xref: /linux/drivers/pci/controller/dwc/pci-imx6.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
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 
45 enum 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 
57 struct imx6_pcie_drvdata {
58 	enum imx6_pcie_variants variant;
59 	u32 flags;
60 	int dbi_length;
61 };
62 
63 struct 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 
144 static 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 
165 static 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) */
188 static 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 
214 static 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 
269 static 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 */
291 static 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 
325 static 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 
365 static 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 
406 static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
407 {
408 	WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ);
409 	return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14;
410 }
411 
412 static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
413 {
414 	struct dw_pcie *pci = imx6_pcie->pci;
415 	struct device *dev = pci->dev;
416 	unsigned int offset;
417 	int ret = 0;
418 
419 	switch (imx6_pcie->drvdata->variant) {
420 	case IMX6SX:
421 		ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
422 		if (ret) {
423 			dev_err(dev, "unable to enable pcie_axi clock\n");
424 			break;
425 		}
426 
427 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
428 				   IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
429 		break;
430 	case IMX6QP:
431 	case IMX6Q:
432 		/* power up core phy and enable ref clock */
433 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
434 				   IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
435 		/*
436 		 * the async reset input need ref clock to sync internally,
437 		 * when the ref clock comes after reset, internal synced
438 		 * reset time is too short, cannot meet the requirement.
439 		 * add one ~10us delay here.
440 		 */
441 		usleep_range(10, 100);
442 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
443 				   IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
444 		break;
445 	case IMX7D:
446 		break;
447 	case IMX8MQ:
448 		ret = clk_prepare_enable(imx6_pcie->pcie_aux);
449 		if (ret) {
450 			dev_err(dev, "unable to enable pcie_aux clock\n");
451 			break;
452 		}
453 
454 		offset = imx6_pcie_grp_offset(imx6_pcie);
455 		/*
456 		 * Set the over ride low and enabled
457 		 * make sure that REF_CLK is turned on.
458 		 */
459 		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
460 				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE,
461 				   0);
462 		regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
463 				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
464 				   IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
465 		break;
466 	}
467 
468 	return ret;
469 }
470 
471 static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)
472 {
473 	u32 val;
474 	struct device *dev = imx6_pcie->pci->dev;
475 
476 	if (regmap_read_poll_timeout(imx6_pcie->iomuxc_gpr,
477 				     IOMUXC_GPR22, val,
478 				     val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED,
479 				     PHY_PLL_LOCK_WAIT_USLEEP_MAX,
480 				     PHY_PLL_LOCK_WAIT_TIMEOUT))
481 		dev_err(dev, "PCIe PLL lock timeout\n");
482 }
483 
484 static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
485 {
486 	struct dw_pcie *pci = imx6_pcie->pci;
487 	struct device *dev = pci->dev;
488 	int ret;
489 
490 	if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) {
491 		ret = regulator_enable(imx6_pcie->vpcie);
492 		if (ret) {
493 			dev_err(dev, "failed to enable vpcie regulator: %d\n",
494 				ret);
495 			return;
496 		}
497 	}
498 
499 	ret = clk_prepare_enable(imx6_pcie->pcie_phy);
500 	if (ret) {
501 		dev_err(dev, "unable to enable pcie_phy clock\n");
502 		goto err_pcie_phy;
503 	}
504 
505 	ret = clk_prepare_enable(imx6_pcie->pcie_bus);
506 	if (ret) {
507 		dev_err(dev, "unable to enable pcie_bus clock\n");
508 		goto err_pcie_bus;
509 	}
510 
511 	ret = clk_prepare_enable(imx6_pcie->pcie);
512 	if (ret) {
513 		dev_err(dev, "unable to enable pcie clock\n");
514 		goto err_pcie;
515 	}
516 
517 	ret = imx6_pcie_enable_ref_clk(imx6_pcie);
518 	if (ret) {
519 		dev_err(dev, "unable to enable pcie ref clock\n");
520 		goto err_ref_clk;
521 	}
522 
523 	/* allow the clocks to stabilize */
524 	usleep_range(200, 500);
525 
526 	/* Some boards don't have PCIe reset GPIO. */
527 	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
528 		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
529 					imx6_pcie->gpio_active_high);
530 		msleep(100);
531 		gpio_set_value_cansleep(imx6_pcie->reset_gpio,
532 					!imx6_pcie->gpio_active_high);
533 	}
534 
535 	switch (imx6_pcie->drvdata->variant) {
536 	case IMX8MQ:
537 		reset_control_deassert(imx6_pcie->pciephy_reset);
538 		break;
539 	case IMX7D:
540 		reset_control_deassert(imx6_pcie->pciephy_reset);
541 
542 		/* Workaround for ERR010728, failure of PCI-e PLL VCO to
543 		 * oscillate, especially when cold.  This turns off "Duty-cycle
544 		 * Corrector" and other mysterious undocumented things.
