1// SPDX-License-Identifier: GPL-2.0
2/*
3 * MediaTek PCIe host controller driver.
4 *
5 * Copyright (c) 2020 MediaTek Inc.
6 * Author: Jianjun Wang <jianjun.wang@mediatek.com>
7 */
8
9#include <linux/clk.h>
10#include <linux/delay.h>
11#include <linux/iopoll.h>
12#include <linux/irq.h>
13#include <linux/irqchip/chained_irq.h>
14#include <linux/irqdomain.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/msi.h>
18#include <linux/pci.h>
19#include <linux/phy/phy.h>
20#include <linux/platform_device.h>
21#include <linux/pm_domain.h>
22#include <linux/pm_runtime.h>
23#include <linux/reset.h>
24
25#include "../pci.h"
26
27#define PCIE_SETTING_REG		0x80
28#define PCIE_PCI_IDS_1			0x9c
29#define PCI_CLASS(class)		(class << 8)
30#define PCIE_RC_MODE			BIT(0)
31
32#define PCIE_CFGNUM_REG			0x140
33#define PCIE_CFG_DEVFN(devfn)		((devfn) & GENMASK(7, 0))
34#define PCIE_CFG_BUS(bus)		(((bus) << 8) & GENMASK(15, 8))
35#define PCIE_CFG_BYTE_EN(bytes)		(((bytes) << 16) & GENMASK(19, 16))
36#define PCIE_CFG_FORCE_BYTE_EN		BIT(20)
37#define PCIE_CFG_OFFSET_ADDR		0x1000
38#define PCIE_CFG_HEADER(bus, devfn) \
39	(PCIE_CFG_BUS(bus) | PCIE_CFG_DEVFN(devfn))
40
41#define PCIE_RST_CTRL_REG		0x148
42#define PCIE_MAC_RSTB			BIT(0)
43#define PCIE_PHY_RSTB			BIT(1)
44#define PCIE_BRG_RSTB			BIT(2)
45#define PCIE_PE_RSTB			BIT(3)
46
47#define PCIE_LTSSM_STATUS_REG		0x150
48#define PCIE_LTSSM_STATE_MASK		GENMASK(28, 24)
49#define PCIE_LTSSM_STATE(val)		((val & PCIE_LTSSM_STATE_MASK) >> 24)
50#define PCIE_LTSSM_STATE_L2_IDLE	0x14
51
52#define PCIE_LINK_STATUS_REG		0x154
53#define PCIE_PORT_LINKUP		BIT(8)
54
55#define PCIE_MSI_SET_NUM		8
56#define PCIE_MSI_IRQS_PER_SET		32
57#define PCIE_MSI_IRQS_NUM \
58	(PCIE_MSI_IRQS_PER_SET * PCIE_MSI_SET_NUM)
59
60#define PCIE_INT_ENABLE_REG		0x180
61#define PCIE_MSI_ENABLE			GENMASK(PCIE_MSI_SET_NUM + 8 - 1, 8)
62#define PCIE_MSI_SHIFT			8
63#define PCIE_INTX_SHIFT			24
64#define PCIE_INTX_ENABLE \
65	GENMASK(PCIE_INTX_SHIFT + PCI_NUM_INTX - 1, PCIE_INTX_SHIFT)
66
67#define PCIE_INT_STATUS_REG		0x184
68#define PCIE_MSI_SET_ENABLE_REG		0x190
69#define PCIE_MSI_SET_ENABLE		GENMASK(PCIE_MSI_SET_NUM - 1, 0)
70
71#define PCIE_MSI_SET_BASE_REG		0xc00
72#define PCIE_MSI_SET_OFFSET		0x10
73#define PCIE_MSI_SET_STATUS_OFFSET	0x04
74#define PCIE_MSI_SET_ENABLE_OFFSET	0x08
75
76#define PCIE_MSI_SET_ADDR_HI_BASE	0xc80
77#define PCIE_MSI_SET_ADDR_HI_OFFSET	0x04
78
79#define PCIE_ICMD_PM_REG		0x198
80#define PCIE_TURN_OFF_LINK		BIT(4)
81
82#define PCIE_MISC_CTRL_REG		0x348
83#define PCIE_DISABLE_DVFSRC_VLT_REQ	BIT(1)
84
85#define PCIE_TRANS_TABLE_BASE_REG	0x800
86#define PCIE_ATR_SRC_ADDR_MSB_OFFSET	0x4
87#define PCIE_ATR_TRSL_ADDR_LSB_OFFSET	0x8
88#define PCIE_ATR_TRSL_ADDR_MSB_OFFSET	0xc
89#define PCIE_ATR_TRSL_PARAM_OFFSET	0x10
90#define PCIE_ATR_TLB_SET_OFFSET		0x20
91
92#define PCIE_MAX_TRANS_TABLES		8
93#define PCIE_ATR_EN			BIT(0)
94#define PCIE_ATR_SIZE(size) \
95	(((((size) - 1) << 1) & GENMASK(6, 1)) | PCIE_ATR_EN)
96#define PCIE_ATR_ID(id)			((id) & GENMASK(3, 0))
97#define PCIE_ATR_TYPE_MEM		PCIE_ATR_ID(0)
98#define PCIE_ATR_TYPE_IO		PCIE_ATR_ID(1)
