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/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 
47 enum imx6_pcie_variants {
48 	IMX6Q,
49 	IMX6SX,
50 	IMX6QP,
51 	IMX7D,
52 	IMX8MQ,
53 	IMX8MM,
54 };
55 
56 #define IMX6_PCIE_FLAG_IMX6_PHY			BIT(0)
57 #define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE	BIT(1)
58 #define IMX6_PCIE_FLAG_SUPPORTS_SUSPEND		BIT(2)
59 
60 struct imx6_pcie_drvdata {
61 	enum imx6_pcie_variants variant;
62 	u32 flags;
63 	int dbi_length;
64 };
65 
66 struct imx6_pcie {
67 	struct dw_pcie		*pci;
68 	int			reset_gpio;
69 	bool			gpio_active_high;
70 	struct clk		*pcie_bus;
71 	struct clk		*pcie_phy;
72 	struct clk		*pcie_inbound_axi;
73 	struct clk		*pcie;
74 	struct clk		*pcie_aux;
75 	struct regmap		*iomuxc_gpr;
76 	u32			controller_id;
77 	struct reset_control	*pciephy_reset;
78 	struct reset_control	*apps_reset;
79 	struct reset_control	*turnoff_reset;
80 	u32			tx_deemph_gen1;
81 	u32			tx_deemph_gen2_3p5db;
82 	u32			tx_deemph_gen2_6db;
83 	u32			tx_swing_full;
84 	u32			tx_swing_low;
85 	struct regulator	*vpcie;
86 	struct regulator	*vph;
87 	void __iomem		*phy_base;
88 
89 	/* power domain for pcie */
90 	struct device		*pd_pcie;
91 	/* power domain for pcie phy */
92 	struct device		*pd_pcie_phy;
93 	struct phy		*phy;
94 	const struct imx6_pcie_drvdata *drvdata;
95 };
96 
97 /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
98 #define PHY_PLL_LOCK_WAIT_USLEEP_MAX	200
99 #define PHY_PLL_LOCK_WAIT_TIMEOUT	(2000 * PHY_PLL_LOCK_WAIT_USLEEP_MAX)
100 
101 /* PCIe Port Logic registers (memory-mapped) */
102 #define PL_OFFSET 0x700
103 
104 #define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
105 #define PCIE_PHY_CTRL_DATA(x)		FIELD_PREP(GENMASK(15, 0), (x))
106 #define PCIE_PHY_CTRL_CAP_ADR		BIT(16)
107 #define PCIE_PHY_CTRL_CAP_DAT		BIT(17)
108 #define PCIE_PHY_CTRL_WR		BIT(18)
109 #define PCIE_PHY_CTRL_RD		BIT(19)
110 
111 #define PCIE_PHY_STAT (PL_OFFSET + 0x110)
112 #define PCIE_PHY_STAT_ACK		BIT(16)
113 
114 /* PHY registers (not memory-mapped) */
115 #define PCIE_PHY_ATEOVRD			0x10
116 #define  PCIE_PHY_ATEOVRD_EN			BIT(2)
117 #define  PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT	0
118 #define  PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK	0x1
119 
120 #define PCIE_PHY_MPLL_OVRD_IN_LO		0x11
121 #define  PCIE_PHY_MPLL_MULTIPLIER_SHIFT		2
122 #define  PCIE_PHY_MPLL_MULTIPLIER_MASK		0x7f
123 #define  PCIE_PHY_MPLL_MULTIPLIER_OVRD		BIT(9)
124 
125 #define PCIE_PHY_RX_ASIC_OUT 0x100D
126 #define PCIE_PHY_RX_ASIC_OUT_VALID	(1 << 0)
127 
128 /* iMX7 PCIe PHY registers */
129 #define PCIE_PHY_CMN_REG4		0x14
130 /* These are probably the bits that *aren't* DCC_FB_EN */
131 #define PCIE_PHY_CMN_REG4_DCC_FB_EN	0x29
132 
133 #define PCIE_PHY_CMN_REG15	        0x54
134 #define PCIE_PHY_CMN_REG15_DLY_4	BIT(2)
135 #define PCIE_PHY_CMN_REG15_PLL_PD	BIT(5)
136 #define PCIE_PHY_CMN_REG15_OVRD_PLL_PD	BIT(7)
137 
138 #define PCIE_PHY_CMN_REG24		0x90
139 #define PCIE_PHY_CMN_REG24_RX_EQ	BIT(6)
140 #define PCIE_PHY_CMN_REG24_RX_EQ_SEL	BIT(3)
141 
142 #define PCIE_PHY_CMN_REG26		0x98
143 #define PCIE_PHY_CMN_REG26_ATT_MODE	0xBC
144 
145 #define PHY_RX_OVRD_IN_LO 0x1005
146 #define PHY_RX_OVRD_IN_LO_RX_DATA_EN		BIT(5)
147 #define PHY_RX_OVRD_IN_LO_RX_PLL_EN		BIT(3)
148 
149 static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, bool exp_val)
150 {
151 	struct dw_pcie *pci = imx6_pcie->pci;
152 	bool val;
153 	u32 max_iterations = 10;
154 	u32 wait_counter = 0;
155 
156 	do {
157 		val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT) &
158 			PCIE_PHY_STAT_ACK;
159 		wait_counter++;
160 
161 		if (val == exp_val)
162 			return 0;
163 
164 		udelay(1);
165 	} while (wait_counter < max_iterations);
166 
167 	return -ETIMEDOUT;
168 }
169 
170 static int pcie_phy_wait_ack(struct imx6_pcie *imx6_pcie, int addr)
171 {
172 	struct dw_pcie *pci = imx6_pcie->pci;
173 	u32 val;
174 	int ret;
175 
176 	val = PCIE_PHY_CTRL_DATA(addr);
177 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
178 
179 	val |= PCIE_PHY_CTRL_CAP_ADR;
180 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
181 
182 	ret = pcie_phy_poll_ack(imx6_pcie, true);
183 	if (ret)
184 		return ret;
185 
186 	val = PCIE_PHY_CTRL_DATA(addr);
187 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
188 
189 	return pcie_phy_poll_ack(imx6_pcie, false);
190 }
191 
192 /* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
193 static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int addr, u16 *data)
194 {
195 	struct dw_pcie *pci = imx6_pcie->pci;
196 	u32 phy_ctl;
197 	int ret;
198 
199 	ret = pcie_phy_wait_ack(imx6_pcie, addr);
200 	if (ret)
201 		return ret;
202 
203 	/* assert Read signal */
204 	phy_ctl = PCIE_PHY_CTRL_RD;
205 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, phy_ctl);
206 
207 	ret = pcie_phy_poll_ack(imx6_pcie, true);
208 	if (ret)
209 		return ret;
210 
211 	*data = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT);
212 
213 	/* deassert Read signal */
214 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x00);
215 
216 	return pcie_phy_poll_ack(imx6_pcie, false);
217 }
218 
219 static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, u16 data)
