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.h>
21#include <linux/of_gpio.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/phy/phy.h>
33#include <linux/pm_domain.h>
34#include <linux/pm_runtime.h>
35
36#include "pcie-designware.h"
37
38#define IMX8MQ_GPR_PCIE_REF_USE_PAD		BIT(9)
39#define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN	BIT(10)
40#define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE	BIT(11)
41#define IMX8MQ_GPR_PCIE_VREG_BYPASS		BIT(12)
42#define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE	GENMASK(11, 8)
43#define IMX8MQ_PCIE2_BASE_ADDR			0x33c00000
44
45#define to_imx6_pcie(x)	dev_get_drvdata((x)->dev)
46
47enum imx6_pcie_variants {
48	IMX6Q,
49	IMX6SX,
50	IMX6QP,
51	IMX7D,
52	IMX8MQ,
53	IMX8MM,
54	IMX8MP,
55	IMX8MQ_EP,
56	IMX8MM_EP,
57	IMX8MP_EP,
58};
59
60#define IMX6_PCIE_FLAG_IMX6_PHY			BIT(0)
61#define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE	BIT(1)
62#define IMX6_PCIE_FLAG_SUPPORTS_SUSPEND		BIT(2)
63
64struct imx6_pcie_drvdata {
65	enum imx6_pcie_variants variant;
66	enum dw_pcie_device_mode mode;
67	u32 flags;
68	int dbi_length;
69	const char *gpr;
70};
71
72struct imx6_pcie {
73	struct dw_pcie		*pci;
74	int			reset_gpio;
75	bool			gpio_active_high;
76	bool			link_is_up;
77	struct clk		*pcie_bus;
78	struct clk		*pcie_phy;
79	struct clk		*pcie_inbound_axi;
80	struct clk		*pcie;
81	struct clk		*pcie_aux;
82	struct regmap		*iomuxc_gpr;
83	u16			msi_ctrl;
84	u32			controller_id;
85	struct reset_control	*pciephy_reset;
86	struct reset_control	*apps_reset;
87	struct reset_control	*turnoff_reset;
88	u32			tx_deemph_gen1;
89	u32			tx_deemph_gen2_3p5db;
90	u32			tx_deemph_gen2_6db;
91	u32			tx_swing_full;
92	u32			tx_swing_low;
93	struct regulator	*vpcie;
94	struct regulator	*vph;
95	void __iomem		*phy_base;
96
97	/* power domain for pcie */
98	struct device		*pd_pcie;
99	/* power domain for pcie phy */
100	struct device		*pd_pcie_phy;
101	struct phy		*phy;
102	const struct imx6_pcie_drvdata *drvdata;
103};
104
105/* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
106#define PHY_PLL_LOCK_WAIT_USLEEP_MAX	200
107#define PHY_PLL_LOCK_WAIT_TIMEOUT	(2000 * PHY_PLL_LOCK_WAIT_USLEEP_MAX)
108
109/* PCIe Port Logic registers (memory-mapped) */
110#define PL_OFFSET 0x700
111
112#define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
113#define PCIE_PHY_CTRL_DATA(x)		FIELD_PREP(GENMASK(15, 0), (x))
114#define PCIE_PHY_CTRL_CAP_ADR		BIT(16)
115#define PCIE_PHY_CTRL_CAP_DAT		BIT(17)
116#define PCIE_PHY_CTRL_WR		BIT(18)
117#define PCIE_PHY_CTRL_RD		BIT(19)
118
119#define PCIE_PHY_STAT (PL_OFFSET + 0x110)
120#define PCIE_PHY_STAT_ACK		BIT(16)
121
122/* PHY registers (not memory-mapped) */
123#define PCIE_PHY_ATEOVRD			0x10
124#define  PCIE_PHY_ATEOVRD_EN			BIT(2)
125#define  PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT	0
126#define  PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK	0x1
127
128#define PCIE_PHY_MPLL_OVRD_IN_LO		0x11
129#define  PCIE_PHY_MPLL_MULTIPLIER_SHIFT		2
130#define  PCIE_PHY_MPLL_MULTIPLIER_MASK		0x7f
131#define  PCIE_PHY_MPLL_MULTIPLIER_OVRD		BIT(9)
132
133#define PCIE_PHY_RX_ASIC_OUT 0x100D
134#define PCIE_PHY_RX_ASIC_OUT_VALID	(1 << 0)
135
136/* iMX7 PCIe PHY registers */
137#define PCIE_PHY_CMN_REG4		0x14
138/* These are probably the bits that *aren't* DCC_FB_EN */
139#define PCIE_PHY_CMN_REG4_DCC_FB_EN	0x29
140
141#define PCIE_PHY_CMN_REG15	        0x54
142#define PCIE_PHY_CMN_REG15_DLY_4	BIT(2)
143#define PCIE_PHY_CMN_REG15_PLL_PD	BIT(5)
144#define PCIE_PHY_CMN_REG15_OVRD_PLL_PD	BIT(7)
145
146#define PCIE_PHY_CMN_REG24		0x90
147#define PCIE_PHY_CMN_REG24_RX_EQ	BIT(6)
148#define PCIE_PHY_CMN_REG24_RX_EQ_SEL	BIT(3)
149
150#define PCIE_PHY_CMN_REG26		0x98
151#define PCIE_PHY_CMN_REG26_ATT_MODE	0xBC
152
153#define PHY_RX_OVRD_IN_LO 0x1005
154#define PHY_RX_OVRD_IN_LO_RX_DATA_EN		BIT(5)
155#define PHY_RX_OVRD_IN_LO_RX_PLL_EN		BIT(3)
156
157static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
158{
159	WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ &&
160		imx6_pcie->drvdata->variant != IMX8MQ_EP &&
161		imx6_pcie->drvdata->variant != IMX8MM &&
162		imx6_pcie->drvdata->variant != IMX8MM_EP &&
163		imx6_pcie->drvdata->variant != IMX8MP &&
164		imx6_pcie->drvdata->variant != IMX8MP_EP);
165	return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14;
166}
167
168static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie)
169{
170	unsigned int mask, val, mode;
171
172	if (imx6_pcie->drvdata->mode == DW_PCIE_EP_TYPE)
173		mode = PCI_EXP_TYPE_ENDPOINT;
174	else
175		mode = PCI_EXP_TYPE_ROOT_PORT;
176
177	switch (imx6_pcie->drvdata->variant) {
178	case IMX8MQ:
179	case IMX8MQ_EP:
180		if (imx6_pcie->controller_id == 1) {
181			mask = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE;
182			val  = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
183					  mode);
184		} else {
185			mask = IMX6Q_GPR12_DEVICE_TYPE;
186			val  = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE, mode);
187		}
188		break;
189	default:
190		mask = IMX6Q_GPR12_DEVICE_TYPE;
191		val  = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE, mode);
192		break;
193	}
194
195	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val);
196}
197
198static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, bool exp_val)
199{
200	struct dw_pcie *pci = imx6_pcie->pci;
201	bool val;
202	u32 max_iterations = 10;
203	u32 wait_counter = 0;
204
205	do {
206		val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT) &
207			PCIE_PHY_STAT_ACK;
208		wait_counter++;
209
210		if (val == exp_val)
211			return 0;
212
213		udelay(1);
214	} while (wait_counter < max_iterations);
215
216	return -ETIMEDOUT;
217}
218
219static int pcie_phy_wait_ack(struct imx6_pcie *imx6_pcie, int addr)
220{
221	struct dw_pcie *pci = imx6_pcie->pci;
222	u32 val;
223	int ret;
224
225	val = PCIE_PHY_CTRL_DATA(addr);