99#define PCIE_ATR_TLP_TYPE(type)		(((type) << 16) & GENMASK(18, 16))
100#define PCIE_ATR_TLP_TYPE_MEM		PCIE_ATR_TLP_TYPE(0)
101#define PCIE_ATR_TLP_TYPE_IO		PCIE_ATR_TLP_TYPE(2)
102
103/**
104 * struct mtk_msi_set - MSI information for each set
105 * @base: IO mapped register base
106 * @msg_addr: MSI message address
107 * @saved_irq_state: IRQ enable state saved at suspend time
108 */
109struct mtk_msi_set {
110	void __iomem *base;
111	phys_addr_t msg_addr;
112	u32 saved_irq_state;
113};
114
115/**
116 * struct mtk_gen3_pcie - PCIe port information
117 * @dev: pointer to PCIe device
118 * @base: IO mapped register base
119 * @reg_base: physical register base
120 * @mac_reset: MAC reset control
121 * @phy_reset: PHY reset control
122 * @phy: PHY controller block
123 * @clks: PCIe clocks
124 * @num_clks: PCIe clocks count for this port
125 * @irq: PCIe controller interrupt number
126 * @saved_irq_state: IRQ enable state saved at suspend time
127 * @irq_lock: lock protecting IRQ register access
128 * @intx_domain: legacy INTx IRQ domain
129 * @msi_domain: MSI IRQ domain
130 * @msi_bottom_domain: MSI IRQ bottom domain
131 * @msi_sets: MSI sets information
132 * @lock: lock protecting IRQ bit map
133 * @msi_irq_in_use: bit map for assigned MSI IRQ
134 */
135struct mtk_gen3_pcie {
136	struct device *dev;
137	void __iomem *base;
138	phys_addr_t reg_base;
139	struct reset_control *mac_reset;
140	struct reset_control *phy_reset;
141	struct phy *phy;
142	struct clk_bulk_data *clks;
143	int num_clks;
144
145	int irq;
146	u32 saved_irq_state;
147	raw_spinlock_t irq_lock;
148	struct irq_domain *intx_domain;
149	struct irq_domain *msi_domain;
150	struct irq_domain *msi_bottom_domain;
151	struct mtk_msi_set msi_sets[PCIE_MSI_SET_NUM];
152	struct mutex lock;
153	DECLARE_BITMAP(msi_irq_in_use, PCIE_MSI_IRQS_NUM);
154};
155
156/* LTSSM state in PCIE_LTSSM_STATUS_REG bit[28:24] */
157static const char *const ltssm_str[] = {
158	"detect.quiet",			/* 0x00 */
159	"detect.active",		/* 0x01 */
160	"polling.active",		/* 0x02 */
161	"polling.compliance",		/* 0x03 */
162	"polling.configuration",	/* 0x04 */
163	"config.linkwidthstart",	/* 0x05 */
164	"config.linkwidthaccept",	/* 0x06 */
165	"config.lanenumwait",		/* 0x07 */
166	"config.lanenumaccept",		/* 0x08 */
167	"config.complete",		/* 0x09 */
168	"config.idle",			/* 0x0A */
169	"recovery.receiverlock",	/* 0x0B */
170	"recovery.equalization",	/* 0x0C */
171	"recovery.speed",		/* 0x0D */
172	"recovery.receiverconfig",	/* 0x0E */
173	"recovery.idle",		/* 0x0F */
174	"L0",				/* 0x10 */
175	"L0s",				/* 0x11 */
176	"L1.entry",			/* 0x12 */
177	"L1.idle",			/* 0x13 */
178	"L2.idle",			/* 0x14 */
179	"L2.transmitwake",		/* 0x15 */
180	"disable",			/* 0x16 */
181	"loopback.entry",		/* 0x17 */
182	"loopback.active",		/* 0x18 */
183	"loopback.exit",		/* 0x19 */
184	"hotreset",			/* 0x1A */
185};
186
187/**
188 * mtk_pcie_config_tlp_header() - Configure a configuration TLP header
189 * @bus: PCI bus to query
190 * @devfn: device/function number
191 * @where: offset in config space
192 * @size: data size in TLP header
193 *
194 * Set byte enable field and device information in configuration TLP header.
