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  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * pci-j721e - PCIe controller driver for TI's J721E SoCs
  4 *
  5 * Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com
  6 * Author: Kishon Vijay Abraham I <kishon@ti.com>
  7 */
  8
  9#include <linux/clk.h>
 10#include <linux/clk-provider.h>
 11#include <linux/container_of.h>
 12#include <linux/delay.h>
 13#include <linux/gpio/consumer.h>
 14#include <linux/io.h>
 15#include <linux/irqchip/chained_irq.h>
 16#include <linux/irqdomain.h>
 17#include <linux/mfd/syscon.h>
 18#include <linux/of.h>
 19#include <linux/pci.h>
 20#include <linux/platform_device.h>
 21#include <linux/pm_runtime.h>
 22#include <linux/regmap.h>
 23
 24#include "../../pci.h"
 25#include "pcie-cadence.h"
 26
 27#define cdns_pcie_to_rc(p) container_of(p, struct cdns_pcie_rc, pcie)
 28
 29#define ENABLE_REG_SYS_2	0x108
 30#define STATUS_REG_SYS_2	0x508
 31#define STATUS_CLR_REG_SYS_2	0x708
 32#define LINK_DOWN		BIT(1)
 33#define J7200_LINK_DOWN		BIT(10)
 34
 35#define J721E_PCIE_USER_CMD_STATUS	0x4
 36#define LINK_TRAINING_ENABLE		BIT(0)
 37
 38#define J721E_PCIE_USER_LINKSTATUS	0x14
 39#define LINK_STATUS			GENMASK(1, 0)
 40
 41enum link_status {
 42	NO_RECEIVERS_DETECTED,
 43	LINK_TRAINING_IN_PROGRESS,
 44	LINK_UP_DL_IN_PROGRESS,
 45	LINK_UP_DL_COMPLETED,
 46};
 47
 48#define J721E_MODE_RC			BIT(7)
 49#define LANE_COUNT(n)			((n) << 8)
 50
 51#define ACSPCIE_PAD_DISABLE_MASK	GENMASK(1, 0)
 52#define GENERATION_SEL_MASK		GENMASK(1, 0)
 53
 54struct j721e_pcie {
 55	struct cdns_pcie	*cdns_pcie;
 56	struct clk		*refclk;
 57	u32			mode;
 58	u32			num_lanes;
 59	u32			max_lanes;
 60	struct gpio_desc	*reset_gpio;
 61	void __iomem		*user_cfg_base;
 62	void __iomem		*intd_cfg_base;
 63	u32			linkdown_irq_regfield;
 64};
 65
 66enum j721e_pcie_mode {
 67	PCI_MODE_RC,
 68	PCI_MODE_EP,
 69};
 70
 71struct j721e_pcie_data {
 72	enum j721e_pcie_mode	mode;
 73	unsigned int		quirk_retrain_flag:1;
 74	unsigned int		quirk_detect_quiet_flag:1;
 75	unsigned int		quirk_disable_flr:1;
 76	u32			linkdown_irq_regfield;
 77	unsigned int		byte_access_allowed:1;
 78	unsigned int		max_lanes;
 79};
 80
 81static inline u32 j721e_pcie_user_readl(struct j721e_pcie *pcie, u32 offset)
 82{
 83	return readl(pcie->user_cfg_base + offset);
 84}
 85
 86static inline void j721e_pcie_user_writel(struct j721e_pcie *pcie, u32 offset,
 87					  u32 value)
 88{
 89	writel(value, pcie->user_cfg_base + offset);
 90}
 91
 92static inline u32 j721e_pcie_intd_readl(struct j721e_pcie *pcie, u32 offset)
 93{
 94	return readl(pcie->intd_cfg_base + offset);
 95}
 96
 97static inline void j721e_pcie_intd_writel(struct j721e_pcie *pcie, u32 offset,
 98					  u32 value)
 99{
100	writel(value, pcie->intd_cfg_base + offset);
101}
102
103static irqreturn_t j721e_pcie_link_irq_handler(int irq, void *priv)
104{
105	struct j721e_pcie *pcie = priv;
106	struct device *dev = pcie->cdns_pcie->dev;
107	u32 reg;
108
109	reg = j721e_pcie_intd_readl(pcie, STATUS_REG_SYS_2);
110	if (!(reg & pcie->linkdown_irq_regfield))
111		return IRQ_NONE;
112
113	dev_err(dev, "LINK DOWN!\n");
114
115	j721e_pcie_intd_writel(pcie, STATUS_CLR_REG_SYS_2, pcie->linkdown_irq_regfield);
116	return IRQ_HANDLED;
117}
