xref: /linux/drivers/pci/controller/pcie-mediatek-gen3.c (revision fab183d632628381b466a41479489541ac0e29a0)
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/bitfield.h>
10 #include <linux/clk.h>
11 #include <linux/clk-provider.h>
12 #include <linux/delay.h>
13 #include <linux/iopoll.h>
14 #include <linux/irq.h>
15 #include <linux/irqchip/irq-msi-lib.h>
16 #include <linux/irqchip/chained_irq.h>
17 #include <linux/irqdomain.h>
18 #include <linux/kernel.h>
19 #include <linux/mfd/syscon.h>
20 #include <linux/module.h>
21 #include <linux/msi.h>
22 #include <linux/of_device.h>
23 #include <linux/of_pci.h>
24 #include <linux/pci.h>
25 #include <linux/pci-pwrctrl.h>
26 #include <linux/phy/phy.h>
27 #include <linux/platform_device.h>
28 #include <linux/pm_domain.h>
29 #include <linux/pm_runtime.h>
30 #include <linux/regmap.h>
31 #include <linux/reset.h>
32 
33 #include "pci-host-common.h"
34 #include "../pci.h"
35 
36 #define PCIE_BASE_CFG_REG		0x14
37 #define PCIE_BASE_CFG_SPEED		GENMASK(15, 8)
38 
39 #define PCIE_SETTING_REG		0x80
40 #define PCIE_SETTING_LINK_WIDTH		GENMASK(11, 8)
41 #define PCIE_SETTING_GEN_SUPPORT	GENMASK(14, 12)
42 #define PCIE_PCI_IDS_1			0x9c
43 #define PCI_CLASS(class)		(class << 8)
44 #define PCIE_RC_MODE			BIT(0)
45 
46 #define PCIE_EQ_PRESET_01_REG		0x100
47 #define PCIE_VAL_LN0_DOWNSTREAM		GENMASK(6, 0)
48 #define PCIE_VAL_LN0_UPSTREAM		GENMASK(14, 8)
49 #define PCIE_VAL_LN1_DOWNSTREAM		GENMASK(22, 16)
50 #define PCIE_VAL_LN1_UPSTREAM		GENMASK(30, 24)
51 
52 #define PCIE_CFGNUM_REG			0x140
53 #define PCIE_CFG_DEVFN(devfn)		((devfn) & GENMASK(7, 0))
54 #define PCIE_CFG_BUS(bus)		(((bus) << 8) & GENMASK(15, 8))
55 #define PCIE_CFG_BYTE_EN(bytes)		(((bytes) << 16) & GENMASK(19, 16))
56 #define PCIE_CFG_FORCE_BYTE_EN		BIT(20)
57 #define PCIE_CFG_OFFSET_ADDR		0x1000
58 #define PCIE_CFG_HEADER(bus, devfn) \
59 	(PCIE_CFG_BUS(bus) | PCIE_CFG_DEVFN(devfn))
60 
61 #define PCIE_RST_CTRL_REG		0x148
62 #define PCIE_MAC_RSTB			BIT(0)
63 #define PCIE_PHY_RSTB			BIT(1)
64 #define PCIE_BRG_RSTB			BIT(2)
65 #define PCIE_PE_RSTB			BIT(3)
66 
67 /*
68  * As described in the datasheet of MediaTek PCIe Gen3 controller, wait 10ms
69  * after setting PCIE_BRG_RSTB, and before accessing PCIe internal registers.
70  */
71 #define PCIE_BRG_RST_RDY_MS		10
72 
73 #define PCIE_LTSSM_STATUS_REG		0x150
74 #define PCIE_LTSSM_STATE_MASK		GENMASK(28, 24)
75 #define PCIE_LTSSM_STATE(val)		((val & PCIE_LTSSM_STATE_MASK) >> 24)
76 #define PCIE_LTSSM_STATE_L2_IDLE	0x14
77 
78 #define PCIE_LINK_STATUS_REG		0x154
79 #define PCIE_PORT_LINKUP		BIT(8)
80 
81 #define PCIE_MSI_SET_NUM		8
82 #define PCIE_MSI_IRQS_PER_SET		32
83 #define PCIE_MSI_IRQS_NUM \
84 	(PCIE_MSI_IRQS_PER_SET * PCIE_MSI_SET_NUM)
85 
86 #define PCIE_INT_ENABLE_REG		0x180
87 #define PCIE_MSI_ENABLE			GENMASK(PCIE_MSI_SET_NUM + 8 - 1, 8)