195 */
196static void mtk_pcie_config_tlp_header(struct pci_bus *bus, unsigned int devfn,
197					int where, int size)
198{
199	struct mtk_gen3_pcie *pcie = bus->sysdata;
200	int bytes;
201	u32 val;
202
203	bytes = (GENMASK(size - 1, 0) & 0xf) << (where & 0x3);
204
205	val = PCIE_CFG_FORCE_BYTE_EN | PCIE_CFG_BYTE_EN(bytes) |
206	      PCIE_CFG_HEADER(bus->number, devfn);
207
208	writel_relaxed(val, pcie->base + PCIE_CFGNUM_REG);
209}
210
211static void __iomem *mtk_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
212				      int where)
213{
214	struct mtk_gen3_pcie *pcie = bus->sysdata;
215
216	return pcie->base + PCIE_CFG_OFFSET_ADDR + where;
217}
218
219static int mtk_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
220				int where, int size, u32 *val)
221{
222	mtk_pcie_config_tlp_header(bus, devfn, where, size);
223
224	return pci_generic_config_read32(bus, devfn, where, size, val);
225}
226
227static int mtk_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
228				 int where, int size, u32 val)
229{
230	mtk_pcie_config_tlp_header(bus, devfn, where, size);
231
232	if (size <= 2)
233		val <<= (where & 0x3) * 8;
234
235	return pci_generic_config_write32(bus, devfn, where, 4, val);
236}
237
238static struct pci_ops mtk_pcie_ops = {
239	.map_bus = mtk_pcie_map_bus,
240	.read  = mtk_pcie_config_read,
241	.write = mtk_pcie_config_write,
242};
243
244static int mtk_pcie_set_trans_table(struct mtk_gen3_pcie *pcie,
245				    resource_size_t cpu_addr,
246				    resource_size_t pci_addr,
247				    resource_size_t size,
248				    unsigned long type, int *num)
249{
250	resource_size_t remaining = size;
251	resource_size_t table_size;
252	resource_size_t addr_align;
253	const char *range_type;
254	void __iomem *table;
255	u32 val;
256
257	while (remaining && (*num < PCIE_MAX_TRANS_TABLES)) {
258		/* Table size needs to be a power of 2 */
259		table_size = BIT(fls(remaining) - 1);
260
261		if (cpu_addr > 0) {
262			addr_align = BIT(ffs(cpu_addr) - 1);
263			table_size = min(table_size, addr_align);
264		}
265
266		/* Minimum size of translate table is 4KiB */
267		if (table_size < 0x1000) {
268			dev_err(pcie->dev, "illegal table size %#llx\n",
269				(unsigned long long)table_size);
270			return -EINVAL;
271		}
272
273		table = pcie->base + PCIE_TRANS_TABLE_BASE_REG + *num * PCIE_ATR_TLB_SET_OFFSET;
274		writel_relaxed(lower_32_bits(cpu_addr) | PCIE_ATR_SIZE(fls(table_size) - 1), table);
275		writel_relaxed(upper_32_bits(cpu_addr), table + PCIE_ATR_SRC_ADDR_MSB_OFFSET);
276		writel_relaxed(lower_32_bits(pci_addr), table + PCIE_ATR_TRSL_ADDR_LSB_OFFSET);
277		writel_relaxed(upper_32_bits(pci_addr), table + PCIE_ATR_TRSL_ADDR_MSB_OFFSET);
278
279		if (type == IORESOURCE_IO) {
280			val = PCIE_ATR_TYPE_IO | PCIE_ATR_TLP_TYPE_IO;
281			range_type = "IO";
282		} else {
283			val = PCIE_ATR_TYPE_MEM | PCIE_ATR_TLP_TYPE_MEM;
284			range_type = "MEM";
285		}
286
287		writel_relaxed(val, table + PCIE_ATR_TRSL_PARAM_OFFSET);
288
289		dev_dbg(pcie->dev, "set %s trans window[%d]: cpu_addr = %#llx, pci_addr = %#llx, size = %#llx\n",
290			range_type, *num, (unsigned long long)cpu_addr,
291			(unsigned long long)pci_addr, (unsigned long long)table_size);
292
293		cpu_addr += table_size;
294		pci_addr += table_size;
295		remaining -= table_size;
296		(*num)++;
297	}
298
299	if (remaining)
300		dev_warn(pcie->dev, "not enough translate table for addr: %#llx, limited to [%d]\n",
301			 (unsigned long long)cpu_addr, PCIE_MAX_TRANS_TABLES);
302
303	return 0;
304}
305
306static void mtk_pcie_enable_msi(struct mtk_gen3_pcie *pcie)
307{
308	int i;
309	u32 val;
310
311	for (i = 0; i < PCIE_MSI_SET_NUM; i++) {
312		struct mtk_msi_set *msi_set = &pcie->msi_sets[i];
313
314		msi_set->base = pcie->base + PCIE_MSI_SET_BASE_REG +
315				i * PCIE_MSI_SET_OFFSET;
316		msi_set->msg_addr = pcie->reg_base + PCIE_MSI_SET_BASE_REG +
317				    i * PCIE_MSI_SET_OFFSET;
318
319		/* Configure the MSI capture address */
320		writel_relaxed(lower_32_bits(msi_set->msg_addr), msi_set->base);
321		writel_relaxed(upper_32_bits(msi_set->msg_addr),
322			       pcie->base + PCIE_MSI_SET_ADDR_HI_BASE +
323			       i * PCIE_MSI_SET_ADDR_HI_OFFSET);
324	}
325
326	val = readl_relaxed(pcie->base + PCIE_MSI_SET_ENABLE_REG);
327	val |= PCIE_MSI_SET_ENABLE;
328	writel_relaxed(val, pcie->base + PCIE_MSI_SET_ENABLE_REG);
329
330	val = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
331	val |= PCIE_MSI_ENABLE;
332	writel_relaxed(val, pcie->base + PCIE_INT_ENABLE_REG);
333}
334
335static int mtk_pcie_startup_port(struct mtk_gen3_pcie *pcie)
336{
337	struct resource_entry *entry;
338	struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
339	unsigned int table_index = 0;
340	int err;
341	u32 val;
342
343	/* Set as RC mode */
344	val = readl_relaxed(pcie->base + PCIE_SETTING_REG);
345	val |= PCIE_RC_MODE;
346	writel_relaxed(val, pcie->base + PCIE_SETTING_REG);
347
348	/* Set class code */
349	val = readl_relaxed(pcie->base + PCIE_PCI_IDS_1);
350	val &= ~GENMASK(31, 8);
351	val |= PCI_CLASS(PCI_CLASS_BRIDGE_PCI_NORMAL);
352	writel_relaxed(val, pcie->base + PCIE_PCI_IDS_1);
353
354	/* Mask all INTx interrupts */
355	val = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
356	val &= ~PCIE_INTX_ENABLE;
357	writel_relaxed(val, pcie->base + PCIE_INT_ENABLE_REG);
358
359	/* Disable DVFSRC voltage request */
360	val = readl_relaxed(pcie->base + PCIE_MISC_CTRL_REG);
361	val |= PCIE_DISABLE_DVFSRC_VLT_REQ;
362	writel_relaxed(val, pcie->base + PCIE_MISC_CTRL_REG);
363
364	/* Assert all reset signals */
365	val = readl_relaxed(pcie->base + PCIE_RST_CTRL_REG);
366	val |= PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB | PCIE_PE_RSTB;
367	writel_relaxed(val, pcie->base + PCIE_RST_CTRL_REG);
368
369	/*
370	 * Described in PCIe CEM specification sections 2.2 (PERST# Signal)
371	 * and 2.2.1 (Initial Power-Up (G3 to S0)).
