summaryrefslogtreecommitdiff
path: root/drivers/pci/controller/pcie-rockchip-ep.c
blob: 1362745336568ec8bd1b2736b2579c2bf519f6f6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
// SPDX-License-Identifier: GPL-2.0+
/*
 * Rockchip AXI PCIe endpoint controller driver
 *
 * Copyright (c) 2018 Rockchip, Inc.
 *
 * Author: Shawn Lin <shawn.lin@rock-chips.com>
 *         Simon Xue <xxm@rock-chips.com>
 */

#include <linux/configfs.h>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/pci-epc.h>
#include <linux/platform_device.h>
#include <linux/pci-epf.h>
#include <linux/sizes.h>

#include "pcie-rockchip.h"

/**
 * struct rockchip_pcie_ep - private data for PCIe endpoint controller driver
 * @rockchip: Rockchip PCIe controller
 * @epc: PCI EPC device
 * @max_regions: maximum number of regions supported by hardware
 * @ob_region_map: bitmask of mapped outbound regions
 * @ob_addr: base addresses in the AXI bus where the outbound regions start
 * @irq_phys_addr: base address on the AXI bus where the MSI/INTX IRQ
 *		   dedicated outbound regions is mapped.
 * @irq_cpu_addr: base address in the CPU space where a write access triggers
 *		  the sending of a memory write (MSI) / normal message (INTX
 *		  IRQ) TLP through the PCIe bus.
 * @irq_pci_addr: used to save the current mapping of the MSI/INTX IRQ
 *		  dedicated outbound region.
 * @irq_pci_fn: the latest PCI function that has updated the mapping of
 *		the MSI/INTX IRQ dedicated outbound region.
 * @irq_pending: bitmask of asserted INTX IRQs.
 */
struct rockchip_pcie_ep {
	struct rockchip_pcie	rockchip;
	struct pci_epc		*epc;
	u32			max_regions;
	unsigned long		ob_region_map;
	phys_addr_t		*ob_addr;
	phys_addr_t		irq_phys_addr;
	void __iomem		*irq_cpu_addr;
	u64			irq_pci_addr;
	u8			irq_pci_fn;
	u8			irq_pending;
};

static void rockchip_pcie_clear_ep_ob_atu(struct rockchip_pcie *rockchip,
					  u32 region)
{
	rockchip_pcie_write(rockchip, 0,
			    ROCKCHIP_PCIE_AT_OB_REGION_PCI_ADDR0(region));
	rockchip_pcie_write(rockchip, 0,
			    ROCKCHIP_PCIE_AT_OB_REGION_PCI_ADDR1(region));
	rockchip_pcie_write(rockchip, 0,
			    ROCKCHIP_PCIE_AT_OB_REGION_DESC0(region));
	rockchip_pcie_write(rockchip, 0,
			    ROCKCHIP_PCIE_AT_OB_REGION_DESC1(region));
}

static void rockchip_pcie_prog_ep_ob_atu(struct rockchip_pcie *rockchip, u8 fn,
					 u32 r, u64 cpu_addr, u64 pci_addr,
					 size_t size)
{
	int num_pass_bits = fls64(size - 1);
	u32 addr0, addr1, desc0;

	if (num_pass_bits < 8)
		num_pass_bits = 8;

	addr0 = ((num_pass_bits - 1) & PCIE_CORE_OB_REGION_ADDR0_NUM_BITS) |
		(lower_32_bits(pci_addr) & PCIE_CORE_OB_REGION_ADDR0_LO_ADDR);
	addr1 = upper_32_bits(pci_addr);
	desc0 = ROCKCHIP_PCIE_AT_OB_REGION_DESC0_DEVFN(fn) | AXI_WRAPPER_MEM_WRITE;

	/* PCI bus address region */
	rockchip_pcie_write(rockchip, addr0,
			    ROCKCHIP_PCIE_AT_OB_REGION_PCI_ADDR0(r));
	rockchip_pcie_write(rockchip, addr1,
			    ROCKCHIP_PCIE_AT_OB_REGION_PCI_ADDR1(r));
	rockchip_pcie_write(rockchip, desc0,
			    ROCKCHIP_PCIE_AT_OB_REGION_DESC0(r));
	rockchip_pcie_write(rockchip, 0,
			    ROCKCHIP_PCIE_AT_OB_REGION_DESC1(r));
}

static int rockchip_pcie_ep_write_header(struct pci_epc *epc, u8 fn, u8 vfn,
					 struct pci_epf_header *hdr)
{
	u32 reg;
	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
	struct rockchip_pcie *rockchip = &ep->rockchip;

