1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCIe host controller driver for Freescale i.MX6 SoCs
4 *
5 * Copyright (C) 2013 Kosagi
6 *		https://www.kosagi.com
7 *
8 * Author: Sean Cross <xobs@kosagi.com>
9 */
10
11#include <linux/bitfield.h>
12#include <linux/clk.h>
13#include <linux/delay.h>
14#include <linux/gpio.h>
15#include <linux/kernel.h>
16#include <linux/mfd/syscon.h>
17#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
18#include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
19#include <linux/module.h>
20#include <linux/of_gpio.h>
21#include <linux/of_device.h>
22#include <linux/of_address.h>
23#include <linux/pci.h>
24#include <linux/platform_device.h>
25#include <linux/regmap.h>
26#include <linux/regulator/consumer.h>
27#include <linux/resource.h>
28#include <linux/signal.h>
29#include <linux/types.h>
30#include <linux/interrupt.h>
31#include <linux/reset.h>
32#include <linux/pm_domain.h>
33#include <linux/pm_runtime.h>
34
35#include "pcie-designware.h"
36
37#define IMX8MQ_GPR_PCIE_REF_USE_PAD		BIT(9)
38#define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN	BIT(10)
39#define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE	BIT(11)
40#define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE	GENMASK(11, 8)
41#define IMX8MQ_PCIE2_BASE_ADDR			0x33c00000
42
43#define to_imx6_pcie(x)	dev_get_drvdata((x)->dev)
44
45enum imx6_pcie_variants {
46	IMX6Q,
47	IMX6SX,
48	IMX6QP,
49	IMX7D,
50	IMX8MQ,
51};
52
53#define IMX6_PCIE_FLAG_IMX6_PHY			BIT(0)
54#define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE	BIT(1)
55#define IMX6_PCIE_FLAG_SUPPORTS_SUSPEND		BIT(2)
56
57struct imx6_pcie_drvdata {
58	enum imx6_pcie_variants variant;
59	u32 flags;
60	int dbi_length;
61};
62
63struct imx6_pcie {
64	struct dw_pcie		*pci;
65	int			reset_gpio;
66	bool			gpio_active_high;
67	struct clk		*pcie_bus;
68	struct clk		*pcie_phy;
69	struct clk		*pcie_inbound_axi;
70	struct clk		*pcie;
71	struct clk		*pcie_aux;
72	struct regmap		*iomuxc_gpr;
73	u32			controller_id;
74	struct reset_control	*pciephy_reset;
75	struct reset_control	*apps_reset;
76	struct reset_control	*turnoff_reset;
77	u32			tx_deemph_gen1;
78	u32			tx_deemph_gen2_3p5db;
79	u32			tx_deemph_gen2_6db;
80	u32			tx_swing_full;
81	u32			tx_swing_low;
82	struct regulator	*vpcie;
83	void __iomem		*phy_base;
84
85	/* power domain for pcie */
86	struct device		*pd_pcie;
87	/* power domain for pcie phy */
88	struct device		*pd_pcie_phy;
89	const struct imx6_pcie_drvdata *drvdata;
90};
91
92/* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
93#define PHY_PLL_LOCK_WAIT_USLEEP_MAX	200
94#define PHY_PLL_LOCK_WAIT_TIMEOUT	(2000 * PHY_PLL_LOCK_WAIT_USLEEP_MAX)
95
96/* PCIe Port Logic registers (memory-mapped) */
97#define PL_OFFSET 0x700
98
99#define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
100#define PCIE_PHY_CTRL_DATA(x)		FIELD_PREP(GENMASK(15, 0), (x))
101#define PCIE_PHY_CTRL_CAP_ADR		BIT(16)
102#define PCIE_PHY_CTRL_CAP_DAT		BIT(17)
103#define PCIE_PHY_CTRL_WR		BIT(18)
104#define PCIE_PHY_CTRL_RD		BIT(19)
105
106#define PCIE_PHY_STAT (PL_OFFSET + 0x110)
107#define PCIE_PHY_STAT_ACK		BIT(16)
108
109/* PHY registers (not memory-mapped) */
110#define PCIE_PHY_ATEOVRD			0x10
111#define  PCIE_PHY_ATEOVRD_EN			BIT(2)
112#define  PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT	0
113#define  PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK	0x1
114
115#define PCIE_PHY_MPLL_OVRD_IN_LO		0x11
116#define  PCIE_PHY_MPLL_MULTIPLIER_SHIFT		2
117#define  PCIE_PHY_MPLL_MULTIPLIER_MASK		0x7f
118#define  PCIE_PHY_MPLL_MULTIPLIER_OVRD		BIT(9)
119
120#define PCIE_PHY_RX_ASIC_OUT 0x100D
121#define PCIE_PHY_RX_ASIC_OUT_VALID	(1 << 0)
122
123/* iMX7 PCIe PHY registers */
124#define PCIE_PHY_CMN_REG4		0x14
125/* These are probably the bits that *aren't* DCC_FB_EN */
126#define PCIE_PHY_CMN_REG4_DCC_FB_EN	0x29
127
128#define PCIE_PHY_CMN_REG15	        0x54
129#define PCIE_PHY_CMN_REG15_DLY_4	BIT(2)
130#define PCIE_PHY_CMN_REG15_PLL_PD	BIT(5)
131#define PCIE_PHY_CMN_REG15_OVRD_PLL_PD	BIT(7)
132
133#define PCIE_PHY_CMN_REG24		0x90
134#define PCIE_PHY_CMN_REG24_RX_EQ	BIT(6)
135#define PCIE_PHY_CMN_REG24_RX_EQ_SEL	BIT(3)
136
137#define PCIE_PHY_CMN_REG26		0x98
138#define PCIE_PHY_CMN_REG26_ATT_MODE	0xBC
139
140#define PHY_RX_OVRD_IN_LO 0x1005