118
119static void j721e_pcie_config_link_irq(struct j721e_pcie *pcie)
120{
121	u32 reg;
122
123	reg = j721e_pcie_intd_readl(pcie, ENABLE_REG_SYS_2);
124	reg |= pcie->linkdown_irq_regfield;
125	j721e_pcie_intd_writel(pcie, ENABLE_REG_SYS_2, reg);
126}
127
128static int j721e_pcie_start_link(struct cdns_pcie *cdns_pcie)
129{
130	struct j721e_pcie *pcie = dev_get_drvdata(cdns_pcie->dev);
131	u32 reg;
132
133	reg = j721e_pcie_user_readl(pcie, J721E_PCIE_USER_CMD_STATUS);
134	reg |= LINK_TRAINING_ENABLE;
135	j721e_pcie_user_writel(pcie, J721E_PCIE_USER_CMD_STATUS, reg);
136
137	return 0;
138}
139
140static void j721e_pcie_stop_link(struct cdns_pcie *cdns_pcie)
141{
142	struct j721e_pcie *pcie = dev_get_drvdata(cdns_pcie->dev);
143	u32 reg;
144
145	reg = j721e_pcie_user_readl(pcie, J721E_PCIE_USER_CMD_STATUS);
146	reg &= ~LINK_TRAINING_ENABLE;
147	j721e_pcie_user_writel(pcie, J721E_PCIE_USER_CMD_STATUS, reg);
148}
149
150static bool j721e_pcie_link_up(struct cdns_pcie *cdns_pcie)
151{
152	struct j721e_pcie *pcie = dev_get_drvdata(cdns_pcie->dev);
153	u32 reg;
154
155	reg = j721e_pcie_user_readl(pcie, J721E_PCIE_USER_LINKSTATUS);
156	reg &= LINK_STATUS;
157	if (reg == LINK_UP_DL_COMPLETED)
158		return true;
159
160	return false;
161}
162
163static const struct cdns_pcie_ops j721e_pcie_ops = {
164	.start_link = j721e_pcie_start_link,
165	.stop_link = j721e_pcie_stop_link,
166	.link_up = j721e_pcie_link_up,
167};
168
169static int j721e_pcie_set_mode(struct j721e_pcie *pcie, struct regmap *syscon,
170			       unsigned int offset)
171{
172	struct device *dev = pcie->cdns_pcie->dev;
173	u32 mask = J721E_MODE_RC;
174	u32 mode = pcie->mode;
175	u32 val = 0;
176	int ret = 0;
177
178	if (mode == PCI_MODE_RC)
179		val = J721E_MODE_RC;
180
181	ret = regmap_update_bits(syscon, offset, mask, val);
182	if (ret)
183		dev_err(dev, "failed to set pcie mode\n");
184
185	return ret;
186}
187
188static int j721e_pcie_set_link_speed(struct j721e_pcie *pcie,
189				     struct regmap *syscon, unsigned int offset)
190{
191	struct device *dev = pcie->cdns_pcie->dev;
192	struct device_node *np = dev->of_node;
193	int link_speed;
194	u32 val = 0;
195	int ret;
196
197	link_speed = of_pci_get_max_link_speed(np);
198	if (link_speed < 2)
199		link_speed = 2;
200
201	val = link_speed - 1;
202	ret = regmap_update_bits(syscon, offset, GENERATION_SEL_MASK, val);
203	if (ret)
204		dev_err(dev, "failed to set link speed\n");
205
206	return ret;
207}
208
209static int j721e_pcie_set_lane_count(struct j721e_pcie *pcie,
210				     struct regmap *syscon, unsigned int offset)
211{
212	struct device *dev = pcie->cdns_pcie->dev;
213	u32 lanes = pcie->num_lanes;
214	u32 mask = BIT(8);
215	u32 val = 0;
216	int ret;
217
218	if (pcie->max_lanes == 4)
219		mask = GENMASK(9, 8);
220
221	val = LANE_COUNT(lanes - 1);
222	ret = regmap_update_bits(syscon, offset, mask, val);
223	if (ret)
224		dev_err(dev, "failed to set link count\n");
225
226	return ret;
227}
228
229static int j721e_enable_acspcie_refclk(struct j721e_pcie *pcie,
230				       struct regmap *syscon)
231{
232	struct device *dev = pcie->cdns_pcie->dev;
233	struct device_node *node = dev->of_node;
234	u32 mask = ACSPCIE_PAD_DISABLE_MASK;
235	struct of_phandle_args args;
236	u32 val;
237	int ret;
238