226	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
227
228	val |= PCIE_PHY_CTRL_CAP_ADR;
229	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
230
231	ret = pcie_phy_poll_ack(imx6_pcie, true);
232	if (ret)
233		return ret;
234
235	val = PCIE_PHY_CTRL_DATA(addr);
236	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
237
238	return pcie_phy_poll_ack(imx6_pcie, false);
239}
240
241/* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
242static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int addr, u16 *data)
243{
244	struct dw_pcie *pci = imx6_pcie->pci;
245	u32 phy_ctl;
246	int ret;
247
248	ret = pcie_phy_wait_ack(imx6_pcie, addr);
249	if (ret)
250		return ret;
251
252	/* assert Read signal */
253	phy_ctl = PCIE_PHY_CTRL_RD;
254	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, phy_ctl);
255
256	ret = pcie_phy_poll_ack(imx6_pcie, true);
257	if (ret)
258		return ret;
259
260	*data = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT);
261
262	/* deassert Read signal */
263	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x00);
264
265	return pcie_phy_poll_ack(imx6_pcie, false);
266}
267
268static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, u16 data)
269{
270	struct dw_pcie *pci = imx6_pcie->pci;
271	u32 var;
272	int ret;
273
274	/* write addr */
275	/* cap addr */
276	ret = pcie_phy_wait_ack(imx6_pcie, addr);
277	if (ret)
278		return ret;
279
280	var = PCIE_PHY_CTRL_DATA(data);
281	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
282
283	/* capture data */
284	var |= PCIE_PHY_CTRL_CAP_DAT;
285	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
286
287	ret = pcie_phy_poll_ack(imx6_pcie, true);
288	if (ret)
289		return ret;
290
291	/* deassert cap data */
292	var = PCIE_PHY_CTRL_DATA(data);
293	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
294
295	/* wait for ack de-assertion */
296	ret = pcie_phy_poll_ack(imx6_pcie, false);
297	if (ret)
298		return ret;
299
300	/* assert wr signal */
301	var = PCIE_PHY_CTRL_WR;
302	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
303
304	/* wait for ack */
305	ret = pcie_phy_poll_ack(imx6_pcie, true);
306	if (ret)
307		return ret;
308
309	/* deassert wr signal */
310	var = PCIE_PHY_CTRL_DATA(data);
311	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
312
313	/* wait for ack de-assertion */
314	ret = pcie_phy_poll_ack(imx6_pcie, false);
315	if (ret)
316		return ret;
317
318	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x0);
319
320	return 0;
321}
322
323static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
324{
325	switch (imx6_pcie->drvdata->variant) {
326	case IMX8MM:
327	case IMX8MM_EP:
328	case IMX8MP:
329	case IMX8MP_EP:
330		/*
331		 * The PHY initialization had been done in the PHY
332		 * driver, break here directly.
333		 */
334		break;
335	case IMX8MQ:
336	case IMX8MQ_EP:
337		/*
338		 * TODO: Currently this code assumes external
339		 * oscillator is being used
340		 */
341		regmap_update_bits(imx6_pcie->iomuxc_gpr,
342				   imx6_pcie_grp_offset(imx6_pcie),
343				   IMX8MQ_GPR_PCIE_REF_USE_PAD,
344				   IMX8MQ_GPR_PCIE_REF_USE_PAD);
345		/*
346		 * Regarding the datasheet, the PCIE_VPH is suggested
347		 * to be 1.8V. If the PCIE_VPH is supplied by 3.3V, the
348		 * VREG_BYPASS should be cleared to zero.
349		 */
350		if (imx6_pcie->vph &&
351		    regulator_get_voltage(imx6_pcie->vph) > 3000000)
352			regmap_update_bits(imx6_pcie->iomuxc_gpr,
353					   imx6_pcie_grp_offset(imx6_pcie),
354					   IMX8MQ_GPR_PCIE_VREG_BYPASS,
355					   0);
356		break;
357	case IMX7D:
358		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
359				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
360		break;
361	case IMX6SX:
362		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
363				   IMX6SX_GPR12_PCIE_RX_EQ_MASK,
364				   IMX6SX_GPR12_PCIE_RX_EQ_2);
365		fallthrough;
366	default:
367		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
368				   IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
369
370		/* configure constant input signal to the pcie ctrl and phy */
371		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
372				   IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
373
374		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
375				   IMX6Q_GPR8_TX_DEEMPH_GEN1,
376				   imx6_pcie->tx_deemph_gen1 << 0);
377		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
378				   IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
379				   imx6_pcie->tx_deemph_gen2_3p5db << 6);
380		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
381				   IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
382				   imx6_pcie->tx_deemph_gen2_6db << 12);
383		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
384				   IMX6Q_GPR8_TX_SWING_FULL,
385				   imx6_pcie->tx_swing_full << 18);
386		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
387				   IMX6Q_GPR8_TX_SWING_LOW,
388				   imx6_pcie->tx_swing_low << 25);
389		break;
390	}
391
392	imx6_pcie_configure_type(imx6_pcie);
393}
394
395static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)
396{
397	u32 val;
398	struct device *dev = imx6_pcie->pci->dev;
399
400	if (regmap_read_poll_timeout(imx6_pcie->iomuxc_gpr,
401				     IOMUXC_GPR22, val,
402				     val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED,
403				     PHY_PLL_LOCK_WAIT_USLEEP_MAX,
404				     PHY_PLL_LOCK_WAIT_TIMEOUT))
405		dev_err(dev, "PCIe PLL lock timeout\n");
406}
407
408static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
409{
410	unsigned long phy_rate = clk_get_rate(imx6_pcie->pcie_phy);
411	int mult, div;
412	u16 val;
413
414	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
415		return 0;
416
417	switch (phy_rate) {
418	case 125000000:
419		/*
420		 * The default settings of the MPLL are for a 125MHz input
421		 * clock, so no need to reconfigure anything in that case.