545 		 */
546 		if (likely(imx6_pcie->phy_base)) {
547 			/* De-assert DCC_FB_EN */
548 			writel(PCIE_PHY_CMN_REG4_DCC_FB_EN,
549 			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG4);
550 			/* Assert RX_EQS and RX_EQS_SEL */
551 			writel(PCIE_PHY_CMN_REG24_RX_EQ_SEL
552 				| PCIE_PHY_CMN_REG24_RX_EQ,
553 			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG24);
554 			/* Assert ATT_MODE */
555 			writel(PCIE_PHY_CMN_REG26_ATT_MODE,
556 			       imx6_pcie->phy_base + PCIE_PHY_CMN_REG26);
557 		} else {
558 			dev_warn(dev, "Unable to apply ERR010728 workaround. DT missing fsl,imx7d-pcie-phy phandle ?\n");
559 		}
560 
561 		imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
562 		break;
563 	case IMX6SX:
564 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
565 				   IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
566 		break;
567 	case IMX6QP:
568 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
569 				   IMX6Q_GPR1_PCIE_SW_RST, 0);
570 
571 		usleep_range(200, 500);
572 		break;
573 	case IMX6Q:		/* Nothing to do */
574 		break;
575 	}
576 
577 	return;
578 
579 err_ref_clk:
580 	clk_disable_unprepare(imx6_pcie->pcie);
581 err_pcie:
582 	clk_disable_unprepare(imx6_pcie->pcie_bus);
583 err_pcie_bus:
584 	clk_disable_unprepare(imx6_pcie->pcie_phy);
585 err_pcie_phy:
586 	if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
587 		ret = regulator_disable(imx6_pcie->vpcie);
588 		if (ret)
589 			dev_err(dev, "failed to disable vpcie regulator: %d\n",
590 				ret);
591 	}
592 }
593 
594 static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie)
595 {
596 	unsigned int mask, val;
597 
598 	if (imx6_pcie->drvdata->variant == IMX8MQ &&
599 	    imx6_pcie->controller_id == 1) {
600 		mask   = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE;
601 		val    = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
602 				    PCI_EXP_TYPE_ROOT_PORT);
603 	} else {
604 		mask = IMX6Q_GPR12_DEVICE_TYPE;
605 		val  = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE,
606 				  PCI_EXP_TYPE_ROOT_PORT);
607 	}
608 
609 	regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val);
610 }
611 
612 static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
613 {
614 	switch (imx6_pcie->drvdata->variant) {
615 	case IMX8MQ:
616 		/*
617 		 * TODO: Currently this code assumes external
618 		 * oscillator is being used
619 		 */
620 		regmap_update_bits(imx6_pcie->iomuxc_gpr,
621 				   imx6_pcie_grp_offset(imx6_pcie),
622 				   IMX8MQ_GPR_PCIE_REF_USE_PAD,
623 				   IMX8MQ_GPR_PCIE_REF_USE_PAD);
624 		break;
625 	case IMX7D:
626 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
627 				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
628 		break;
629 	case IMX6SX:
630 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
631 				   IMX6SX_GPR12_PCIE_RX_EQ_MASK,
632 				   IMX6SX_GPR12_PCIE_RX_EQ_2);
633 		fallthrough;
634 	default:
635 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
636 				   IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
637 
638 		/* configure constant input signal to the pcie ctrl and phy */
639 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
640 				   IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
641 
642 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
643 				   IMX6Q_GPR8_TX_DEEMPH_GEN1,
644 				   imx6_pcie->tx_deemph_gen1 << 0);
645 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
646 				   IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
647 				   imx6_pcie->tx_deemph_gen2_3p5db << 6);
648 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
649 				   IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
650 				   imx6_pcie->tx_deemph_gen2_6db << 12);
651 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
652 				   IMX6Q_GPR8_TX_SWING_FULL,
653 				   imx6_pcie->tx_swing_full << 18);
654 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
655 				   IMX6Q_GPR8_TX_SWING_LOW,
656 				   imx6_pcie->tx_swing_low << 25);
657 		break;
658 	}
659 
660 	imx6_pcie_configure_type(imx6_pcie);
661 }
662 
663 static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
664 {
665 	unsigned long phy_rate = clk_get_rate(imx6_pcie->pcie_phy);
666 	int mult, div;
667 	u16 val;
668 
669 	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
670 		return 0;
671 
672 	switch (phy_rate) {
673 	case 125000000:
674 		/*
675 		 * The default settings of the MPLL are for a 125MHz input
676 		 * clock, so no need to reconfigure anything in that case.