239	ret = of_parse_phandle_with_fixed_args(node,
240					       "ti,syscon-acspcie-proxy-ctrl",
241					       1, 0, &args);
242	if (ret) {
243		dev_err(dev,
244			"ti,syscon-acspcie-proxy-ctrl has invalid arguments\n");
245		return ret;
246	}
247
248	/* Clear PAD IO disable bits to enable refclk output */
249	val = ~(args.args[0]);
250	ret = regmap_update_bits(syscon, 0, mask, val);
251	if (ret) {
252		dev_err(dev, "failed to enable ACSPCIE refclk: %d\n", ret);
253		return ret;
254	}
255
256	return 0;
257}
258
259static int j721e_pcie_ctrl_init(struct j721e_pcie *pcie)
260{
261	struct device *dev = pcie->cdns_pcie->dev;
262	struct device_node *node = dev->of_node;
263	struct of_phandle_args args;
264	unsigned int offset = 0;
265	struct regmap *syscon;
266	int ret;
267
268	syscon = syscon_regmap_lookup_by_phandle(node, "ti,syscon-pcie-ctrl");
269	if (IS_ERR(syscon)) {
270		dev_err(dev, "Unable to get ti,syscon-pcie-ctrl regmap\n");
271		return PTR_ERR(syscon);
272	}
273
274	/* Do not error out to maintain old DT compatibility */
275	ret = of_parse_phandle_with_fixed_args(node, "ti,syscon-pcie-ctrl", 1,
276					       0, &args);
277	if (!ret)
278		offset = args.args[0];
279
280	ret = j721e_pcie_set_mode(pcie, syscon, offset);
281	if (ret < 0) {
282		dev_err(dev, "Failed to set pci mode\n");
283		return ret;
284	}
285
286	ret = j721e_pcie_set_link_speed(pcie, syscon, offset);
287	if (ret < 0) {
288		dev_err(dev, "Failed to set link speed\n");
289		return ret;
290	}
291
292	ret = j721e_pcie_set_lane_count(pcie, syscon, offset);
293	if (ret < 0) {
294		dev_err(dev, "Failed to set num-lanes\n");
295		return ret;
296	}
297
298	/* Enable ACSPCIE refclk output if the optional property exists */
299	syscon = syscon_regmap_lookup_by_phandle_optional(node,
300						"ti,syscon-acspcie-proxy-ctrl");
301	if (!syscon)
302		return 0;
303
304	return j721e_enable_acspcie_refclk(pcie, syscon);
305}
306
307static int cdns_ti_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
308				    int where, int size, u32 *value)
309{
310	if (pci_is_root_bus(bus))
311		return pci_generic_config_read32(bus, devfn, where, size,
312						 value);
313
314	return pci_generic_config_read(bus, devfn, where, size, value);
315}
316
317static int cdns_ti_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
318				     int where, int size, u32 value)
319{
320	if (pci_is_root_bus(bus))
321		return pci_generic_config_write32(bus, devfn, where, size,
322						  value);
323
324	return pci_generic_config_write(bus, devfn, where, size, value);
325}
326
327static struct pci_ops cdns_ti_pcie_host_ops = {
328	.map_bus	= cdns_pci_map_bus,
329	.read		= cdns_ti_pcie_config_read,
330	.write		= cdns_ti_pcie_config_write,
331};
332
333static const struct j721e_pcie_data j721e_pcie_rc_data = {
334	.mode = PCI_MODE_RC,
335	.quirk_retrain_flag = true,
336	.byte_access_allowed = false,
337	.linkdown_irq_regfield = LINK_DOWN,
338	.max_lanes = 2,
339};
340
341static const struct j721e_pcie_data j721e_pcie_ep_data = {
342	.mode = PCI_MODE_EP,
343	.linkdown_irq_regfield = LINK_DOWN,
344	.max_lanes = 2,
345};
346
347static const struct j721e_pcie_data j7200_pcie_rc_data = {
348	.mode = PCI_MODE_RC,
349	.quirk_detect_quiet_flag = true,
350	.linkdown_irq_regfield = J7200_LINK_DOWN,
