sc = device_get_softc(dev);
620 	sc->dev = dev;
621 
622 	/*
623 	 * This tag will be used in preference to the one created in
624 	 * pci_host_generic.c.
625 	 */
626 	error = bus_dma_tag_create(bus_get_dma_tag(dev), /* parent */
627 	    1, 0,				/* alignment, bounds */
628 	    DMA_HIGH_LIMIT,			/* lowaddr */
629 	    BUS_SPACE_MAXADDR,			/* highaddr */
630 	    NULL, NULL,				/* filter, filterarg */
631 	    DMA_HIGH_LIMIT,			/* maxsize */
632 	    BUS_SPACE_UNRESTRICTED,		/* nsegments */
633 	    DMA_HIGH_LIMIT,			/* maxsegsize */
634 	    0, 					/* flags */
635 	    NULL, NULL,				/* lockfunc, lockarg */
636 	    &sc->dmat);
637 	if (error != 0)
638 		return (error);
639 
640 	error = pci_host_generic_setup_fdt(dev);
641 	if (error != 0)
642 		return (error);
643 
644 	error = bcm_pcib_check_ranges(dev);
645 	if (error != 0)
646 		return (error);
647 
648 	mtx_init(&sc->config_mtx, "bcm_pcib: config_mtx", NULL, MTX_DEF);
649 
650 	bcm_pcib_reset_controller(sc);
651 
652 	hardware_rev = bcm_pcib_read_reg(sc, REG_CONTROLLER_HW_REV) & 0xffff;
653 	device_printf(dev, "hardware identifies as revision 0x%x.\n",
654 	    hardware_rev);
655 
656 	/*
657 	 * Set PCI->CPU memory window. This encodes the inbound window showing
658 	 * the system memory to the controller.
659 	 */
660 	bcm_pcib_set_reg(sc, REG_DMA_WINDOW_LOW, REG_VALUE_DMA_WINDOW_LOW);
661 	bcm_pcib_set_reg(sc, REG_DMA_WINDOW_HIGH, REG_VALUE_DMA_WINDOW_HIGH);
662 	bcm_pcib_set_reg(sc, REG_DMA_CONFIG, REG_VALUE_DMA_WINDOW_CONFIG);
663 
664 	bcm_pcib_set_reg(sc, REG_BRIDGE_GISB_WINDOW, 0);
665 	bcm_pcib_set_reg(sc, REG_DMA_WINDOW_1, 0);
666 
667 	bcm_pcib_enable_controller(sc);
668 
669 	/* Wait for controller to start. */
670 	for(tries = 0; ; ++tries) {
671 		bridge_state = bcm_pcib_read_reg(sc, REG_BRIDGE_STATE);
672 
673 		if ((bridge_state & 0x30) == 0x30)
674 			/* Controller ready. */
675 			break;
676 
677 		if (tries > 100) {
678 			device_printf(dev,
679 			    "error: controller failed to start.\n");
680 			return (ENXIO);
681 		}
682 
683 		DELAY(1000);
684 	}
685 
686 	link_state = bcm_pcib_read_reg(sc, REG_BRIDGE_LINK_STATE) >> 0x10;
687 	if (!link_state) {
688 		device_printf(dev, "error: controller started but link is not "
689 		    "up.\n");
690 		return (ENXIO);
691 	}
692 	if (bootverbose)
693 		device_printf(dev, "note: reported link speed is %s.\n",
694 		    bcm_pcib_link_state_string(link_state));
695 
696 	/*
697 	 * Set the CPU->PCI memory window. The map in this direction is not 1:1.
698 	 * Addresses seen by the CPU need to be adjusted to make sense to the
699 	 * controller as they pass through the window.
700 	 */
701 	pci_base  = sc->base.base.ranges[0].pci_base;
702 	phys_base = sc->base.base.ranges[0].phys_base;
703 	size      = sc->base.base.ranges[0].size;
704 
705 	bcm_pcib_set_reg(sc, REG_BUS_WINDOW_LOW, pci_base & 0xffffffff);
706 	bcm_pcib_set_reg(sc, REG_BUS_WINDOW_HIGH, pci_base >> 32);
707 
708 	bcm_pcib_set_reg(sc, REG_CPU_WINDOW_LOW,
709 	    encode_cpu_window_low(phys_base, size));
710 	bcm_pcib_set_reg(sc, REG_CPU_WINDOW_START_HIGH,
711 	    encode_cpu_window_start_high(phys_base));
712 	bcm_pcib_set_reg(sc, REG_CPU_WINDOW_END_HIGH,
713 	    encode_cpu_window_end_high(phys_base, size));
714 
715 	/*
716 	 * The controller starts up declaring itself an endpoint; readvertise it
717 	 * as a bridge.
718 	 */
719 	bcm_pcib_set_reg(sc, PCI_ID_VAL3,
720 	    PCIC_BRIDGE << CLASS_SHIFT | PCIS_BRIDGE_PCI << SUBCLASS_SHIFT);
721 
722 	bcm_pcib_set_reg(sc, REG_BRIDGE_SERDES_MODE, 0x2);
723 	DELAY(100);
724 
725 	bcm_pcib_relocate_bridge_window(dev);
726 
727 	/* Configure interrupts. */
728 	error = bcm_pcib_msi_attach(dev);
729 	if (error != 0)
730 		return (error);
731 
732 	/* Done. */
733 	device_add_child(dev, "pci", -1);
734 	return (bus_generic_attach(dev));
735 }
736 
737 /*
738  * Device method table.
739  */
740 static device_method_t bcm_pcib_methods[] = {
741 	/* Bus interface. */
742 	DEVMETHOD(bus_get_dma_tag,		bcm_pcib_get_dma_tag),
743 
744 	/* Device interface. */
745 	DEVMETHOD(device_probe,			bcm_pcib_probe),
746 	DEVMETHOD(device_attach,		bcm_pcib_attach),
747 
748 	/* PCIB interface. */
749 	DEVMETHOD(pcib_read_config,		bcm_pcib_read_config),
750 	DEVMETHOD(pcib_write_config,		bcm_pcib_write_config),
751 
752 	/* MSI interface. */
753 	DEVMETHOD(msi_alloc_msi,		bcm_pcib_alloc_msi),
754 	DEVMETHOD(msi_release_msi,		bcm_pcib_release_msi),
755 	DEVMETHOD(msi_map_msi,			bcm_pcib_map_msi),
756 
757 	DEVMETHOD_END
758 };
759 
760 DEFINE_CLASS_1(pcib, bcm_pcib_driver, bcm_pcib_methods,
761     sizeof(struct bcm_pcib_softc), generic_pcie_fdt_driver);
762 
763 DRIVER_MODULE(bcm_pcib, simplebus, bcm_pcib_driver, 0, 0);
764 
765