141#define PHY_RX_OVRD_IN_LO_RX_DATA_EN		BIT(5)
142#define PHY_RX_OVRD_IN_LO_RX_PLL_EN		BIT(3)
143
144static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, bool exp_val)
145{
146	struct dw_pcie *pci = imx6_pcie->pci;
147	bool val;
148	u32 max_iterations = 10;
149	u32 wait_counter = 0;
150
151	do {
152		val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT) &
153			PCIE_PHY_STAT_ACK;
154		wait_counter++;
155
156		if (val == exp_val)
157			return 0;
158
159		udelay(1);
160	} while (wait_counter < max_iterations);
161
162	return -ETIMEDOUT;
163}
164
165static int pcie_phy_wait_ack(struct imx6_pcie *imx6_pcie, int addr)
166{
167	struct dw_pcie *pci = imx6_pcie->pci;
168	u32 val;
169	int ret;
170
171	val = PCIE_PHY_CTRL_DATA(addr);
172	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
173
174	val |= PCIE_PHY_CTRL_CAP_ADR;
175	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
176
177	ret = pcie_phy_poll_ack(imx6_pcie, true);
178	if (ret)
179		return ret;
180
181	val = PCIE_PHY_CTRL_DATA(addr);
182	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
183
184	return pcie_phy_poll_ack(imx6_pcie, false);
185}
186
187/* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
188static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int addr, u16 *data)
189{
190	struct dw_pcie *pci = imx6_pcie->pci;
191	u32 phy_ctl;
192	int ret;
193
194	ret = pcie_phy_wait_ack(imx6_pcie, addr);
195	if (ret)
196		return ret;
197
198	/* assert Read signal */
199	phy_ctl = PCIE_PHY_CTRL_RD;
200	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, phy_ctl);
201
202	ret = pcie_phy_poll_ack(imx6_pcie, true);
203	if (ret)
204		return ret;
205
206	*data = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT);
207
208	/* deassert Read signal */
209	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x00);
210
211	return pcie_phy_poll_ack(imx6_pcie, false);
212}
213
214static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, u16 data)
215{
216	struct dw_pcie *pci = imx6_pcie->pci;
217	u32 var;
218	int ret;
219
220	/* write addr */
221	/* cap addr */
222	ret = pcie_phy_wait_ack(imx6_pcie, addr);
223	if (ret)
224		return ret;
225
226	var = PCIE_PHY_CTRL_DATA(data);
227	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
228
229	/* capture data */
230	var |= PCIE_PHY_CTRL_CAP_DAT;
231	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
232
233	ret = pcie_phy_poll_ack(imx6_pcie, true);
234	if (ret)
235		return ret;
236
237	/* deassert cap data */
238	var = PCIE_PHY_CTRL_DATA(data);
239	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
240
241	/* wait for ack de-assertion */
242	ret = pcie_phy_poll_ack(imx6_pcie, false);
243	if (ret)
244		return ret;
245
246	/* assert wr signal */
247	var = PCIE_PHY_CTRL_WR;
248	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
249
250	/* wait for ack */
251	ret = pcie_phy_poll_ack(imx6_pcie, true);
252	if (ret)
253		return ret;
254
255	/* deassert wr signal */
256	var = PCIE_PHY_CTRL_DATA(data);
257	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
258
259	/* wait for ack de-assertion */
260	ret = pcie_phy_poll_ack(imx6_pcie, false);
261	if (ret)
262		return ret;
263
264	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x0);
265
266	return 0;
267}
268
269static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
270{
271	u16 tmp;
272
273	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
274		return;
275
276	pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
277	tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
278		PHY_RX_OVRD_IN_LO_RX_PLL_EN);
279	pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
280
281	usleep_range(2000, 3000);
282
283	pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
284	tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
285		  PHY_RX_OVRD_IN_LO_RX_PLL_EN);
286	pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
287}
288
289#ifdef CONFIG_ARM
290/*  Added for PCI abort handling */
291static int imx6q_pcie_abort_handler(unsigned long addr,
292		unsigned int fsr, struct pt_regs *regs)
293{
294	unsigned long pc = instruction_pointer(regs);
295	unsigned long instr = *(unsigned long *)pc;
296	int reg = (instr >> 12) & 15;
297
298	/*
299	 * If the instruction being executed was a read,
300	 * make it look like it read all-ones.