351	.byte_access_allowed = true,
352	.max_lanes = 2,
353};
354
355static const struct j721e_pcie_data j7200_pcie_ep_data = {
356	.mode = PCI_MODE_EP,
357	.quirk_detect_quiet_flag = true,
358	.quirk_disable_flr = true,
359	.max_lanes = 2,
360};
361
362static const struct j721e_pcie_data am64_pcie_rc_data = {
363	.mode = PCI_MODE_RC,
364	.linkdown_irq_regfield = J7200_LINK_DOWN,
365	.byte_access_allowed = true,
366	.max_lanes = 1,
367};
368
369static const struct j721e_pcie_data am64_pcie_ep_data = {
370	.mode = PCI_MODE_EP,
371	.linkdown_irq_regfield = J7200_LINK_DOWN,
372	.max_lanes = 1,
373};
374
375static const struct j721e_pcie_data j784s4_pcie_rc_data = {
376	.mode = PCI_MODE_RC,
377	.quirk_retrain_flag = true,
378	.byte_access_allowed = false,
379	.linkdown_irq_regfield = LINK_DOWN,
380	.max_lanes = 4,
381};
382
383static const struct j721e_pcie_data j784s4_pcie_ep_data = {
384	.mode = PCI_MODE_EP,
385	.linkdown_irq_regfield = LINK_DOWN,
386	.max_lanes = 4,
387};
388
389static const struct j721e_pcie_data j722s_pcie_rc_data = {
390	.mode = PCI_MODE_RC,
391	.linkdown_irq_regfield = J7200_LINK_DOWN,
392	.byte_access_allowed = true,
393	.max_lanes = 1,
394};
395
396static const struct of_device_id of_j721e_pcie_match[] = {
397	{
398		.compatible = "ti,j721e-pcie-host",
399		.data = &j721e_pcie_rc_data,
400	},
401	{
402		.compatible = "ti,j721e-pcie-ep",
403		.data = &j721e_pcie_ep_data,
404	},
405	{
406		.compatible = "ti,j7200-pcie-host",
407		.data = &j7200_pcie_rc_data,
408	},
409	{
410		.compatible = "ti,j7200-pcie-ep",
411		.data = &j7200_pcie_ep_data,
412	},
413	{
414		.compatible = "ti,am64-pcie-host",
415		.data = &am64_pcie_rc_data,
416	},
417	{
418		.compatible = "ti,am64-pcie-ep",
419		.data = &am64_pcie_ep_data,
420	},
421	{
422		.compatible = "ti,j784s4-pcie-host",
423		.data = &j784s4_pcie_rc_data,
424	},
425	{
426		.compatible = "ti,j784s4-pcie-ep",
427		.data = &j784s4_pcie_ep_data,
428	},
429	{
430		.compatible = "ti,j722s-pcie-host",
431		.data = &j722s_pcie_rc_data,
432	},
433	{},
434};
435
436static int j721e_pcie_probe(struct platform_device *pdev)
437{
438	struct device *dev = &pdev->dev;
439	struct device_node *node = dev->of_node;
440	struct pci_host_bridge *bridge;
441	const struct j721e_pcie_data *data;
442	struct cdns_pcie *cdns_pcie;
443	struct j721e_pcie *pcie;
444	struct cdns_pcie_rc *rc = NULL;
445	struct cdns_pcie_ep *ep = NULL;
446	struct gpio_desc *gpiod;
447	void __iomem *base;
448	struct clk *clk;
449	u32 num_lanes;
450	u32 mode;
451	int ret;
452	int irq;
453
454	data = of_device_get_match_data(dev);
455	if (!data)
456		return -EINVAL;
457
458	mode = (u32)data->mode;
459
460	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
461	if (!pcie)
462		return -ENOMEM;
463
464	switch (mode) {
465	case PCI_MODE_RC:
466		if (!IS_ENABLED(CONFIG_PCIE_CADENCE_HOST))
467			return -ENODEV;
468
469		bridge = devm_pci_alloc_host_bridge(dev, sizeof(*rc));
470		if (!bridge)
471			return -ENOMEM;
472
473		if (!data->byte_access_allowed)
474			bridge->ops = &cdns_ti_pcie_host_ops;
475		rc = pci_host_bridge_priv(bridge);
476		rc->quirk_retrain_flag = data->quirk_retrain_flag;
477		rc->quirk_detect_quiet_flag = data->quirk_detect_quiet_flag;
478
479		cdns_pcie = &rc->pcie;