220 {
221 	struct dw_pcie *pci = imx6_pcie->pci;
222 	u32 var;
223 	int ret;
224 
225 	/* write addr */
226 	/* cap addr */
227 	ret = pcie_phy_wait_ack(imx6_pcie, addr);
228 	if (ret)
229 		return ret;
230 
231 	var = PCIE_PHY_CTRL_DATA(data);
232 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
233 
234 	/* capture data */
235 	var |= PCIE_PHY_CTRL_CAP_DAT;
236 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
237 
238 	ret = pcie_phy_poll_ack(imx6_pcie, true);
239 	if (ret)
240 		return ret;
241 
242 	/* deassert cap data */
243 	var = PCIE_PHY_CTRL_DATA(data);
244 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
245 
246 	/* wait for ack de-assertion */
247 	ret = pcie_phy_poll_ack(imx6_pcie, false);
248 	if (ret)
249 		return ret;
250 
251 	/* assert wr signal */
252 	var = PCIE_PHY_CTRL_WR;
253 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
254 
255 	/* wait for ack */
256 	ret = pcie_phy_poll_ack(imx6_pcie, true);
257 	if (ret)
258 		return ret;
259 
260 	/* deassert wr signal */
261 	var = PCIE_PHY_CTRL_DATA(data);
262 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
263 
264 	/* wait for ack de-assertion */
265 	ret = pcie_phy_poll_ack(imx6_pcie, false);
266 	if (ret)
267 		return ret;
268 
269 	dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x0);
270 
271 	return 0;
272 }
273 
274 static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
275 {
276 	u16 tmp;
277 
278 	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
279 		return;
280 
281 	pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
282 	tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
283 		PHY_RX_OVRD_IN_LO_RX_PLL_EN);
284 	pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
285 
286 	usleep_range(2000, 3000);
287 
288 	pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
289 	tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
290 		  PHY_RX_OVRD_IN_LO_RX_PLL_EN);
291 	pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
292 }
293 
294 #ifdef CONFIG_ARM
295 /*  Added for PCI abort handling */
296 static int imx6q_pcie_abort_handler(unsigned long addr,
297 		unsigned int fsr, struct pt_regs *regs)
298 {
299 	unsigned long pc = instruction_pointer(regs);
300 	unsigned long instr = *(unsigned long *)pc;
301 	int reg = (instr >> 12) & 15;
302 
303 	/*
304 	 * If the instruction being executed was a read,
305 	 * make it look like it read all-ones.
306 	 */
307 	if ((instr & 0x0c100000) == 0x04100000) {
308 		unsigned long val;
309 
310 		if (instr & 0x00400000)
311 			val = 255;
312 		else
313 			val = -1;
314 
315 		regs->uregs[reg] = val;
316 		regs->ARM_pc += 4;
317 		return 0;
318 	}
319 
320 	if ((instr & 0x0e100090) == 0x00100090) {
321 		regs->uregs[reg] = -1;
322 		regs->ARM_pc += 4;
323 		return 0;
324 	}
325 
326 	return 1;
327 }
328 #endif
329 
330 static int imx6_pcie_attach_pd(struct device *dev)
331 {
332 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
333 	struct device_link *link;
334 
335 	/* Do nothing when in a single power domain */
336 	if (dev->pm_domain)
337 		return 0;
338 
339 	imx6_pcie->pd_pcie = dev_pm_domain_attach_by_name(dev, "pcie");
340 	if (IS_ERR(imx6_pcie->pd_pcie))
341 		return PTR_ERR(imx6_pcie->pd_pcie);
342 	/* Do nothing when power domain missing */
343 	if (!imx6_pcie->pd_pcie)
344 		return 0;
345 	link = device_link_add(dev, imx6_pcie->pd_pcie,
346 			DL_FLAG_STATELESS |
347 			DL_FLAG_PM_RUNTIME |
348 			DL_FLAG_RPM_ACTIVE);
349 	if (!link) {
350 		dev_err(dev, "Failed to add device_link to pcie pd.\n");
351 		return -EINVAL;
352 	}
353 
354 	imx6_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy");
355 	if (IS_ERR(imx6_pcie->pd_pcie_phy))
356 		return PTR_ERR(imx6_pcie->pd_pcie_phy);
357 
358 	link = device_link_add(dev, imx6_pcie->pd_pcie_phy,
359 			DL_FLAG_STATELESS |
360 			DL_FLAG_PM_RUNTIME |
361 			DL_FLAG_RPM_ACTIVE);
362 	if (!link) {
363 		dev_err(dev, "Failed to add device_link to pcie_phy pd.\n");
364 		return -EINVAL;
365 	}
366 
367 	return 0;
368 }
369 
370 static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
371 {
372 	struct device *dev = imx6_pcie->pci->dev;
373 
374 	switch (imx6_pcie->drvdata->variant) {
375 	case IMX7D:
376 	case IMX8MQ:
377 		reset_control_assert(imx6_pcie->pciephy_reset);
378 		fallthrough;
379 	case IMX8MM:
380 		reset_control_assert(imx6_pcie->apps_reset);
381 		break;
382 	case IMX6SX:
383 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
384 				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
385 				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
386 		/* Force PCIe PHY reset */
387 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
388 				   IMX6SX_GPR5_PCIE_BTNRST_RESET,
389 				   IMX6SX_GPR5_PCIE_BTNRST_RESET);
390 		break;
391 	case IMX6QP:
392 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
393 				   IMX6Q_GPR1_PCIE_SW_RST,
394 				   IMX6Q_GPR1_PCIE_SW_RST);
395 		break;
396 	case IMX6Q:
397 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
398 				   IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
399 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
400 				   IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
