1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * PCIe host bridge driver for Apple system-on-chips.
4  *
5  * The HW is ECAM compliant, so once the controller is initialized,
6  * the driver mostly deals MSI mapping and handling of per-port
7  * interrupts (INTx, management and error signals).
8  *
9  * Initialization requires enabling power and clocks, along with a
10  * number of register pokes.
11  *
12  * Copyright (C) 2021 Alyssa Rosenzweig <alyssa@rosenzweig.io>
13  * Copyright (C) 2021 Google LLC
14  * Copyright (C) 2021 Corellium LLC
15  * Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org>
16  *
17  * Author: Alyssa Rosenzweig <alyssa@rosenzweig.io>
18  * Author: Marc Zyngier <maz@kernel.org>
19  */
20 
21 #include <linux/bitfield.h>
22 #include <linux/gpio/consumer.h>
23 #include <linux/kernel.h>
24 #include <linux/iopoll.h>
25 #include <linux/irqchip/chained_irq.h>
26 #include <linux/irqchip/irq-msi-lib.h>
27 #include <linux/irqdomain.h>
28 #include <linux/list.h>
29 #include <linux/module.h>
30 #include <linux/msi.h>
31 #include <linux/of_irq.h>
32 #include <linux/pci-ecam.h>
33 
34 #include "pci-host-common.h"
35 
36 /* T8103 (original M1) and related SoCs */
37 #define CORE_RC_PHYIF_CTL		0x00024
38 #define   CORE_RC_PHYIF_CTL_RUN		BIT(0)
39 #define CORE_RC_PHYIF_STAT		0x00028
40 #define   CORE_RC_PHYIF_STAT_REFCLK	BIT(4)
41 #define CORE_RC_CTL			0x00050
42 #define   CORE_RC_CTL_RUN		BIT(0)
43 #define CORE_RC_STAT			0x00058
44 #define   CORE_RC_STAT_READY		BIT(0)
45 #define CORE_FABRIC_STAT		0x04000
46 #define   CORE_FABRIC_STAT_MASK		0x001F001F
47 
48 #define CORE_PHY_DEFAULT_BASE(port)	(0x84000 + 0x4000 * (port))
49 
50 #define PHY_LANE_CFG			0x00000
51 #define   PHY_LANE_CFG_REFCLK0REQ	BIT(0)
52 #define   PHY_LANE_CFG_REFCLK1REQ	BIT(1)
53 #define   PHY_LANE_CFG_REFCLK0ACK	BIT(2)
54 #define   PHY_LANE_CFG_REFCLK1ACK	BIT(3)
55 #define   PHY_LANE_CFG_REFCLKEN		(BIT(9) | BIT(10))
56 #define   PHY_LANE_CFG_REFCLKCGEN	(BIT(30) | BIT(31))
57 #define PHY_LANE_CTL			0x00004
58 #define   PHY_LANE_CTL_CFGACC		BIT(15)
59 
60 #define PORT_LTSSMCTL			0x00080
61 #define   PORT_LTSSMCTL_START		BIT(0)
62 #define PORT_INTSTAT			0x00100
63 #define   PORT_INT_TUNNEL_ERR		31
64 #define   PORT_INT_CPL_TIMEOUT		23
65 #define   PORT_INT_RID2SID_MAPERR	22
66 #define   PORT_INT_CPL_ABORT		21
67 #define   PORT_INT_MSI_BAD_DATA		19
68 #define   PORT_INT_MSI_ERR		18
69 #define   PORT_INT_REQADDR_GT32		17
70 #define   PORT_INT_AF_TIMEOUT		15
71 #define   PORT_INT_LINK_DOWN		14
72 #define   PORT_INT_LINK_UP		12
73 #define   PORT_INT_LINK_BWMGMT		11
74 #define   PORT_INT_AER_MASK		(15 << 4)
75 #define   PORT_INT_PORT_ERR		4
76 #define   PORT_INT_INTx(i)		i