	/* All functions share the same vendor ID with function 0 */
	if (fn == 0) {
		rockchip_pcie_write(rockchip,
				    hdr->vendorid | hdr->subsys_vendor_id << 16,
				    PCIE_CORE_CONFIG_VENDOR);
	}

	reg = rockchip_pcie_read(rockchip, PCIE_EP_CONFIG_DID_VID);
	reg = (reg & 0xFFFF) | (hdr->deviceid << 16);
	rockchip_pcie_write(rockchip, reg, PCIE_EP_CONFIG_DID_VID);

	rockchip_pcie_write(rockchip,
			    hdr->revid |
			    hdr->progif_code << 8 |
			    hdr->subclass_code << 16 |
			    hdr->baseclass_code << 24,
			    ROCKCHIP_PCIE_EP_FUNC_BASE(fn) + PCI_REVISION_ID);
	rockchip_pcie_write(rockchip, hdr->cache_line_size,
			    ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
			    PCI_CACHE_LINE_SIZE);
	rockchip_pcie_write(rockchip, hdr->subsys_id << 16,
			    ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
			    PCI_SUBSYSTEM_VENDOR_ID);
	rockchip_pcie_write(rockchip, hdr->interrupt_pin << 8,
			    ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
			    PCI_INTERRUPT_LINE);

	return 0;
}

static int rockchip_pcie_ep_set_bar(struct pci_epc *epc, u8 fn, u8 vfn,
				    struct pci_epf_bar *epf_bar)
{
	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
	struct rockchip_pcie *rockchip = &ep->rockchip;
	dma_addr_t bar_phys = epf_bar->phys_addr;
	enum pci_barno bar = epf_bar->barno;
	int flags = epf_bar->flags;
	u32 addr0, addr1, reg, cfg, b, aperture, ctrl;
	u64 sz;

	/* BAR size is 2^(aperture + 7) */
	sz = max_t(size_t, epf_bar->size, MIN_EP_APERTURE);

	/*
	 * roundup_pow_of_two() returns an unsigned long, which is not suited
	 * for 64bit values.
	 */
	sz = 1ULL << fls64(sz - 1);
	aperture = ilog2(sz) - 7; /* 128B -> 0, 256B -> 1, 512B -> 2, ... */

	if ((flags & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) {
		ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_IO_32BITS;
	} else {
		bool is_prefetch = !!(flags & PCI_BASE_ADDRESS_MEM_PREFETCH);
		bool is_64bits = !!(flags & PCI_BASE_ADDRESS_MEM_TYPE_64);

		if (is_64bits && (bar & 1))
			return -EINVAL;

		if (is_64bits && is_prefetch)
			ctrl =
			    ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_PREFETCH_MEM_64BITS;
		else if (is_prefetch)
			ctrl =
			    ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_PREFETCH_MEM_32BITS;
		else if (is_64bits)
			ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_MEM_64BITS;
		else
			ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_MEM_32BITS;
	}

	if (bar < BAR_4) {
		reg = ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG0(fn);
		b = bar;
	} else {
		reg = ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG1(fn);
		b = bar - BAR_4;
	}

	addr0 = lower_32_bits(bar_phys);
	addr1 = upper_32_bits(bar_phys);

	cfg = rockchip_pcie_read(rockchip, reg);
	cfg &= ~(ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) |
		 ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG_BAR_CTRL_MASK(b));
	cfg |= (ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG_BAR_APERTURE(b, aperture) |
		ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG_BAR_CTRL(b, ctrl));

	rockchip_pcie_write(rockchip, cfg, reg);
	rockchip_pcie_write(rockchip, addr0,
			    ROCKCHIP_PCIE_AT_IB_EP_FUNC_BAR_ADDR0(fn, bar));
	rockchip_pcie_write(rockchip, addr1,
			    ROCKCHIP_PCIE_AT_IB_EP_FUNC_BAR_ADDR1(fn, bar));