401 		break;
402 	}
403 
404 	if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
405 		int ret = regulator_disable(imx6_pcie->vpcie);
406 
407 		if (ret)
408 			dev_err(dev, "failed to disable vpcie regulator: %d\n",
409 				ret);
410 	}
411 }
412 
413 static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
414 {
415 	WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ &&
416 		imx6_pcie->drvdata->variant != IMX8MM);
417 	return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14;
418 }
419 
420 static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
421 {
422 	struct dw_pcie *pci = imx6_pcie->pci;
423 	struct device *dev = pci->dev;
424 	unsigned int offset;
425 	int ret = 0;
426 
427 	switch (imx6_pcie->drvdata->variant) {
428 	case IMX6SX:
429 		ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
430 		if (ret) {
431 			dev_err(dev, "unable to enable pcie_axi clock\n");
432 			break;
433 		}
434 
435 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
436 				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
437 		break;
438 	case IMX6QP:
439 	case IMX6Q:
440 		/* power up core phy and enable ref clock */
441 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
442 				   IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
443 		/*
444 		 * the async reset input need ref clock to sync internally,
445 		 * when the ref clock comes after reset, internal synced
446 		 * reset time is too short, cannot meet the requirement.
447 		 * add one ~10us delay here.
448 		 */
449 		usleep_range(10, 100);
450 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
451 				   IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
452 		break;
453 	case IMX7D:
454 		break;
455 	case IMX8MM:
456 		ret = clk_prepare_enable(imx6_pcie->pcie_aux);
457 		if (ret)
458 			dev_err(dev, "unable to enable pcie_aux clock\n");
459 		break;
460 	case IMX8MQ:
461 		ret = clk_prepare_enable(imx6_pcie->pcie_aux);
462 		if (ret) {
463 			dev_err(dev, "unable to enable pcie_aux clock\n");
464 			break;
465 		}
466 
467 		offset = imx6_pcie_grp_offset(imx6_pcie);
468 		/*
469 		 * Set the over ride low and enabled
470 		 * make sure that REF_CLK is turned on.
471 		 */
472 		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
473 				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE,
474 				   0);
475 		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
476 				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
477 				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
478 		break;
479 	}
480 
481 	return ret;
482 }
483 
484 static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)
485 {
486 	u32 val;
487 	struct device *dev = imx6_pcie->pci->dev;
488 
489 	if (regmap_read_poll_timeout(imx6_pcie->iomuxc_gpr,
490 				     IOMUXC_GPR22, val,
491 				     val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED,
492 				     PHY_PLL_LOCK_WAIT_USLEEP_MAX,
493 				     PHY_PLL_LOCK_WAIT_TIMEOUT))
494 		dev_err(dev, "PCIe PLL lock timeout\n");
495 }
496 
497 static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
498 {
499 	struct dw_pcie *pci = imx6_pcie->pci;
500 	struct device *dev = pci->dev;
501 	int ret;
502 
503 	if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) {
504 		ret = regulator_enable(imx6_pcie->vpcie);
505 		if (ret) {
506 			dev_err(dev, "failed to enable vpcie regulator: %d\n",
507 				ret);
508 			return;
509 		}
510 	}
511 
512 	ret = clk_prepare_enable(imx6_pcie->pcie_phy);
513 	if (ret) {
514 		dev_err(dev, "unable to enable pcie_phy clock\n");
515 		goto err_pcie_phy;
516 	}
517 
518 	ret = clk_prepare_enable(imx6_pcie->pcie_bus);
519 	if (ret) {
520 		dev_err(dev, "unable to enable pcie_bus clock\n");
521 		goto err_pcie_bus;
522 	}
523 
524 	ret = clk_prepare_enable(imx6_pcie->pcie);
525 	if (ret) {
526 		dev_err(dev, "unable to enable pcie clock\n");
527 		goto err_pcie;
528 	}
529 
530 	ret = imx6_pcie_enable_ref_clk(imx6_pcie);
531 	if (ret) {
532 		dev_err(dev, "unable to enable pcie ref clock\n");
533 		goto err_ref_clk;
534 	}
535 
536 	switch (imx6_pcie->drvdata->variant) {
537 	case IMX8MM:
538 		if (phy_power_on(imx6_pcie->phy))
539 			dev_err(dev, "unable to power on PHY\n");
540 		break;
541 	default:
542 		break;
543 	}
544 	/* allow the clocks to stabilize */
545 	usleep_range(200, 500);
546 
547 	/* Some boards don't have PCIe reset GPIO. */
548 	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
549 		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
550 					imx6_pcie->gpio_active_high);
551 		msleep(100);
552 		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
553 					!imx6_pcie->gpio_active_high);
554 	}
555 
556 	switch (imx6_pcie->drvdata->variant) {
557 	case IMX8MQ:
558 		reset_control_deassert(imx6_pcie->pciephy_reset);
559 		break;
560 	case IMX8MM:
561 		if (phy_init(imx6_pcie->phy))
562 			dev_err(dev, "waiting for phy ready timeout!\n");
563 		break;
564 	case IMX7D:
565 		reset_control_deassert(imx6_pcie->pciephy_reset);
566 
567 		/* Workaround for ERR010728, failure of PCI-e PLL VCO to
568 		 * oscillate, especially when cold.  This turns off "Duty-cycle
569 		 * Corrector" and other mysterious undocumented things.