77 #define   PORT_INT_INTx_MASK		15
78 #define PORT_INTMSK			0x00104
79 #define PORT_INTMSKSET			0x00108
80 #define PORT_INTMSKCLR			0x0010c
81 #define PORT_MSICFG			0x00124
82 #define   PORT_MSICFG_EN		BIT(0)
83 #define   PORT_MSICFG_L2MSINUM_SHIFT	4
84 #define PORT_MSIBASE			0x00128
85 #define   PORT_MSIBASE_1_SHIFT		16
86 #define PORT_MSIADDR			0x00168
87 #define PORT_LINKSTS			0x00208
88 #define   PORT_LINKSTS_UP		BIT(0)
89 #define   PORT_LINKSTS_BUSY		BIT(2)
90 #define PORT_LINKCMDSTS			0x00210
91 #define PORT_OUTS_NPREQS		0x00284
92 #define   PORT_OUTS_NPREQS_REQ		BIT(24)
93 #define   PORT_OUTS_NPREQS_CPL		BIT(16)
94 #define PORT_RXWR_FIFO			0x00288
95 #define   PORT_RXWR_FIFO_HDR		GENMASK(15, 10)
96 #define   PORT_RXWR_FIFO_DATA		GENMASK(9, 0)
97 #define PORT_RXRD_FIFO			0x0028C
98 #define   PORT_RXRD_FIFO_REQ		GENMASK(6, 0)
99 #define PORT_OUTS_CPLS			0x00290
100 #define   PORT_OUTS_CPLS_SHRD		GENMASK(14, 8)
101 #define   PORT_OUTS_CPLS_WAIT		GENMASK(6, 0)
102 #define PORT_APPCLK			0x00800
103 #define   PORT_APPCLK_EN		BIT(0)
104 #define   PORT_APPCLK_CGDIS		BIT(8)
105 #define PORT_STATUS			0x00804
106 #define   PORT_STATUS_READY		BIT(0)
107 #define PORT_REFCLK			0x00810
108 #define   PORT_REFCLK_EN		BIT(0)
109 #define   PORT_REFCLK_CGDIS		BIT(8)
110 #define PORT_PERST			0x00814
111 #define   PORT_PERST_OFF		BIT(0)
112 #define PORT_RID2SID			0x00828
113 #define   PORT_RID2SID_VALID		BIT(31)
114 #define   PORT_RID2SID_SID_SHIFT	16
115 #define   PORT_RID2SID_BUS_SHIFT	8
116 #define   PORT_RID2SID_DEV_SHIFT	3
117 #define   PORT_RID2SID_FUNC_SHIFT	0
118 #define PORT_OUTS_PREQS_HDR		0x00980
119 #define   PORT_OUTS_PREQS_HDR_MASK	GENMASK(9, 0)
120 #define PORT_OUTS_PREQS_DATA		0x00984
121 #define   PORT_OUTS_PREQS_DATA_MASK	GENMASK(15, 0)
122 #define PORT_TUNCTRL			0x00988
123 #define   PORT_TUNCTRL_PERST_ON		BIT(0)
124 #define   PORT_TUNCTRL_PERST_ACK_REQ	BIT(1)
125 #define PORT_TUNSTAT			0x0098c
126 #define   PORT_TUNSTAT_PERST_ON		BIT(0)
127 #define   PORT_TUNSTAT_PERST_ACK_PEND	BIT(1)
128 #define PORT_PREFMEM_ENABLE		0x00994
129 
130 /* T602x (M2-pro and co) */
131 #define PORT_T602X_MSIADDR	0x016c
132 #define PORT_T602X_MSIADDR_HI	0x0170
133 #define PORT_T602X_PERST	0x082c
134 #define PORT_T602X_RID2SID	0x3000
135 #define PORT_T602X_MSIMAP	0x3800
136 
137 #define PORT_MSIMAP_ENABLE	BIT(31)
138 #define PORT_MSIMAP_TARGET	GENMASK(7, 0)
139 
140 /*
141  * The doorbell address is set to 0xfffff000, which by convention
142  * matches what MacOS does, and it is possible to use any other
143  * address (in the bottom 4GB, as the base register is only 32bit).
144  * However, it has to be excluded from the IOVA range, and the DART
145  * driver has to know about it.