301	 */
302	if ((instr & 0x0c100000) == 0x04100000) {
303		unsigned long val;
304
305		if (instr & 0x00400000)
306			val = 255;
307		else
308			val = -1;
309
310		regs->uregs[reg] = val;
311		regs->ARM_pc += 4;
312		return 0;
313	}
314
315	if ((instr & 0x0e100090) == 0x00100090) {
316		regs->uregs[reg] = -1;
317		regs->ARM_pc += 4;
318		return 0;
319	}
320
321	return 1;
322}
323#endif
324
325static int imx6_pcie_attach_pd(struct device *dev)
326{
327	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
328	struct device_link *link;
329
330	/* Do nothing when in a single power domain */
331	if (dev->pm_domain)
332		return 0;
333
334	imx6_pcie->pd_pcie = dev_pm_domain_attach_by_name(dev, "pcie");
335	if (IS_ERR(imx6_pcie->pd_pcie))
336		return PTR_ERR(imx6_pcie->pd_pcie);
337	/* Do nothing when power domain missing */
338	if (!imx6_pcie->pd_pcie)
339		return 0;
340	link = device_link_add(dev, imx6_pcie->pd_pcie,
341			DL_FLAG_STATELESS |
342			DL_FLAG_PM_RUNTIME |
343			DL_FLAG_RPM_ACTIVE);
344	if (!link) {
345		dev_err(dev, "Failed to add device_link to pcie pd.\n");
346		return -EINVAL;
347	}
348
349	imx6_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy");
350	if (IS_ERR(imx6_pcie->pd_pcie_phy))
351		return PTR_ERR(imx6_pcie->pd_pcie_phy);
352
353	link = device_link_add(dev, imx6_pcie->pd_pcie_phy,
354			DL_FLAG_STATELESS |
355			DL_FLAG_PM_RUNTIME |
356			DL_FLAG_RPM_ACTIVE);
357	if (!link) {
358		dev_err(dev, "Failed to add device_link to pcie_phy pd.\n");
359		return -EINVAL;
360	}
361
362	return 0;
363}
364
365static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
366{
367	struct device *dev = imx6_pcie->pci->dev;
368
369	switch (imx6_pcie->drvdata->variant) {
370	case IMX7D:
371	case IMX8MQ:
372		reset_control_assert(imx6_pcie->pciephy_reset);
373		reset_control_assert(imx6_pcie->apps_reset);
374		break;
375	case IMX6SX:
376		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
377				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
378				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
379		/* Force PCIe PHY reset */
380		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
381				   IMX6SX_GPR5_PCIE_BTNRST_RESET,
382				   IMX6SX_GPR5_PCIE_BTNRST_RESET);
383		break;
384	case IMX6QP:
385		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
386				   IMX6Q_GPR1_PCIE_SW_RST,
387				   IMX6Q_GPR1_PCIE_SW_RST);
388		break;
389	case IMX6Q:
390		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
391				   IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
392		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
393				   IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
394		break;
395	}
396
397	if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
398		int ret = regulator_disable(imx6_pcie->vpcie);
399
400		if (ret)
401			dev_err(dev, "failed to disable vpcie regulator: %d\n",
402				ret);
403	}
404
405	/* Some boards don't have PCIe reset GPIO. */
406	if (gpio_is_valid(imx6_pcie->reset_gpio))
407		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
408					imx6_pcie->gpio_active_high);
409}
410
411static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
412{
413	WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ);
414	return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14;
415}
416
417static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
418{
419	struct dw_pcie *pci = imx6_pcie->pci;
420	struct device *dev = pci->dev;
421	unsigned int offset;
422	int ret = 0;
423
424	switch (imx6_pcie->drvdata->variant) {
425	case IMX6SX:
426		ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
427		if (ret) {
428			dev_err(dev, "unable to enable pcie_axi clock\n");
429			break;
430		}
431
432		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
433				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
434		break;
435	case IMX6QP:
436	case IMX6Q:
437		/* power up core phy and enable ref clock */
438		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
439				   IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
440		/*
441		 * the async reset input need ref clock to sync internally,
442		 * when the ref clock comes after reset, internal synced
443		 * reset time is too short, cannot meet the requirement.
444		 * add one ~10us delay here.
445		 */
446		usleep_range(10, 100);
447		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
448				   IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
449		break;
450	case IMX7D:
451		break;
452	case IMX8MQ:
453		ret = clk_prepare_enable(imx6_pcie->pcie_aux);
454		if (ret) {
455			dev_err(dev, "unable to enable pcie_aux clock\n");
456			break;
457		}
458
459		offset = imx6_pcie_grp_offset(imx6_pcie);
460		/*
461		 * Set the over ride low and enabled
462		 * make sure that REF_CLK is turned on.