677 		 */
678 		return 0;
679 	case 100000000:
680 		mult = 25;
681 		div = 0;
682 		break;
683 	case 200000000:
684 		mult = 25;
685 		div = 1;
686 		break;
687 	default:
688 		dev_err(imx6_pcie->pci->dev,
689 			"Unsupported PHY reference clock rate %lu\n", phy_rate);
690 		return -EINVAL;
691 	}
692 
693 	pcie_phy_read(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, &val);
694 	val &= ~(PCIE_PHY_MPLL_MULTIPLIER_MASK <<
695 		 PCIE_PHY_MPLL_MULTIPLIER_SHIFT);
696 	val |= mult << PCIE_PHY_MPLL_MULTIPLIER_SHIFT;
697 	val |= PCIE_PHY_MPLL_MULTIPLIER_OVRD;
698 	pcie_phy_write(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, val);
699 
700 	pcie_phy_read(imx6_pcie, PCIE_PHY_ATEOVRD, &val);
701 	val &= ~(PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK <<
702 		 PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT);
703 	val |= div << PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT;
704 	val |= PCIE_PHY_ATEOVRD_EN;
705 	pcie_phy_write(imx6_pcie, PCIE_PHY_ATEOVRD, val);
706 
707 	return 0;
708 }
709 
710 static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie)
711 {
712 	struct dw_pcie *pci = imx6_pcie->pci;
713 	struct device *dev = pci->dev;
714 	u32 tmp;
715 	unsigned int retries;
716 
717 	for (retries = 0; retries < 200; retries++) {
718 		tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
719 		/* Test if the speed change finished. */
720 		if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
721 			return 0;
722 		usleep_range(100, 1000);
723 	}
724 
725 	dev_err(dev, "Speed change timeout\n");
726 	return -ETIMEDOUT;
727 }
728 
729 static void imx6_pcie_ltssm_enable(struct device *dev)
730 {
731 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
732 
733 	switch (imx6_pcie->drvdata->variant) {
734 	case IMX6Q:
735 	case IMX6SX:
736 	case IMX6QP:
737 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
738 				   IMX6Q_GPR12_PCIE_CTL_2,
739 				   IMX6Q_GPR12_PCIE_CTL_2);
740 		break;
741 	case IMX7D:
742 	case IMX8MQ:
743 		reset_control_deassert(imx6_pcie->apps_reset);
744 		break;
745 	}
746 }
747 
748 static int imx6_pcie_start_link(struct dw_pcie *pci)
749 {
750 	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
751 	struct device *dev = pci->dev;
752 	u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
753 	u32 tmp;
754 	int ret;
755 
756 	/*
757 	 * Force Gen1 operation when starting the link.  In case the link is
758 	 * started in Gen2 mode, there is a possibility the devices on the
759 	 * bus will not be detected at all.  This happens with PCIe switches.
760 	 */
761 	tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
762 	tmp &= ~PCI_EXP_LNKCAP_SLS;
763 	tmp |= PCI_EXP_LNKCAP_SLS_2_5GB;
764 	dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
765 
766 	/* Start LTSSM. */
767 	imx6_pcie_ltssm_enable(dev);
768 
769 	ret = dw_pcie_wait_for_link(pci);
770 	if (ret)
771 		goto err_reset_phy;
772 
773 	if (pci->link_gen == 2) {
774 		/* Allow Gen2 mode after the link is up. */
775 		tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
776 		tmp &= ~PCI_EXP_LNKCAP_SLS;
777 		tmp |= PCI_EXP_LNKCAP_SLS_5_0GB;
778 		dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
779 
780 		/*
781 		 * Start Directed Speed Change so the best possible
782 		 * speed both link partners support can be negotiated.