570 		 */
571 		if (likely(imx6_pcie->phy_base)) {
572 			/* De-assert DCC_FB_EN */
573 			writel(PCIE_PHY_CMN_REG4_DCC_FB_EN,
574 			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG4);
575 			/* Assert RX_EQS and RX_EQS_SEL */
576 			writel(PCIE_PHY_CMN_REG24_RX_EQ_SEL
577 				| PCIE_PHY_CMN_REG24_RX_EQ,
578 			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG24);
579 			/* Assert ATT_MODE */
580 			writel(PCIE_PHY_CMN_REG26_ATT_MODE,
581 			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG26);
582 		} else {
583 			dev_warn(dev, "Unable to apply ERR010728 workaround. DT missing fsl,imx7d-pcie-phy phandle ?\n");
584 		}
585 
586 		imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
587 		break;
588 	case IMX6SX:
589 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
590 				   IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
591 		break;
592 	case IMX6QP:
593 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
594 				   IMX6Q_GPR1_PCIE_SW_RST, 0);
595 
596 		usleep_range(200, 500);
597 		break;
598 	case IMX6Q:		/* Nothing to do */
599 		break;
600 	}
601 
602 	return;
603 
604 err_ref_clk:
605 	clk_disable_unprepare(imx6_pcie->pcie);
606 err_pcie:
607 	clk_disable_unprepare(imx6_pcie->pcie_bus);
608 err_pcie_bus:
609 	clk_disable_unprepare(imx6_pcie->pcie_phy);
610 err_pcie_phy:
611 	if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
612 		ret = regulator_disable(imx6_pcie->vpcie);
613 		if (ret)
614 			dev_err(dev, "failed to disable vpcie regulator: %d\n",
615 				ret);
616 	}
617 }
618 
619 static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie)
620 {
621 	unsigned int mask, val;
622 
623 	if (imx6_pcie->drvdata->variant == IMX8MQ &&
624 	    imx6_pcie->controller_id == 1) {
625 		mask   = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE;
626 		val    = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
627 				    PCI_EXP_TYPE_ROOT_PORT);
628 	} else {
629 		mask = IMX6Q_GPR12_DEVICE_TYPE;
630 		val  = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE,
631 				  PCI_EXP_TYPE_ROOT_PORT);
632 	}
633 
634 	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val);
635 }
636 
637 static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
638 {
639 	switch (imx6_pcie->drvdata->variant) {
640 	case IMX8MM:
641 		/*
642 		 * The PHY initialization had been done in the PHY
643 		 * driver, break here directly.
644 		 */
645 		break;
646 	case IMX8MQ:
647 		/*
648 		 * TODO: Currently this code assumes external
649 		 * oscillator is being used
650 		 */
651 		regmap_update_bits(imx6_pcie->iomuxc_gpr,
652 				   imx6_pcie_grp_offset(imx6_pcie),
653 				   IMX8MQ_GPR_PCIE_REF_USE_PAD,
654 				   IMX8MQ_GPR_PCIE_REF_USE_PAD);
655 		/*
656 		 * Regarding the datasheet, the PCIE_VPH is suggested
657 		 * to be 1.8V. If the PCIE_VPH is supplied by 3.3V, the
658 		 * VREG_BYPASS should be cleared to zero.
659 		 */
660 		if (imx6_pcie->vph &&
661 		    regulator_get_voltage(imx6_pcie->vph) > 3000000)
662 			regmap_update_bits(imx6_pcie->iomuxc_gpr,
663 					   imx6_pcie_grp_offset(imx6_pcie),
664 					   IMX8MQ_GPR_PCIE_VREG_BYPASS,
665 					   0);
666 		break;
667 	case IMX7D:
668 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
669 				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
670 		break;
671 	case IMX6SX:
672 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
673 				   IMX6SX_GPR12_PCIE_RX_EQ_MASK,
674 				   IMX6SX_GPR12_PCIE_RX_EQ_2);
675 		fallthrough;
676 	default:
677 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
678 				   IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
679 
680 		/* configure constant input signal to the pcie ctrl and phy */
681 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
682 				   IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
683 
684 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
685 				   IMX6Q_GPR8_TX_DEEMPH_GEN1,
686 				   imx6_pcie->tx_deemph_gen1 << 0);
687 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
688 				   IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
689 				   imx6_pcie->tx_deemph_gen2_3p5db << 6);
690 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
691 				   IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
692 				   imx6_pcie->tx_deemph_gen2_6db << 12);
693 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
694 				   IMX6Q_GPR8_TX_SWING_FULL,
695 				   imx6_pcie->tx_swing_full << 18);
696 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
697 				   IMX6Q_GPR8_TX_SWING_LOW,
698 				   imx6_pcie->tx_swing_low << 25);
699 		break;
700 	}
701 
702 	imx6_pcie_configure_type(imx6_pcie);
703 }
704 
705 static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
706 {
707 	unsigned long phy_rate = clk_get_rate(imx6_pcie->pcie_phy);
708 	int mult, div;
709 	u16 val;
710 
711 	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
712 		return 0;
713 
714 	switch (phy_rate) {
715 	case 125000000:
716 		/*
717 		 * The default settings of the MPLL are for a 125MHz input
718 		 * clock, so no need to reconfigure anything in that case.