88 #define PCIE_MSI_SHIFT			8
89 #define PCIE_INTX_SHIFT			24
90 #define PCIE_INTX_ENABLE \
91 	GENMASK(PCIE_INTX_SHIFT + PCI_NUM_INTX - 1, PCIE_INTX_SHIFT)
92 
93 #define PCIE_INT_STATUS_REG		0x184
94 #define PCIE_MSI_SET_ENABLE_REG		0x190
95 #define PCIE_MSI_SET_ENABLE		GENMASK(PCIE_MSI_SET_NUM - 1, 0)
96 
97 #define PCIE_PIPE4_PIE8_REG		0x338
98 #define PCIE_K_FINETUNE_MAX		GENMASK(5, 0)
99 #define PCIE_K_FINETUNE_ERR		GENMASK(7, 6)
100 #define PCIE_K_PRESET_TO_USE		GENMASK(18, 8)
101 #define PCIE_K_PHYPARAM_QUERY		BIT(19)
102 #define PCIE_K_QUERY_TIMEOUT		BIT(20)
103 #define PCIE_K_PRESET_TO_USE_16G	GENMASK(31, 21)
104 
105 #define PCIE_MSI_SET_BASE_REG		0xc00
106 #define PCIE_MSI_SET_OFFSET		0x10
107 #define PCIE_MSI_SET_STATUS_OFFSET	0x04
108 #define PCIE_MSI_SET_ENABLE_OFFSET	0x08
109 
110 #define PCIE_MSI_SET_ADDR_HI_BASE	0xc80
111 #define PCIE_MSI_SET_ADDR_HI_OFFSET	0x04
112 
113 #define PCIE_RESOURCE_CTRL_REG		0xd2c
114 #define PCIE_RSRC_SYS_CLK_RDY_TIME_MASK	GENMASK(7, 0)
115 
116 #define PCIE_ICMD_PM_REG		0x198
117 #define PCIE_TURN_OFF_LINK		BIT(4)
118 
119 #define PCIE_MISC_CTRL_REG		0x348
120 #define PCIE_DISABLE_DVFSRC_VLT_REQ	BIT(1)
121 
122 #define PCIE_TRANS_TABLE_BASE_REG	0x800
123 #define PCIE_ATR_SRC_ADDR_MSB_OFFSET	0x4
124 #define PCIE_ATR_TRSL_ADDR_LSB_OFFSET	0x8
125 #define PCIE_ATR_TRSL_ADDR_MSB_OFFSET	0xc
126 #define PCIE_ATR_TRSL_PARAM_OFFSET	0x10
127 #define PCIE_ATR_TLB_SET_OFFSET		0x20
128 
129 #define PCIE_MAX_TRANS_TABLES		8
130 #define PCIE_ATR_EN			BIT(0)
131 #define PCIE_ATR_SIZE(size) \
132 	(((((size) - 1) << 1) & GENMASK(6, 1)) | PCIE_ATR_EN)
133 #define PCIE_ATR_ID(id)			((id) & GENMASK(3, 0))
134 #define PCIE_ATR_TYPE_MEM		PCIE_ATR_ID(0)
135 #define PCIE_ATR_TYPE_IO		PCIE_ATR_ID(1)
136 #define PCIE_ATR_TLP_TYPE(type)		(((type) << 16) & GENMASK(18, 16))
137 #define PCIE_ATR_TLP_TYPE_MEM		PCIE_ATR_TLP_TYPE(0)
138 #define PCIE_ATR_TLP_TYPE_IO		PCIE_ATR_TLP_TYPE(2)
139 
140 #define MAX_NUM_PHY_RESETS		3
141 
142 #define PCIE_MTK_RESET_TIME_US		10
143 
144 /* Time in ms needed to complete PCIe reset on EN7581 SoC */
145 #define PCIE_EN7581_RESET_TIME_MS	100
146 
147 struct mtk_gen3_pcie;
148 
149 #define PCIE_CONF_LINK2_CTL_STS		(PCIE_CFG_OFFSET_ADDR + 0xb0)
150 #define PCIE_CONF_LINK2_LCR2_LINK_SPEED	GENMASK(3, 0)
151 
152 enum mtk_gen3_pcie_flags {
153 	SKIP_PCIE_RSTB	= BIT(0), /* Skip PERST# assertion during device
154 				   * probing or suspend/resume phase to
155 				   * avoid hw bugs/issues.
156 				   */
157 };
158 
159 /**
160  * struct mtk_gen3_pcie_pdata - differentiate between host generations
161  * @power_up: pcie power_up callback
162  * @phy_resets: phy reset lines SoC data.
163  * @sys_clk_rdy_time_us: System clock ready time override (microseconds)
164  * @flags: pcie device flags.