146  */
147 #define DOORBELL_ADDR		CONFIG_PCIE_APPLE_MSI_DOORBELL_ADDR
148 
149 struct hw_info {
150 	u32 phy_lane_ctl;
151 	u32 port_msiaddr;
152 	u32 port_msiaddr_hi;
153 	u32 port_refclk;
154 	u32 port_perst;
155 	u32 port_rid2sid;
156 	u32 port_msimap;
157 	u32 max_rid2sid;
158 };
159 
160 static const struct hw_info t8103_hw = {
161 	.phy_lane_ctl		= PHY_LANE_CTL,
162 	.port_msiaddr		= PORT_MSIADDR,
163 	.port_msiaddr_hi	= 0,
164 	.port_refclk		= PORT_REFCLK,
165 	.port_perst		= PORT_PERST,
166 	.port_rid2sid		= PORT_RID2SID,
167 	.port_msimap		= 0,
168 	.max_rid2sid		= 64,
169 };
170 
171 static const struct hw_info t602x_hw = {
172 	.phy_lane_ctl		= 0,
173 	.port_msiaddr		= PORT_T602X_MSIADDR,
174 	.port_msiaddr_hi	= PORT_T602X_MSIADDR_HI,
175 	.port_refclk		= 0,
176 	.port_perst		= PORT_T602X_PERST,
177 	.port_rid2sid		= PORT_T602X_RID2SID,
178 	.port_msimap		= PORT_T602X_MSIMAP,
179 	/* 16 on t602x, guess for autodetect on future HW */
180 	.max_rid2sid		= 512,
181 };
182 
183 struct apple_pcie {
184 	struct mutex		lock;
185 	struct device		*dev;
186 	void __iomem            *base;
187 	const struct hw_info	*hw;
188 	unsigned long		*bitmap;
189 	struct list_head	ports;
190 	struct completion	event;
191 	struct irq_fwspec	fwspec;
192 	u32			nvecs;
193 };
194 
195 struct apple_pcie_port {
196 	raw_spinlock_t		lock;
197 	struct apple_pcie	*pcie;
198 	struct device_node	*np;
199 	void __iomem		*base;
200 	void __iomem		*phy;
201 	struct irq_domain	*domain;
202 	struct list_head	entry;
203 	unsigned long		*sid_map;
204 	int			sid_map_sz;
205 	int			idx;
206 };
207 
208 static void rmw_set(u32 set, void __iomem *addr)
209 {
210 	writel_relaxed(readl_relaxed(addr) | set, addr);
211 }
212 
213 static void rmw_clear(u32 clr, void __iomem *addr)
214 {
215 	writel_relaxed(readl_relaxed(addr) & ~clr, addr);
216 }
217 
218 static void apple_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
219 {
220 	msg->address_hi = upper_32_bits(DOORBELL_ADDR);
221 	msg->address_lo = lower_32_bits(DOORBELL_ADDR);
222 	msg->data = data->hwirq;
223 }
224 
225 static struct irq_chip apple_msi_bottom_chip = {
226 	.name			= "MSI",
227 	.irq_mask		= irq_chip_mask_parent,
228 	.irq_unmask		= irq_chip_unmask_parent,
229 	.irq_eoi		= irq_chip_eoi_parent,
230 	.irq_set_affinity	= irq_chip_set_affinity_parent,
231 	.irq_set_type		= irq_chip_set_type_parent,
232 	.irq_compose_msi_msg	= apple_msi_compose_msg,
233 };
234 
235 static int apple_msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
236 				  unsigned int nr_irqs, void *args)
237 {
238 	struct apple_pcie *pcie = domain->host_data;
239 	struct irq_fwspec fwspec = pcie->fwspec;
240 	unsigned int i;
241 	int ret, hwirq;
242 
243 	mutex_lock(&pcie->lock);
244 
245 	hwirq = bitmap_find_free_region(pcie->bitmap, pcie->nvecs,
246 					order_base_2(nr_irqs));
247 
248 	mutex_unlock(&pcie->lock);
249 
250 	if (hwirq < 0)
251 		return -ENOSPC;
252 
253 	fwspec.param[fwspec.param_count - 2] += hwirq;
254 
255 	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &fwspec);
256 	if (ret)
257 		return ret;
258 
259 	for (i = 0; i < nr_irqs; i++) {
260 		irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
261 					      &apple_msi_bottom_chip, pcie);
262 	}
263 
264 	return 0;
265 }
266 
267 static void apple_msi_domain_free(struct irq_domain *domain, unsigned int virq,
268 				  unsigned int nr_irqs)
269 {
270 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
271 	struct apple_pcie *pcie = domain->host_data;
272 
273 	mutex_lock(&pcie->lock);
274 
275 	bitmap_release_region(pcie->bitmap, d->hwirq, order_base_2(nr_irqs));
276 
277 	mutex_unlock(&pcie->lock);
278 }
279 
280 static const struct irq_domain_ops apple_msi_domain_ops = {
281 	.alloc	= apple_msi_domain_alloc,
282 	.free	= apple_msi_domain_free,
283 };
284 
285 static void apple_port_irq_mask(struct irq_data *data)
286 {
287 	struct apple_pcie_port *port = irq_data_get_irq_chip_data(data);
288 
289 	guard(raw_spinlock_irqsave)(&port->lock);
290 	rmw_set(BIT(data->hwirq), port->base + PORT_INTMSK);
291 }
292 
293 static void apple_port_irq_unmask(struct irq_data *data)
294 {
295 	struct apple_pcie_port *port = irq_data_get_irq_chip_data(data);
296 
297 	guard(raw_spinlock_irqsave)(&port->lock);
298 	rmw_clear(BIT(data->hwirq), port->base + PORT_INTMSK);
299 }
300 
301 static bool hwirq_is_intx(unsigned int hwirq)
302 {
303 	return BIT(hwirq) & PORT_INT_INTx_MASK;
304 }
305 
306 static void apple_port_irq_ack(struct irq_data *data)
307 {
308 	struct apple_pcie_port *port = irq_data_get_irq_chip_data(data);
309 
310 	if (!hwirq_is_intx(data->hwirq))
311 		writel_relaxed(BIT(data->hwirq), port->base + PORT_INTSTAT);
312 }
313 
314 static int apple_port_irq_set_type(struct irq_data *data, unsigned int type)
315 {
316 	/*
317 	 * It doesn't seem that there is any way to configure the
318 	 * trigger, so assume INTx have to be level (as per the spec),
319 	 * and the rest is edge (which looks likely).