372	 * The deassertion of PERST# should be delayed 100ms (TPVPERL)
373	 * for the power and clock to become stable.
374	 */
375	msleep(100);
376
377	/* De-assert reset signals */
378	val &= ~(PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB | PCIE_PE_RSTB);
379	writel_relaxed(val, pcie->base + PCIE_RST_CTRL_REG);
380
381	/* Check if the link is up or not */
382	err = readl_poll_timeout(pcie->base + PCIE_LINK_STATUS_REG, val,
383				 !!(val & PCIE_PORT_LINKUP), 20,
384				 PCI_PM_D3COLD_WAIT * USEC_PER_MSEC);
385	if (err) {
386		const char *ltssm_state;
387		int ltssm_index;
388
389		val = readl_relaxed(pcie->base + PCIE_LTSSM_STATUS_REG);
390		ltssm_index = PCIE_LTSSM_STATE(val);
391		ltssm_state = ltssm_index >= ARRAY_SIZE(ltssm_str) ?
392			      "Unknown state" : ltssm_str[ltssm_index];
393		dev_err(pcie->dev,
394			"PCIe link down, current LTSSM state: %s (%#x)\n",
395			ltssm_state, val);
396		return err;
397	}
398
399	mtk_pcie_enable_msi(pcie);
400
401	/* Set PCIe translation windows */
402	resource_list_for_each_entry(entry, &host->windows) {
403		struct resource *res = entry->res;
404		unsigned long type = resource_type(res);
405		resource_size_t cpu_addr;
406		resource_size_t pci_addr;
407		resource_size_t size;
408
409		if (type == IORESOURCE_IO)
410			cpu_addr = pci_pio_to_address(res->start);
411		else if (type == IORESOURCE_MEM)
412			cpu_addr = res->start;
413		else
414			continue;
415
416		pci_addr = res->start - entry->offset;
417		size = resource_size(res);
418		err = mtk_pcie_set_trans_table(pcie, cpu_addr, pci_addr, size,
419					       type, &table_index);
420		if (err)
421			return err;
422	}
423
424	return 0;
425}
426
427static int mtk_pcie_set_affinity(struct irq_data *data,
428				 const struct cpumask *mask, bool force)
429{
430	return -EINVAL;
431}
432
433static void mtk_pcie_msi_irq_mask(struct irq_data *data)
434{
435	pci_msi_mask_irq(data);
436	irq_chip_mask_parent(data);
437}
438
439static void mtk_pcie_msi_irq_unmask(struct irq_data *data)
440{
441	pci_msi_unmask_irq(data);
442	irq_chip_unmask_parent(data);
443}
444
445static struct irq_chip mtk_msi_irq_chip = {
446	.irq_ack = irq_chip_ack_parent,
447	.irq_mask = mtk_pcie_msi_irq_mask,
448	.irq_unmask = mtk_pcie_msi_irq_unmask,
449	.name = "MSI",
450};
451
452static struct msi_domain_info mtk_msi_domain_info = {
453	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
454		   MSI_FLAG_PCI_MSIX | MSI_FLAG_MULTI_PCI_MSI),
455	.chip	= &mtk_msi_irq_chip,
456};
457
458static void mtk_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
459{
460	struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
461	struct mtk_gen3_pcie *pcie = data->domain->host_data;
462	unsigned long hwirq;
463
464	hwirq =	data->hwirq % PCIE_MSI_IRQS_PER_SET;
465
466	msg->address_hi = upper_32_bits(msi_set->msg_addr);
467	msg->address_lo = lower_32_bits(msi_set->msg_addr);
468	msg->data = hwirq;
469	dev_dbg(pcie->dev, "msi#%#lx address_hi %#x address_lo %#x data %d\n",
470		hwirq, msg->address_hi, msg->address_lo, msg->data);
471}
472
473static void mtk_msi_bottom_irq_ack(struct irq_data *data)
474{
475	struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
476	unsigned long hwirq;
477
478	hwirq =	data->hwirq % PCIE_MSI_IRQS_PER_SET;
479
480	writel_relaxed(BIT(hwirq), msi_set->base + PCIE_MSI_SET_STATUS_OFFSET);
481}
482
483static void mtk_msi_bottom_irq_mask(struct irq_data *data)
484{
485	struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
486	struct mtk_gen3_pcie *pcie = data->domain->host_data;
487	unsigned long hwirq, flags;
488	u32 val;
489
490	hwirq =	data->hwirq % PCIE_MSI_IRQS_PER_SET;
491
492	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
493	val = readl_relaxed(msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