165  */
166 struct mtk_gen3_pcie_pdata {
167 	int (*power_up)(struct mtk_gen3_pcie *pcie);
168 	struct {
169 		const char *id[MAX_NUM_PHY_RESETS];
170 		int num_resets;
171 	} phy_resets;
172 	u8 sys_clk_rdy_time_us;
173 	u32 flags;
174 };
175 
176 /**
177  * struct mtk_msi_set - MSI information for each set
178  * @base: IO mapped register base
179  * @msg_addr: MSI message address
180  * @saved_irq_state: IRQ enable state saved at suspend time
181  */
182 struct mtk_msi_set {
183 	void __iomem *base;
184 	phys_addr_t msg_addr;
185 	u32 saved_irq_state;
186 };
187 
188 /**
189  * struct mtk_gen3_pcie - PCIe port information
190  * @dev: pointer to PCIe device
191  * @base: IO mapped register base
192  * @reg_base: physical register base
193  * @mac_reset: MAC reset control
194  * @phy_resets: PHY reset controllers
195  * @phy: PHY controller block
196  * @clks: PCIe clocks
197  * @num_clks: PCIe clocks count for this port
198  * @max_link_speed: Maximum link speed (PCIe Gen) for this port
199  * @num_lanes: Number of PCIe lanes for this port
200  * @irq: PCIe controller interrupt number
201  * @saved_irq_state: IRQ enable state saved at suspend time
202  * @irq_lock: lock protecting IRQ register access
203  * @intx_domain: legacy INTx IRQ domain
204  * @msi_bottom_domain: MSI IRQ bottom domain
205  * @msi_sets: MSI sets information
206  * @lock: lock protecting IRQ bit map
207  * @msi_irq_in_use: bit map for assigned MSI IRQ
208  * @soc: pointer to SoC-dependent operations
209  */
210 struct mtk_gen3_pcie {
211 	struct device *dev;
212 	void __iomem *base;
213 	phys_addr_t reg_base;
214 	struct reset_control *mac_reset;
215 	struct reset_control_bulk_data phy_resets[MAX_NUM_PHY_RESETS];
216 	struct phy *phy;
217 	struct clk_bulk_data *clks;
218 	int num_clks;
219 	u8 max_link_speed;
220 	u8 num_lanes;
221 
222 	int irq;
223 	u32 saved_irq_state;
224 	raw_spinlock_t irq_lock;
225 	struct irq_domain *intx_domain;
226 	struct irq_domain *msi_bottom_domain;
227 	struct mtk_msi_set msi_sets[PCIE_MSI_SET_NUM];
228 	struct mutex lock;
229 	DECLARE_BITMAP(msi_irq_in_use, PCIE_MSI_IRQS_NUM);
230 
231 	const struct mtk_gen3_pcie_pdata *soc;
232 };
233 
234 /* LTSSM state in PCIE_LTSSM_STATUS_REG bit[28:24] */
235 static const char *const ltssm_str[] = {
236 	"detect.quiet",			/* 0x00 */
237 	"detect.active",		/* 0x01 */
238 	"polling.active",		/* 0x02 */
239 	"polling.compliance",		/* 0x03 */
240 	"polling.configuration",	/* 0x04 */
241 	"config.linkwidthstart",	/* 0x05 */
242 	"config.linkwidthaccept",	/* 0x06 */
243 	"config.lanenumwait",		/* 0x07 */
244 	"config.lanenumaccept",		/* 0x08 */
245 	"config.complete",		/* 0x09 */
246 	"config.idle",			/* 0x0A */
247 	"recovery.receiverlock",	/* 0x0B */
248 	"recovery.equalization",	/* 0x0C */
249 	"recovery.speed",		/* 0x0D */
250 	"recovery.receiverconfig",	/* 0x0E */
251 	"recovery.idle",		/* 0x0F */
252 	"L0",				/* 0x10 */
253 	"L0s",				/* 0x11 */
254 	"L1.entry",			/* 0x12 */
255 	"L1.idle",			/* 0x13 */
256 	"L2.idle",			/* 0x14 */
257 	"L2.transmitwake",		/* 0x15 */
258 	"disable",			/* 0x16 */
259 	"loopback.entry",		/* 0x17 */
260 	"loopback.active",		/* 0x18 */
261 	"loopback.exit",		/* 0x19 */
262 	"hotreset",			/* 0x1A */
263 };
264 
265 /**
266  * mtk_pcie_config_tlp_header() - Configure a configuration TLP header
267  * @bus: PCI bus to query
268  * @devfn: device/function number
269  * @where: offset in config space
270  * @size: data size in TLP header
271  *
272  * Set byte enable field and device information in configuration TLP header.