	return 0;
}

static void rockchip_pcie_ep_clear_bar(struct pci_epc *epc, u8 fn, u8 vfn,
				       struct pci_epf_bar *epf_bar)
{
	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
	struct rockchip_pcie *rockchip = &ep->rockchip;
	u32 reg, cfg, b, ctrl;
	enum pci_barno bar = epf_bar->barno;

	if (bar < BAR_4) {
		reg = ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG0(fn);
		b = bar;
	} else {
		reg = ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG1(fn);
		b = bar - BAR_4;
	}

	ctrl = ROCKCHIP_PCIE_CORE_BAR_CFG_CTRL_DISABLED;
	cfg = rockchip_pcie_read(rockchip, reg);
	cfg &= ~(ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG_BAR_APERTURE_MASK(b) |
		 ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG_BAR_CTRL_MASK(b));
	cfg |= ROCKCHIP_PCIE_CORE_EP_FUNC_BAR_CFG_BAR_CTRL(b, ctrl);

	rockchip_pcie_write(rockchip, cfg, reg);
	rockchip_pcie_write(rockchip, 0x0,
			    ROCKCHIP_PCIE_AT_IB_EP_FUNC_BAR_ADDR0(fn, bar));
	rockchip_pcie_write(rockchip, 0x0,
			    ROCKCHIP_PCIE_AT_IB_EP_FUNC_BAR_ADDR1(fn, bar));
}

static inline u32 rockchip_ob_region(phys_addr_t addr)
{
	return (addr >> ilog2(SZ_1M)) & 0x1f;
}

static int rockchip_pcie_ep_map_addr(struct pci_epc *epc, u8 fn, u8 vfn,
				     phys_addr_t addr, u64 pci_addr,
				     size_t size)
{
	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
	struct rockchip_pcie *pcie = &ep->rockchip;
	u32 r = rockchip_ob_region(addr);

	rockchip_pcie_prog_ep_ob_atu(pcie, fn, r, addr, pci_addr, size);

	set_bit(r, &ep->ob_region_map);
	ep->ob_addr[r] = addr;

	return 0;
}

static void rockchip_pcie_ep_unmap_addr(struct pci_epc *epc, u8 fn, u8 vfn,
					phys_addr_t addr)
{
	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
	struct rockchip_pcie *rockchip = &ep->rockchip;
	u32 r;

	for (r = 0; r < ep->max_regions; r++)
		if (ep->ob_addr[r] == addr)
			break;

	if (r == ep->max_regions)
		return;

	rockchip_pcie_clear_ep_ob_atu(rockchip, r);

	ep->ob_addr[r] = 0;
	clear_bit(r, &ep->ob_region_map);
}

static int rockchip_pcie_ep_set_msi(struct pci_epc *epc, u8 fn, u8 vfn,
				    u8 multi_msg_cap)
{
	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
	struct rockchip_pcie *rockchip = &ep->rockchip;
	u32 flags;

	flags = rockchip_pcie_read(rockchip,
				   ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
				   ROCKCHIP_PCIE_EP_MSI_CTRL_REG);
	flags &= ~ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_MASK;
	flags |=
	   (multi_msg_cap << ROCKCHIP_PCIE_EP_MSI_CTRL_MMC_OFFSET) |
	   (PCI_MSI_FLAGS_64BIT << ROCKCHIP_PCIE_EP_MSI_FLAGS_OFFSET);
	flags &= ~ROCKCHIP_PCIE_EP_MSI_CTRL_MASK_MSI_CAP;
	rockchip_pcie_write(rockchip, flags,
			    ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
			    ROCKCHIP_PCIE_EP_MSI_CTRL_REG);
	return 0;
}

static int rockchip_pcie_ep_get_msi(struct pci_epc *epc, u8 fn, u8 vfn)
{
	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
	struct rockchip_pcie *rockchip = &ep->rockchip;
	u32 flags;

	flags = rockchip_pcie_read(rockchip,
				   ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
				   ROCKCHIP_PCIE_EP_MSI_CTRL_REG);
	if (!(flags & ROCKCHIP_PCIE_EP_MSI_CTRL_ME))
		return -EINVAL;