494	val &= ~BIT(hwirq);
495	writel_relaxed(val, msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
496	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
497}
498
499static void mtk_msi_bottom_irq_unmask(struct irq_data *data)
500{
501	struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
502	struct mtk_gen3_pcie *pcie = data->domain->host_data;
503	unsigned long hwirq, flags;
504	u32 val;
505
506	hwirq =	data->hwirq % PCIE_MSI_IRQS_PER_SET;
507
508	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
509	val = readl_relaxed(msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
510	val |= BIT(hwirq);
511	writel_relaxed(val, msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
512	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
513}
514
515static struct irq_chip mtk_msi_bottom_irq_chip = {
516	.irq_ack		= mtk_msi_bottom_irq_ack,
517	.irq_mask		= mtk_msi_bottom_irq_mask,
518	.irq_unmask		= mtk_msi_bottom_irq_unmask,
519	.irq_compose_msi_msg	= mtk_compose_msi_msg,
520	.irq_set_affinity	= mtk_pcie_set_affinity,
521	.name			= "MSI",
522};
523
524static int mtk_msi_bottom_domain_alloc(struct irq_domain *domain,
525				       unsigned int virq, unsigned int nr_irqs,
526				       void *arg)
527{
528	struct mtk_gen3_pcie *pcie = domain->host_data;
529	struct mtk_msi_set *msi_set;
530	int i, hwirq, set_idx;
531
532	mutex_lock(&pcie->lock);
533
534	hwirq = bitmap_find_free_region(pcie->msi_irq_in_use, PCIE_MSI_IRQS_NUM,
535					order_base_2(nr_irqs));
536
537	mutex_unlock(&pcie->lock);
538
539	if (hwirq < 0)
540		return -ENOSPC;
541
542	set_idx = hwirq / PCIE_MSI_IRQS_PER_SET;
543	msi_set = &pcie->msi_sets[set_idx];
544
545	for (i = 0; i < nr_irqs; i++)
546		irq_domain_set_info(domain, virq + i, hwirq + i,
547				    &mtk_msi_bottom_irq_chip, msi_set,
548				    handle_edge_irq, NULL, NULL);
549
550	return 0;
551}
552
553static void mtk_msi_bottom_domain_free(struct irq_domain *domain,
554				       unsigned int virq, unsigned int nr_irqs)
555{
556	struct mtk_gen3_pcie *pcie = domain->host_data;
557	struct irq_data *data = irq_domain_get_irq_data(domain, virq);
558
559	mutex_lock(&pcie->lock);
560
561	bitmap_release_region(pcie->msi_irq_in_use, data->hwirq,
562			      order_base_2(nr_irqs));
563
564	mutex_unlock(&pcie->lock);
565
566	irq_domain_free_irqs_common(domain, virq, nr_irqs);
567}
568
569static const struct irq_domain_ops mtk_msi_bottom_domain_ops = {
570	.alloc = mtk_msi_bottom_domain_alloc,
571	.free = mtk_msi_bottom_domain_free,
572};
573
574static void mtk_intx_mask(struct irq_data *data)
575{
576	struct mtk_gen3_pcie *pcie = irq_data_get_irq_chip_data(data);
577	unsigned long flags;
578	u32 val;
579
580	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
581	val = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
582	val &= ~BIT(data->hwirq + PCIE_INTX_SHIFT);
583	writel_relaxed(val, pcie->base + PCIE_INT_ENABLE_REG);
584	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
585}
586
587static void mtk_intx_unmask(struct irq_data *data)
588{
589	struct mtk_gen3_pcie *pcie = irq_data_get_irq_chip_data(data);
590	unsigned long flags;
591	u32 val;
592
593	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
594	val = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
595	val |= BIT(data->hwirq + PCIE_INTX_SHIFT);
596	writel_relaxed(val, pcie->base + PCIE_INT_ENABLE_REG);
597	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
598}
599
600/**
601 * mtk_intx_eoi() - Clear INTx IRQ status at the end of interrupt
602 * @data: pointer to chip specific data
603 *
604 * As an emulated level IRQ, its interrupt status will remain
605 * until the corresponding de-assert message is received; hence that
606 * the status can only be cleared when the interrupt has been serviced.