273  */
mtk_pcie_config_tlp_header(struct pci_bus * bus,unsigned int devfn,int where,int size)274 static void mtk_pcie_config_tlp_header(struct pci_bus *bus, unsigned int devfn,
275 					int where, int size)
276 {
277 	struct mtk_gen3_pcie *pcie = bus->sysdata;
278 	int bytes;
279 	u32 val;
280 
281 	bytes = (GENMASK(size - 1, 0) & 0xf) << (where & 0x3);
282 
283 	val = PCIE_CFG_FORCE_BYTE_EN | PCIE_CFG_BYTE_EN(bytes) |
284 	      PCIE_CFG_HEADER(bus->number, devfn);
285 
286 	writel_relaxed(val, pcie->base + PCIE_CFGNUM_REG);
287 }
288 
mtk_pcie_map_bus(struct pci_bus * bus,unsigned int devfn,int where)289 static void __iomem *mtk_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
290 				      int where)
291 {
292 	struct mtk_gen3_pcie *pcie = bus->sysdata;
293 
294 	return pcie->base + PCIE_CFG_OFFSET_ADDR + where;
295 }
296 
mtk_pcie_config_read(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * val)297 static int mtk_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
298 				int where, int size, u32 *val)
299 {
300 	mtk_pcie_config_tlp_header(bus, devfn, where, size);
301 
302 	return pci_generic_config_read32(bus, devfn, where, size, val);
303 }
304 
mtk_pcie_config_write(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 val)305 static int mtk_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
306 				 int where, int size, u32 val)
307 {
308 	mtk_pcie_config_tlp_header(bus, devfn, where, size);
309 
310 	if (size <= 2)
311 		val <<= (where & 0x3) * 8;
312 
313 	return pci_generic_config_write32(bus, devfn, where, 4, val);
314 }
315 
316 static struct pci_ops mtk_pcie_ops = {
317 	.map_bus = mtk_pcie_map_bus,
318 	.read  = mtk_pcie_config_read,
319 	.write = mtk_pcie_config_write,
320 };
321 
mtk_pcie_set_trans_table(struct mtk_gen3_pcie * pcie,resource_size_t cpu_addr,resource_size_t pci_addr,resource_size_t size,unsigned long type,int * num)322 static int mtk_pcie_set_trans_table(struct mtk_gen3_pcie *pcie,
323 				    resource_size_t cpu_addr,
324 				    resource_size_t pci_addr,
325 				    resource_size_t size,
326 				    unsigned long type, int *num)
327 {
328 	resource_size_t remaining = size;
329 	resource_size_t table_size;
330 	resource_size_t addr_align;
331 	const char *range_type;
332 	void __iomem *table;
333 	u32 val;
334 
335 	while (remaining && (*num < PCIE_MAX_TRANS_TABLES)) {
336 		/* Table size needs to be a power of 2 */
337 		table_size = BIT(fls(remaining) - 1);
338 
339 		if (cpu_addr > 0) {
340 			addr_align = BIT(ffs(cpu_addr) - 1);
341 			table_size = min(table_size, addr_align);
342 		}
343 
344 		/* Minimum size of translate table is 4KiB */
345 		if (table_size < 0x1000) {
346 			dev_err(pcie->dev, "illegal table size %#llx\n",
347 				(unsigned long long)table_size);
348 			return -EINVAL;
349 		}
350 
351 		table = pcie->base + PCIE_TRANS_TABLE_BASE_REG + *num * PCIE_ATR_TLB_SET_OFFSET;
352 		writel_relaxed(lower_32_bits(cpu_addr) | PCIE_ATR_SIZE(fls(table_size) - 1), table);
353 		writel_relaxed(upper_32_bits(cpu_addr), table + PCIE_ATR_SRC_ADDR_MSB_OFFSET);
354 		writel_relaxed(lower_32_bits(pci_addr), table + PCIE_ATR_TRSL_ADDR_LSB_OFFSET);
355 		writel_relaxed(upper_32_bits(pci_addr), table + PCIE_ATR_TRSL_ADDR_MSB_OFFSET);
356 
357 		if (type == IORESOURCE_IO) {
358 			val = PCIE_ATR_TYPE_IO | PCIE_ATR_TLP_TYPE_IO;
359 			range_type = "IO";
360 		} else {
361 			val = PCIE_ATR_TYPE_MEM | PCIE_ATR_TLP_TYPE_MEM;
362 			range_type = "MEM";
363 		}
364 
365 		writel_relaxed(val, table + PCIE_ATR_TRSL_PARAM_OFFSET);
366 
367 		dev_dbg(pcie->dev, "set %s trans window[%d]: cpu_addr = %#llx, pci_addr = %#llx, size = %#llx\n",
368 			range_type, *num, (unsigned long long)cpu_addr,
369 			(unsigned long long)pci_addr,
370 			(unsigned long long)table_size);
371 
372 		cpu_addr += table_size;
373 		pci_addr += table_size;
374 		remaining -= table_size;
375 		(*num)++;
376 	}
377 
378 	if (remaining)
379 		dev_warn(pcie->dev, "not enough translate table for addr: %#llx, limited to [%d]\n",
380 			 (unsigned long long)cpu_addr, PCIE_MAX_TRANS_TABLES);
381 
382 	return 0;
383 }
384 
mtk_pcie_enable_msi(struct mtk_gen3_pcie * pcie)385 static void mtk_pcie_enable_msi(struct mtk_gen3_pcie *pcie)
386 {
387 	int i;
388 	u32 val;
389 
390 	for (i = 0; i < PCIE_MSI_SET_NUM; i++) {
391 		struct mtk_msi_set *msi_set = &pcie->msi_sets[i];
392 
393 		msi_set->base = pcie->base + PCIE_MSI_SET_BASE_REG +
394 				i * PCIE_MSI_SET_OFFSET;
395 		msi_set->msg_addr = pcie->reg_base + PCIE_MSI_SET_BASE_REG +
396 				    i * PCIE_MSI_SET_OFFSET;
397 
398 		/* Configure the MSI capture address */
399 		writel_relaxed(lower_32_bits(msi_set->msg_addr), msi_set->base);
400 		writel_relaxed(upper_32_bits(msi_set->msg_addr),
401 			       pcie->base + PCIE_MSI_SET_ADDR_HI_BASE +
402 			       i * PCIE_MSI_SET_ADDR_HI_OFFSET);
403 	}
404 
405 	val = readl_relaxed(pcie->base + PCIE_MSI_SET_ENABLE_REG);
406 	val |= PCIE_MSI_SET_ENABLE;
407 	writel_relaxed(val, pcie->base + PCIE_MSI_SET_ENABLE_REG);
408 
409 	val = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
410 	val |= PCIE_MSI_ENABLE;
411 	writel_relaxed(val, pcie->base + PCIE_INT_ENABLE_REG);
412 }
413 
mtk_pcie_devices_power_up(struct mtk_gen3_pcie * pcie)414 static int mtk_pcie_devices_power_up(struct mtk_gen3_pcie *pcie)
415 {
416 	int err;
417 	u32 val;
418 
419 	/*
420 	 * Airoha EN7581 has a hw bug asserting/releasing PCIE_PE_RSTB signal
421 	 * causing occasional PCIe link down. In order to overcome the issue,
422 	 * PCIE_RSTB signals are not asserted/released at this stage and the
423 	 * PCIe block is reset using en7523_reset_assert() and
424 	 * en7581_pci_enable().