422		 */
423		return 0;
424	case 100000000:
425		mult = 25;
426		div = 0;
427		break;
428	case 200000000:
429		mult = 25;
430		div = 1;
431		break;
432	default:
433		dev_err(imx6_pcie->pci->dev,
434			"Unsupported PHY reference clock rate %lu\n", phy_rate);
435		return -EINVAL;
436	}
437
438	pcie_phy_read(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, &val);
439	val &= ~(PCIE_PHY_MPLL_MULTIPLIER_MASK <<
440		 PCIE_PHY_MPLL_MULTIPLIER_SHIFT);
441	val |= mult << PCIE_PHY_MPLL_MULTIPLIER_SHIFT;
442	val |= PCIE_PHY_MPLL_MULTIPLIER_OVRD;
443	pcie_phy_write(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, val);
444
445	pcie_phy_read(imx6_pcie, PCIE_PHY_ATEOVRD, &val);
446	val &= ~(PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK <<
447		 PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT);
448	val |= div << PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT;
449	val |= PCIE_PHY_ATEOVRD_EN;
450	pcie_phy_write(imx6_pcie, PCIE_PHY_ATEOVRD, val);
451
452	return 0;
453}
454
455static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
456{
457	u16 tmp;
458
459	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
460		return;
461
462	pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
463	tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
464		PHY_RX_OVRD_IN_LO_RX_PLL_EN);
465	pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
466
467	usleep_range(2000, 3000);
468
469	pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
470	tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
471		  PHY_RX_OVRD_IN_LO_RX_PLL_EN);
472	pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
473}
474
475#ifdef CONFIG_ARM
476/*  Added for PCI abort handling */
477static int imx6q_pcie_abort_handler(unsigned long addr,
478		unsigned int fsr, struct pt_regs *regs)
479{
480	unsigned long pc = instruction_pointer(regs);
481	unsigned long instr = *(unsigned long *)pc;
482	int reg = (instr >> 12) & 15;
483
484	/*
485	 * If the instruction being executed was a read,
486	 * make it look like it read all-ones.
487	 */
488	if ((instr & 0x0c100000) == 0x04100000) {
489		unsigned long val;
490
491		if (instr & 0x00400000)
492			val = 255;
493		else
494			val = -1;
495
496		regs->uregs[reg] = val;
497		regs->ARM_pc += 4;
498		return 0;
499	}
500
501	if ((instr & 0x0e100090) == 0x00100090) {
502		regs->uregs[reg] = -1;
503		regs->ARM_pc += 4;
504		return 0;
505	}
506
507	return 1;
508}
509#endif
510
511static int imx6_pcie_attach_pd(struct device *dev)
512{
513	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
514	struct device_link *link;
515
516	/* Do nothing when in a single power domain */
517	if (dev->pm_domain)
518		return 0;
519
520	imx6_pcie->pd_pcie = dev_pm_domain_attach_by_name(dev, "pcie");
521	if (IS_ERR(imx6_pcie->pd_pcie))
522		return PTR_ERR(imx6_pcie->pd_pcie);
523	/* Do nothing when power domain missing */
524	if (!imx6_pcie->pd_pcie)
525		return 0;
526	link = device_link_add(dev, imx6_pcie->pd_pcie,
527			DL_FLAG_STATELESS |
528			DL_FLAG_PM_RUNTIME |
529			DL_FLAG_RPM_ACTIVE);
530	if (!link) {
531		dev_err(dev, "Failed to add device_link to pcie pd.\n");
532		return -EINVAL;
533	}
534
535	imx6_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy");
536	if (IS_ERR(imx6_pcie->pd_pcie_phy))
537		return PTR_ERR(imx6_pcie->pd_pcie_phy);
538
539	link = device_link_add(dev, imx6_pcie->pd_pcie_phy,
540			DL_FLAG_STATELESS |
541			DL_FLAG_PM_RUNTIME |
542			DL_FLAG_RPM_ACTIVE);
543	if (!link) {
544		dev_err(dev, "Failed to add device_link to pcie_phy pd.\n");
545		return -EINVAL;
546	}
547
548	return 0;
549}
550
551static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
552{
553	struct dw_pcie *pci = imx6_pcie->pci;
554	struct device *dev = pci->dev;
555	unsigned int offset;
556	int ret = 0;
557
558	switch (imx6_pcie->drvdata->variant) {
559	case IMX6SX:
560		ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
561		if (ret) {
562			dev_err(dev, "unable to enable pcie_axi clock\n");
563			break;
564		}
565
566		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
567				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
568		break;
569	case IMX6QP:
570	case IMX6Q:
571		/* power up core phy and enable ref clock */
572		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
573				   IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
574		/*
575		 * the async reset input need ref clock to sync internally,
576		 * when the ref clock comes after reset, internal synced
577		 * reset time is too short, cannot meet the requirement.
578		 * add one ~10us delay here.
579		 */
580		usleep_range(10, 100);
581		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
582				   IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
583		break;
584	case IMX7D:
585		break;
586	case IMX8MM:
587	case IMX8MM_EP:
588	case IMX8MQ:
589	case IMX8MQ_EP:
590	case IMX8MP:
591	case IMX8MP_EP:
592		ret = clk_prepare_enable(imx6_pcie->pcie_aux);
593		if (ret) {
594			dev_err(dev, "unable to enable pcie_aux clock\n");
595			break;
596		}
597
598		offset = imx6_pcie_grp_offset(imx6_pcie);
599		/*
600		 * Set the over ride low and enabled
601		 * make sure that REF_CLK is turned on.