	return ((flags & ROCKCHIP_PCIE_EP_MSI_CTRL_MME_MASK) >>
			ROCKCHIP_PCIE_EP_MSI_CTRL_MME_OFFSET);
}

static void rockchip_pcie_ep_assert_intx(struct rockchip_pcie_ep *ep, u8 fn,
					 u8 intx, bool do_assert)
{
	struct rockchip_pcie *rockchip = &ep->rockchip;

	intx &= 3;

	if (do_assert) {
		ep->irq_pending |= BIT(intx);
		rockchip_pcie_write(rockchip,
				    PCIE_CLIENT_INT_IN_ASSERT |
				    PCIE_CLIENT_INT_PEND_ST_PEND,
				    PCIE_CLIENT_LEGACY_INT_CTRL);
	} else {
		ep->irq_pending &= ~BIT(intx);
		rockchip_pcie_write(rockchip,
				    PCIE_CLIENT_INT_IN_DEASSERT |
				    PCIE_CLIENT_INT_PEND_ST_NORMAL,
				    PCIE_CLIENT_LEGACY_INT_CTRL);
	}
}

static int rockchip_pcie_ep_send_intx_irq(struct rockchip_pcie_ep *ep, u8 fn,
					  u8 intx)
{
	u16 cmd;

	cmd = rockchip_pcie_read(&ep->rockchip,
				 ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
				 ROCKCHIP_PCIE_EP_CMD_STATUS);

	if (cmd & PCI_COMMAND_INTX_DISABLE)
		return -EINVAL;

	/*
	 * Should add some delay between toggling INTx per TRM vaguely saying
	 * it depends on some cycles of the AHB bus clock to function it. So
	 * add sufficient 1ms here.
	 */
	rockchip_pcie_ep_assert_intx(ep, fn, intx, true);
	mdelay(1);
	rockchip_pcie_ep_assert_intx(ep, fn, intx, false);
	return 0;
}

static int rockchip_pcie_ep_send_msi_irq(struct rockchip_pcie_ep *ep, u8 fn,
					 u8 interrupt_num)
{
	struct rockchip_pcie *rockchip = &ep->rockchip;
	u32 flags, mme, data, data_mask;
	u8 msi_count;
	u64 pci_addr;
	u32 r;

	/* Check MSI enable bit */
	flags = rockchip_pcie_read(&ep->rockchip,
				   ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
				   ROCKCHIP_PCIE_EP_MSI_CTRL_REG);
	if (!(flags & ROCKCHIP_PCIE_EP_MSI_CTRL_ME))
		return -EINVAL;

	/* Get MSI numbers from MME */
	mme = ((flags & ROCKCHIP_PCIE_EP_MSI_CTRL_MME_MASK) >>
			ROCKCHIP_PCIE_EP_MSI_CTRL_MME_OFFSET);
	msi_count = 1 << mme;
	if (!interrupt_num || interrupt_num > msi_count)
		return -EINVAL;

	/* Set MSI private data */
	data_mask = msi_count - 1;
	data = rockchip_pcie_read(rockchip,
				  ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
				  ROCKCHIP_PCIE_EP_MSI_CTRL_REG +
				  PCI_MSI_DATA_64);
	data = (data & ~data_mask) | ((interrupt_num - 1) & data_mask);

	/* Get MSI PCI address */
	pci_addr = rockchip_pcie_read(rockchip,
				      ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
				      ROCKCHIP_PCIE_EP_MSI_CTRL_REG +
				      PCI_MSI_ADDRESS_HI);
	pci_addr <<= 32;
	pci_addr |= rockchip_pcie_read(rockchip,
				       ROCKCHIP_PCIE_EP_FUNC_BASE(fn) +
				       ROCKCHIP_PCIE_EP_MSI_CTRL_REG +
				       PCI_MSI_ADDRESS_LO);