425 	 */
426 	if (!(pcie->soc->flags & SKIP_PCIE_RSTB)) {
427 		/* Assert all reset signals */
428 		val = readl_relaxed(pcie->base + PCIE_RST_CTRL_REG);
429 		val |= PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB |
430 		       PCIE_PE_RSTB;
431 		writel_relaxed(val, pcie->base + PCIE_RST_CTRL_REG);
432 	}
433 
434 	err = pci_pwrctrl_power_on_devices(pcie->dev);
435 	if (err) {
436 		dev_err(pcie->dev, "Failed to power on devices: %pe\n", ERR_PTR(err));
437 		return err;
438 	}
439 
440 	/*
441 	 * Some of MediaTek's chips won't output REFCLK when PCIE_PHY_RSTB is
442 	 * asserted, we have to de-assert MAC & PHY & BRG reset signals first
443 	 * to allow the REFCLK to be stable. While PCIE_BRG_RSTB is asserted,
444 	 * there is a short period during which the PCIe internal register
445 	 * cannot be accessed, so we need to wait 10ms here.
446 	 */
447 	msleep(PCIE_BRG_RST_RDY_MS);
448 
449 	if (!(pcie->soc->flags & SKIP_PCIE_RSTB)) {
450 		/* De-assert MAC, PHY and BRG reset signals */
451 		val &= ~(PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB);
452 		writel_relaxed(val, pcie->base + PCIE_RST_CTRL_REG);
453 	}
454 
455 	/*
456 	 * Described in PCIe CEM specification revision 6.0.
457 	 *
458 	 * The deassertion of PERST# should be delayed 100ms (TPVPERL)
459 	 * for the power and clock to become stable.
460 	 */
461 	msleep(PCIE_T_PVPERL_MS);
462 
463 	if (!(pcie->soc->flags & SKIP_PCIE_RSTB)) {
464 		/* De-assert PERST# signal */
465 		val &= ~PCIE_PE_RSTB;
466 		writel_relaxed(val, pcie->base + PCIE_RST_CTRL_REG);
467 	}
468 
469 	return 0;
470 }
471 
mtk_pcie_devices_power_down(struct mtk_gen3_pcie * pcie)472 static void mtk_pcie_devices_power_down(struct mtk_gen3_pcie *pcie)
473 {
474 	u32 val;
475 
476 	if (!(pcie->soc->flags & SKIP_PCIE_RSTB)) {
477 		/* Assert the PERST# pin */
478 		val = readl_relaxed(pcie->base + PCIE_RST_CTRL_REG);
479 		val |= PCIE_PE_RSTB;
480 		writel_relaxed(val, pcie->base + PCIE_RST_CTRL_REG);
481 	}
482 
483 	pci_pwrctrl_power_off_devices(pcie->dev);
484 }
485 
mtk_pcie_startup_port(struct mtk_gen3_pcie * pcie)486 static int mtk_pcie_startup_port(struct mtk_gen3_pcie *pcie)
487 {
488 	struct resource_entry *entry;
489 	struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
490 	unsigned int table_index = 0;
491 	int err;
492 	u32 val;
493 
494 	/* Set as RC mode and set controller PCIe Gen speed restriction, if any */
495 	val = readl_relaxed(pcie->base + PCIE_SETTING_REG);
496 	val |= PCIE_RC_MODE;
497 	if (pcie->max_link_speed) {
498 		val &= ~PCIE_SETTING_GEN_SUPPORT;
499 
500 		/* Can enable link speed support only from Gen2 onwards */
501 		if (pcie->max_link_speed >= 2)
502 			val |= FIELD_PREP(PCIE_SETTING_GEN_SUPPORT,
503 					  GENMASK(pcie->max_link_speed - 2, 0));
504 	}
505 	if (pcie->num_lanes) {
506 		val &= ~PCIE_SETTING_LINK_WIDTH;