602		 */
603		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
604				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE,
605				   0);
606		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
607				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
608				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
609		break;
610	}
611
612	return ret;
613}
614
615static void imx6_pcie_disable_ref_clk(struct imx6_pcie *imx6_pcie)
616{
617	switch (imx6_pcie->drvdata->variant) {
618	case IMX6SX:
619		clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
620		break;
621	case IMX6QP:
622	case IMX6Q:
623		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
624				IMX6Q_GPR1_PCIE_REF_CLK_EN, 0);
625		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
626				IMX6Q_GPR1_PCIE_TEST_PD,
627				IMX6Q_GPR1_PCIE_TEST_PD);
628		break;
629	case IMX7D:
630		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
631				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
632				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
633		break;
634	case IMX8MM:
635	case IMX8MM_EP:
636	case IMX8MQ:
637	case IMX8MQ_EP:
638	case IMX8MP:
639	case IMX8MP_EP:
640		clk_disable_unprepare(imx6_pcie->pcie_aux);
641		break;
642	default:
643		break;
644	}
645}
646
647static int imx6_pcie_clk_enable(struct imx6_pcie *imx6_pcie)
648{
649	struct dw_pcie *pci = imx6_pcie->pci;
650	struct device *dev = pci->dev;
651	int ret;
652
653	ret = clk_prepare_enable(imx6_pcie->pcie_phy);
654	if (ret) {
655		dev_err(dev, "unable to enable pcie_phy clock\n");
656		return ret;
657	}
658
659	ret = clk_prepare_enable(imx6_pcie->pcie_bus);
660	if (ret) {
661		dev_err(dev, "unable to enable pcie_bus clock\n");
662		goto err_pcie_bus;
663	}
664
665	ret = clk_prepare_enable(imx6_pcie->pcie);
666	if (ret) {
667		dev_err(dev, "unable to enable pcie clock\n");
668		goto err_pcie;
669	}
670
671	ret = imx6_pcie_enable_ref_clk(imx6_pcie);
672	if (ret) {
673		dev_err(dev, "unable to enable pcie ref clock\n");
674		goto err_ref_clk;
675	}
676
677	/* allow the clocks to stabilize */
678	usleep_range(200, 500);
679	return 0;
680
681err_ref_clk:
682	clk_disable_unprepare(imx6_pcie->pcie);
683err_pcie:
684	clk_disable_unprepare(imx6_pcie->pcie_bus);
685err_pcie_bus:
686	clk_disable_unprepare(imx6_pcie->pcie_phy);
687
688	return ret;
689}
690
691static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
692{
693	imx6_pcie_disable_ref_clk(imx6_pcie);
694	clk_disable_unprepare(imx6_pcie->pcie);
695	clk_disable_unprepare(imx6_pcie->pcie_bus);
696	clk_disable_unprepare(imx6_pcie->pcie_phy);
697}
698
699static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
700{
701	switch (imx6_pcie->drvdata->variant) {
702	case IMX7D:
703	case IMX8MQ:
704	case IMX8MQ_EP:
705		reset_control_assert(imx6_pcie->pciephy_reset);
706		fallthrough;
707	case IMX8MM:
708	case IMX8MM_EP:
709	case IMX8MP:
710	case IMX8MP_EP:
711		reset_control_assert(imx6_pcie->apps_reset);
712		break;
713	case IMX6SX:
714		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
715				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
716				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
717		/* Force PCIe PHY reset */
718		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
719				   IMX6SX_GPR5_PCIE_BTNRST_RESET,
720				   IMX6SX_GPR5_PCIE_BTNRST_RESET);
721		break;
722	case IMX6QP:
723		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
724				   IMX6Q_GPR1_PCIE_SW_RST,
725				   IMX6Q_GPR1_PCIE_SW_RST);
726		break;
727	case IMX6Q:
728		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
729				   IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
730		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
731				   IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
732		break;
733	}
734
735	/* Some boards don't have PCIe reset GPIO. */
736	if (gpio_is_valid(imx6_pcie->reset_gpio))
737		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
738					imx6_pcie->gpio_active_high);
739}
740
741static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
742{
743	struct dw_pcie *pci = imx6_pcie->pci;
744	struct device *dev = pci->dev;
745
746	switch (imx6_pcie->drvdata->variant) {
747	case IMX8MQ:
748	case IMX8MQ_EP:
749		reset_control_deassert(imx6_pcie->pciephy_reset);
750		break;
751	case IMX7D:
752		reset_control_deassert(imx6_pcie->pciephy_reset);
753
754		/* Workaround for ERR010728, failure of PCI-e PLL VCO to
755		 * oscillate, especially when cold.  This turns off "Duty-cycle
756		 * Corrector" and other mysterious undocumented things.
757		 */
758		if (likely(imx6_pcie->phy_base)) {
759			/* De-assert DCC_FB_EN */
760			writel(PCIE_PHY_CMN_REG4_DCC_FB_EN,
761			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG4);
762			/* Assert RX_EQS and RX_EQS_SEL */
763			writel(PCIE_PHY_CMN_REG24_RX_EQ_SEL
764				| PCIE_PHY_CMN_REG24_RX_EQ,
765			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG24);
766			/* Assert ATT_MODE */
767			writel(PCIE_PHY_CMN_REG26_ATT_MODE,
768			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG26);
769		} else {
770			dev_warn(dev, "Unable to apply ERR010728 workaround. DT missing fsl,imx7d-pcie-phy phandle ?\n");
771		}
772
773		imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
774		break;
775	case IMX6SX:
776		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
777				   IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
778		break;
779	case IMX6QP:
780		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
781				   IMX6Q_GPR1_PCIE_SW_RST, 0);
782
783		usleep_range(200, 500);
784		break;
785	case IMX6Q:		/* Nothing to do */
786	case IMX8MM:
787	case IMX8MM_EP:
788	case IMX8MP:
789	case IMX8MP_EP:
790		break;
791	}
792
793	/* Some boards don't have PCIe reset GPIO. */
794	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
795		msleep(100);
796		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
797					!imx6_pcie->gpio_active_high);
798		/* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
799		msleep(100);
800	}
801
802	return 0;
803}
804
805static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie)
806{
807	struct dw_pcie *pci = imx6_pcie->pci;
808	struct device *dev = pci->dev;
809	u32 tmp;
810	unsigned int retries;
811
812	for (retries = 0; retries < 200; retries++) {
813		tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
814		/* Test if the speed change finished. */
815		if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
816			return 0;
817		usleep_range(100, 1000);
818	}
819
820	dev_err(dev, "Speed change timeout\n");
821	return -ETIMEDOUT;
822}
823
824static void imx6_pcie_ltssm_enable(struct device *dev)
825{
826	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
827
828	switch (imx6_pcie->drvdata->variant) {
829	case IMX6Q:
830	case IMX6SX:
831	case IMX6QP:
832		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
833				   IMX6Q_GPR12_PCIE_CTL_2,
834				   IMX6Q_GPR12_PCIE_CTL_2);
835		break;
836	case IMX7D:
837	case IMX8MQ:
838	case IMX8MQ_EP:
839	case IMX8MM:
840	case IMX8MM_EP:
841	case IMX8MP:
842	case IMX8MP_EP:
843		reset_control_deassert(imx6_pcie->apps_reset);
844		break;
845	}
846}
847
848static void imx6_pcie_ltssm_disable(struct device *dev)
849{
850	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
851
852	switch (imx6_pcie->drvdata->variant) {
853	case IMX6Q:
854	case IMX6SX:
855	case IMX6QP:
856		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
857				   IMX6Q_GPR12_PCIE_CTL_2, 0);
858		break;
859	case IMX7D:
860	case IMX8MQ:
861	case IMX8MQ_EP:
862	case IMX8MM:
863	case IMX8MM_EP:
864	case IMX8MP:
865	case IMX8MP_EP:
866		reset_control_assert(imx6_pcie->apps_reset);
867		break;
868	}
869}
870
871static int imx6_pcie_start_link(struct dw_pcie *pci)
872{
873	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
874	struct device *dev = pci->dev;
875	u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
876	u32 tmp;
877	int ret;
878
879	/*
880	 * Force Gen1 operation when starting the link.  In case the link is
881	 * started in Gen2 mode, there is a possibility the devices on the
882	 * bus will not be detected at all.  This happens with PCIe switches.
