summaryrefslogtreecommitdiff
path: root/drivers/pci/host/pcie-iproc.c
blob: e167b2f0098d687c6a197b49e2b86e56dded9514 (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
/*
 * Copyright (C) 2014 Hauke Mehrtens <hauke@hauke-m.de>
 * Copyright (C) 2015 Broadcom Corporation
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation version 2.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/msi.h>
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/mbus.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/phy/phy.h>

#include "pcie-iproc.h"

#define EP_PERST_SOURCE_SELECT_SHIFT 2
#define EP_PERST_SOURCE_SELECT       BIT(EP_PERST_SOURCE_SELECT_SHIFT)
#define EP_MODE_SURVIVE_PERST_SHIFT  1
#define EP_MODE_SURVIVE_PERST        BIT(EP_MODE_SURVIVE_PERST_SHIFT)
#define RC_PCIE_RST_OUTPUT_SHIFT     0
#define RC_PCIE_RST_OUTPUT           BIT(RC_PCIE_RST_OUTPUT_SHIFT)
#define PAXC_RESET_MASK              0x7f

#define CFG_IND_ADDR_MASK            0x00001ffc

#define CFG_ADDR_BUS_NUM_SHIFT       20
#define CFG_ADDR_BUS_NUM_MASK        0x0ff00000
#define CFG_ADDR_DEV_NUM_SHIFT       15
#define CFG_ADDR_DEV_NUM_MASK        0x000f8000
#define CFG_ADDR_FUNC_NUM_SHIFT      12
#define CFG_ADDR_FUNC_NUM_MASK       0x00007000
#define CFG_ADDR_REG_NUM_SHIFT       2
#define CFG_ADDR_REG_NUM_MASK        0x00000ffc
#define CFG_ADDR_CFG_TYPE_SHIFT      0
#define CFG_ADDR_CFG_TYPE_MASK       0x00000003

#define SYS_RC_INTX_MASK             0xf

#define PCIE_PHYLINKUP_SHIFT         3
#define PCIE_PHYLINKUP               BIT(PCIE_PHYLINKUP_SHIFT)
#define PCIE_DL_ACTIVE_SHIFT         2
#define PCIE_DL_ACTIVE               BIT(PCIE_DL_ACTIVE_SHIFT)

#define OARR_VALID_SHIFT             0
#define OARR_VALID                   BIT(OARR_VALID_SHIFT)
#define OARR_SIZE_CFG_SHIFT          1
#define OARR_SIZE_CFG                BIT(OARR_SIZE_CFG_SHIFT)

#define MAX_NUM_OB_WINDOWS           2

#define IPROC_PCIE_REG_INVALID 0xffff

enum iproc_pcie_reg {
	IPROC_PCIE_CLK_CTRL = 0,
	IPROC_PCIE_CFG_IND_ADDR,
	IPROC_PCIE_CFG_IND_DATA,
	IPROC_PCIE_CFG_ADDR,
	IPROC_PCIE_CFG_DATA,
	IPROC_PCIE_INTX_EN,
	IPROC_PCIE_OARR_LO,
	IPROC_PCIE_OARR_HI,
	IPROC_PCIE_OMAP_LO,
	IPROC_PCIE_OMAP_HI,
	IPROC_PCIE_LINK_STATUS,
};

/* iProc PCIe PAXB registers */
static const u16 iproc_pcie_reg_paxb[] = {
	[IPROC_PCIE_CLK_CTRL]     = 0x000,
	[IPROC_PCIE_CFG_IND_ADDR] = 0x120,
	[IPROC_PCIE_CFG_IND_DATA] = 0x124,
	[IPROC_PCIE_CFG_ADDR]     = 0x1f8,
	[IPROC_PCIE_CFG_DATA]     = 0x1fc,
	[IPROC_PCIE_INTX_EN]      = 0x330,
	[IPROC_PCIE_OARR_LO]      = 0xd20,
	[IPROC_PCIE_OARR_HI]      = 0xd24,
	[IPROC_PCIE_OMAP_LO]      = 0xd40,
	[IPROC_PCIE_OMAP_HI]      = 0xd44,
	[IPROC_PCIE_LINK_STATUS]  = 0xf0c,
};