607 */
608static void mtk_intx_eoi(struct irq_data *data)
609{
610	struct mtk_gen3_pcie *pcie = irq_data_get_irq_chip_data(data);
611	unsigned long hwirq;
612
613	hwirq = data->hwirq + PCIE_INTX_SHIFT;
614	writel_relaxed(BIT(hwirq), pcie->base + PCIE_INT_STATUS_REG);
615}
616
617static struct irq_chip mtk_intx_irq_chip = {
618	.irq_mask		= mtk_intx_mask,
619	.irq_unmask		= mtk_intx_unmask,
620	.irq_eoi		= mtk_intx_eoi,
621	.irq_set_affinity	= mtk_pcie_set_affinity,
622	.name			= "INTx",
623};
624
625static int mtk_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
626			     irq_hw_number_t hwirq)
627{
628	irq_set_chip_data(irq, domain->host_data);
629	irq_set_chip_and_handler_name(irq, &mtk_intx_irq_chip,
630				      handle_fasteoi_irq, "INTx");
631	return 0;
632}
633
634static const struct irq_domain_ops intx_domain_ops = {
635	.map = mtk_pcie_intx_map,
636};
637
638static int mtk_pcie_init_irq_domains(struct mtk_gen3_pcie *pcie)
639{
640	struct device *dev = pcie->dev;
641	struct device_node *intc_node, *node = dev->of_node;
642	int ret;
643
644	raw_spin_lock_init(&pcie->irq_lock);
645
646	/* Setup INTx */
647	intc_node = of_get_child_by_name(node, "interrupt-controller");
648	if (!intc_node) {
649		dev_err(dev, "missing interrupt-controller node\n");
650		return -ENODEV;
651	}
652
653	pcie->intx_domain = irq_domain_add_linear(intc_node, PCI_NUM_INTX,
654						  &intx_domain_ops, pcie);
655	if (!pcie->intx_domain) {
656		dev_err(dev, "failed to create INTx IRQ domain\n");
657		ret = -ENODEV;
658		goto out_put_node;
659	}
660
661	/* Setup MSI */
662	mutex_init(&pcie->lock);
663
664	pcie->msi_bottom_domain = irq_domain_add_linear(node, PCIE_MSI_IRQS_NUM,
665				  &mtk_msi_bottom_domain_ops, pcie);
666	if (!pcie->msi_bottom_domain) {
667		dev_err(dev, "failed to create MSI bottom domain\n");
668		ret = -ENODEV;
669		goto err_msi_bottom_domain;
670	}
671
672	pcie->msi_domain = pci_msi_create_irq_domain(dev->fwnode,
673						     &mtk_msi_domain_info,
674						     pcie->msi_bottom_domain);
675	if (!pcie->msi_domain) {
676		dev_err(dev, "failed to create MSI domain\n");
677		ret = -ENODEV;
678		goto err_msi_domain;
679	}
680
681	of_node_put(intc_node);
682	return 0;
683
684err_msi_domain:
685	irq_domain_remove(pcie->msi_bottom_domain);
686err_msi_bottom_domain:
687	irq_domain_remove(pcie->intx_domain);
688out_put_node:
689	of_node_put(intc_node);
690	return ret;
691}
692
693static void mtk_pcie_irq_teardown(struct mtk_gen3_pcie *pcie)
694{
695	irq_set_chained_handler_and_data(pcie->irq, NULL, NULL);
696
697	if (pcie->intx_domain)
698		irq_domain_remove(pcie->intx_domain);
699
700	if (pcie->msi_domain)
701		irq_domain_remove(pcie->msi_domain);
702
703	if (pcie->msi_bottom_domain)
704		irq_domain_remove(pcie->msi_bottom_domain);
705
706	irq_dispose_mapping(pcie->irq);
707}
708
709static void mtk_pcie_msi_handler(struct mtk_gen3_pcie *pcie, int set_idx)
710{
711	struct mtk_msi_set *msi_set = &pcie->msi_sets[set_idx];
712	unsigned long msi_enable, msi_status;
713	irq_hw_number_t bit, hwirq;
714
715	msi_enable = readl_relaxed(msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
716
717	do {
718		msi_status = readl_relaxed(msi_set->base +
719					   PCIE_MSI_SET_STATUS_OFFSET);
720		msi_status &= msi_enable;
721		if (!msi_status)
722			break;
723
724		for_each_set_bit(bit, &msi_status, PCIE_MSI_IRQS_PER_SET) {
725			hwirq = bit + set_idx * PCIE_MSI_IRQS_PER_SET;
726			generic_handle_domain_irq(pcie->msi_bottom_domain, hwirq);
727		}
728	} while (true);
729}
730
731static void mtk_pcie_irq_handler(struct irq_desc *desc)
732{
733	struct mtk_gen3_pcie *pcie = irq_desc_get_handler_data(desc);
734	struct irq_chip *irqchip = irq_desc_get_chip(desc);
735	unsigned long status;
736	irq_hw_number_t irq_bit = PCIE_INTX_SHIFT;
737
738	chained_irq_enter(irqchip, desc);
739
740	status = readl_relaxed(pcie->base + PCIE_INT_STATUS_REG);
741	for_each_set_bit_from(irq_bit, &status, PCI_NUM_INTX +
742			      PCIE_INTX_SHIFT)
743		generic_handle_domain_irq(pcie->intx_domain,