883	 */
884	dw_pcie_dbi_ro_wr_en(pci);
885	tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
886	tmp &= ~PCI_EXP_LNKCAP_SLS;
887	tmp |= PCI_EXP_LNKCAP_SLS_2_5GB;
888	dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
889	dw_pcie_dbi_ro_wr_dis(pci);
890
891	/* Start LTSSM. */
892	imx6_pcie_ltssm_enable(dev);
893
894	ret = dw_pcie_wait_for_link(pci);
895	if (ret)
896		goto err_reset_phy;
897
898	if (pci->link_gen > 1) {
899		/* Allow faster modes after the link is up */
900		dw_pcie_dbi_ro_wr_en(pci);
901		tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
902		tmp &= ~PCI_EXP_LNKCAP_SLS;
903		tmp |= pci->link_gen;
904		dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
905
906		/*
907		 * Start Directed Speed Change so the best possible
908		 * speed both link partners support can be negotiated.
909		 */
910		tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
911		tmp |= PORT_LOGIC_SPEED_CHANGE;
912		dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
913		dw_pcie_dbi_ro_wr_dis(pci);
914
915		if (imx6_pcie->drvdata->flags &
916		    IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE) {
917			/*
918			 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
919			 * from i.MX6 family when no link speed transition
920			 * occurs and we go Gen1 -> yep, Gen1. The difference
921			 * is that, in such case, it will not be cleared by HW
922			 * which will cause the following code to report false
923			 * failure.
924			 */
925
926			ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
927			if (ret) {
928				dev_err(dev, "Failed to bring link up!\n");
929				goto err_reset_phy;
930			}
931		}
932
933		/* Make sure link training is finished as well! */
934		ret = dw_pcie_wait_for_link(pci);
935		if (ret)
936			goto err_reset_phy;
937	} else {
938		dev_info(dev, "Link: Only Gen1 is enabled\n");
939	}
940
941	imx6_pcie->link_is_up = true;
942	tmp = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA);
943	dev_info(dev, "Link up, Gen%i\n", tmp & PCI_EXP_LNKSTA_CLS);
944	return 0;
945
946err_reset_phy:
947	imx6_pcie->link_is_up = false;
948	dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
949		dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0),
950		dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1));
951	imx6_pcie_reset_phy(imx6_pcie);
952	return 0;
953}
954
955static void imx6_pcie_stop_link(struct dw_pcie *pci)
956{
957	struct device *dev = pci->dev;
958
959	/* Turn off PCIe LTSSM */
960	imx6_pcie_ltssm_disable(dev);
961}
962
963static int imx6_pcie_host_init(struct dw_pcie_rp *pp)
964{
965	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
966	struct device *dev = pci->dev;
967	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
968	int ret;
969
970	if (imx6_pcie->vpcie) {
971		ret = regulator_enable(imx6_pcie->vpcie);
972		if (ret) {
973			dev_err(dev, "failed to enable vpcie regulator: %d\n",
974				ret);
975			return ret;
976		}
977	}
978
979	imx6_pcie_assert_core_reset(imx6_pcie);
980	imx6_pcie_init_phy(imx6_pcie);
981
982	ret = imx6_pcie_clk_enable(imx6_pcie);
983	if (ret) {
984		dev_err(dev, "unable to enable pcie clocks: %d\n", ret);
985		goto err_reg_disable;
986	}
987
988	if (imx6_pcie->phy) {
989		ret = phy_init(imx6_pcie->phy);
990		if (ret) {
991			dev_err(dev, "pcie PHY power up failed\n");
992			goto err_clk_disable;
993		}
994	}
995
996	if (imx6_pcie->phy) {
997		ret = phy_power_on(imx6_pcie->phy);
998		if (ret) {
999			dev_err(dev, "waiting for PHY ready timeout!\n");
1000			goto err_phy_off;
1001		}
1002	}
1003
1004	ret = imx6_pcie_deassert_core_reset(imx6_pcie);
1005	if (ret < 0) {
1006		dev_err(dev, "pcie deassert core reset failed: %d\n", ret);
1007		goto err_phy_off;
1008	}
1009
1010	imx6_setup_phy_mpll(imx6_pcie);
1011
1012	return 0;
1013
1014err_phy_off:
1015	if (imx6_pcie->phy)
1016		phy_exit(imx6_pcie->phy);
1017err_clk_disable:
1018	imx6_pcie_clk_disable(imx6_pcie);
1019err_reg_disable:
1020	if (imx6_pcie->vpcie)
1021		regulator_disable(imx6_pcie->vpcie);
1022	return ret;
1023}
1024
1025static void imx6_pcie_host_exit(struct dw_pcie_rp *pp)
1026{
1027	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1028	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
1029
1030	if (imx6_pcie->phy) {
1031		if (phy_power_off(imx6_pcie->phy))
1032			dev_err(pci->dev, "unable to power off PHY\n");
1033		phy_exit(imx6_pcie->phy);
1034	}
1035	imx6_pcie_clk_disable(imx6_pcie);
1036
1037	if (imx6_pcie->vpcie)
1038		regulator_disable(imx6_pcie->vpcie);
1039}
1040
1041static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
1042	.host_init = imx6_pcie_host_init,
1043	.host_deinit = imx6_pcie_host_exit,
1044};
1045
1046static const struct dw_pcie_ops dw_pcie_ops = {
1047	.start_link = imx6_pcie_start_link,
1048	.stop_link = imx6_pcie_stop_link,
1049};
1050
1051static void imx6_pcie_ep_init(struct dw_pcie_ep *ep)
1052{
1053	enum pci_barno bar;
1054	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
1055
1056	for (bar = BAR_0; bar <= BAR_5; bar++)
1057		dw_pcie_ep_reset_bar(pci, bar);
1058}
1059
1060static int imx6_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
1061				  enum pci_epc_irq_type type,
1062				  u16 interrupt_num)
1063{
1064	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
1065
1066	switch (type) {
1067	case PCI_EPC_IRQ_LEGACY:
1068		return dw_pcie_ep_raise_legacy_irq(ep, func_no);
1069	case PCI_EPC_IRQ_MSI:
1070		return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
1071	case PCI_EPC_IRQ_MSIX:
1072		return dw_pcie_ep_raise_msix_irq(ep, func_no, interrupt_num);
1073	default:
1074		dev_err(pci->dev, "UNKNOWN IRQ type\n");
1075		return -EINVAL;
1076	}
1077
1078	return 0;
1079}
1080
1081static const struct pci_epc_features imx8m_pcie_epc_features = {
1082	.linkup_notifier = false,
1083	.msi_capable = true,
1084	.msix_capable = false,
1085	.reserved_bar = 1 << BAR_1 | 1 << BAR_3,
1086	.align = SZ_64K,
1087};
1088
1089static const struct pci_epc_features*