783 		 */
784 		tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
785 		tmp |= PORT_LOGIC_SPEED_CHANGE;
786 		dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
787 
788 		if (imx6_pcie->drvdata->flags &
789 		    IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE) {
790 			/*
791 			 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
792 			 * from i.MX6 family when no link speed transition
793 			 * occurs and we go Gen1 -> yep, Gen1. The difference
794 			 * is that, in such case, it will not be cleared by HW
795 			 * which will cause the following code to report false
796 			 * failure.
797 			 */
798 
799 			ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
800 			if (ret) {
801 				dev_err(dev, "Failed to bring link up!\n");
802 				goto err_reset_phy;
803 			}
804 		}
805 
806 		/* Make sure link training is finished as well! */
807 		ret = dw_pcie_wait_for_link(pci);
808 		if (ret) {
809 			dev_err(dev, "Failed to bring link up!\n");
810 			goto err_reset_phy;
811 		}
812 	} else {
813 		dev_info(dev, "Link: Gen2 disabled\n");
814 	}
815 
816 	tmp = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA);
817 	dev_info(dev, "Link up, Gen%i\n", tmp & PCI_EXP_LNKSTA_CLS);
818 	return 0;
819 
820 err_reset_phy:
821 	dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
822 		dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0),
823 		dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1));
824 	imx6_pcie_reset_phy(imx6_pcie);
825 	return ret;
826 }
827 
828 static int imx6_pcie_host_init(struct pcie_port *pp)
829 {
830 	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
831 	struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
832 
833 	imx6_pcie_assert_core_reset(imx6_pcie);
834 	imx6_pcie_init_phy(imx6_pcie);
835 	imx6_pcie_deassert_core_reset(imx6_pcie);
836 	imx6_setup_phy_mpll(imx6_pcie);
837 
838 	return 0;
839 }
840 
841 static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
842 	.host_init = imx6_pcie_host_init,
843 };
844 
845 static const struct dw_pcie_ops dw_pcie_ops = {
846 	.start_link = imx6_pcie_start_link,
847 };
848 
849 #ifdef CONFIG_PM_SLEEP
850 static void imx6_pcie_ltssm_disable(struct device *dev)
851 {
852 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
853 
854 	switch (imx6_pcie->drvdata->variant) {
855 	case IMX6SX:
856 	case IMX6QP:
857 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
858 				   IMX6Q_GPR12_PCIE_CTL_2, 0);
859 		break;
860 	case IMX7D:
861 		reset_control_assert(imx6_pcie->apps_reset);
862 		break;
863 	default:
864 		dev_err(dev, "ltssm_disable not supported\n");
865 	}
866 }
867 
868 static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
869 {
870 	struct device *dev = imx6_pcie->pci->dev;
871 
872 	/* Some variants have a turnoff reset in DT */
873 	if (imx6_pcie->turnoff_reset) {
874 		reset_control_assert(imx6_pcie->turnoff_reset);
875 		reset_control_deassert(imx6_pcie->turnoff_reset);
876 		goto pm_turnoff_sleep;
877 	}
878 
879 	/* Others poke directly at IOMUXC registers */
880 	switch (imx6_pcie->drvdata->variant) {
881 	case IMX6SX:
882 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
883 				IMX6SX_GPR12_PCIE_PM_TURN_OFF,
884 				IMX6SX_GPR12_PCIE_PM_TURN_OFF);
885 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
886 				IMX6SX_GPR12_PCIE_PM_TURN_OFF, 0);
887 		break;
888 	default:
889 		dev_err(dev, "PME_Turn_Off not implemented\n");
890 		return;
891 	}
892 
893 	/*
894 	 * Components with an upstream port must respond to
895 	 * PME_Turn_Off with PME_TO_Ack but we can't check.
896 	 *
897 	 * The standard recommends a 1-10ms timeout after which to
898 	 * proceed anyway as if acks were received.