463		 */
464		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
465				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE,
466				   0);
467		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
468				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
469				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
470		break;
471	}
472
473	return ret;
474}
475
476static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)
477{
478	u32 val;
479	struct device *dev = imx6_pcie->pci->dev;
480
481	if (regmap_read_poll_timeout(imx6_pcie->iomuxc_gpr,
482				     IOMUXC_GPR22, val,
483				     val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED,
484				     PHY_PLL_LOCK_WAIT_USLEEP_MAX,
485				     PHY_PLL_LOCK_WAIT_TIMEOUT))
486		dev_err(dev, "PCIe PLL lock timeout\n");
487}
488
489static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
490{
491	struct dw_pcie *pci = imx6_pcie->pci;
492	struct device *dev = pci->dev;
493	int ret;
494
495	if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) {
496		ret = regulator_enable(imx6_pcie->vpcie);
497		if (ret) {
498			dev_err(dev, "failed to enable vpcie regulator: %d\n",
499				ret);
500			return;
501		}
502	}
503
504	ret = clk_prepare_enable(imx6_pcie->pcie_phy);
505	if (ret) {
506		dev_err(dev, "unable to enable pcie_phy clock\n");
507		goto err_pcie_phy;
508	}
509
510	ret = clk_prepare_enable(imx6_pcie->pcie_bus);
511	if (ret) {
512		dev_err(dev, "unable to enable pcie_bus clock\n");
513		goto err_pcie_bus;
514	}
515
516	ret = clk_prepare_enable(imx6_pcie->pcie);
517	if (ret) {
518		dev_err(dev, "unable to enable pcie clock\n");
519		goto err_pcie;
520	}
521
522	ret = imx6_pcie_enable_ref_clk(imx6_pcie);
523	if (ret) {
524		dev_err(dev, "unable to enable pcie ref clock\n");
525		goto err_ref_clk;
526	}
527
528	/* allow the clocks to stabilize */
529	usleep_range(200, 500);
530
531	switch (imx6_pcie->drvdata->variant) {
532	case IMX8MQ:
533		reset_control_deassert(imx6_pcie->pciephy_reset);
534		break;
535	case IMX7D:
536		reset_control_deassert(imx6_pcie->pciephy_reset);
537
538		/* Workaround for ERR010728, failure of PCI-e PLL VCO to
539		 * oscillate, especially when cold.  This turns off "Duty-cycle
540		 * Corrector" and other mysterious undocumented things.
541		 */
542		if (likely(imx6_pcie->phy_base)) {
543			/* De-assert DCC_FB_EN */
544			writel(PCIE_PHY_CMN_REG4_DCC_FB_EN,
545			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG4);
546			/* Assert RX_EQS and RX_EQS_SEL */
547			writel(PCIE_PHY_CMN_REG24_RX_EQ_SEL
548				| PCIE_PHY_CMN_REG24_RX_EQ,
549			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG24);
550			/* Assert ATT_MODE */
551			writel(PCIE_PHY_CMN_REG26_ATT_MODE,
552			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG26);
553		} else {
554			dev_warn(dev, "Unable to apply ERR010728 workaround. DT missing fsl,imx7d-pcie-phy phandle ?\n");
555		}
556
557		imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
558		break;
559	case IMX6SX:
560		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
561				   IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
562		break;
563	case IMX6QP:
564		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
565				   IMX6Q_GPR1_PCIE_SW_RST, 0);
566
567		usleep_range(200, 500);
568		break;
569	case IMX6Q:		/* Nothing to do */
570		break;
571	}
572
573	/* Some boards don't have PCIe reset GPIO. */
574	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
575		msleep(100);
576		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
577					!imx6_pcie->gpio_active_high);
578		/* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
579		msleep(100);
580	}
581
582	return;
583
584err_ref_clk:
585	clk_disable_unprepare(imx6_pcie->pcie);
586err_pcie:
587	clk_disable_unprepare(imx6_pcie->pcie_bus);
588err_pcie_bus:
589	clk_disable_unprepare(imx6_pcie->pcie_phy);
590err_pcie_phy:
591	if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
592		ret = regulator_disable(imx6_pcie->vpcie);
593		if (ret)
594			dev_err(dev, "failed to disable vpcie regulator: %d\n",
595				ret);
596	}
597}
598
599static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie)
600{
601	unsigned int mask, val;
602
603	if (imx6_pcie->drvdata->variant == IMX8MQ &&
604	    imx6_pcie->controller_id == 1) {
605		mask   = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE;
606		val    = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
607				    PCI_EXP_TYPE_ROOT_PORT);
608	} else {
609		mask = IMX6Q_GPR12_DEVICE_TYPE;
610		val  = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE,
611				  PCI_EXP_TYPE_ROOT_PORT);
612	}
613
614	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val);
615}
616
617static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
618{
619	switch (imx6_pcie->drvdata->variant) {
620	case IMX8MQ:
621		/*
622		 * TODO: Currently this code assumes external
623		 * oscillator is being used
624		 */
625		regmap_update_bits(imx6_pcie->iomuxc_gpr,
626				   imx6_pcie_grp_offset(imx6_pcie),
627				   IMX8MQ_GPR_PCIE_REF_USE_PAD,
628				   IMX8MQ_GPR_PCIE_REF_USE_PAD);
629		break;
630	case IMX7D:
631		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
632				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
633		break;
634	case IMX6SX:
635		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
636				   IMX6SX_GPR12_PCIE_RX_EQ_MASK,
637				   IMX6SX_GPR12_PCIE_RX_EQ_2);
638		fallthrough;
639	default:
640		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
641				   IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
642
643		/* configure constant input signal to the pcie ctrl and phy */
644		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
645				   IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
646
647		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
648				   IMX6Q_GPR8_TX_DEEMPH_GEN1,
649				   imx6_pcie->tx_deemph_gen1 << 0);
650		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
651				   IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
652				   imx6_pcie->tx_deemph_gen2_3p5db << 6);
653		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
654				   IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
655				   imx6_pcie->tx_deemph_gen2_6db << 12);
656		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
657				   IMX6Q_GPR8_TX_SWING_FULL,
658				   imx6_pcie->tx_swing_full << 18);
659		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
660				   IMX6Q_GPR8_TX_SWING_LOW,
661				   imx6_pcie->tx_swing_low << 25);
662		break;
663	}
664
665	imx6_pcie_configure_type(imx6_pcie);
666}
667
668static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
669{
670	unsigned long phy_rate = clk_get_rate(imx6_pcie->pcie_phy);
671	int mult, div;
672	u16 val;
673
674	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
675		return 0;
676
677	switch (phy_rate) {
678	case 125000000:
679		/*
680		 * The default settings of the MPLL are for a 125MHz input
681		 * clock, so no need to reconfigure anything in that case.