744					  irq_bit - PCIE_INTX_SHIFT);
745
746	irq_bit = PCIE_MSI_SHIFT;
747	for_each_set_bit_from(irq_bit, &status, PCIE_MSI_SET_NUM +
748			      PCIE_MSI_SHIFT) {
749		mtk_pcie_msi_handler(pcie, irq_bit - PCIE_MSI_SHIFT);
750
751		writel_relaxed(BIT(irq_bit), pcie->base + PCIE_INT_STATUS_REG);
752	}
753
754	chained_irq_exit(irqchip, desc);
755}
756
757static int mtk_pcie_setup_irq(struct mtk_gen3_pcie *pcie)
758{
759	struct device *dev = pcie->dev;
760	struct platform_device *pdev = to_platform_device(dev);
761	int err;
762
763	err = mtk_pcie_init_irq_domains(pcie);
764	if (err)
765		return err;
766
767	pcie->irq = platform_get_irq(pdev, 0);
768	if (pcie->irq < 0)
769		return pcie->irq;
770
771	irq_set_chained_handler_and_data(pcie->irq, mtk_pcie_irq_handler, pcie);
772
773	return 0;
774}
775
776static int mtk_pcie_parse_port(struct mtk_gen3_pcie *pcie)
777{
778	struct device *dev = pcie->dev;
779	struct platform_device *pdev = to_platform_device(dev);
780	struct resource *regs;
781	int ret;
782
783	regs = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcie-mac");
784	if (!regs)
785		return -EINVAL;
786	pcie->base = devm_ioremap_resource(dev, regs);
787	if (IS_ERR(pcie->base)) {
788		dev_err(dev, "failed to map register base\n");
789		return PTR_ERR(pcie->base);
790	}
791
792	pcie->reg_base = regs->start;
793
794	pcie->phy_reset = devm_reset_control_get_optional_exclusive(dev, "phy");
795	if (IS_ERR(pcie->phy_reset)) {
796		ret = PTR_ERR(pcie->phy_reset);
797		if (ret != -EPROBE_DEFER)
798			dev_err(dev, "failed to get PHY reset\n");
799
800		return ret;
801	}
802
803	pcie->mac_reset = devm_reset_control_get_optional_exclusive(dev, "mac");
804	if (IS_ERR(pcie->mac_reset)) {
805		ret = PTR_ERR(pcie->mac_reset);
806		if (ret != -EPROBE_DEFER)
807			dev_err(dev, "failed to get MAC reset\n");
808
809		return ret;
810	}
811
812	pcie->phy = devm_phy_optional_get(dev, "pcie-phy");
813	if (IS_ERR(pcie->phy)) {
814		ret = PTR_ERR(pcie->phy);
815		if (ret != -EPROBE_DEFER)
816			dev_err(dev, "failed to get PHY\n");
817
818		return ret;
819	}
820
821	pcie->num_clks = devm_clk_bulk_get_all(dev, &pcie->clks);
822	if (pcie->num_clks < 0) {
823		dev_err(dev, "failed to get clocks\n");
824		return pcie->num_clks;
825	}
826
827	return 0;
828}
829
830static int mtk_pcie_power_up(struct mtk_gen3_pcie *pcie)
831{
832	struct device *dev = pcie->dev;
833	int err;
834
835	/* PHY power on and enable pipe clock */
836	reset_control_deassert(pcie->phy_reset);
837
838	err = phy_init(pcie->phy);
839	if (err) {
840		dev_err(dev, "failed to initialize PHY\n");
841		goto err_phy_init;
842	}
843
844	err = phy_power_on(pcie->phy);
845	if (err) {
846		dev_err(dev, "failed to power on PHY\n");
847		goto err_phy_on;
848	}
849
850	/* MAC power on and enable transaction layer clocks */
851	reset_control_deassert(pcie->mac_reset);
852
853	pm_runtime_enable(dev);
854	pm_runtime_get_sync(dev);
855
856	err = clk_bulk_prepare_enable(pcie->num_clks, pcie->clks);
857	if (err) {
858		dev_err(dev, "failed to enable clocks\n");
859		goto err_clk_init;
860	}
861
862	return 0;
863
864err_clk_init:
865	pm_runtime_put_sync(dev);
866	pm_runtime_disable(dev);
867	reset_control_assert(pcie->mac_reset);
868	phy_power_off(pcie->phy);
869err_phy_on:
870	phy_exit(pcie->phy);
871err_phy_init:
872	reset_control_assert(pcie->phy_reset);
873
874	return err;
875}
876
877static void mtk_pcie_power_down(struct mtk_gen3_pcie *pcie)
878{
879	clk_bulk_disable_unprepare(pcie->num_clks, pcie->clks);
880
881	pm_runtime_put_sync(pcie->dev);
882	pm_runtime_disable(pcie->dev);
883	reset_control_assert(pcie->mac_reset);
884
885	phy_power_off(pcie->phy);
886	phy_exit(pcie->phy);
887	reset_control_assert(pcie->phy_reset);
888}
889
890static int mtk_pcie_setup(struct mtk_gen3_pcie *pcie)
891{
892	int err;
893
894	err = mtk_pcie_parse_port(pcie);
895	if (err)
896		return err;
897
898	/*
899	 * The controller may have been left out of reset by the bootloader
900	 * so make sure that we get a clean start by asserting resets here.