719 		 */
720 		return 0;
721 	case 100000000:
722 		mult = 25;
723 		div = 0;
724 		break;
725 	case 200000000:
726 		mult = 25;
727 		div = 1;
728 		break;
729 	default:
730 		dev_err(imx6_pcie->pci->dev,
731 			"Unsupported PHY reference clock rate %lu\n", phy_rate);
732 		return -EINVAL;
733 	}
734 
735 	pcie_phy_read(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, &val);
736 	val &= ~(PCIE_PHY_MPLL_MULTIPLIER_MASK <<
737 		 PCIE_PHY_MPLL_MULTIPLIER_SHIFT);
738 	val |= mult << PCIE_PHY_MPLL_MULTIPLIER_SHIFT;
739 	val |= PCIE_PHY_MPLL_MULTIPLIER_OVRD;
740 	pcie_phy_write(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, val);
741 
742 	pcie_phy_read(imx6_pcie, PCIE_PHY_ATEOVRD, &val);
743 	val &= ~(PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK <<
744 		 PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT);
745 	val |= div << PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT;
746 	val |= PCIE_PHY_ATEOVRD_EN;
747 	pcie_phy_write(imx6_pcie, PCIE_PHY_ATEOVRD, val);
748 
749 	return 0;
750 }
751 
752 static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie)
753 {
754 	struct dw_pcie *pci = imx6_pcie->pci;
755 	struct device *dev = pci->dev;
756 	u32 tmp;
757 	unsigned int retries;
758 
759 	for (retries = 0; retries < 200; retries++) {
760 		tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
761 		/* Test if the speed change finished. */
762 		if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
763 			return 0;
764 		usleep_range(100, 1000);
765 	}
766 
767 	dev_err(dev, "Speed change timeout\n");
768 	return -ETIMEDOUT;
769 }
770 
771 static void imx6_pcie_ltssm_enable(struct device *dev)
772 {
773 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
774 
775 	switch (imx6_pcie->drvdata->variant) {
776 	case IMX6Q:
777 	case IMX6SX:
778 	case IMX6QP:
779 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
780 				   IMX6Q_GPR12_PCIE_CTL_2,
781 				   IMX6Q_GPR12_PCIE_CTL_2);
782 		break;
783 	case IMX7D:
784 	case IMX8MQ:
785 	case IMX8MM:
786 		reset_control_deassert(imx6_pcie->apps_reset);
787 		break;
788 	}
789 }
790 
791 static int imx6_pcie_start_link(struct dw_pcie *pci)
792 {
793 	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
794 	struct device *dev = pci->dev;
795 	u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
796 	u32 tmp;
797 	int ret;
798 
799 	/*
800 	 * Force Gen1 operation when starting the link.  In case the link is
801 	 * started in Gen2 mode, there is a possibility the devices on the
802 	 * bus will not be detected at all.  This happens with PCIe switches.
803 	 */
804 	tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
805 	tmp &= ~PCI_EXP_LNKCAP_SLS;
806 	tmp |= PCI_EXP_LNKCAP_SLS_2_5GB;
807 	dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
808 
809 	/* Start LTSSM. */
810 	imx6_pcie_ltssm_enable(dev);
811 
812 	ret = dw_pcie_wait_for_link(pci);
813 	if (ret)
814 		goto err_reset_phy;
815 
816 	if (pci->link_gen == 2) {
817 		/* Allow Gen2 mode after the link is up. */
818 		tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
819 		tmp &= ~PCI_EXP_LNKCAP_SLS;
820 		tmp |= PCI_EXP_LNKCAP_SLS_5_0GB;
821 		dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
822 
823 		/*
824 		 * Start Directed Speed Change so the best possible
825 		 * speed both link partners support can be negotiated.
826 		 */
827 		tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
828 		tmp |= PORT_LOGIC_SPEED_CHANGE;
829 		dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
830 
831 		if (imx6_pcie->drvdata->flags &
832 		    IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE) {
833 			/*
834 			 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
835 			 * from i.MX6 family when no link speed transition
836 			 * occurs and we go Gen1 -> yep, Gen1. The difference
837 			 * is that, in such case, it will not be cleared by HW
838 			 * which will cause the following code to report false
839 			 * failure.