507 
508 		/* Zero means one lane, each bit activates x2/x4/x8/x16 */
509 		if (pcie->num_lanes > 1)
510 			val |= FIELD_PREP(PCIE_SETTING_LINK_WIDTH,
511 					  GENMASK(fls(pcie->num_lanes >> 2), 0));
512 	}
513 	writel_relaxed(val, pcie->base + PCIE_SETTING_REG);
514 
515 	/* Set Link Control 2 (LNKCTL2) speed restriction, if any */
516 	if (pcie->max_link_speed) {
517 		val = readl_relaxed(pcie->base + PCIE_CONF_LINK2_CTL_STS);
518 		FIELD_MODIFY(PCIE_CONF_LINK2_LCR2_LINK_SPEED, &val, pcie->max_link_speed);
519 		writel_relaxed(val, pcie->base + PCIE_CONF_LINK2_CTL_STS);
520 	}
521 
522 	/* If parameter is present, adjust SYS_CLK_RDY_TIME to avoid glitching */
523 	if (pcie->soc->sys_clk_rdy_time_us) {
524 		val = readl_relaxed(pcie->base + PCIE_RESOURCE_CTRL_REG);
525 		FIELD_MODIFY(PCIE_RSRC_SYS_CLK_RDY_TIME_MASK, &val,
526 			     pcie->soc->sys_clk_rdy_time_us);
527 		writel_relaxed(val, pcie->base + PCIE_RESOURCE_CTRL_REG);
528 	}
529 
530 	/* Set class code */
531 	val = readl_relaxed(pcie->base + PCIE_PCI_IDS_1);
532 	val &= ~GENMASK(31, 8);
533 	val |= PCI_CLASS(PCI_CLASS_BRIDGE_PCI_NORMAL);
534 	writel_relaxed(val, pcie->base + PCIE_PCI_IDS_1);
535 
536 	/* Mask all INTx interrupts */
537 	val = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
538 	val &= ~PCIE_INTX_ENABLE;
539 	writel_relaxed(val, pcie->base + PCIE_INT_ENABLE_REG);
540 
541 	/* Disable DVFSRC voltage request */
542 	val = readl_relaxed(pcie->base + PCIE_MISC_CTRL_REG);
543 	val |= PCIE_DISABLE_DVFSRC_VLT_REQ;
544 	writel_relaxed(val, pcie->base + PCIE_MISC_CTRL_REG);
545 
546 	mtk_pcie_enable_msi(pcie);
547 
548 	/* Set PCIe translation windows */
549 	resource_list_for_each_entry(entry, &host->windows) {
550 		struct resource *res = entry->res;
551 		unsigned long type = resource_type(res);
552 		resource_size_t cpu_addr;
553 		resource_size_t pci_addr;
554 		resource_size_t size;
555 
556 		if (type == IORESOURCE_IO)
557 			cpu_addr = pci_pio_to_address(res->start);
558 		else if (type == IORESOURCE_MEM)
559 			cpu_addr = res->start;
560 		else
561 			continue;
562 
563 		pci_addr = res->start - entry->offset;
564 		size = resource_size(res);
565 		err = mtk_pcie_set_trans_table(pcie, cpu_addr, pci_addr, size,
566 					       type, &table_index);
567 		if (err)
568 			return err;
569 	}
570 
571 	err = mtk_pcie_devices_power_up(pcie);
572 	if (err)
573 		return err;
574 
575 	/* Check if the link is up or not */
576 	err = readl_poll_timeout(pcie->base + PCIE_LINK_STATUS_REG, val,
577 				 !!(val & PCIE_PORT_LINKUP), 20,
578 				 PCI_PM_D3COLD_WAIT * USEC_PER_MSEC);
579 	if (err) {
580 		const char *ltssm_state;
581 		int ltssm_index;
582 
583 		val = readl_relaxed(pcie->base + PCIE_LTSSM_STATUS_REG);
584 		ltssm_index = PCIE_LTSSM_STATE(val);
585 		ltssm_state = ltssm_index >= ARRAY_SIZE(ltssm_str) ?