899 	 */
900 pm_turnoff_sleep:
901 	usleep_range(1000, 10000);
902 }
903 
904 static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
905 {
906 	clk_disable_unprepare(imx6_pcie->pcie);
907 	clk_disable_unprepare(imx6_pcie->pcie_phy);
908 	clk_disable_unprepare(imx6_pcie->pcie_bus);
909 
910 	switch (imx6_pcie->drvdata->variant) {
911 	case IMX6SX:
912 		clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
913 		break;
914 	case IMX7D:
915 		regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
916 				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
917 				   IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
918 		break;
919 	case IMX8MQ:
920 		clk_disable_unprepare(imx6_pcie->pcie_aux);
921 		break;
922 	default:
923 		break;
924 	}
925 }
926 
927 static int imx6_pcie_suspend_noirq(struct device *dev)
928 {
929 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
930 
931 	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
932 		return 0;
933 
934 	imx6_pcie_pm_turnoff(imx6_pcie);
935 	imx6_pcie_clk_disable(imx6_pcie);
936 	imx6_pcie_ltssm_disable(dev);
937 
938 	return 0;
939 }
940 
941 static int imx6_pcie_resume_noirq(struct device *dev)
942 {
943 	int ret;
944 	struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
945 	struct pcie_port *pp = &imx6_pcie->pci->pp;
946 
947 	if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
948 		return 0;
949 
950 	imx6_pcie_assert_core_reset(imx6_pcie);
951 	imx6_pcie_init_phy(imx6_pcie);
952 	imx6_pcie_deassert_core_reset(imx6_pcie);
953 	dw_pcie_setup_rc(pp);
954 
955 	ret = imx6_pcie_start_link(imx6_pcie->pci);
956 	if (ret < 0)
957 		dev_info(dev, "pcie link is down after resume.\n");
958 
959 	return 0;
960 }
961 #endif
962 
963 static const struct dev_pm_ops imx6_pcie_pm_ops = {
964 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq,
965 				      imx6_pcie_resume_noirq)
966 };
967 
968 static int imx6_pcie_probe(struct platform_device *pdev)
969 {
970 	struct device *dev = &pdev->dev;
971 	struct dw_pcie *pci;
972 	struct imx6_pcie *imx6_pcie;
973 	struct device_node *np;
974 	struct resource *dbi_base;
975 	struct device_node *node = dev->of_node;
976 	int ret;
977 	u16 val;
978 
979 	imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
980 	if (!imx6_pcie)
981 		return -ENOMEM;
982 
983 	pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
984 	if (!pci)
985 		return -ENOMEM;
986 
987 	pci->dev = dev;
988 	pci->ops = &dw_pcie_ops;
989 	pci->pp.ops = &imx6_pcie_host_ops;
990 
991 	imx6_pcie->pci = pci;
992 	imx6_pcie->drvdata = of_device_get_match_data(dev);
993 
994 	/* Find the PHY if one is defined, only imx7d uses it */
995 	np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0);
996 	if (np) {
997 		struct resource res;
998 
999 		ret = of_address_to_resource(np, 0, &res);
1000 		if (ret) {
1001 			dev_err(dev, "Unable to map PCIe PHY\n");
1002 			return ret;
1003 		}
1004 		imx6_pcie->phy_base = devm_ioremap_resource(dev, &res);
1005 		if (IS_ERR(imx6_pcie->phy_base)) {
1006 			dev_err(dev, "Unable to map PCIe PHY\n");
1007 			return PTR_ERR(imx6_pcie->phy_base);
1008 		}
1009 	}
1010 
1011 	dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1012 	pci->dbi_base = devm_ioremap_resource(dev, dbi_base);
1013 	if (IS_ERR(pci->dbi_base))
1014 		return PTR_ERR(pci->dbi_base);
1015 
1016 	/* Fetch GPIOs */
1017 	imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
1018 	imx6_pcie->gpio_active_high = of_property_read_bool(node,
1019 						"reset-gpio-active-high");
1020 	if (gpio_is_valid(imx6_pcie->reset_gpio)) {
1021 		ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
1022 				imx6_pcie->gpio_active_high ?