	/* Set the outbound region if needed. */
	if (unlikely(ep->irq_pci_addr != (pci_addr & PCIE_ADDR_MASK) ||
		     ep->irq_pci_fn != fn)) {
		r = rockchip_ob_region(ep->irq_phys_addr);
		rockchip_pcie_prog_ep_ob_atu(rockchip, fn, r,
					     ep->irq_phys_addr,
					     pci_addr & PCIE_ADDR_MASK,
					     ~PCIE_ADDR_MASK + 1);
		ep->irq_pci_addr = (pci_addr & PCIE_ADDR_MASK);
		ep->irq_pci_fn = fn;
	}

	writew(data, ep->irq_cpu_addr + (pci_addr & ~PCIE_ADDR_MASK));
	return 0;
}

static int rockchip_pcie_ep_raise_irq(struct pci_epc *epc, u8 fn, u8 vfn,
				      unsigned int type, u16 interrupt_num)
{
	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);

	switch (type) {
	case PCI_IRQ_INTX:
		return rockchip_pcie_ep_send_intx_irq(ep, fn, 0);
	case PCI_IRQ_MSI:
		return rockchip_pcie_ep_send_msi_irq(ep, fn, interrupt_num);
	default:
		return -EINVAL;
	}
}

static int rockchip_pcie_ep_start(struct pci_epc *epc)
{
	struct rockchip_pcie_ep *ep = epc_get_drvdata(epc);
	struct rockchip_pcie *rockchip = &ep->rockchip;
	struct pci_epf *epf;
	u32 cfg;

	cfg = BIT(0);
	list_for_each_entry(epf, &epc->pci_epf, list)
		cfg |= BIT(epf->func_no);

	rockchip_pcie_write(rockchip, cfg, PCIE_CORE_PHY_FUNC_CFG);

	return 0;
}

static const struct pci_epc_features rockchip_pcie_epc_features = {
	.linkup_notifier = false,
	.msi_capable = true,
	.msix_capable = false,
	.align = 256,
};

static const struct pci_epc_features*
rockchip_pcie_ep_get_features(struct pci_epc *epc, u8 func_no, u8 vfunc_no)
{
	return &rockchip_pcie_epc_features;
}

static const struct pci_epc_ops rockchip_pcie_epc_ops = {
	.write_header	= rockchip_pcie_ep_write_header,
	.set_bar	= rockchip_pcie_ep_set_bar,
	.clear_bar	= rockchip_pcie_ep_clear_bar,
	.map_addr	= rockchip_pcie_ep_map_addr,
	.unmap_addr	= rockchip_pcie_ep_unmap_addr,
	.set_msi	= rockchip_pcie_ep_set_msi,
	.get_msi	= rockchip_pcie_ep_get_msi,
	.raise_irq	= rockchip_pcie_ep_raise_irq,
	.start		= rockchip_pcie_ep_start,
	.get_features	= rockchip_pcie_ep_get_features,
};

static int rockchip_pcie_parse_ep_dt(struct rockchip_pcie *rockchip,
				     struct rockchip_pcie_ep *ep)
{
	struct device *dev = rockchip->dev;
	int err;

	err = rockchip_pcie_parse_dt(rockchip);
	if (err)
		return err;

	err = rockchip_pcie_get_phys(rockchip);
	if (err)
		return err;

	err = of_property_read_u32(dev->of_node,
				   "rockchip,max-outbound-regions",
				   &ep->max_regions);
	if (err < 0 || ep->max_regions > MAX_REGION_LIMIT)
		ep->max_regions = MAX_REGION_LIMIT;

	ep->ob_region_map = 0;

	err = of_property_read_u8(dev->of_node, "max-functions",
				  &ep->epc->max_functions);
	if (err < 0)
		ep->epc->max_functions = 1;

	return 0;
}

static const struct of_device_id rockchip_pcie_ep_of_match[] = {
	{ .compatible = "rockchip,rk3399-pcie-ep"},
	{},
};

static int rockchip_pcie_ep_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct rockchip_pcie_ep *ep;
	struct rockchip_pcie *rockchip;
	struct pci_epc *epc;
	size_t max_regions;
	struct pci_epc_mem_window *windows = NULL;
	int err, i;
	u32 cfg_msi, cfg_msix_cp;

	ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);
	if (!ep)
		return -ENOMEM;

	rockchip = &ep->rockchip;
	rockchip->is_rc = false;
	rockchip->dev = dev;

	epc = devm_pci_epc_create(dev, &rockchip_pcie_epc_ops);
	if (IS_ERR(epc)) {
		dev_err(dev, "failed to create epc device\n");
		return PTR_ERR(epc);
	}

	ep->epc = epc;
	epc_set_drvdata(epc, ep);

	err = rockchip_pcie_parse_ep_dt(rockchip, ep);
	if (err)
		return err;

	err = rockchip_pcie_enable_clocks(rockchip);
	if (err)
		return err;

	err = rockchip_pcie_init_port(rockchip);
	if (err)
		goto err_disable_clocks;