320 	 */
321 	if (hwirq_is_intx(data->hwirq) ^ !!(type & IRQ_TYPE_LEVEL_MASK))
322 		return -EINVAL;
323 
324 	irqd_set_trigger_type(data, type);
325 	return 0;
326 }
327 
328 static struct irq_chip apple_port_irqchip = {
329 	.name		= "PCIe",
330 	.irq_ack	= apple_port_irq_ack,
331 	.irq_mask	= apple_port_irq_mask,
332 	.irq_unmask	= apple_port_irq_unmask,
333 	.irq_set_type	= apple_port_irq_set_type,
334 };
335 
336 static int apple_port_irq_domain_alloc(struct irq_domain *domain,
337 				       unsigned int virq, unsigned int nr_irqs,
338 				       void *args)
339 {
340 	struct apple_pcie_port *port = domain->host_data;
341 	struct irq_fwspec *fwspec = args;
342 	int i;
343 
344 	for (i = 0; i < nr_irqs; i++) {
345 		irq_flow_handler_t flow = handle_edge_irq;
346 		unsigned int type = IRQ_TYPE_EDGE_RISING;
347 
348 		if (hwirq_is_intx(fwspec->param[0] + i)) {
349 			flow = handle_level_irq;
350 			type = IRQ_TYPE_LEVEL_HIGH;
351 		}
352 
353 		irq_domain_set_info(domain, virq + i, fwspec->param[0] + i,
354 				    &apple_port_irqchip, port, flow,
355 				    NULL, NULL);
356 
357 		irq_set_irq_type(virq + i, type);
358 	}
359 
360 	return 0;
361 }
362 
363 static void apple_port_irq_domain_free(struct irq_domain *domain,
364 				       unsigned int virq, unsigned int nr_irqs)
365 {
366 	int i;
367 
368 	for (i = 0; i < nr_irqs; i++) {
369 		struct irq_data *d = irq_domain_get_irq_data(domain, virq + i);
370 
371 		irq_set_handler(virq + i, NULL);
372 		irq_domain_reset_irq_data(d);
373 	}
374 }
375 
376 static const struct irq_domain_ops apple_port_irq_domain_ops = {
377 	.translate	= irq_domain_translate_onecell,
378 	.alloc		= apple_port_irq_domain_alloc,
379 	.free		= apple_port_irq_domain_free,
380 };
381 
382 static void apple_port_irq_handler(struct irq_desc *desc)
383 {
384 	struct apple_pcie_port *port = irq_desc_get_handler_data(desc);
385 	struct irq_chip *chip = irq_desc_get_chip(desc);
386 	unsigned long stat;
387 	int i;
388 
389 	chained_irq_enter(chip, desc);
390 
391 	stat = readl_relaxed(port->base + PORT_INTSTAT);
392 
393 	for_each_set_bit(i, &stat, 32)
394 		generic_handle_domain_irq(port->domain, i);
395 
396 	chained_irq_exit(chip, desc);
397 }
398 
399 static int apple_pcie_port_setup_irq(struct apple_pcie_port *port)
400 {
401 	struct fwnode_handle *fwnode = &port->np->fwnode;
402 	struct apple_pcie *pcie = port->pcie;
403 	unsigned int irq;
404 	u32 val = 0;
405 
406 	/* FIXME: consider moving each interrupt under each port */
407 	irq = irq_of_parse_and_map(to_of_node(dev_fwnode(port->pcie->dev)),
408 				   port->idx);
409 	if (!irq)
410 		return -ENXIO;
411 
412 	port->domain = irq_domain_create_linear(fwnode, 32,
413 						&apple_port_irq_domain_ops,
414 						port);
415 	if (!port->domain)
416 		return -ENOMEM;
417 
418 	/* Disable all interrupts */
419 	writel_relaxed(~0, port->base + PORT_INTMSK);
420 	writel_relaxed(~0, port->base + PORT_INTSTAT);
421 	writel_relaxed(~0, port->base + PORT_LINKCMDSTS);
422 
423 	irq_set_chained_handler_and_data(irq, apple_port_irq_handler, port);
424 
425 	/* Configure MSI base address */
426 	BUILD_BUG_ON(upper_32_bits(DOORBELL_ADDR));
427 	writel_relaxed(lower_32_bits(DOORBELL_ADDR),
428 		       port->base + pcie->hw->port_msiaddr);
429 	if (pcie->hw->port_msiaddr_hi)
430 		writel_relaxed(0, port->base + pcie->hw->port_msiaddr_hi);