1090imx6_pcie_ep_get_features(struct dw_pcie_ep *ep)
1091{
1092	return &imx8m_pcie_epc_features;
1093}
1094
1095static const struct dw_pcie_ep_ops pcie_ep_ops = {
1096	.ep_init = imx6_pcie_ep_init,
1097	.raise_irq = imx6_pcie_ep_raise_irq,
1098	.get_features = imx6_pcie_ep_get_features,
1099};
1100
1101static int imx6_add_pcie_ep(struct imx6_pcie *imx6_pcie,
1102			   struct platform_device *pdev)
1103{
1104	int ret;
1105	unsigned int pcie_dbi2_offset;
1106	struct dw_pcie_ep *ep;
1107	struct resource *res;
1108	struct dw_pcie *pci = imx6_pcie->pci;
1109	struct dw_pcie_rp *pp = &pci->pp;
1110	struct device *dev = pci->dev;
1111
1112	imx6_pcie_host_init(pp);
1113	ep = &pci->ep;
1114	ep->ops = &pcie_ep_ops;
1115
1116	switch (imx6_pcie->drvdata->variant) {
1117	case IMX8MQ_EP:
1118	case IMX8MM_EP:
1119	case IMX8MP_EP:
1120		pcie_dbi2_offset = SZ_1M;
1121		break;
1122	default:
1123		pcie_dbi2_offset = SZ_4K;
1124		break;
1125	}
1126	pci->dbi_base2 = pci->dbi_base + pcie_dbi2_offset;
1127	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "addr_space");
1128	if (!res)
1129		return -EINVAL;
1130
1131	ep->phys_base = res->start;
1132	ep->addr_size = resource_size(res);
1133	ep->page_size = SZ_64K;
1134
1135	ret = dw_pcie_ep_init(ep);
1136	if (ret) {
1137		dev_err(dev, "failed to initialize endpoint\n");
1138		return ret;
1139	}
1140	/* Start LTSSM. */
1141	imx6_pcie_ltssm_enable(dev);
1142
1143	return 0;
1144}
1145
1146static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
1147{
1148	struct device *dev = imx6_pcie->pci->dev;
1149
1150	/* Some variants have a turnoff reset in DT */
1151	if (imx6_pcie->turnoff_reset) {
1152		reset_control_assert(imx6_pcie->turnoff_reset);
1153		reset_control_deassert(imx6_pcie->turnoff_reset);
1154		goto pm_turnoff_sleep;
1155	}
1156
1157	/* Others poke directly at IOMUXC registers */
1158	switch (imx6_pcie->drvdata->variant) {
1159	case IMX6SX:
1160	case IMX6QP:
1161		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
1162				IMX6SX_GPR12_PCIE_PM_TURN_OFF,
1163				IMX6SX_GPR12_PCIE_PM_TURN_OFF);
1164		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
1165				IMX6SX_GPR12_PCIE_PM_TURN_OFF, 0);
1166		break;
1167	default:
1168		dev_err(dev, "PME_Turn_Off not implemented\n");
1169		return;
1170	}
1171
1172	/*
1173	 * Components with an upstream port must respond to
1174	 * PME_Turn_Off with PME_TO_Ack but we can't check.
1175	 *
1176	 * The standard recommends a 1-10ms timeout after which to
1177	 * proceed anyway as if acks were received.
1178	 */
1179pm_turnoff_sleep:
1180	usleep_range(1000, 10000);
1181}
1182
1183static void imx6_pcie_msi_save_restore(struct imx6_pcie *imx6_pcie, bool save)
1184{
1185	u8 offset;
1186	u16 val;
1187	struct dw_pcie *pci = imx6_pcie->pci;
1188
1189	if (pci_msi_enabled()) {
1190		offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
1191		if (save) {
1192			val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
1193			imx6_pcie->msi_ctrl = val;
1194		} else {
1195			dw_pcie_dbi_ro_wr_en(pci);
1196			val = imx6_pcie->msi_ctrl;
1197			dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
1198			dw_pcie_dbi_ro_wr_dis(pci);
1199		}
1200	}
1201}
1202
1203static int imx6_pcie_suspend_noirq(struct device *dev)
1204{
1205	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
1206	struct dw_pcie_rp *pp = &imx6_pcie->pci->pp;
1207
1208	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
1209		return 0;
1210
1211	imx6_pcie_msi_save_restore(imx6_pcie, true);
1212	imx6_pcie_pm_turnoff(imx6_pcie);
1213	imx6_pcie_stop_link(imx6_pcie->pci);
1214	imx6_pcie_host_exit(pp);
1215
1216	return 0;
1217}
1218
1219static int imx6_pcie_resume_noirq(struct device *dev)
1220{
1221	int ret;
1222	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
1223	struct dw_pcie_rp *pp = &imx6_pcie->pci->pp;
1224
1225	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
1226		return 0;
1227
1228	ret = imx6_pcie_host_init(pp);
1229	if (ret)
1230		return ret;
1231	imx6_pcie_msi_save_restore(imx6_pcie, false);
1232	dw_pcie_setup_rc(pp);
1233
1234	if (imx6_pcie->link_is_up)
1235		imx6_pcie_start_link(imx6_pcie->pci);
1236
1237	return 0;
1238}
1239
1240static const struct dev_pm_ops imx6_pcie_pm_ops = {
1241	NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq,
1242				  imx6_pcie_resume_noirq)
1243};
1244
1245static int imx6_pcie_probe(struct platform_device *pdev)
1246{
1247	struct device *dev = &pdev->dev;
1248	struct dw_pcie *pci;
1249	struct imx6_pcie *imx6_pcie;
1250	struct device_node *np;
1251	struct resource *dbi_base;
1252	struct device_node *node = dev->of_node;
1253	int ret;
1254	u16 val;
1255
1256	imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
1257	if (!imx6_pcie)
1258		return -ENOMEM;
1259
1260	pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
1261	if (!pci)
1262		return -ENOMEM;
1263
1264	pci->dev = dev;
1265	pci->ops = &dw_pcie_ops;
1266	pci->pp.ops = &imx6_pcie_host_ops;
1267
1268	imx6_pcie->pci = pci;
1269	imx6_pcie->drvdata = of_device_get_match_data(dev);
1270
1271	/* Find the PHY if one is defined, only imx7d uses it */
1272	np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0);
1273	if (np) {
1274		struct resource res;
1275
1276		ret = of_address_to_resource(np, 0, &res);
1277		if (ret) {
1278			dev_err(dev, "Unable to map PCIe PHY\n");
1279			return ret;
1280		}
1281		imx6_pcie->phy_base = devm_ioremap_resource(dev, &res);
1282		if (IS_ERR(imx6_pcie->phy_base))
1283			return PTR_ERR(imx6_pcie->phy_base);
1284	}
1285
1286	pci->dbi_base = devm_platform_get_and_ioremap_resource(pdev, 0, &dbi_base);
1287	if (IS_ERR(pci->dbi_base))
1288		return PTR_ERR(pci->dbi_base);
1289
1290	/* Fetch GPIOs */
1291	imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
1292	imx6_pcie->gpio_active_high = of_property_read_bool(node,
1293						"reset-gpio-active-high");
1294	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
1295		ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
1296				imx6_pcie->gpio_active_high ?