586 			      "Unknown state" : ltssm_str[ltssm_index];
587 		dev_err(pcie->dev,
588 			"PCIe link down, current LTSSM state: %s (%#x)\n",
589 			ltssm_state, val);
590 		goto err_power_down_device;
591 	}
592 
593 	pci_host_common_link_train_delay(pcie->max_link_speed);
594 
595 	return 0;
596 
597 err_power_down_device:
598 	mtk_pcie_devices_power_down(pcie);
599 	return err;
600 }
601 
602 #define MTK_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
603 				MSI_FLAG_USE_DEF_CHIP_OPS	| \
604 				MSI_FLAG_NO_AFFINITY		| \
605 				MSI_FLAG_PCI_MSI_MASK_PARENT)
606 
607 #define MTK_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK		| \
608 				 MSI_FLAG_PCI_MSIX		| \
609 				 MSI_FLAG_MULTI_PCI_MSI)
610 
611 static const struct msi_parent_ops mtk_msi_parent_ops = {
612 	.required_flags		= MTK_MSI_FLAGS_REQUIRED,
613 	.supported_flags	= MTK_MSI_FLAGS_SUPPORTED,
614 	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
615 	.chip_flags		= MSI_CHIP_FLAG_SET_ACK,
616 	.prefix			= "MTK3-",
617 	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
618 };
619 
mtk_compose_msi_msg(struct irq_data * data,struct msi_msg * msg)620 static void mtk_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
621 {
622 	struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
623 	struct mtk_gen3_pcie *pcie = data->domain->host_data;
624 	unsigned long hwirq;
625 
626 	hwirq =	data->hwirq % PCIE_MSI_IRQS_PER_SET;
627 
628 	msg->address_hi = upper_32_bits(msi_set->msg_addr);
629 	msg->address_lo = lower_32_bits(msi_set->msg_addr);
630 	msg->data = hwirq;
631 	dev_dbg(pcie->dev, "msi#%#lx address_hi %#x address_lo %#x data %d\n",
632 		hwirq, msg->address_hi, msg->address_lo, msg->data);
633 }
634 
mtk_msi_bottom_irq_ack(struct irq_data * data)635 static void mtk_msi_bottom_irq_ack(struct irq_data *data)
636 {
637 	struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
638 	unsigned long hwirq;
639 
640 	hwirq =	data->hwirq % PCIE_MSI_IRQS_PER_SET;
641 
642 	writel_relaxed(BIT(hwirq), msi_set->base + PCIE_MSI_SET_STATUS_OFFSET);
643 }
644 
mtk_msi_bottom_irq_mask(struct irq_data * data)645 static void mtk_msi_bottom_irq_mask(struct irq_data *data)
646 {
647 	struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
648 	struct mtk_gen3_pcie *pcie = data->domain->host_data;
649 	unsigned long hwirq, flags;
650 	u32 val;
651 
652 	hwirq =	data->hwirq % PCIE_MSI_IRQS_PER_SET;
653 
654 	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
655 	val = readl_relaxed(msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
656 	val &= ~BIT(hwirq);
657 	writel_relaxed(val, msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
658 	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
659 }
660 
mtk_msi_bottom_irq_unmask(struct irq_data * data)661 static void mtk_msi_bottom_irq_unmask(struct irq_data *data)
662 {
663 	struct mtk_msi_set *msi_set = irq_data_get_irq_chip_data(data);
664 	struct mtk_gen3_pcie *pcie = data->domain->host_data;
665 	unsigned long hwirq, flags;
666 	u32 val;
667 
668 	hwirq =	data->hwirq % PCIE_MSI_IRQS_PER_SET;
669 
670 	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
671 	val = readl_relaxed(msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
672 	val |= BIT(hwirq);
673 	writel_relaxed(val, msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
674 	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
675 }
676 
677 static struct irq_chip mtk_msi_bottom_irq_chip = {
678 	.irq_ack		= mtk_msi_bottom_irq_ack,
679 	.irq_mask		= mtk_msi_bottom_irq_mask,
680 	.irq_unmask		= mtk_msi_bottom_irq_unmask,
681 	.irq_compose_msi_msg	= mtk_compose_msi_msg,
682 	.name			= "MSI",
683 };
684 
mtk_msi_bottom_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * arg)685 static int mtk_msi_bottom_domain_alloc(struct irq_domain *domain,
686 				       unsigned int virq, unsigned int nr_irqs,
687 				       void *arg)
688 {
689 	struct mtk_gen3_pcie *pcie = domain->host_data;
690 	struct mtk_msi_set *msi_set;
691 	int i, hwirq, set_idx;
692 
693 	mutex_lock(&pcie->lock);
694 
695 	hwirq = bitmap_find_free_region(pcie->msi_irq_in_use, PCIE_MSI_IRQS_NUM,
696 					order_base_2(nr_irqs));
697 
698 	mutex_unlock(&pcie->lock);
699 
700 	if (hwirq < 0)
701 		return -ENOSPC;
702 
703 	set_idx = hwirq / PCIE_MSI_IRQS_PER_SET;
704 	msi_set = &pcie->msi_sets[set_idx];
705 
706 	for (i = 0; i < nr_irqs; i++)
707 		irq_domain_set_info(domain, virq + i, hwirq + i,
708 				    &mtk_msi_bottom_irq_chip, msi_set,
709 				    handle_edge_irq, NULL, NULL);
710 
711 	return 0;
712 }
713 
mtk_msi_bottom_domain_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)714 static void mtk_msi_bottom_domain_free(struct irq_domain *domain,
715 				       unsigned int virq, unsigned int nr_irqs)
716 {
717 	struct mtk_gen3_pcie *pcie = domain->host_data;
718 	struct irq_data *data = irq_domain_get_irq_data(domain, virq);
719 
720 	mutex_lock(&pcie->lock);
721 
722 	bitmap_release_region(pcie->msi_irq_in_use, data->hwirq,
723 			      order_base_2(nr_irqs));
724 
725 	mutex_unlock(&pcie->lock);
726 
727 	irq_domain_free_irqs_common(domain, virq, nr_irqs);
728 }
729 
730 static const struct irq_domain_ops mtk_msi_bottom_domain_ops = {
731 	.alloc = mtk_msi_bottom_domain_alloc,
732 	.free = mtk_msi_bottom_domain_free,
733 };
734 
mtk_intx_mask(struct irq_data * data)735 static void mtk_intx_mask(struct irq_data *data)
736 {
737 	struct mtk_gen3_pcie *pcie = irq_data_get_irq_chip_data(data);
738 	unsigned long flags;
739 	u32 val;
740 
741 	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
742 	val = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
743 	val &= ~BIT(data->hwirq + PCIE_INTX_SHIFT);
744 	writel_relaxed(val, pcie->base + PCIE_INT_ENABLE_REG);
745 	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
746 }
747 
mtk_intx_unmask(struct irq_data * data)748 static void mtk_intx_unmask(struct irq_data *data)
749 {
750 	struct mtk_gen3_pcie *pcie = irq_data_get_irq_chip_data(data);
751 	unsigned long flags;
752 	u32 val;
753 
754 	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
755 	val = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
756 	val |= BIT(data->hwirq + PCIE_INTX_SHIFT);
757 	writel_relaxed(val, pcie->base + PCIE_INT_ENABLE_REG);
758 	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
759 }
760 
761 /**
762  * mtk_intx_eoi() - Clear INTx IRQ status at the end of interrupt
763  * @data: pointer to chip specific data
764  *
765  * As an emulated level IRQ, its interrupt status will remain
766  * until the corresponding de-assert message is received; hence that
767  * the status can only be cleared when the interrupt has been serviced.