901	 */
902	reset_control_assert(pcie->phy_reset);
903	reset_control_assert(pcie->mac_reset);
904	usleep_range(10, 20);
905
906	/* Don't touch the hardware registers before power up */
907	err = mtk_pcie_power_up(pcie);
908	if (err)
909		return err;
910
911	/* Try link up */
912	err = mtk_pcie_startup_port(pcie);
913	if (err)
914		goto err_setup;
915
916	err = mtk_pcie_setup_irq(pcie);
917	if (err)
918		goto err_setup;
919
920	return 0;
921
922err_setup:
923	mtk_pcie_power_down(pcie);
924
925	return err;
926}
927
928static int mtk_pcie_probe(struct platform_device *pdev)
929{
930	struct device *dev = &pdev->dev;
931	struct mtk_gen3_pcie *pcie;
932	struct pci_host_bridge *host;
933	int err;
934
935	host = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
936	if (!host)
937		return -ENOMEM;
938
939	pcie = pci_host_bridge_priv(host);
940
941	pcie->dev = dev;
942	platform_set_drvdata(pdev, pcie);
943
944	err = mtk_pcie_setup(pcie);
945	if (err)
946		return err;
947
948	host->ops = &mtk_pcie_ops;
949	host->sysdata = pcie;
950
951	err = pci_host_probe(host);
952	if (err) {
953		mtk_pcie_irq_teardown(pcie);
954		mtk_pcie_power_down(pcie);
955		return err;
956	}
957
958	return 0;
959}
960
961static void mtk_pcie_remove(struct platform_device *pdev)
962{
963	struct mtk_gen3_pcie *pcie = platform_get_drvdata(pdev);
964	struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
965
966	pci_lock_rescan_remove();
967	pci_stop_root_bus(host->bus);
968	pci_remove_root_bus(host->bus);
969	pci_unlock_rescan_remove();
970
971	mtk_pcie_irq_teardown(pcie);
972	mtk_pcie_power_down(pcie);
973}
974
975static void mtk_pcie_irq_save(struct mtk_gen3_pcie *pcie)
976{
977	int i;
978
979	raw_spin_lock(&pcie->irq_lock);
980
981	pcie->saved_irq_state = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
982
983	for (i = 0; i < PCIE_MSI_SET_NUM; i++) {
984		struct mtk_msi_set *msi_set = &pcie->msi_sets[i];
985
986		msi_set->saved_irq_state = readl_relaxed(msi_set->base +
987					   PCIE_MSI_SET_ENABLE_OFFSET);
988	}
989
990	raw_spin_unlock(&pcie->irq_lock);
991}
992
993static void mtk_pcie_irq_restore(struct mtk_gen3_pcie *pcie)
994{
995	int i;
996
997	raw_spin_lock(&pcie->irq_lock);
998
999	writel_relaxed(pcie->saved_irq_state, pcie->base + PCIE_INT_ENABLE_REG);
1000
1001	for (i = 0; i < PCIE_MSI_SET_NUM; i++) {
1002		struct mtk_msi_set *msi_set = &pcie->msi_sets[i];
1003
1004		writel_relaxed(msi_set->saved_irq_state,
1005			       msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
1006	}
1007
1008	raw_spin_unlock(&pcie->irq_lock);
1009}
1010
1011static int mtk_pcie_turn_off_link(struct mtk_gen3_pcie *pcie)
1012{
1013	u32 val;
1014
1015	val = readl_relaxed(pcie->base + PCIE_ICMD_PM_REG);
1016	val |= PCIE_TURN_OFF_LINK;
1017	writel_relaxed(val, pcie->base + PCIE_ICMD_PM_REG);
1018
1019	/* Check the link is L2 */
1020	return readl_poll_timeout(pcie->base + PCIE_LTSSM_STATUS_REG, val,
1021				  (PCIE_LTSSM_STATE(val) ==
1022				   PCIE_LTSSM_STATE_L2_IDLE), 20,
1023				   50 * USEC_PER_MSEC);
1024}
1025
1026static int mtk_pcie_suspend_noirq(struct device *dev)
1027{
1028	struct mtk_gen3_pcie *pcie = dev_get_drvdata(dev);
1029	int err;
1030	u32 val;
1031
1032	/* Trigger link to L2 state */
1033	err = mtk_pcie_turn_off_link(pcie);
1034	if (err) {
1035		dev_err(pcie->dev, "cannot enter L2 state\n");
1036		return err;
1037	}
1038
1039	/* Pull down the PERST# pin */
1040	val = readl_relaxed(pcie->base + PCIE_RST_CTRL_REG);
1041	val |= PCIE_PE_RSTB;
1042	writel_relaxed(val, pcie->base + PCIE_RST_CTRL_REG);
1043
1044	dev_dbg(pcie->dev, "entered L2 states successfully");
1045
1046	mtk_pcie_irq_save(pcie);
1047	mtk_pcie_power_down(pcie);
1048
1049	return 0;
1050}
1051
1052static int mtk_pcie_resume_noirq(struct device *dev)
1053{
1054	struct mtk_gen3_pcie *pcie = dev_get_drvdata(dev);
1055	int err;
1056
1057	err = mtk_pcie_power_up(pcie);
1058	if (err)
1059		return err;
1060
1061	err = mtk_pcie_startup_port(pcie);
1062	if (err) {
1063		mtk_pcie_power_down(pcie);
1064		return err;
1065	}
1066
1067	mtk_pcie_irq_restore(pcie);
1068
1069	return 0;
1070}
1071
1072static const struct dev_pm_ops mtk_pcie_pm_ops = {
1073	NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_pcie_suspend_noirq,
1074				  mtk_pcie_resume_noirq)
1075};
1076
1077static const struct of_device_id mtk_pcie_of_match[] = {
1078	{ .compatible = "mediatek,mt8192-pcie" },
1079	{},
1080};
1081MODULE_DEVICE_TABLE(of, mtk_pcie_of_match);
1082
1083static struct platform_driver mtk_pcie_driver = {
1084	.probe = mtk_pcie_probe,
1085	.remove_new = mtk_pcie_remove,
1086	.driver = {
1087		.name = "mtk-pcie-gen3",
1088		.of_match_table = mtk_pcie_of_match,
1089		.pm = &mtk_pcie_pm_ops,
1090	},
1091};
1092
1093module_platform_driver(mtk_pcie_driver);
1094MODULE_LICENSE("GPL v2");
1095