480		cdns_pcie->dev = dev;
481		cdns_pcie->ops = &j721e_pcie_ops;
482		pcie->cdns_pcie = cdns_pcie;
483		break;
484	case PCI_MODE_EP:
485		if (!IS_ENABLED(CONFIG_PCIE_CADENCE_EP))
486			return -ENODEV;
487
488		ep = devm_kzalloc(dev, sizeof(*ep), GFP_KERNEL);
489		if (!ep)
490			return -ENOMEM;
491
492		ep->quirk_detect_quiet_flag = data->quirk_detect_quiet_flag;
493		ep->quirk_disable_flr = data->quirk_disable_flr;
494
495		cdns_pcie = &ep->pcie;
496		cdns_pcie->dev = dev;
497		cdns_pcie->ops = &j721e_pcie_ops;
498		pcie->cdns_pcie = cdns_pcie;
499		break;
500	default:
501		dev_err(dev, "INVALID device type %d\n", mode);
502		return 0;
503	}
504
505	pcie->mode = mode;
506	pcie->linkdown_irq_regfield = data->linkdown_irq_regfield;
507
508	base = devm_platform_ioremap_resource_byname(pdev, "intd_cfg");
509	if (IS_ERR(base))
510		return PTR_ERR(base);
511	pcie->intd_cfg_base = base;
512
513	base = devm_platform_ioremap_resource_byname(pdev, "user_cfg");
514	if (IS_ERR(base))
515		return PTR_ERR(base);
516	pcie->user_cfg_base = base;
517
518	ret = of_property_read_u32(node, "num-lanes", &num_lanes);
519	if (ret || num_lanes > data->max_lanes) {
520		dev_warn(dev, "num-lanes property not provided or invalid, setting num-lanes to 1\n");
521		num_lanes = 1;
522	}
523
524	pcie->num_lanes = num_lanes;
525	pcie->max_lanes = data->max_lanes;
526
527	if (dma_set_mask_and_coherent(dev, DMA_BIT_MASK(48)))
528		return -EINVAL;
529
530	irq = platform_get_irq_byname(pdev, "link_state");
531	if (irq < 0)
532		return irq;
533
534	dev_set_drvdata(dev, pcie);
535	pm_runtime_enable(dev);
536	ret = pm_runtime_get_sync(dev);
537	if (ret < 0) {
538		dev_err_probe(dev, ret, "pm_runtime_get_sync failed\n");
539		goto err_get_sync;
540	}
541
542	ret = j721e_pcie_ctrl_init(pcie);
543	if (ret < 0) {
544		dev_err_probe(dev, ret, "pm_runtime_get_sync failed\n");
545		goto err_get_sync;
546	}
547
548	ret = devm_request_irq(dev, irq, j721e_pcie_link_irq_handler, 0,
549			       "j721e-pcie-link-down-irq", pcie);
550	if (ret < 0) {
551		dev_err_probe(dev, ret, "failed to request link state IRQ %d\n", irq);
552		goto err_get_sync;
553	}
554
555	j721e_pcie_config_link_irq(pcie);
556
557	switch (mode) {
558	case PCI_MODE_RC:
559		gpiod = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
560		if (IS_ERR(gpiod)) {
561			ret = dev_err_probe(dev, PTR_ERR(gpiod), "Failed to get reset GPIO\n");
562			goto err_get_sync;
563		}
564		pcie->reset_gpio = gpiod;
565
566		ret = cdns_pcie_init_phy(dev, cdns_pcie);
567		if (ret) {
568			dev_err_probe(dev, ret, "Failed to init phy\n");
569			goto err_get_sync;
570		}
571
572		clk = devm_clk_get_optional(dev, "pcie_refclk");
573		if (IS_ERR(clk)) {
574			ret = dev_err_probe(dev, PTR_ERR(clk), "failed to get pcie_refclk\n");
575			goto err_pcie_setup;
576		}
577
578		ret = clk_prepare_enable(clk);
579		if (ret) {
580			dev_err_probe(dev, ret, "failed to enable pcie_refclk\n");
581			goto err_pcie_setup;
582		}
583		pcie->refclk = clk;
584
585		/*
586		 * Section 2.2 of the PCI Express Card Electromechanical
587		 * Specification (Revision 5.1) mandates that the deassertion
588		 * of the PERST# signal should be delayed by 100 ms (TPVPERL).
589		 * This shall ensure that the power and the reference clock
590		 * are stable.