431 
432 	/* Enable MSIs, shared between all ports */
433 	if (pcie->hw->port_msimap) {
434 		for (int i = 0; i < pcie->nvecs; i++)
435 			writel_relaxed(FIELD_PREP(PORT_MSIMAP_TARGET, i) |
436 				       PORT_MSIMAP_ENABLE,
437 				       port->base + pcie->hw->port_msimap + 4 * i);
438 	} else {
439 		writel_relaxed(0, port->base + PORT_MSIBASE);
440 		val = ilog2(pcie->nvecs) << PORT_MSICFG_L2MSINUM_SHIFT;
441 	}
442 
443 	writel_relaxed(val | PORT_MSICFG_EN, port->base + PORT_MSICFG);
444 	return 0;
445 }
446 
447 static irqreturn_t apple_pcie_port_irq(int irq, void *data)
448 {
449 	struct apple_pcie_port *port = data;
450 	unsigned int hwirq = irq_domain_get_irq_data(port->domain, irq)->hwirq;
451 
452 	switch (hwirq) {
453 	case PORT_INT_LINK_UP:
454 		dev_info_ratelimited(port->pcie->dev, "Link up on %pOF\n",
455 				     port->np);
456 		complete_all(&port->pcie->event);
457 		break;
458 	case PORT_INT_LINK_DOWN:
459 		dev_info_ratelimited(port->pcie->dev, "Link down on %pOF\n",
460 				     port->np);
461 		break;
462 	default:
463 		return IRQ_NONE;
464 	}
465 
466 	return IRQ_HANDLED;
467 }
468 
469 static int apple_pcie_port_register_irqs(struct apple_pcie_port *port)
470 {
471 	static struct {
472 		unsigned int	hwirq;
473 		const char	*name;
474 	} port_irqs[] = {
475 		{ PORT_INT_LINK_UP,	"Link up",	},
476 		{ PORT_INT_LINK_DOWN,	"Link down",	},
477 	};
478 	int i;
479 
480 	for (i = 0; i < ARRAY_SIZE(port_irqs); i++) {
481 		struct irq_fwspec fwspec = {
482 			.fwnode		= &port->np->fwnode,
483 			.param_count	= 1,
484 			.param		= {
485 				[0]	= port_irqs[i].hwirq,
486 			},
487 		};
488 		unsigned int irq;
489 		int ret;
490 
491 		irq = irq_domain_alloc_irqs(port->domain, 1, NUMA_NO_NODE,
492 					    &fwspec);
493 		if (WARN_ON(!irq))
494 			continue;
495 
496 		ret = request_irq(irq, apple_pcie_port_irq, 0,
497 				  port_irqs[i].name, port);
498 		WARN_ON(ret);
499 	}
500 
501 	return 0;
502 }
503 
504 static int apple_pcie_setup_refclk(struct apple_pcie *pcie,
505 				   struct apple_pcie_port *port)
506 {
507 	u32 stat;
508 	int res;
509 
510 	if (pcie->hw->phy_lane_ctl)
511 		rmw_set(PHY_LANE_CTL_CFGACC, port->phy + pcie->hw->phy_lane_ctl);
512 
513 	rmw_set(PHY_LANE_CFG_REFCLK0REQ, port->phy + PHY_LANE_CFG);
514 
515 	res = readl_relaxed_poll_timeout(port->phy + PHY_LANE_CFG,
516 					 stat, stat & PHY_LANE_CFG_REFCLK0ACK,
517 					 100, 50000);
518 	if (res < 0)
519 		return res;
520 
521 	rmw_set(PHY_LANE_CFG_REFCLK1REQ, port->phy + PHY_LANE_CFG);
522 	res = readl_relaxed_poll_timeout(port->phy + PHY_LANE_CFG,
523 					 stat, stat & PHY_LANE_CFG_REFCLK1ACK,
524 					 100, 50000);
525 
526 	if (res < 0)
527 		return res;
528 
529 	if (pcie->hw->phy_lane_ctl)
530 		rmw_clear(PHY_LANE_CTL_CFGACC, port->phy + pcie->hw->phy_lane_ctl);
531 
532 	rmw_set(PHY_LANE_CFG_REFCLKEN, port->phy + PHY_LANE_CFG);
533 
534 	if (pcie->hw->port_refclk)
535 		rmw_set(PORT_REFCLK_EN, port->base + pcie->hw->port_refclk);
536 
537 	return 0;
538 }
539 
540 static void __iomem *port_rid2sid_addr(struct apple_pcie_port *port, int idx)
541 {
542 	return port->base + port->pcie->hw->port_rid2sid + 4 * idx;
543 }
544 
545 static u32 apple_pcie_rid2sid_write(struct apple_pcie_port *port,
546 				    int idx, u32 val)
547 {
548 	writel_relaxed(val, port_rid2sid_addr(port, idx));