/* iProc PCIe PAXC v1 registers */
static const u16 iproc_pcie_reg_paxc[] = {
	[IPROC_PCIE_CLK_CTRL]     = 0x000,
	[IPROC_PCIE_CFG_IND_ADDR] = 0x1f0,
	[IPROC_PCIE_CFG_IND_DATA] = 0x1f4,
	[IPROC_PCIE_CFG_ADDR]     = 0x1f8,
	[IPROC_PCIE_CFG_DATA]     = 0x1fc,
	[IPROC_PCIE_INTX_EN]      = IPROC_PCIE_REG_INVALID,
	[IPROC_PCIE_OARR_LO]      = IPROC_PCIE_REG_INVALID,
	[IPROC_PCIE_OARR_HI]      = IPROC_PCIE_REG_INVALID,
	[IPROC_PCIE_OMAP_LO]      = IPROC_PCIE_REG_INVALID,
	[IPROC_PCIE_OMAP_HI]      = IPROC_PCIE_REG_INVALID,
	[IPROC_PCIE_LINK_STATUS]  = IPROC_PCIE_REG_INVALID,
};

static inline struct iproc_pcie *iproc_data(struct pci_bus *bus)
{
	struct iproc_pcie *pcie;
#ifdef CONFIG_ARM
	struct pci_sys_data *sys = bus->sysdata;

	pcie = sys->private_data;
#else
	pcie = bus->sysdata;
#endif
	return pcie;
}

static inline bool iproc_pcie_reg_is_invalid(u16 reg_offset)
{
	return !!(reg_offset == IPROC_PCIE_REG_INVALID);
}

static inline u16 iproc_pcie_reg_offset(struct iproc_pcie *pcie,
					enum iproc_pcie_reg reg)
{
	return pcie->reg_offsets[reg];
}

static inline u32 iproc_pcie_read_reg(struct iproc_pcie *pcie,
				      enum iproc_pcie_reg reg)
{
	u16 offset = iproc_pcie_reg_offset(pcie, reg);

	if (iproc_pcie_reg_is_invalid(offset))
		return 0;

	return readl(pcie->base + offset);
}

static inline void iproc_pcie_write_reg(struct iproc_pcie *pcie,
					enum iproc_pcie_reg reg, u32 val)
{
	u16 offset = iproc_pcie_reg_offset(pcie, reg);

	if (iproc_pcie_reg_is_invalid(offset))
		return;

	writel(val, pcie->base + offset);
}

static inline void iproc_pcie_ob_write(struct iproc_pcie *pcie,
				       enum iproc_pcie_reg reg,
				       unsigned window, u32 val)
{
	u16 offset = iproc_pcie_reg_offset(pcie, reg);

	if (iproc_pcie_reg_is_invalid(offset))
		return;

	writel(val, pcie->base + offset + (window * 8));
}

/**
 * Note access to the configuration registers are protected at the higher layer
 * by 'pci_lock' in drivers/pci/access.c
 */
static void __iomem *iproc_pcie_map_cfg_bus(struct pci_bus *bus,
					    unsigned int devfn,
					    int where)
{
	struct iproc_pcie *pcie = iproc_data(bus);
	unsigned slot = PCI_SLOT(devfn);
	unsigned fn = PCI_FUNC(devfn);
	unsigned busno = bus->number;
	u32 val;
	u16 offset;

	/* root complex access */
	if (busno == 0) {
		if (slot > 0 || fn > 0)
			return NULL;

		iproc_pcie_write_reg(pcie, IPROC_PCIE_CFG_IND_ADDR,
				     where & CFG_IND_ADDR_MASK);
		offset = iproc_pcie_reg_offset(pcie, IPROC_PCIE_CFG_IND_DATA);
		if (iproc_pcie_reg_is_invalid(offset))
			return NULL;
		else
			return (pcie->base + offset);
	}

	/*
	 * PAXC is connected to an internally emulated EP within the SoC.  It
	 * allows only one device.
	 */
	if (pcie->type == IPROC_PCIE_PAXC)
		if (slot > 0)
			return NULL;