840 			 */
841 
842 			ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
843 			if (ret) {
844 				dev_err(dev, "Failed to bring link up!\n");
845 				goto err_reset_phy;
846 			}
847 		}
848 
849 		/* Make sure link training is finished as well! */
850 		ret = dw_pcie_wait_for_link(pci);
851 		if (ret) {
852 			dev_err(dev, "Failed to bring link up!\n");
853 			goto err_reset_phy;
854 		}
855 	} else {
856 		dev_info(dev, "Link: Gen2 disabled\n");
857 	}
858 
859 	tmp = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA);
860 	dev_info(dev, "Link up, Gen%i\n", tmp & PCI_EXP_LNKSTA_CLS);
861 	return 0;
862 
863 err_reset_phy:
864 	dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
865 		dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0),
866 		dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1));
867 	imx6_pcie_reset_phy(imx6_pcie);
868 	return ret;
869 }
870 
871 static int imx6_pcie_host_init(struct pcie_port *pp)
872 {
873 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
874 	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
875 
876 	imx6_pcie_assert_core_reset(imx6_pcie);
877 	imx6_pcie_init_phy(imx6_pcie);
878 	imx6_pcie_deassert_core_reset(imx6_pcie);
879 	imx6_setup_phy_mpll(imx6_pcie);
880 
881 	return 0;
882 }
883 
884 static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
885 	.host_init = imx6_pcie_host_init,
886 };
887 
888 static const struct dw_pcie_ops dw_pcie_ops = {
889 	.start_link = imx6_pcie_start_link,
890 };
891 
892 #ifdef CONFIG_PM_SLEEP
893 static void imx6_pcie_ltssm_disable(struct device *dev)
894 {
895 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
896 
897 	switch (imx6_pcie->drvdata->variant) {
898 	case IMX6SX:
899 	case IMX6QP:
900 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
901 				   IMX6Q_GPR12_PCIE_CTL_2, 0);
902 		break;
903 	case IMX7D:
904 	case IMX8MM:
905 		reset_control_assert(imx6_pcie->apps_reset);
906 		break;
907 	default:
908 		dev_err(dev, "ltssm_disable not supported\n");
909 	}
910 }
911 
912 static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
913 {
914 	struct device *dev = imx6_pcie->pci->dev;
915 
916 	/* Some variants have a turnoff reset in DT */
917 	if (imx6_pcie->turnoff_reset) {
918 		reset_control_assert(imx6_pcie->turnoff_reset);
919 		reset_control_deassert(imx6_pcie->turnoff_reset);
920 		goto pm_turnoff_sleep;
921 	}
922 
923 	/* Others poke directly at IOMUXC registers */
924 	switch (imx6_pcie->drvdata->variant) {
925 	case IMX6SX:
926 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
927 				IMX6SX_GPR12_PCIE_PM_TURN_OFF,
928 				IMX6SX_GPR12_PCIE_PM_TURN_OFF);
929 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
930 				IMX6SX_GPR12_PCIE_PM_TURN_OFF, 0);
931 		break;
932 	default:
933 		dev_err(dev, "PME_Turn_Off not implemented\n");
934 		return;
935 	}
936 
937 	/*
938 	 * Components with an upstream port must respond to
939 	 * PME_Turn_Off with PME_TO_Ack but we can't check.
940 	 *
941 	 * The standard recommends a 1-10ms timeout after which to
942 	 * proceed anyway as if acks were received.
943 	 */
944 pm_turnoff_sleep:
945 	usleep_range(1000, 10000);
946 }
947 
948 static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
949 {
950 	clk_disable_unprepare(imx6_pcie->pcie);
951 	clk_disable_unprepare(imx6_pcie->pcie_phy);
952 	clk_disable_unprepare(imx6_pcie->pcie_bus);
953 
954 	switch (imx6_pcie->drvdata->variant) {
955 	case IMX6SX:
956 		clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
957 		break;
958 	case IMX7D:
959 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
960 				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
961 				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
962 		break;
963 	case IMX8MQ:
964 	case IMX8MM:
965 		clk_disable_unprepare(imx6_pcie->pcie_aux);
966 		break;
967 	default:
968 		break;
969 	}
970 }
971 
972 static int imx6_pcie_suspend_noirq(struct device *dev)
973 {
974 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
975 
976 	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
977 		return 0;
978 
979 	imx6_pcie_pm_turnoff(imx6_pcie);
980 	imx6_pcie_ltssm_disable(dev);
981 	imx6_pcie_clk_disable(imx6_pcie);
982 	switch (imx6_pcie->drvdata->variant) {
983 	case IMX8MM:
984 		if (phy_power_off(imx6_pcie->phy))
985 			dev_err(dev, "unable to power off PHY\n");
986 		break;
987 	default:
988 		break;
989 	}
990 
991 	return 0;
992 }
993 
994 static int imx6_pcie_resume_noirq(struct device *dev)
995 {
996 	int ret;
997 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
998 	struct pcie_port *pp = &imx6_pcie->pci->pp;
999 
1000 	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
1001 		return 0;
1002 
1003 	imx6_pcie_assert_core_reset(imx6_pcie);
1004 	imx6_pcie_init_phy(imx6_pcie);
1005 	imx6_pcie_deassert_core_reset(imx6_pcie);
1006 	dw_pcie_setup_rc(pp);
1007 
1008 	ret = imx6_pcie_start_link(imx6_pcie->pci);
1009 	if (ret < 0)
1010 		dev_info(dev, "pcie link is down after resume.\n");
1011 
1012 	return 0;
1013 }
1014 #endif
1015 
1016 static const struct dev_pm_ops imx6_pcie_pm_ops = {
1017 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq,
1018 				      imx6_pcie_resume_noirq)
1019 };
1020 
1021 static int imx6_pcie_probe(struct platform_device *pdev)
1022 {
1023 	struct device *dev = &pdev->dev;
1024 	struct dw_pcie *pci;
1025 	struct imx6_pcie *imx6_pcie;
1026 	struct device_node *np;
1027 	struct resource *dbi_base;
1028 	struct device_node *node = dev->of_node;
1029 	int ret;
1030 	u16 val;
1031 
1032 	imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
1033 	if (!imx6_pcie)
1034 		return -ENOMEM;
1035 
1036 	pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
1037 	if (!pci)
1038 		return -ENOMEM;
1039 
1040 	pci->dev = dev;
1041 	pci->ops = &dw_pcie_ops;
1042 	pci->pp.ops = &imx6_pcie_host_ops;
1043 
1044 	imx6_pcie->pci = pci;
1045 	imx6_pcie->drvdata = of_device_get_match_data(dev);
1046 
1047 	/* Find the PHY if one is defined, only imx7d uses it */
1048 	np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0);
1049 	if (np) {
1050 		struct resource res;
1051 
1052 		ret = of_address_to_resource(np, 0, &res);
1053 		if (ret) {
1054 			dev_err(dev, "Unable to map PCIe PHY\n");
1055 			return ret;
1056 		}
1057 		imx6_pcie->phy_base = devm_ioremap_resource(dev, &res);
1058 		if (IS_ERR(imx6_pcie->phy_base))
1059 			return PTR_ERR(imx6_pcie->phy_base);
1060 	}
1061 
1062 	dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1063 	pci->dbi_base = devm_ioremap_resource(dev, dbi_base);
1064 	if (IS_ERR(pci->dbi_base))
1065 		return PTR_ERR(pci->dbi_base);
1066 
1067 	/* Fetch GPIOs */
1068 	imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
1069 	imx6_pcie->gpio_active_high = of_property_read_bool(node,
1070 						"reset-gpio-active-high");
1071 	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
1072 		ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
1073 				imx6_pcie->gpio_active_high ?