1297					GPIOF_OUT_INIT_HIGH :
1298					GPIOF_OUT_INIT_LOW,
1299				"PCIe reset");
1300		if (ret) {
1301			dev_err(dev, "unable to get reset gpio\n");
1302			return ret;
1303		}
1304	} else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) {
1305		return imx6_pcie->reset_gpio;
1306	}
1307
1308	/* Fetch clocks */
1309	imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus");
1310	if (IS_ERR(imx6_pcie->pcie_bus))
1311		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_bus),
1312				     "pcie_bus clock source missing or invalid\n");
1313
1314	imx6_pcie->pcie = devm_clk_get(dev, "pcie");
1315	if (IS_ERR(imx6_pcie->pcie))
1316		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie),
1317				     "pcie clock source missing or invalid\n");
1318
1319	switch (imx6_pcie->drvdata->variant) {
1320	case IMX6SX:
1321		imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
1322							   "pcie_inbound_axi");
1323		if (IS_ERR(imx6_pcie->pcie_inbound_axi))
1324			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_inbound_axi),
1325					     "pcie_inbound_axi clock missing or invalid\n");
1326		break;
1327	case IMX8MQ:
1328	case IMX8MQ_EP:
1329		imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
1330		if (IS_ERR(imx6_pcie->pcie_aux))
1331			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
1332					     "pcie_aux clock source missing or invalid\n");
1333		fallthrough;
1334	case IMX7D:
1335		if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
1336			imx6_pcie->controller_id = 1;
1337
1338		imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
1339									    "pciephy");
1340		if (IS_ERR(imx6_pcie->pciephy_reset)) {
1341			dev_err(dev, "Failed to get PCIEPHY reset control\n");
1342			return PTR_ERR(imx6_pcie->pciephy_reset);
1343		}
1344
1345		imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
1346									 "apps");
1347		if (IS_ERR(imx6_pcie->apps_reset)) {
1348			dev_err(dev, "Failed to get PCIE APPS reset control\n");
1349			return PTR_ERR(imx6_pcie->apps_reset);
1350		}
1351		break;
1352	case IMX8MM:
1353	case IMX8MM_EP:
1354	case IMX8MP:
1355	case IMX8MP_EP:
1356		imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
1357		if (IS_ERR(imx6_pcie->pcie_aux))
1358			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
1359					     "pcie_aux clock source missing or invalid\n");
1360		imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
1361									 "apps");
1362		if (IS_ERR(imx6_pcie->apps_reset))
1363			return dev_err_probe(dev, PTR_ERR(imx6_pcie->apps_reset),
1364					     "failed to get pcie apps reset control\n");
1365
1366		imx6_pcie->phy = devm_phy_get(dev, "pcie-phy");
1367		if (IS_ERR(imx6_pcie->phy))
1368			return dev_err_probe(dev, PTR_ERR(imx6_pcie->phy),
1369					     "failed to get pcie phy\n");
1370
1371		break;
1372	default:
1373		break;
1374	}
1375	/* Don't fetch the pcie_phy clock, if it has abstract PHY driver */
1376	if (imx6_pcie->phy == NULL) {
1377		imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy");
1378		if (IS_ERR(imx6_pcie->pcie_phy))
1379			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_phy),
1380					     "pcie_phy clock source missing or invalid\n");
1381	}
1382
1383
1384	/* Grab turnoff reset */
1385	imx6_pcie->turnoff_reset = devm_reset_control_get_optional_exclusive(dev, "turnoff");
1386	if (IS_ERR(imx6_pcie->turnoff_reset)) {
1387		dev_err(dev, "Failed to get TURNOFF reset control\n");
1388		return PTR_ERR(imx6_pcie->turnoff_reset);
1389	}
1390
1391	/* Grab GPR config register range */
1392	imx6_pcie->iomuxc_gpr =
1393		 syscon_regmap_lookup_by_compatible(imx6_pcie->drvdata->gpr);
1394	if (IS_ERR(imx6_pcie->iomuxc_gpr)) {
1395		dev_err(dev, "unable to find iomuxc registers\n");
1396		return PTR_ERR(imx6_pcie->iomuxc_gpr);
1397	}
1398
1399	/* Grab PCIe PHY Tx Settings */
1400	if (of_property_read_u32(node, "fsl,tx-deemph-gen1",
1401				 &imx6_pcie->tx_deemph_gen1))
1402		imx6_pcie->tx_deemph_gen1 = 0;
1403
1404	if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db",
1405				 &imx6_pcie->tx_deemph_gen2_3p5db))
1406		imx6_pcie->tx_deemph_gen2_3p5db = 0;
1407
1408	if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db",
1409				 &imx6_pcie->tx_deemph_gen2_6db))
1410		imx6_pcie->tx_deemph_gen2_6db = 20;
1411
1412	if (of_property_read_u32(node, "fsl,tx-swing-full",
1413				 &imx6_pcie->tx_swing_full))
1414		imx6_pcie->tx_swing_full = 127;
1415
1416	if (of_property_read_u32(node, "fsl,tx-swing-low",
1417				 &imx6_pcie->tx_swing_low))
1418		imx6_pcie->tx_swing_low = 127;
1419
1420	/* Limit link speed */
1421	pci->link_gen = 1;
1422	of_property_read_u32(node, "fsl,max-link-speed", &pci->link_gen);
1423
1424	imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie");
1425	if (IS_ERR(imx6_pcie->vpcie)) {
1426		if (PTR_ERR(imx6_pcie->vpcie) != -ENODEV)
1427			return PTR_ERR(imx6_pcie->vpcie);
1428		imx6_pcie->vpcie = NULL;
1429	}
1430
1431	imx6_pcie->vph = devm_regulator_get_optional(&pdev->dev, "vph");
1432	if (IS_ERR(imx6_pcie->vph)) {
1433		if (PTR_ERR(imx6_pcie->vph) != -ENODEV)
1434			return PTR_ERR(imx6_pcie->vph);
1435		imx6_pcie->vph = NULL;
1436	}
1437
1438	platform_set_drvdata(pdev, imx6_pcie);
1439
1440	ret = imx6_pcie_attach_pd(dev);
1441	if (ret)
1442		return ret;
1443
1444	if (imx6_pcie->drvdata->mode == DW_PCIE_EP_TYPE) {
1445		ret = imx6_add_pcie_ep(imx6_pcie, pdev);
1446		if (ret < 0)
1447			return ret;
1448	} else {
1449		ret = dw_pcie_host_init(&pci->pp);