682		 */
683		return 0;
684	case 100000000:
685		mult = 25;
686		div = 0;
687		break;
688	case 200000000:
689		mult = 25;
690		div = 1;
691		break;
692	default:
693		dev_err(imx6_pcie->pci->dev,
694			"Unsupported PHY reference clock rate %lu\n", phy_rate);
695		return -EINVAL;
696	}
697
698	pcie_phy_read(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, &val);
699	val &= ~(PCIE_PHY_MPLL_MULTIPLIER_MASK <<
700		 PCIE_PHY_MPLL_MULTIPLIER_SHIFT);
701	val |= mult << PCIE_PHY_MPLL_MULTIPLIER_SHIFT;
702	val |= PCIE_PHY_MPLL_MULTIPLIER_OVRD;
703	pcie_phy_write(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, val);
704
705	pcie_phy_read(imx6_pcie, PCIE_PHY_ATEOVRD, &val);
706	val &= ~(PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK <<
707		 PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT);
708	val |= div << PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT;
709	val |= PCIE_PHY_ATEOVRD_EN;
710	pcie_phy_write(imx6_pcie, PCIE_PHY_ATEOVRD, val);
711
712	return 0;
713}
714
715static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie)
716{
717	struct dw_pcie *pci = imx6_pcie->pci;
718	struct device *dev = pci->dev;
719	u32 tmp;
720	unsigned int retries;
721
722	for (retries = 0; retries < 200; retries++) {
723		tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
724		/* Test if the speed change finished. */
725		if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
726			return 0;
727		usleep_range(100, 1000);
728	}
729
730	dev_err(dev, "Speed change timeout\n");
731	return -ETIMEDOUT;
732}
733
734static void imx6_pcie_ltssm_enable(struct device *dev)
735{
736	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
737
738	switch (imx6_pcie->drvdata->variant) {
739	case IMX6Q:
740	case IMX6SX:
741	case IMX6QP:
742		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
743				   IMX6Q_GPR12_PCIE_CTL_2,
744				   IMX6Q_GPR12_PCIE_CTL_2);
745		break;
746	case IMX7D:
747	case IMX8MQ:
748		reset_control_deassert(imx6_pcie->apps_reset);
749		break;
750	}
751}
752
753static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
754{
755	struct dw_pcie *pci = imx6_pcie->pci;
756	struct device *dev = pci->dev;
757	u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
758	u32 tmp;
759	int ret;
760
761	/*
762	 * Force Gen1 operation when starting the link.  In case the link is
763	 * started in Gen2 mode, there is a possibility the devices on the
764	 * bus will not be detected at all.  This happens with PCIe switches.
765	 */
766	tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
767	tmp &= ~PCI_EXP_LNKCAP_SLS;
768	tmp |= PCI_EXP_LNKCAP_SLS_2_5GB;
769	dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
770
771	/* Start LTSSM. */
772	imx6_pcie_ltssm_enable(dev);
773
774	ret = dw_pcie_wait_for_link(pci);
775	if (ret)
776		goto err_reset_phy;
777
778	if (pci->link_gen == 2) {
779		/* Allow Gen2 mode after the link is up. */
780		tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
781		tmp &= ~PCI_EXP_LNKCAP_SLS;
782		tmp |= PCI_EXP_LNKCAP_SLS_5_0GB;
783		dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
784
785		/*
786		 * Start Directed Speed Change so the best possible
787		 * speed both link partners support can be negotiated.
788		 */
789		tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
790		tmp |= PORT_LOGIC_SPEED_CHANGE;
791		dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
792
793		if (imx6_pcie->drvdata->flags &
794		    IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE) {
795			/*
796			 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
797			 * from i.MX6 family when no link speed transition
798			 * occurs and we go Gen1 -> yep, Gen1. The difference
799			 * is that, in such case, it will not be cleared by HW
800			 * which will cause the following code to report false
801			 * failure.