	/* Establish the link automatically */
	rockchip_pcie_write(rockchip, PCIE_CLIENT_LINK_TRAIN_ENABLE,
			    PCIE_CLIENT_CONFIG);

	max_regions = ep->max_regions;
	ep->ob_addr = devm_kcalloc(dev, max_regions, sizeof(*ep->ob_addr),
				   GFP_KERNEL);

	if (!ep->ob_addr) {
		err = -ENOMEM;
		goto err_uninit_port;
	}

	/* Only enable function 0 by default */
	rockchip_pcie_write(rockchip, BIT(0), PCIE_CORE_PHY_FUNC_CFG);

	windows = devm_kcalloc(dev, ep->max_regions,
			       sizeof(struct pci_epc_mem_window), GFP_KERNEL);
	if (!windows) {
		err = -ENOMEM;
		goto err_uninit_port;
	}
	for (i = 0; i < ep->max_regions; i++) {
		windows[i].phys_base = rockchip->mem_res->start + (SZ_1M * i);
		windows[i].size = SZ_1M;
		windows[i].page_size = SZ_1M;
	}
	err = pci_epc_multi_mem_init(epc, windows, ep->max_regions);
	devm_kfree(dev, windows);

	if (err < 0) {
		dev_err(dev, "failed to initialize the memory space\n");
		goto err_uninit_port;
	}

	ep->irq_cpu_addr = pci_epc_mem_alloc_addr(epc, &ep->irq_phys_addr,
						  SZ_1M);
	if (!ep->irq_cpu_addr) {
		dev_err(dev, "failed to reserve memory space for MSI\n");
		err = -ENOMEM;
		goto err_epc_mem_exit;
	}

	ep->irq_pci_addr = ROCKCHIP_PCIE_EP_DUMMY_IRQ_ADDR;

	/*
	 * MSI-X is not supported but the controller still advertises the MSI-X
	 * capability by default, which can lead to the Root Complex side
	 * allocating MSI-X vectors which cannot be used. Avoid this by skipping
	 * the MSI-X capability entry in the PCIe capabilities linked-list: get
	 * the next pointer from the MSI-X entry and set that in the MSI
	 * capability entry (which is the previous entry). This way the MSI-X
	 * entry is skipped (left out of the linked-list) and not advertised.
	 */
	cfg_msi = rockchip_pcie_read(rockchip, PCIE_EP_CONFIG_BASE +
				     ROCKCHIP_PCIE_EP_MSI_CTRL_REG);

	cfg_msi &= ~ROCKCHIP_PCIE_EP_MSI_CP1_MASK;

	cfg_msix_cp = rockchip_pcie_read(rockchip, PCIE_EP_CONFIG_BASE +
					 ROCKCHIP_PCIE_EP_MSIX_CAP_REG) &
					 ROCKCHIP_PCIE_EP_MSIX_CAP_CP_MASK;

	cfg_msi |= cfg_msix_cp;

	rockchip_pcie_write(rockchip, cfg_msi,
			    PCIE_EP_CONFIG_BASE + ROCKCHIP_PCIE_EP_MSI_CTRL_REG);

	rockchip_pcie_write(rockchip, PCIE_CLIENT_CONF_ENABLE,
			    PCIE_CLIENT_CONFIG);

	pci_epc_init_notify(epc);

	return 0;
err_epc_mem_exit:
	pci_epc_mem_exit(epc);
err_uninit_port:
	rockchip_pcie_deinit_phys(rockchip);
err_disable_clocks:
	rockchip_pcie_disable_clocks(rockchip);
	return err;
}

static struct platform_driver rockchip_pcie_ep_driver = {
	.driver = {
		.name = "rockchip-pcie-ep",
		.of_match_table = rockchip_pcie_ep_of_match,
	},
	.probe = rockchip_pcie_ep_probe,
};

builtin_platform_driver(rockchip_pcie_ep_driver);