	/* EP device access */
	val = (busno << CFG_ADDR_BUS_NUM_SHIFT) |
		(slot << CFG_ADDR_DEV_NUM_SHIFT) |
		(fn << CFG_ADDR_FUNC_NUM_SHIFT) |
		(where & CFG_ADDR_REG_NUM_MASK) |
		(1 & CFG_ADDR_CFG_TYPE_MASK);
	iproc_pcie_write_reg(pcie, IPROC_PCIE_CFG_ADDR, val);
	offset = iproc_pcie_reg_offset(pcie, IPROC_PCIE_CFG_DATA);
	if (iproc_pcie_reg_is_invalid(offset))
		return NULL;
	else
		return (pcie->base + offset);
}

static struct pci_ops iproc_pcie_ops = {
	.map_bus = iproc_pcie_map_cfg_bus,
	.read = pci_generic_config_read32,
	.write = pci_generic_config_write32,
};

static void iproc_pcie_reset(struct iproc_pcie *pcie)
{
	u32 val;

	if (pcie->type == IPROC_PCIE_PAXC) {
		val = iproc_pcie_read_reg(pcie, IPROC_PCIE_CLK_CTRL);
		val &= ~PAXC_RESET_MASK;
		iproc_pcie_write_reg(pcie, IPROC_PCIE_CLK_CTRL, val);
		udelay(100);
		val |= PAXC_RESET_MASK;
		iproc_pcie_write_reg(pcie, IPROC_PCIE_CLK_CTRL, val);
		udelay(100);
		return;
	}

	/*
	 * Select perst_b signal as reset source. Put the device into reset,
	 * and then bring it out of reset
	 */
	val = iproc_pcie_read_reg(pcie, IPROC_PCIE_CLK_CTRL);
	val &= ~EP_PERST_SOURCE_SELECT & ~EP_MODE_SURVIVE_PERST &
		~RC_PCIE_RST_OUTPUT;
	iproc_pcie_write_reg(pcie, IPROC_PCIE_CLK_CTRL, val);
	udelay(250);

	val |= RC_PCIE_RST_OUTPUT;
	iproc_pcie_write_reg(pcie, IPROC_PCIE_CLK_CTRL, val);
	msleep(100);
}

static int iproc_pcie_check_link(struct iproc_pcie *pcie, struct pci_bus *bus)
{
	u8 hdr_type;
	u32 link_ctrl, class, val;
	u16 pos, link_status;
	bool link_is_active = false;

	/*
	 * PAXC connects to emulated endpoint devices directly and does not
	 * have a Serdes.  Therefore skip the link detection logic here.
	 */
	if (pcie->type == IPROC_PCIE_PAXC)
		return 0;

	val = iproc_pcie_read_reg(pcie, IPROC_PCIE_LINK_STATUS);
	if (!(val & PCIE_PHYLINKUP) || !(val & PCIE_DL_ACTIVE)) {
		dev_err(pcie->dev, "PHY or data link is INACTIVE!\n");
		return -ENODEV;
	}

	/* make sure we are not in EP mode */
	pci_bus_read_config_byte(bus, 0, PCI_HEADER_TYPE, &hdr_type);
	if ((hdr_type & 0x7f) != PCI_HEADER_TYPE_BRIDGE) {
		dev_err(pcie->dev, "in EP mode, hdr=%#02x\n", hdr_type);
		return -EFAULT;
	}

	/* force class to PCI_CLASS_BRIDGE_PCI (0x0604) */
#define PCI_BRIDGE_CTRL_REG_OFFSET 0x43c
#define PCI_CLASS_BRIDGE_MASK      0xffff00
#define PCI_CLASS_BRIDGE_SHIFT     8
	pci_bus_read_config_dword(bus, 0, PCI_BRIDGE_CTRL_REG_OFFSET, &class);
	class &= ~PCI_CLASS_BRIDGE_MASK;
	class |= (PCI_CLASS_BRIDGE_PCI << PCI_CLASS_BRIDGE_SHIFT);
	pci_bus_write_config_dword(bus, 0, PCI_BRIDGE_CTRL_REG_OFFSET, class);