802			 */
803
804			ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
805			if (ret) {
806				dev_err(dev, "Failed to bring link up!\n");
807				goto err_reset_phy;
808			}
809		}
810
811		/* Make sure link training is finished as well! */
812		ret = dw_pcie_wait_for_link(pci);
813		if (ret) {
814			dev_err(dev, "Failed to bring link up!\n");
815			goto err_reset_phy;
816		}
817	} else {
818		dev_info(dev, "Link: Gen2 disabled\n");
819	}
820
821	tmp = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA);
822	dev_info(dev, "Link up, Gen%i\n", tmp & PCI_EXP_LNKSTA_CLS);
823	return 0;
824
825err_reset_phy:
826	dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
827		dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0),
828		dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1));
829	imx6_pcie_reset_phy(imx6_pcie);
830	return ret;
831}
832
833static int imx6_pcie_host_init(struct pcie_port *pp)
834{
835	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
836	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
837
838	imx6_pcie_assert_core_reset(imx6_pcie);
839	imx6_pcie_init_phy(imx6_pcie);
840	imx6_pcie_deassert_core_reset(imx6_pcie);
841	imx6_setup_phy_mpll(imx6_pcie);
842	dw_pcie_setup_rc(pp);
843	imx6_pcie_establish_link(imx6_pcie);
844	dw_pcie_msi_init(pp);
845
846	return 0;
847}
848
849static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
850	.host_init = imx6_pcie_host_init,
851};
852
853static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie,
854			      struct platform_device *pdev)
855{
856	struct dw_pcie *pci = imx6_pcie->pci;
857	struct pcie_port *pp = &pci->pp;
858	struct device *dev = &pdev->dev;
859	int ret;
860
861	if (IS_ENABLED(CONFIG_PCI_MSI)) {
862		pp->msi_irq = platform_get_irq_byname(pdev, "msi");
863		if (pp->msi_irq < 0)
864			return pp->msi_irq;
865	}
866
867	pp->ops = &imx6_pcie_host_ops;
868
869	ret = dw_pcie_host_init(pp);
870	if (ret) {
871		dev_err(dev, "failed to initialize host\n");
872		return ret;
873	}
874
875	return 0;
876}
877
878static const struct dw_pcie_ops dw_pcie_ops = {
879	/* No special ops needed, but pcie-designware still expects this struct */
880};
881
882#ifdef CONFIG_PM_SLEEP
883static void imx6_pcie_ltssm_disable(struct device *dev)
884{
885	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
886
887	switch (imx6_pcie->drvdata->variant) {
888	case IMX6SX:
889	case IMX6QP:
890		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
891				   IMX6Q_GPR12_PCIE_CTL_2, 0);
892		break;
893	case IMX7D:
894		reset_control_assert(imx6_pcie->apps_reset);
895		break;
896	default:
897		dev_err(dev, "ltssm_disable not supported\n");
898	}
899}
900
901static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
902{
903	struct device *dev = imx6_pcie->pci->dev;
904
905	/* Some variants have a turnoff reset in DT */
906	if (imx6_pcie->turnoff_reset) {
907		reset_control_assert(imx6_pcie->turnoff_reset);
908		reset_control_deassert(imx6_pcie->turnoff_reset);
909		goto pm_turnoff_sleep;
910	}
911
912	/* Others poke directly at IOMUXC registers */
913	switch (imx6_pcie->drvdata->variant) {
914	case IMX6SX:
915		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
916				IMX6SX_GPR12_PCIE_PM_TURN_OFF,
917				IMX6SX_GPR12_PCIE_PM_TURN_OFF);
918		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
919				IMX6SX_GPR12_PCIE_PM_TURN_OFF, 0);
920		break;
921	default:
922		dev_err(dev, "PME_Turn_Off not implemented\n");
923		return;
924	}
925
926	/*
927	 * Components with an upstream port must respond to
928	 * PME_Turn_Off with PME_TO_Ack but we can't check.
929	 *
930	 * The standard recommends a 1-10ms timeout after which to
931	 * proceed anyway as if acks were received.
932	 */
933pm_turnoff_sleep:
934	usleep_range(1000, 10000);
935}
936
937static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
938{
939	clk_disable_unprepare(imx6_pcie->pcie);
940	clk_disable_unprepare(imx6_pcie->pcie_phy);
941	clk_disable_unprepare(imx6_pcie->pcie_bus);
942
943	switch (imx6_pcie->drvdata->variant) {
944	case IMX6SX:
945		clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
946		break;
947	case IMX7D:
948		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
949				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
950				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
951		break;
952	case IMX8MQ:
953		clk_disable_unprepare(imx6_pcie->pcie_aux);
954		break;
955	default:
956		break;
957	}
958}
959
960static int imx6_pcie_suspend_noirq(struct device *dev)
961{
962	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
963
964	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
965		return 0;
966
967	imx6_pcie_pm_turnoff(imx6_pcie);
968	imx6_pcie_clk_disable(imx6_pcie);
969	imx6_pcie_ltssm_disable(dev);
970
971	return 0;
972}
973
974static int imx6_pcie_resume_noirq(struct device *dev)
975{
976	int ret;
977	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
978	struct pcie_port *pp = &imx6_pcie->pci->pp;
979
980	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
981		return 0;
982
983	imx6_pcie_assert_core_reset(imx6_pcie);
984	imx6_pcie_init_phy(imx6_pcie);
985	imx6_pcie_deassert_core_reset(imx6_pcie);