1023 					GPIOF_OUT_INIT_HIGH :
1024 					GPIOF_OUT_INIT_LOW,
1025 				"PCIe reset");
1026 		if (ret) {
1027 			dev_err(dev, "unable to get reset gpio\n");
1028 			return ret;
1029 		}
1030 	} else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) {
1031 		return imx6_pcie->reset_gpio;
1032 	}
1033 
1034 	/* Fetch clocks */
1035 	imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy");
1036 	if (IS_ERR(imx6_pcie->pcie_phy))
1037 		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_phy),
1038 				     "pcie_phy clock source missing or invalid\n");
1039 
1040 	imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus");
1041 	if (IS_ERR(imx6_pcie->pcie_bus))
1042 		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_bus),
1043 				     "pcie_bus clock source missing or invalid\n");
1044 
1045 	imx6_pcie->pcie = devm_clk_get(dev, "pcie");
1046 	if (IS_ERR(imx6_pcie->pcie))
1047 		return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie),
1048 				     "pcie clock source missing or invalid\n");
1049 
1050 	switch (imx6_pcie->drvdata->variant) {
1051 	case IMX6SX:
1052 		imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
1053 							   "pcie_inbound_axi");
1054 		if (IS_ERR(imx6_pcie->pcie_inbound_axi))
1055 			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_inbound_axi),
1056 					     "pcie_inbound_axi clock missing or invalid\n");
1057 		break;
1058 	case IMX8MQ:
1059 		imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
1060 		if (IS_ERR(imx6_pcie->pcie_aux))
1061 			return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
1062 					     "pcie_aux clock source missing or invalid\n");
1063 		fallthrough;
1064 	case IMX7D:
1065 		if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
1066 			imx6_pcie->controller_id = 1;
1067 
1068 		imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
1069 									    "pciephy");
1070 		if (IS_ERR(imx6_pcie->pciephy_reset)) {
1071 			dev_err(dev, "Failed to get PCIEPHY reset control\n");
1072 			return PTR_ERR(imx6_pcie->pciephy_reset);
1073 		}
1074 
1075 		imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
1076 									 "apps");
1077 		if (IS_ERR(imx6_pcie->apps_reset)) {
1078 			dev_err(dev, "Failed to get PCIE APPS reset control\n");
1079 			return PTR_ERR(imx6_pcie->apps_reset);
1080 		}
1081 		break;
1082 	default:
1083 		break;
1084 	}
1085 
1086 	/* Grab turnoff reset */
1087 	imx6_pcie->turnoff_reset = devm_reset_control_get_optional_exclusive(dev, "turnoff");
1088 	if (IS_ERR(imx6_pcie->turnoff_reset)) {
1089 		dev_err(dev, "Failed to get TURNOFF reset control\n");
1090 		return PTR_ERR(imx6_pcie->turnoff_reset);
1091 	}
1092 
1093 	/* Grab GPR config register range */
1094 	imx6_pcie->iomuxc_gpr =
1095 		 syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
1096 	if (IS_ERR(imx6_pcie->iomuxc_gpr)) {
1097 		dev_err(dev, "unable to find iomuxc registers\n");
1098 		return PTR_ERR(imx6_pcie->iomuxc_gpr);
1099 	}
1100 
1101 	/* Grab PCIe PHY Tx Settings */
1102 	if (of_property_read_u32(node, "fsl,tx-deemph-gen1",
1103 				 &imx6_pcie->tx_deemph_gen1))
1104 		imx6_pcie->tx_deemph_gen1 = 0;
1105 
1106 	if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db",
1107 				 &imx6_pcie->tx_deemph_gen2_3p5db))
1108 		imx6_pcie->tx_deemph_gen2_3p5db = 0;
1109 
1110 	if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db",
1111 				 &imx6_pcie->tx_deemph_gen2_6db))
1112 		imx6_pcie->tx_deemph_gen2_6db = 20;
1113 
1114 	if (of_property_read_u32(node, "fsl,tx-swing-full",
1115 				 &imx6_pcie->tx_swing_full))
1116 		imx6_pcie->tx_swing_full = 127;
1117 
1118 	if (of_property_read_u32(node, "fsl,tx-swing-low",
1119 				 &imx6_pcie->tx_swing_low))
1120 		imx6_pcie->tx_swing_low = 127;
1121 
1122 	/* Limit link speed */
1123 	pci->link_gen = 1;
1124 	ret = of_property_read_u32(node, "fsl,max-link-speed", &pci->link_gen);
1125 
1126 	imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie");
1127 	if (IS_ERR(imx6_pcie->vpcie)) {
1128 		if (PTR_ERR(imx6_pcie->vpcie) != -ENODEV)
1129 			return PTR_ERR(imx6_pcie->vpcie);
1130 		imx6_pcie->vpcie = NULL;
1131 	}
1132 
1133 	platform_set_drvdata(pdev, imx6_pcie);