	/* check link status to see if link is active */
	pos = pci_bus_find_capability(bus, 0, PCI_CAP_ID_EXP);
	pci_bus_read_config_word(bus, 0, pos + PCI_EXP_LNKSTA, &link_status);
	if (link_status & PCI_EXP_LNKSTA_NLW)
		link_is_active = true;

	if (!link_is_active) {
		/* try GEN 1 link speed */
#define PCI_LINK_STATUS_CTRL_2_OFFSET 0x0dc
#define PCI_TARGET_LINK_SPEED_MASK    0xf
#define PCI_TARGET_LINK_SPEED_GEN2    0x2
#define PCI_TARGET_LINK_SPEED_GEN1    0x1
		pci_bus_read_config_dword(bus, 0,
					  PCI_LINK_STATUS_CTRL_2_OFFSET,
					  &link_ctrl);
		if ((link_ctrl & PCI_TARGET_LINK_SPEED_MASK) ==
		    PCI_TARGET_LINK_SPEED_GEN2) {
			link_ctrl &= ~PCI_TARGET_LINK_SPEED_MASK;
			link_ctrl |= PCI_TARGET_LINK_SPEED_GEN1;
			pci_bus_write_config_dword(bus, 0,
					   PCI_LINK_STATUS_CTRL_2_OFFSET,
					   link_ctrl);
			msleep(100);

			pos = pci_bus_find_capability(bus, 0, PCI_CAP_ID_EXP);
			pci_bus_read_config_word(bus, 0, pos + PCI_EXP_LNKSTA,
						 &link_status);
			if (link_status & PCI_EXP_LNKSTA_NLW)
				link_is_active = true;
		}
	}

	dev_info(pcie->dev, "link: %s\n", link_is_active ? "UP" : "DOWN");

	return link_is_active ? 0 : -ENODEV;
}

static void iproc_pcie_enable(struct iproc_pcie *pcie)
{
	iproc_pcie_write_reg(pcie, IPROC_PCIE_INTX_EN, SYS_RC_INTX_MASK);
}

/**
 * Some iProc SoCs require the SW to configure the outbound address mapping
 *
 * Outbound address translation:
 *
 * iproc_pcie_address = axi_address - axi_offset
 * OARR = iproc_pcie_address
 * OMAP = pci_addr
 *
 * axi_addr -> iproc_pcie_address -> OARR -> OMAP -> pci_address
 */
static int iproc_pcie_setup_ob(struct iproc_pcie *pcie, u64 axi_addr,
			       u64 pci_addr, resource_size_t size)
{
	struct iproc_pcie_ob *ob = &pcie->ob;
	unsigned i;
	u64 max_size = (u64)ob->window_size * MAX_NUM_OB_WINDOWS;
	u64 remainder;

	if (size > max_size) {
		dev_err(pcie->dev,
			"res size %pap exceeds max supported size 0x%llx\n",
			&size, max_size);
		return -EINVAL;
	}

	div64_u64_rem(size, ob->window_size, &remainder);
	if (remainder) {
		dev_err(pcie->dev,
			"res size %pap needs to be multiple of window size %pap\n",
			&size, &ob->window_size);
		return -EINVAL;
	}

	if (axi_addr < ob->axi_offset) {
		dev_err(pcie->dev,
			"axi address %pap less than offset %pap\n",
			&axi_addr, &ob->axi_offset);
		return -EINVAL;
	}

	/*
	 * Translate the AXI address to the internal address used by the iProc
	 * PCIe core before programming the OARR
	 */
	axi_addr -= ob->axi_offset;

	for (i = 0; i < MAX_NUM_OB_WINDOWS; i++) {
		iproc_pcie_ob_write(pcie, IPROC_PCIE_OARR_LO, i,
				    lower_32_bits(axi_addr) | OARR_VALID |
				    (ob->set_oarr_size ? 1 : 0));
		iproc_pcie_ob_write(pcie, IPROC_PCIE_OARR_HI, i,
				    upper_32_bits(axi_addr));
		iproc_pcie_ob_write(pcie, IPROC_PCIE_OMAP_LO, i,
				    lower_32_bits(pci_addr));
		iproc_pcie_ob_write(pcie, IPROC_PCIE_OMAP_HI, i,
				    upper_32_bits(pci_addr));

		size -= ob->window_size;
		if (size == 0)
			break;

		axi_addr += ob->window_size;
		pci_addr += ob->window_size;
	}

	return 0;
}

static int iproc_pcie_map_ranges(struct iproc_pcie *pcie,
				 struct list_head *resources)
{
	struct resource_entry *window;
	int ret;

	resource_list_for_each_entry(window, resources) {
		struct resource *res = window->res;
		u64 res_type = resource_type(res);

		switch (res_type) {
		case IORESOURCE_IO:
		case IORESOURCE_BUS:
			break;
		case IORESOURCE_MEM:
			ret = iproc_pcie_setup_ob(pcie, res->start,
						  res->start - window->offset,
						  resource_size(res));
			if (ret)
				return ret;
			break;
		default:
			dev_err(pcie->dev, "invalid resource %pR\n", res);
			return -EINVAL;
		}
	}

	return 0;
}

static int iproc_pcie_msi_enable(struct iproc_pcie *pcie)
{
	struct device_node *msi_node;

	msi_node = of_parse_phandle(pcie->dev->of_node, "msi-parent", 0);
	if (!msi_node)
		return -ENODEV;