986	dw_pcie_setup_rc(pp);
987
988	ret = imx6_pcie_establish_link(imx6_pcie);
989	if (ret < 0)
990		dev_info(dev, "pcie link is down after resume.\n");
991
992	return 0;
993}
994#endif
995
996static const struct dev_pm_ops imx6_pcie_pm_ops = {
997	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq,
998				      imx6_pcie_resume_noirq)
999};
1000
1001static int imx6_pcie_probe(struct platform_device *pdev)
1002{
1003	struct device *dev = &pdev->dev;
1004	struct dw_pcie *pci;
1005	struct imx6_pcie *imx6_pcie;
1006	struct device_node *np;
1007	struct resource *dbi_base;
1008	struct device_node *node = dev->of_node;
1009	int ret;
1010	u16 val;
1011
1012	imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
1013	if (!imx6_pcie)
1014		return -ENOMEM;
1015
1016	pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
1017	if (!pci)
1018		return -ENOMEM;
1019
1020	pci->dev = dev;
1021	pci->ops = &dw_pcie_ops;
1022
1023	imx6_pcie->pci = pci;
1024	imx6_pcie->drvdata = of_device_get_match_data(dev);
1025
1026	/* Find the PHY if one is defined, only imx7d uses it */
1027	np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0);
1028	if (np) {
1029		struct resource res;
1030
1031		ret = of_address_to_resource(np, 0, &res);
1032		if (ret) {
1033			dev_err(dev, "Unable to map PCIe PHY\n");
1034			return ret;
1035		}
1036		imx6_pcie->phy_base = devm_ioremap_resource(dev, &res);
1037		if (IS_ERR(imx6_pcie->phy_base)) {
1038			dev_err(dev, "Unable to map PCIe PHY\n");
1039			return PTR_ERR(imx6_pcie->phy_base);
1040		}
1041	}
1042
1043	dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1044	pci->dbi_base = devm_ioremap_resource(dev, dbi_base);
1045	if (IS_ERR(pci->dbi_base))
1046		return PTR_ERR(pci->dbi_base);
1047
1048	/* Fetch GPIOs */
1049	imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
1050	imx6_pcie->gpio_active_high = of_property_read_bool(node,
1051						"reset-gpio-active-high");
1052	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
1053		ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
1054				imx6_pcie->gpio_active_high ?
1055					GPIOF_OUT_INIT_HIGH :
1056					GPIOF_OUT_INIT_LOW,
1057				"PCIe reset");
1058		if (ret) {
1059			dev_err(dev, "unable to get reset gpio\n");
1060			return ret;
1061		}
1062	} else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) {
1063		return imx6_pcie->reset_gpio;
1064	}
1065
1066	/* Fetch clocks */
1067	imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy");
1068	if (IS_ERR(imx6_pcie->pcie_phy))
1069		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_phy),
1070				     "pcie_phy clock source missing or invalid\n");
1071
1072	imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus");
1073	if (IS_ERR(imx6_pcie->pcie_bus))
1074		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_bus),
1075				     "pcie_bus clock source missing or invalid\n");
1076
1077	imx6_pcie->pcie = devm_clk_get(dev, "pcie");
1078	if (IS_ERR(imx6_pcie->pcie))
1079		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie),
1080				     "pcie clock source missing or invalid\n");
1081
1082	switch (imx6_pcie->drvdata->variant) {
1083	case IMX6SX:
1084		imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
1085							   "pcie_inbound_axi");
1086		if (IS_ERR(imx6_pcie->pcie_inbound_axi))
1087			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_inbound_axi),
1088					     "pcie_inbound_axi clock missing or invalid\n");
1089		break;
1090	case IMX8MQ:
1091		imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
1092		if (IS_ERR(imx6_pcie->pcie_aux))
1093			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
1094					     "pcie_aux clock source missing or invalid\n");
1095		fallthrough;
1096	case IMX7D:
1097		if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
1098			imx6_pcie->controller_id = 1;
1099
1100		imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
1101									    "pciephy");
1102		if (IS_ERR(imx6_pcie->pciephy_reset)) {
1103			dev_err(dev, "Failed to get PCIEPHY reset control\n");
1104			return PTR_ERR(imx6_pcie->pciephy_reset);
1105		}
1106
1107		imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
1108									 "apps");
1109		if (IS_ERR(imx6_pcie->apps_reset)) {
1110			dev_err(dev, "Failed to get PCIE APPS reset control\n");
1111			return PTR_ERR(imx6_pcie->apps_reset);
1112		}
1113		break;
1114	default:
1115		break;
1116	}
1117
1118	/* Grab turnoff reset */
1119	imx6_pcie->turnoff_reset = devm_reset_control_get_optional_exclusive(dev, "turnoff");
1120	if (IS_ERR(imx6_pcie->turnoff_reset)) {
1121		dev_err(dev, "Failed to get TURNOFF reset control\n");
1122		return PTR_ERR(imx6_pcie->turnoff_reset);
1123	}
1124
1125	/* Grab GPR config register range */
1126	imx6_pcie->iomuxc_gpr =
1127		 syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
1128	if (IS_ERR(imx6_pcie->iomuxc_gpr)) {
1129		dev_err(dev, "unable to find iomuxc registers\n");
1130		return PTR_ERR(imx6_pcie->iomuxc_gpr);
1131	}
1132
1133	/* Grab PCIe PHY Tx Settings */
1134	if (of_property_read_u32(node, "fsl,tx-deemph-gen1",
1135				 &imx6_pcie->tx_deemph_gen1))
1136		imx6_pcie->tx_deemph_gen1 = 0;
1137
1138	if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db",