1074 					GPIOF_OUT_INIT_HIGH :
1075 					GPIOF_OUT_INIT_LOW,
1076 				"PCIe reset");
1077 		if (ret) {
1078 			dev_err(dev, "unable to get reset gpio\n");
1079 			return ret;
1080 		}
1081 	} else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) {
1082 		return imx6_pcie->reset_gpio;
1083 	}
1084 
1085 	/* Fetch clocks */
1086 	imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus");
1087 	if (IS_ERR(imx6_pcie->pcie_bus))
1088 		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_bus),
1089 				     "pcie_bus clock source missing or invalid\n");
1090 
1091 	imx6_pcie->pcie = devm_clk_get(dev, "pcie");
1092 	if (IS_ERR(imx6_pcie->pcie))
1093 		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie),
1094 				     "pcie clock source missing or invalid\n");
1095 
1096 	switch (imx6_pcie->drvdata->variant) {
1097 	case IMX6SX:
1098 		imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
1099 							   "pcie_inbound_axi");
1100 		if (IS_ERR(imx6_pcie->pcie_inbound_axi))
1101 			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_inbound_axi),
1102 					     "pcie_inbound_axi clock missing or invalid\n");
1103 		break;
1104 	case IMX8MQ:
1105 		imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
1106 		if (IS_ERR(imx6_pcie->pcie_aux))
1107 			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
1108 					     "pcie_aux clock source missing or invalid\n");
1109 		fallthrough;
1110 	case IMX7D:
1111 		if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
1112 			imx6_pcie->controller_id = 1;
1113 
1114 		imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
1115 									    "pciephy");
1116 		if (IS_ERR(imx6_pcie->pciephy_reset)) {
1117 			dev_err(dev, "Failed to get PCIEPHY reset control\n");
1118 			return PTR_ERR(imx6_pcie->pciephy_reset);
1119 		}
1120 
1121 		imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
1122 									 "apps");
1123 		if (IS_ERR(imx6_pcie->apps_reset)) {
1124 			dev_err(dev, "Failed to get PCIE APPS reset control\n");
1125 			return PTR_ERR(imx6_pcie->apps_reset);
1126 		}
1127 		break;
1128 	case IMX8MM:
1129 		imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
1130 		if (IS_ERR(imx6_pcie->pcie_aux))
1131 			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
1132 					     "pcie_aux clock source missing or invalid\n");
1133 		imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
1134 									 "apps");
1135 		if (IS_ERR(imx6_pcie->apps_reset))
1136 			return dev_err_probe(dev, PTR_ERR(imx6_pcie->apps_reset),
1137 					     "failed to get pcie apps reset control\n");
1138 
1139 		imx6_pcie->phy = devm_phy_get(dev, "pcie-phy");
1140 		if (IS_ERR(imx6_pcie->phy))
1141 			return dev_err_probe(dev, PTR_ERR(imx6_pcie->phy),
1142 					     "failed to get pcie phy\n");
1143 
1144 		break;
1145 	default:
1146 		break;
1147 	}
1148 	/* Don't fetch the pcie_phy clock, if it has abstract PHY driver */
1149 	if (imx6_pcie->phy == NULL) {
1150 		imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy");
1151 		if (IS_ERR(imx6_pcie->pcie_phy))
1152 			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_phy),
1153 					     "pcie_phy clock source missing or invalid\n");
1154 	}
1155 
1156 
1157 	/* Grab turnoff reset */
1158 	imx6_pcie->turnoff_reset = devm_reset_control_get_optional_exclusive(dev, "turnoff");
1159 	if (IS_ERR(imx6_pcie->turnoff_reset)) {
1160 		dev_err(dev, "Failed to get TURNOFF reset control\n");
1161 		return PTR_ERR(imx6_pcie->turnoff_reset);
1162 	}
1163 
1164 	/* Grab GPR config register range */
1165 	imx6_pcie->iomuxc_gpr =
1166 		 syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
1167 	if (IS_ERR(imx6_pcie->iomuxc_gpr)) {
1168 		dev_err(dev, "unable to find iomuxc registers\n");
1169 		return PTR_ERR(imx6_pcie->iomuxc_gpr);
1170 	}
1171 
1172 	/* Grab PCIe PHY Tx Settings */
1173 	if (of_property_read_u32(node, "fsl,tx-deemph-gen1",
1174 				 &imx6_pcie->tx_deemph_gen1))
1175 		imx6_pcie->tx_deemph_gen1 = 0;
1176 
1177 	if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db",
1178 				 &imx6_pcie->tx_deemph_gen2_3p5db))
1179 		imx6_pcie->tx_deemph_gen2_3p5db = 0;
1180 
1181 	if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db",
1182 				 &imx6_pcie->tx_deemph_gen2_6db))
1183 		imx6_pcie->tx_deemph_gen2_6db = 20;
1184 
1185 	if (of_property_read_u32(node, "fsl,tx-swing-full",
1186 				 &imx6_pcie->tx_swing_full))
1187 		imx6_pcie->tx_swing_full = 127;
1188 
1189 	if (of_property_read_u32(node, "fsl,tx-swing-low",
1190 				 &imx6_pcie->tx_swing_low))
1191 		imx6_pcie->tx_swing_low = 127;
1192 
1193 	/* Limit link speed */
1194 	pci->link_gen = 1;
1195 	of_property_read_u32(node, "fsl,max-link-speed", &pci->link_gen);
1196 
1197 	imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie");
1198 	if (IS_ERR(imx6_pcie->vpcie)) {