549 	/* Read back to ensure completion of the write */
550 	return readl_relaxed(port_rid2sid_addr(port, idx));
551 }
552 
553 static int apple_pcie_setup_port(struct apple_pcie *pcie,
554 				 struct device_node *np)
555 {
556 	struct platform_device *platform = to_platform_device(pcie->dev);
557 	struct apple_pcie_port *port;
558 	struct gpio_desc *reset;
559 	struct resource *res;
560 	char name[16];
561 	u32 stat, idx;
562 	int ret, i;
563 
564 	reset = devm_fwnode_gpiod_get(pcie->dev, of_fwnode_handle(np), "reset",
565 				      GPIOD_OUT_LOW, "PERST#");
566 	if (IS_ERR(reset))
567 		return PTR_ERR(reset);
568 
569 	port = devm_kzalloc(pcie->dev, sizeof(*port), GFP_KERNEL);
570 	if (!port)
571 		return -ENOMEM;
572 
573 	port->sid_map = devm_bitmap_zalloc(pcie->dev, pcie->hw->max_rid2sid, GFP_KERNEL);
574 	if (!port->sid_map)
575 		return -ENOMEM;
576 
577 	ret = of_property_read_u32_index(np, "reg", 0, &idx);
578 	if (ret)
579 		return ret;
580 
581 	/* Use the first reg entry to work out the port index */
582 	port->idx = idx >> 11;
583 	port->pcie = pcie;
584 	port->np = np;
585 
586 	raw_spin_lock_init(&port->lock);
587 
588 	snprintf(name, sizeof(name), "port%d", port->idx);
589 	res = platform_get_resource_byname(platform, IORESOURCE_MEM, name);
590 	if (!res)
591 		res = platform_get_resource(platform, IORESOURCE_MEM, port->idx + 2);
592 
593 	port->base = devm_ioremap_resource(&platform->dev, res);
594 	if (IS_ERR(port->base))
595 		return PTR_ERR(port->base);
596 
597 	snprintf(name, sizeof(name), "phy%d", port->idx);
598 	res = platform_get_resource_byname(platform, IORESOURCE_MEM, name);
599 	if (res)
600 		port->phy = devm_ioremap_resource(&platform->dev, res);
601 	else
602 		port->phy = pcie->base + CORE_PHY_DEFAULT_BASE(port->idx);
603 
604 	rmw_set(PORT_APPCLK_EN, port->base + PORT_APPCLK);
605 
606 	/* Assert PERST# before setting up the clock */
607 	gpiod_set_value_cansleep(reset, 1);
608 
609 	ret = apple_pcie_setup_refclk(pcie, port);
610 	if (ret < 0)
611 		return ret;
612 
613 	/* The minimal Tperst-clk value is 100us (PCIe CEM r5.0, 2.9.2) */
614 	usleep_range(100, 200);
615 
616 	/* Deassert PERST# */
617 	rmw_set(PORT_PERST_OFF, port->base + pcie->hw->port_perst);
618 	gpiod_set_value_cansleep(reset, 0);
619 
620 	/* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
621 	msleep(100);
622 
623 	ret = readl_relaxed_poll_timeout(port->base + PORT_STATUS, stat,
624 					 stat & PORT_STATUS_READY, 100, 250000);
625 	if (ret < 0) {
626 		dev_err(pcie->dev, "port %pOF ready wait timeout\n", np);
627 		return ret;
628 	}
629 
630 	if (pcie->hw->port_refclk)
631 		rmw_clear(PORT_REFCLK_CGDIS, port->base + pcie->hw->port_refclk);
632 	else
633 		rmw_set(PHY_LANE_CFG_REFCLKCGEN, port->phy + PHY_LANE_CFG);
634 
635 	rmw_clear(PORT_APPCLK_CGDIS, port->base + PORT_APPCLK);
636 
637 	ret = apple_pcie_port_setup_irq(port);
638 	if (ret)
639 		return ret;
640 
641 	/* Reset all RID/SID mappings, and check for RAZ/WI registers */
642 	for (i = 0; i < pcie->hw->max_rid2sid; i++) {
643 		if (apple_pcie_rid2sid_write(port, i, 0xbad1d) != 0xbad1d)
644 			break;
645 		apple_pcie_rid2sid_write(port, i, 0);
646 	}
647 
648 	dev_dbg(pcie->dev, "%pOF: %d RID/SID mapping entries\n", np, i);
649 
650 	port->sid_map_sz = i;
651 
652 	list_add_tail(&port->entry, &pcie->ports);