1139				 &imx6_pcie->tx_deemph_gen2_3p5db))
1140		imx6_pcie->tx_deemph_gen2_3p5db = 0;
1141
1142	if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db",
1143				 &imx6_pcie->tx_deemph_gen2_6db))
1144		imx6_pcie->tx_deemph_gen2_6db = 20;
1145
1146	if (of_property_read_u32(node, "fsl,tx-swing-full",
1147				 &imx6_pcie->tx_swing_full))
1148		imx6_pcie->tx_swing_full = 127;
1149
1150	if (of_property_read_u32(node, "fsl,tx-swing-low",
1151				 &imx6_pcie->tx_swing_low))
1152		imx6_pcie->tx_swing_low = 127;
1153
1154	/* Limit link speed */
1155	pci->link_gen = 1;
1156	ret = of_property_read_u32(node, "fsl,max-link-speed", &pci->link_gen);
1157
1158	imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie");
1159	if (IS_ERR(imx6_pcie->vpcie)) {
1160		if (PTR_ERR(imx6_pcie->vpcie) != -ENODEV)
1161			return PTR_ERR(imx6_pcie->vpcie);
1162		imx6_pcie->vpcie = NULL;
1163	}
1164
1165	platform_set_drvdata(pdev, imx6_pcie);
1166
1167	ret = imx6_pcie_attach_pd(dev);
1168	if (ret)
1169		return ret;
1170
1171	ret = imx6_add_pcie_port(imx6_pcie, pdev);
1172	if (ret < 0)
1173		return ret;
1174
1175	if (pci_msi_enabled()) {
1176		u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
1177		val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
1178		val |= PCI_MSI_FLAGS_ENABLE;
1179		dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
1180	}
1181
1182	return 0;
1183}
1184
1185static void imx6_pcie_shutdown(struct platform_device *pdev)
1186{
1187	struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
1188
1189	/* bring down link, so bootloader gets clean state in case of reboot */
1190	imx6_pcie_assert_core_reset(imx6_pcie);
1191}
1192
1193static const struct imx6_pcie_drvdata drvdata[] = {
1194	[IMX6Q] = {
1195		.variant = IMX6Q,
1196		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1197			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1198		.dbi_length = 0x200,
1199	},
1200	[IMX6SX] = {
1201		.variant = IMX6SX,
1202		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1203			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
1204			 IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1205	},
1206	[IMX6QP] = {
1207		.variant = IMX6QP,
1208		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1209			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1210	},
1211	[IMX7D] = {
1212		.variant = IMX7D,
1213		.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1214	},
1215	[IMX8MQ] = {
1216		.variant = IMX8MQ,
1217	},
1218};
1219
1220static const struct of_device_id imx6_pcie_of_match[] = {
1221	{ .compatible = "fsl,imx6q-pcie",  .data = &drvdata[IMX6Q],  },
1222	{ .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], },
1223	{ .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], },
1224	{ .compatible = "fsl,imx7d-pcie",  .data = &drvdata[IMX7D],  },
1225	{ .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], } ,
1226	{},
1227};
1228
1229static struct platform_driver imx6_pcie_driver = {
1230	.driver = {
1231		.name	= "imx6q-pcie",
1232		.of_match_table = imx6_pcie_of_match,
1233		.suppress_bind_attrs = true,
1234		.pm = &imx6_pcie_pm_ops,
1235		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1236	},
1237	.probe    = imx6_pcie_probe,
1238	.shutdown = imx6_pcie_shutdown,
1239};
1240
1241static void imx6_pcie_quirk(struct pci_dev *dev)
1242{
1243	struct pci_bus *bus = dev->bus;
1244	struct pcie_port *pp = bus->sysdata;
1245
1246	/* Bus parent is the PCI bridge, its parent is this platform driver */
1247	if (!bus->dev.parent || !bus->dev.parent->parent)
1248		return;
1249
1250	/* Make sure we only quirk devices associated with this driver */
1251	if (bus->dev.parent->parent->driver != &imx6_pcie_driver.driver)
1252		return;
1253
1254	if (pci_is_root_bus(bus)) {
1255		struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1256		struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
1257
1258		/*
1259		 * Limit config length to avoid the kernel reading beyond
1260		 * the register set and causing an abort on i.MX 6Quad
1261		 */
1262		if (imx6_pcie->drvdata->dbi_length) {
1263			dev->cfg_size = imx6_pcie->drvdata->dbi_length;
1264			dev_info(&dev->dev, "Limiting cfg_size to %d\n",
1265					dev->cfg_size);
1266		}
1267	}
1268}
1269DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_SYNOPSYS, 0xabcd,
1270			PCI_CLASS_BRIDGE_PCI, 8, imx6_pcie_quirk);
1271
1272static int __init imx6_pcie_init(void)
1273{
1274#ifdef CONFIG_ARM
1275	struct device_node *np;
1276
1277	np = of_find_matching_node(NULL, imx6_pcie_of_match);
1278	if (!np)
1279		return -ENODEV;
1280	of_node_put(np);
1281
1282	/*
1283	 * Since probe() can be deferred we need to make sure that
1284	 * hook_fault_code is not called after __init memory is freed
1285	 * by kernel and since imx6q_pcie_abort_handler() is a no-op,
1286	 * we can install the handler here without risking it
1287	 * accessing some uninitialized driver state.
1288	 */
1289	hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0,
1290			"external abort on non-linefetch");
1291#endif
1292
1293	return platform_driver_register(&imx6_pcie_driver);
1294}
1295device_initcall(imx6_pcie_init);
1296