1199 		if (PTR_ERR(imx6_pcie->vpcie) != -ENODEV)
1200 			return PTR_ERR(imx6_pcie->vpcie);
1201 		imx6_pcie->vpcie = NULL;
1202 	}
1203 
1204 	imx6_pcie->vph = devm_regulator_get_optional(&pdev->dev, "vph");
1205 	if (IS_ERR(imx6_pcie->vph)) {
1206 		if (PTR_ERR(imx6_pcie->vph) != -ENODEV)
1207 			return PTR_ERR(imx6_pcie->vph);
1208 		imx6_pcie->vph = NULL;
1209 	}
1210 
1211 	platform_set_drvdata(pdev, imx6_pcie);
1212 
1213 	ret = imx6_pcie_attach_pd(dev);
1214 	if (ret)
1215 		return ret;
1216 
1217 	ret = dw_pcie_host_init(&pci->pp);
1218 	if (ret < 0)
1219 		return ret;
1220 
1221 	if (pci_msi_enabled()) {
1222 		u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
1223 		val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
1224 		val |= PCI_MSI_FLAGS_ENABLE;
1225 		dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
1226 	}
1227 
1228 	return 0;
1229 }
1230 
1231 static void imx6_pcie_shutdown(struct platform_device *pdev)
1232 {
1233 	struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
1234 
1235 	/* bring down link, so bootloader gets clean state in case of reboot */
1236 	imx6_pcie_assert_core_reset(imx6_pcie);
1237 }
1238 
1239 static const struct imx6_pcie_drvdata drvdata[] = {
1240 	[IMX6Q] = {
1241 		.variant = IMX6Q,
1242 		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1243 			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1244 		.dbi_length = 0x200,
1245 	},
1246 	[IMX6SX] = {
1247 		.variant = IMX6SX,
1248 		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1249 			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
1250 			 IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1251 	},
1252 	[IMX6QP] = {
1253 		.variant = IMX6QP,
1254 		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1255 			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1256 		.dbi_length = 0x200,
1257 	},
1258 	[IMX7D] = {
1259 		.variant = IMX7D,
1260 		.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1261 	},
1262 	[IMX8MQ] = {
1263 		.variant = IMX8MQ,
1264 	},
1265 	[IMX8MM] = {
1266 		.variant = IMX8MM,
1267 		.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1268 	},
1269 };
1270 
1271 static const struct of_device_id imx6_pcie_of_match[] = {
1272 	{ .compatible = "fsl,imx6q-pcie",  .data = &drvdata[IMX6Q],  },
1273 	{ .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], },
1274 	{ .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], },
1275 	{ .compatible = "fsl,imx7d-pcie",  .data = &drvdata[IMX7D],  },
1276 	{ .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], },
1277 	{ .compatible = "fsl,imx8mm-pcie", .data = &drvdata[IMX8MM], },
1278 	{},
1279 };
1280 
1281 static struct platform_driver imx6_pcie_driver = {
1282 	.driver = {
1283 		.name	= "imx6q-pcie",
1284 		.of_match_table = imx6_pcie_of_match,
1285 		.suppress_bind_attrs = true,
1286 		.pm = &imx6_pcie_pm_ops,
1287 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1288 	},
1289 	.probe    = imx6_pcie_probe,
1290 	.shutdown = imx6_pcie_shutdown,
1291 };
1292 
1293 static void imx6_pcie_quirk(struct pci_dev *dev)
1294 {
1295 	struct pci_bus *bus = dev->bus;
1296 	struct pcie_port *pp = bus->sysdata;
1297 
1298 	/* Bus parent is the PCI bridge, its parent is this platform driver */
1299 	if (!bus->dev.parent || !bus->dev.parent->parent)
1300 		return;
1301 
1302 	/* Make sure we only quirk devices associated with this driver */
1303 	if (bus->dev.parent->parent->driver != &imx6_pcie_driver.driver)
1304 		return;
1305 
1306 	if (pci_is_root_bus(bus)) {
1307 		struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1308 		struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
1309 
1310 		/*
1311 		 * Limit config length to avoid the kernel reading beyond
1312 		 * the register set and causing an abort on i.MX 6Quad
1313 		 */
1314 		if (imx6_pcie->drvdata->dbi_length) {
1315 			dev->cfg_size = imx6_pcie->drvdata->dbi_length;
1316 			dev_info(&dev->dev, "Limiting cfg_size to %d\n",
1317 					dev->cfg_size);
1318 		}
1319 	}
1320 }
1321 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_SYNOPSYS, 0xabcd,
1322 			PCI_CLASS_BRIDGE_PCI, 8, imx6_pcie_quirk);
1323 
1324 static int __init imx6_pcie_init(void)
1325 {
1326 #ifdef CONFIG_ARM
1327 	/*
1328 	 * Since probe() can be deferred we need to make sure that
1329 	 * hook_fault_code is not called after __init memory is freed
1330 	 * by kernel and since imx6q_pcie_abort_handler() is a no-op,
1331 	 * we can install the handler here without risking it
1332 	 * accessing some uninitialized driver state.
1333 	 */
1334 	hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0,
1335 			"external abort on non-linefetch");
1336 #endif
1337 
1338 	return platform_driver_register(&imx6_pcie_driver);
1339 }
1340 device_initcall(imx6_pcie_init);
1341