653 	init_completion(&pcie->event);
654 
655 	/* In the success path, we keep a reference to np around */
656 	of_node_get(np);
657 
658 	ret = apple_pcie_port_register_irqs(port);
659 	WARN_ON(ret);
660 
661 	writel_relaxed(PORT_LTSSMCTL_START, port->base + PORT_LTSSMCTL);
662 
663 	if (!wait_for_completion_timeout(&pcie->event, HZ / 10))
664 		dev_warn(pcie->dev, "%pOF link didn't come up\n", np);
665 
666 	return 0;
667 }
668 
669 static const struct msi_parent_ops apple_msi_parent_ops = {
670 	.supported_flags	= (MSI_GENERIC_FLAGS_MASK	|
671 				   MSI_FLAG_PCI_MSIX		|
672 				   MSI_FLAG_MULTI_PCI_MSI),
673 	.required_flags		= (MSI_FLAG_USE_DEF_DOM_OPS	|
674 				   MSI_FLAG_USE_DEF_CHIP_OPS	|
675 				   MSI_FLAG_PCI_MSI_MASK_PARENT),
676 	.chip_flags		= MSI_CHIP_FLAG_SET_EOI,
677 	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
678 	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
679 };
680 
681 static int apple_msi_init(struct apple_pcie *pcie)
682 {
683 	struct fwnode_handle *fwnode = dev_fwnode(pcie->dev);
684 	struct irq_domain_info info = {
685 		.fwnode		= fwnode,
686 		.ops		= &apple_msi_domain_ops,
687 		.size		= pcie->nvecs,
688 		.host_data	= pcie,
689 	};
690 	struct of_phandle_args args = {};
691 	int ret;
692 
693 	ret = of_parse_phandle_with_args(to_of_node(fwnode), "msi-ranges",
694 					 "#interrupt-cells", 0, &args);
695 	if (ret)
696 		return ret;
697 
698 	ret = of_property_read_u32_index(to_of_node(fwnode), "msi-ranges",
699 					 args.args_count + 1, &pcie->nvecs);
700 	if (ret)
701 		return ret;
702 
703 	of_phandle_args_to_fwspec(args.np, args.args, args.args_count,
704 				  &pcie->fwspec);
705 
706 	pcie->bitmap = devm_bitmap_zalloc(pcie->dev, pcie->nvecs, GFP_KERNEL);
707 	if (!pcie->bitmap)
708 		return -ENOMEM;
709 
710 	info.parent = irq_find_matching_fwspec(&pcie->fwspec, DOMAIN_BUS_WIRED);
711 	if (!info.parent) {
712 		dev_err(pcie->dev, "failed to find parent domain\n");
713 		return -ENXIO;
714 	}
715 
716 	if (!msi_create_parent_irq_domain(&info, &apple_msi_parent_ops)) {
717 		dev_err(pcie->dev, "failed to create IRQ domain\n");
718 		return -ENOMEM;
719 	}
720 	return 0;
721 }
722 
723 static struct apple_pcie_port *apple_pcie_get_port(struct pci_dev *pdev)
724 {
725 	struct pci_config_window *cfg = pdev->sysdata;
726 	struct apple_pcie *pcie = cfg->priv;
727 	struct pci_dev *port_pdev;
728 	struct apple_pcie_port *port;
729 
730 	/* Find the root port this device is on */
731 	port_pdev = pcie_find_root_port(pdev);
732 
733 	/* If finding the port itself, nothing to do */
734 	if (WARN_ON(!port_pdev) || pdev == port_pdev)
735 		return NULL;
736 
737 	list_for_each_entry(port, &pcie->ports, entry) {
738 		if (port->idx == PCI_SLOT(port_pdev->devfn))
739 			return port;
740 	}
741 
742 	return NULL;
743 }
744 
745 static int apple_pcie_enable_device(struct pci_host_bridge *bridge, struct pci_dev *pdev)
746 {
747 	u32 sid, rid = pci_dev_id(pdev);
748 	struct apple_pcie_port *port;
749 	int idx, err;
750 
751 	port = apple_pcie_get_port(pdev);
752 	if (!port)
753 		return 0;
754 
755 	dev_dbg(&pdev->dev, "added to bus %s, index %d\n",
756 		pci_name(pdev->bus->self), port->idx);
757 
758 	err = of_map_id(port->pcie->dev->of_node, rid, "iommu-map",
759 			"iommu-map-mask", NULL, &sid);
760 	if (err)
761 		return err;