1134 
1135 	ret = imx6_pcie_attach_pd(dev);
1136 	if (ret)
1137 		return ret;
1138 
1139 	ret = dw_pcie_host_init(&pci->pp);
1140 	if (ret < 0)
1141 		return ret;
1142 
1143 	if (pci_msi_enabled()) {
1144 		u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
1145 		val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
1146 		val |= PCI_MSI_FLAGS_ENABLE;
1147 		dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
1148 	}
1149 
1150 	return 0;
1151 }
1152 
1153 static void imx6_pcie_shutdown(struct platform_device *pdev)
1154 {
1155 	struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
1156 
1157 	/* bring down link, so bootloader gets clean state in case of reboot */
1158 	imx6_pcie_assert_core_reset(imx6_pcie);
1159 }
1160 
1161 static const struct imx6_pcie_drvdata drvdata[] = {
1162 	[IMX6Q] = {
1163 		.variant = IMX6Q,
1164 		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1165 			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1166 		.dbi_length = 0x200,
1167 	},
1168 	[IMX6SX] = {
1169 		.variant = IMX6SX,
1170 		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1171 			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
1172 			 IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1173 	},
1174 	[IMX6QP] = {
1175 		.variant = IMX6QP,
1176 		.flags = IMX6_PCIE_FLAG_IMX6_PHY |
1177 			 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1178 	},
1179 	[IMX7D] = {
1180 		.variant = IMX7D,
1181 		.flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1182 	},
1183 	[IMX8MQ] = {
1184 		.variant = IMX8MQ,
1185 	},
1186 };
1187 
1188 static const struct of_device_id imx6_pcie_of_match[] = {
1189 	{ .compatible = "fsl,imx6q-pcie",  .data = &drvdata[IMX6Q],  },
1190 	{ .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], },
1191 	{ .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], },
1192 	{ .compatible = "fsl,imx7d-pcie",  .data = &drvdata[IMX7D],  },
1193 	{ .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], } ,
1194 	{},
1195 };
1196 
1197 static struct platform_driver imx6_pcie_driver = {
1198 	.driver = {
1199 		.name	= "imx6q-pcie",
1200 		.of_match_table = imx6_pcie_of_match,
1201 		.suppress_bind_attrs = true,
1202 		.pm = &imx6_pcie_pm_ops,
1203 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1204 	},
1205 	.probe    = imx6_pcie_probe,
1206 	.shutdown = imx6_pcie_shutdown,
1207 };
1208 
1209 static void imx6_pcie_quirk(struct pci_dev *dev)
1210 {
1211 	struct pci_bus *bus = dev->bus;
1212 	struct pcie_port *pp = bus->sysdata;
1213 
1214 	/* Bus parent is the PCI bridge, its parent is this platform driver */
1215 	if (!bus->dev.parent || !bus->dev.parent->parent)
1216 		return;
1217 
1218 	/* Make sure we only quirk devices associated with this driver */
1219 	if (bus->dev.parent->parent->driver != &imx6_pcie_driver.driver)
1220 		return;
1221 
1222 	if (pci_is_root_bus(bus)) {
1223 		struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1224 		struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
1225 
1226 		/*
1227 		 * Limit config length to avoid the kernel reading beyond
1228 		 * the register set and causing an abort on i.MX 6Quad
1229 		 */
1230 		if (imx6_pcie->drvdata->dbi_length) {
1231 			dev->cfg_size = imx6_pcie->drvdata->dbi_length;
1232 			dev_info(&dev->dev, "Limiting cfg_size to %d\n",
1233 					dev->cfg_size);
1234 		}
1235 	}
1236 }
1237 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_SYNOPSYS, 0xabcd,
1238 			PCI_CLASS_BRIDGE_PCI, 8, imx6_pcie_quirk);
1239 
1240 static int __init imx6_pcie_init(void)
1241 {
1242 #ifdef CONFIG_ARM
1243 	/*
1244 	 * Since probe() can be deferred we need to make sure that
1245 	 * hook_fault_code is not called after __init memory is freed
1246 	 * by kernel and since imx6q_pcie_abort_handler() is a no-op,
1247 	 * we can install the handler here without risking it
1248 	 * accessing some uninitialized driver state.
1249 	 */
1250 	hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0,
1251 			"external abort on non-linefetch");
1252 #endif
1253 
1254 	return platform_driver_register(&imx6_pcie_driver);
1255 }
1256 device_initcall(imx6_pcie_init);
1257