	/*
	 * If another MSI controller is being used, the call below should fail
	 * but that is okay
	 */
	return iproc_msi_init(pcie, msi_node);
}

static void iproc_pcie_msi_disable(struct iproc_pcie *pcie)
{
	iproc_msi_exit(pcie);
}

int iproc_pcie_setup(struct iproc_pcie *pcie, struct list_head *res)
{
	int ret;
	void *sysdata;
	struct pci_bus *bus;

	if (!pcie || !pcie->dev || !pcie->base)
		return -EINVAL;

	ret = devm_request_pci_bus_resources(pcie->dev, res);
	if (ret)
		return ret;

	ret = phy_init(pcie->phy);
	if (ret) {
		dev_err(pcie->dev, "unable to initialize PCIe PHY\n");
		return ret;
	}

	ret = phy_power_on(pcie->phy);
	if (ret) {
		dev_err(pcie->dev, "unable to power on PCIe PHY\n");
		goto err_exit_phy;
	}

	switch (pcie->type) {
	case IPROC_PCIE_PAXB:
		pcie->reg_offsets = iproc_pcie_reg_paxb;
		break;
	case IPROC_PCIE_PAXC:
		pcie->reg_offsets = iproc_pcie_reg_paxc;
		break;
	default:
		dev_err(pcie->dev, "incompatible iProc PCIe interface\n");
		ret = -EINVAL;
		goto err_power_off_phy;
	}

	iproc_pcie_reset(pcie);

	if (pcie->need_ob_cfg) {
		ret = iproc_pcie_map_ranges(pcie, res);
		if (ret) {
			dev_err(pcie->dev, "map failed\n");
			goto err_power_off_phy;
		}
	}

#ifdef CONFIG_ARM
	pcie->sysdata.private_data = pcie;
	sysdata = &pcie->sysdata;
#else
	sysdata = pcie;
#endif

	bus = pci_create_root_bus(pcie->dev, 0, &iproc_pcie_ops, sysdata, res);
	if (!bus) {
		dev_err(pcie->dev, "unable to create PCI root bus\n");
		ret = -ENOMEM;
		goto err_power_off_phy;
	}
	pcie->root_bus = bus;

	ret = iproc_pcie_check_link(pcie, bus);
	if (ret) {
		dev_err(pcie->dev, "no PCIe EP device detected\n");
		goto err_rm_root_bus;
	}

	iproc_pcie_enable(pcie);

	if (IS_ENABLED(CONFIG_PCI_MSI))
		if (iproc_pcie_msi_enable(pcie))
			dev_info(pcie->dev, "not using iProc MSI\n");

	pci_scan_child_bus(bus);
	pci_assign_unassigned_bus_resources(bus);
	pci_fixup_irqs(pci_common_swizzle, pcie->map_irq);
	pci_bus_add_devices(bus);

	return 0;

err_rm_root_bus:
	pci_stop_root_bus(bus);
	pci_remove_root_bus(bus);

err_power_off_phy:
	phy_power_off(pcie->phy);
err_exit_phy:
	phy_exit(pcie->phy);
	return ret;
}
EXPORT_SYMBOL(iproc_pcie_setup);

int iproc_pcie_remove(struct iproc_pcie *pcie)
{
	pci_stop_root_bus(pcie->root_bus);
	pci_remove_root_bus(pcie->root_bus);

	iproc_pcie_msi_disable(pcie);

	phy_power_off(pcie->phy);
	phy_exit(pcie->phy);

	return 0;
}
EXPORT_SYMBOL(iproc_pcie_remove);

MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>");
MODULE_DESCRIPTION("Broadcom iPROC PCIe common driver");
MODULE_LICENSE("GPL v2");