762 
763 	mutex_lock(&port->pcie->lock);
764 
765 	idx = bitmap_find_free_region(port->sid_map, port->sid_map_sz, 0);
766 	if (idx >= 0) {
767 		apple_pcie_rid2sid_write(port, idx,
768 					 PORT_RID2SID_VALID |
769 					 (sid << PORT_RID2SID_SID_SHIFT) | rid);
770 
771 		dev_dbg(&pdev->dev, "mapping RID%x to SID%x (index %d)\n",
772 			rid, sid, idx);
773 	}
774 
775 	mutex_unlock(&port->pcie->lock);
776 
777 	return idx >= 0 ? 0 : -ENOSPC;
778 }
779 
780 static void apple_pcie_disable_device(struct pci_host_bridge *bridge, struct pci_dev *pdev)
781 {
782 	struct apple_pcie_port *port;
783 	u32 rid = pci_dev_id(pdev);
784 	int idx;
785 
786 	port = apple_pcie_get_port(pdev);
787 	if (!port)
788 		return;
789 
790 	mutex_lock(&port->pcie->lock);
791 
792 	for_each_set_bit(idx, port->sid_map, port->sid_map_sz) {
793 		u32 val;
794 
795 		val = readl_relaxed(port_rid2sid_addr(port, idx));
796 		if ((val & 0xffff) == rid) {
797 			apple_pcie_rid2sid_write(port, idx, 0);
798 			bitmap_release_region(port->sid_map, idx, 0);
799 			dev_dbg(&pdev->dev, "Released %x (%d)\n", val, idx);
800 			break;
801 		}
802 	}
803 
804 	mutex_unlock(&port->pcie->lock);
805 }
806 
807 static int apple_pcie_init(struct pci_config_window *cfg)
808 {
809 	struct apple_pcie *pcie = cfg->priv;
810 	struct device *dev = cfg->parent;
811 	int ret;
812 
813 	for_each_available_child_of_node_scoped(dev->of_node, of_port) {
814 		ret = apple_pcie_setup_port(pcie, of_port);
815 		if (ret) {
816 			dev_err(dev, "Port %pOF setup fail: %d\n", of_port, ret);
817 			return ret;
818 		}
819 	}
820 
821 	return 0;
822 }
823 
824 static const struct pci_ecam_ops apple_pcie_cfg_ecam_ops = {
825 	.init		= apple_pcie_init,
826 	.enable_device	= apple_pcie_enable_device,
827 	.disable_device	= apple_pcie_disable_device,
828 	.pci_ops	= {
829 		.map_bus	= pci_ecam_map_bus,
830 		.read		= pci_generic_config_read,
831 		.write		= pci_generic_config_write,
832 	}
833 };
834 
835 static int apple_pcie_probe(struct platform_device *pdev)
836 {
837 	struct device *dev = &pdev->dev;
838 	struct apple_pcie *pcie;
839 	int ret;
840 
841 	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
842 	if (!pcie)
843 		return -ENOMEM;
844 
845 	pcie->dev = dev;
846 	pcie->hw = of_device_get_match_data(dev);
847 	if (!pcie->hw)
848 		return -ENODEV;
849 	pcie->base = devm_platform_ioremap_resource(pdev, 1);
850 	if (IS_ERR(pcie->base))
851 		return PTR_ERR(pcie->base);
852 
853 	mutex_init(&pcie->lock);
854 	INIT_LIST_HEAD(&pcie->ports);
855 	dev_set_drvdata(dev, pcie);
856 
857 	ret = apple_msi_init(pcie);
858 	if (ret)
859 		return ret;
860 
861 	return pci_host_common_init(pdev, &apple_pcie_cfg_ecam_ops);
862 }
863 
864 static const struct of_device_id apple_pcie_of_match[] = {
865 	{ .compatible = "apple,t6020-pcie",	.data = &t602x_hw },
866 	{ .compatible = "apple,pcie",		.data = &t8103_hw },
867 	{ }
868 };
869 MODULE_DEVICE_TABLE(of, apple_pcie_of_match);
870 
871 static struct platform_driver apple_pcie_driver = {
872 	.probe	= apple_pcie_probe,
873 	.driver	= {
874 		.name			= "pcie-apple",
875 		.of_match_table		= apple_pcie_of_match,
876 		.suppress_bind_attrs	= true,
877 	},
878 };
879 module_platform_driver(apple_pcie_driver);
880 
881 MODULE_DESCRIPTION("Apple PCIe host bridge driver");
882 MODULE_LICENSE("GPL v2");
883