591		 */
592		if (gpiod) {
593			msleep(PCIE_T_PVPERL_MS);
594			gpiod_set_value_cansleep(gpiod, 1);
595		}
596
597		ret = cdns_pcie_host_setup(rc);
598		if (ret < 0) {
599			clk_disable_unprepare(pcie->refclk);
600			goto err_pcie_setup;
601		}
602
603		break;
604	case PCI_MODE_EP:
605		ret = cdns_pcie_init_phy(dev, cdns_pcie);
606		if (ret) {
607			dev_err_probe(dev, ret, "Failed to init phy\n");
608			goto err_get_sync;
609		}
610
611		ret = cdns_pcie_ep_setup(ep);
612		if (ret < 0)
613			goto err_pcie_setup;
614
615		break;
616	}
617
618	return 0;
619
620err_pcie_setup:
621	cdns_pcie_disable_phy(cdns_pcie);
622
623err_get_sync:
624	pm_runtime_put(dev);
625	pm_runtime_disable(dev);
626
627	return ret;
628}
629
630static void j721e_pcie_remove(struct platform_device *pdev)
631{
632	struct j721e_pcie *pcie = platform_get_drvdata(pdev);
633	struct cdns_pcie *cdns_pcie = pcie->cdns_pcie;
634	struct device *dev = &pdev->dev;
635
636	clk_disable_unprepare(pcie->refclk);
637	cdns_pcie_disable_phy(cdns_pcie);
638	pm_runtime_put(dev);
639	pm_runtime_disable(dev);
640}
641
642static int j721e_pcie_suspend_noirq(struct device *dev)
643{
644	struct j721e_pcie *pcie = dev_get_drvdata(dev);
645
646	if (pcie->mode == PCI_MODE_RC) {
647		gpiod_set_value_cansleep(pcie->reset_gpio, 0);
648		clk_disable_unprepare(pcie->refclk);
649	}
650
651	cdns_pcie_disable_phy(pcie->cdns_pcie);
652
653	return 0;
654}
655
656static int j721e_pcie_resume_noirq(struct device *dev)
657{
658	struct j721e_pcie *pcie = dev_get_drvdata(dev);
659	struct cdns_pcie *cdns_pcie = pcie->cdns_pcie;
660	int ret;
661
662	ret = j721e_pcie_ctrl_init(pcie);
663	if (ret < 0)
664		return ret;
665
666	j721e_pcie_config_link_irq(pcie);
667
668	/*
669	 * This is not called explicitly in the probe, it is called by
670	 * cdns_pcie_init_phy().
671	 */
672	ret = cdns_pcie_enable_phy(pcie->cdns_pcie);
673	if (ret < 0)
674		return ret;
675
676	if (pcie->mode == PCI_MODE_RC) {
677		struct cdns_pcie_rc *rc = cdns_pcie_to_rc(cdns_pcie);
678
679		ret = clk_prepare_enable(pcie->refclk);
680		if (ret < 0)
681			return ret;
682
683		/*
684		 * Section 2.2 of the PCI Express Card Electromechanical
685		 * Specification (Revision 5.1) mandates that the deassertion
686		 * of the PERST# signal should be delayed by 100 ms (TPVPERL).
687		 * This shall ensure that the power and the reference clock
688		 * are stable.
689		 */
690		if (pcie->reset_gpio) {
691			msleep(PCIE_T_PVPERL_MS);
692			gpiod_set_value_cansleep(pcie->reset_gpio, 1);
693		}
694
695		ret = cdns_pcie_host_link_setup(rc);
696		if (ret < 0) {
697			clk_disable_unprepare(pcie->refclk);
698			return ret;
699		}
700
701		/*
702		 * Reset internal status of BARs to force reinitialization in
703		 * cdns_pcie_host_init().
704		 */
705		for (enum cdns_pcie_rp_bar bar = RP_BAR0; bar <= RP_NO_BAR; bar++)
706			rc->avail_ib_bar[bar] = true;
707
708		ret = cdns_pcie_host_init(rc);
709		if (ret) {
710			clk_disable_unprepare(pcie->refclk);
711			return ret;
712		}
713	}
714
715	return 0;
716}
717
718static DEFINE_NOIRQ_DEV_PM_OPS(j721e_pcie_pm_ops,
719			       j721e_pcie_suspend_noirq,
720			       j721e_pcie_resume_noirq);
721
722static struct platform_driver j721e_pcie_driver = {
723	.probe  = j721e_pcie_probe,
724	.remove = j721e_pcie_remove,
725	.driver = {
726		.name	= "j721e-pcie",
727		.of_match_table = of_j721e_pcie_match,
728		.suppress_bind_attrs = true,
729		.pm	= pm_sleep_ptr(&j721e_pcie_pm_ops),
730	},
731};
732builtin_platform_driver(j721e_pcie_driver);