1450		if (ret < 0)
1451			return ret;
1452
1453		if (pci_msi_enabled()) {
1454			u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
1455
1456			val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
1457			val |= PCI_MSI_FLAGS_ENABLE;
1458			dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
1459		}
1460	}
1461
1462	return 0;
1463}
1464
1465static void imx6_pcie_shutdown(struct platform_device *pdev)
1466{
1467	struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
1468
1469	/* bring down link, so bootloader gets clean state in case of reboot */
1470	imx6_pcie_assert_core_reset(imx6_pcie);
1471}
1472
1473static const struct imx6_pcie_drvdata drvdata[] = {
1474	[IMX6Q] = {
1475		.variant = IMX6Q,
1476		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1477			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1478		.dbi_length = 0x200,
1479		.gpr = "fsl,imx6q-iomuxc-gpr",
1480	},
1481	[IMX6SX] = {
1482		.variant = IMX6SX,
1483		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1484			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
1485			 IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1486		.gpr = "fsl,imx6q-iomuxc-gpr",
1487	},
1488	[IMX6QP] = {
1489		.variant = IMX6QP,
1490		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1491			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
1492			 IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1493		.dbi_length = 0x200,
1494		.gpr = "fsl,imx6q-iomuxc-gpr",
1495	},
1496	[IMX7D] = {
1497		.variant = IMX7D,
1498		.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1499		.gpr = "fsl,imx7d-iomuxc-gpr",
1500	},
1501	[IMX8MQ] = {
1502		.variant = IMX8MQ,
1503		.gpr = "fsl,imx8mq-iomuxc-gpr",
1504	},
1505	[IMX8MM] = {
1506		.variant = IMX8MM,
1507		.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1508		.gpr = "fsl,imx8mm-iomuxc-gpr",
1509	},
1510	[IMX8MP] = {
1511		.variant = IMX8MP,
1512		.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1513		.gpr = "fsl,imx8mp-iomuxc-gpr",
1514	},
1515	[IMX8MQ_EP] = {
1516		.variant = IMX8MQ_EP,
1517		.mode = DW_PCIE_EP_TYPE,
1518		.gpr = "fsl,imx8mq-iomuxc-gpr",
1519	},
1520	[IMX8MM_EP] = {
1521		.variant = IMX8MM_EP,
1522		.mode = DW_PCIE_EP_TYPE,
1523		.gpr = "fsl,imx8mm-iomuxc-gpr",
1524	},
1525	[IMX8MP_EP] = {
1526		.variant = IMX8MP_EP,
1527		.mode = DW_PCIE_EP_TYPE,
1528		.gpr = "fsl,imx8mp-iomuxc-gpr",
1529	},
1530};
1531
1532static const struct of_device_id imx6_pcie_of_match[] = {
1533	{ .compatible = "fsl,imx6q-pcie",  .data = &drvdata[IMX6Q],  },
1534	{ .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], },
1535	{ .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], },
1536	{ .compatible = "fsl,imx7d-pcie",  .data = &drvdata[IMX7D],  },
1537	{ .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], },
1538	{ .compatible = "fsl,imx8mm-pcie", .data = &drvdata[IMX8MM], },
1539	{ .compatible = "fsl,imx8mp-pcie", .data = &drvdata[IMX8MP], },
1540	{ .compatible = "fsl,imx8mq-pcie-ep", .data = &drvdata[IMX8MQ_EP], },
1541	{ .compatible = "fsl,imx8mm-pcie-ep", .data = &drvdata[IMX8MM_EP], },
1542	{ .compatible = "fsl,imx8mp-pcie-ep", .data = &drvdata[IMX8MP_EP], },
1543	{},
1544};
1545
1546static struct platform_driver imx6_pcie_driver = {
1547	.driver = {
1548		.name	= "imx6q-pcie",
1549		.of_match_table = imx6_pcie_of_match,
1550		.suppress_bind_attrs = true,
1551		.pm = &imx6_pcie_pm_ops,
1552		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1553	},
1554	.probe    = imx6_pcie_probe,
1555	.shutdown = imx6_pcie_shutdown,
1556};
1557
1558static void imx6_pcie_quirk(struct pci_dev *dev)
1559{
1560	struct pci_bus *bus = dev->bus;
1561	struct dw_pcie_rp *pp = bus->sysdata;
1562
1563	/* Bus parent is the PCI bridge, its parent is this platform driver */
1564	if (!bus->dev.parent || !bus->dev.parent->parent)
1565		return;
1566
1567	/* Make sure we only quirk devices associated with this driver */
1568	if (bus->dev.parent->parent->driver != &imx6_pcie_driver.driver)
1569		return;
1570
1571	if (pci_is_root_bus(bus)) {
1572		struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1573		struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
1574
1575		/*
1576		 * Limit config length to avoid the kernel reading beyond
1577		 * the register set and causing an abort on i.MX 6Quad
1578		 */
1579		if (imx6_pcie->drvdata->dbi_length) {
1580			dev->cfg_size = imx6_pcie->drvdata->dbi_length;
1581			dev_info(&dev->dev, "Limiting cfg_size to %d\n",
1582					dev->cfg_size);
1583		}
1584	}
1585}
1586DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_SYNOPSYS, 0xabcd,
1587			PCI_CLASS_BRIDGE_PCI, 8, imx6_pcie_quirk);
1588
1589static int __init imx6_pcie_init(void)
1590{
1591#ifdef CONFIG_ARM
1592	struct device_node *np;
1593
1594	np = of_find_matching_node(NULL, imx6_pcie_of_match);
1595	if (!np)
1596		return -ENODEV;
1597	of_node_put(np);
1598
1599	/*
1600	 * Since probe() can be deferred we need to make sure that
1601	 * hook_fault_code is not called after __init memory is freed
1602	 * by kernel and since imx6q_pcie_abort_handler() is a no-op,
1603	 * we can install the handler here without risking it
1604	 * accessing some uninitialized driver state.
1605	 */
1606	hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0,
1607			"external abort on non-linefetch");
1608#endif
1609
1610	return platform_driver_register(&imx6_pcie_driver);
1611}
1612device_initcall(imx6_pcie_init);
1613