768  */
mtk_intx_eoi(struct irq_data * data)769 static void mtk_intx_eoi(struct irq_data *data)
770 {
771 	struct mtk_gen3_pcie *pcie = irq_data_get_irq_chip_data(data);
772 	unsigned long hwirq;
773 
774 	hwirq = data->hwirq + PCIE_INTX_SHIFT;
775 	writel_relaxed(BIT(hwirq), pcie->base + PCIE_INT_STATUS_REG);
776 }
777 
778 static struct irq_chip mtk_intx_irq_chip = {
779 	.irq_mask		= mtk_intx_mask,
780 	.irq_unmask		= mtk_intx_unmask,
781 	.irq_eoi		= mtk_intx_eoi,
782 	.name			= "INTx",
783 };
784 
mtk_pcie_intx_map(struct irq_domain * domain,unsigned int irq,irq_hw_number_t hwirq)785 static int mtk_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
786 			     irq_hw_number_t hwirq)
787 {
788 	irq_set_chip_data(irq, domain->host_data);
789 	irq_set_chip_and_handler_name(irq, &mtk_intx_irq_chip,
790 				      handle_fasteoi_irq, "INTx");
791 	return 0;
792 }
793 
794 static const struct irq_domain_ops intx_domain_ops = {
795 	.map = mtk_pcie_intx_map,
796 };
797 
mtk_pcie_init_irq_domains(struct mtk_gen3_pcie * pcie)798 static int mtk_pcie_init_irq_domains(struct mtk_gen3_pcie *pcie)
799 {
800 	struct device *dev = pcie->dev;
801 	struct device_node *intc_node, *node = dev->of_node;
802 	int ret;
803 
804 	raw_spin_lock_init(&pcie->irq_lock);
805 
806 	/* Setup INTx */
807 	intc_node = of_get_child_by_name(node, "interrupt-controller");
808 	if (!intc_node) {
809 		dev_err(dev, "missing interrupt-controller node\n");
810 		return -ENODEV;
811 	}
812 
813 	pcie->intx_domain = irq_domain_create_linear(of_fwnode_handle(intc_node), PCI_NUM_INTX,
814 						     &intx_domain_ops, pcie);
815 	if (!pcie->intx_domain) {
816 		dev_err(dev, "failed to create INTx IRQ domain\n");
817 		ret = -ENODEV;
818 		goto out_put_node;
819 	}
820 
821 	/* Setup MSI */
822 	mutex_init(&pcie->lock);
823 
824 	struct irq_domain_info info = {
825 		.fwnode		= dev_fwnode(dev),
826 		.ops		= &mtk_msi_bottom_domain_ops,
827 		.host_data	= pcie,
828 		.size		= PCIE_MSI_IRQS_NUM,
829 	};
830 
831 	pcie->msi_bottom_domain = msi_create_parent_irq_domain(&info, &mtk_msi_parent_ops);
832 	if (!pcie->msi_bottom_domain) {
833 		dev_err(dev, "failed to create MSI bottom domain\n");
834 		ret = -ENODEV;
835 		goto err_msi_bottom_domain;
836 	}
837 
838 	of_node_put(intc_node);
839 	return 0;
840 
841 err_msi_bottom_domain:
842 	irq_domain_remove(pcie->intx_domain);
843 out_put_node:
844 	of_node_put(intc_node);
845 	return ret;
846 }
847 
mtk_pcie_irq_teardown(struct mtk_gen3_pcie * pcie)848 static void mtk_pcie_irq_teardown(struct mtk_gen3_pcie *pcie)
849 {
850 	irq_set_chained_handler_and_data(pcie->irq, NULL, NULL);
851 
852 	if (pcie->intx_domain)
853 		irq_domain_remove(pcie->intx_domain);
854 
855 	if (pcie->msi_bottom_domain)
856 		irq_domain_remove(pcie->msi_bottom_domain);
857 
858 	irq_dispose_mapping(pcie->irq);
859 }
860 
mtk_pcie_msi_handler(struct mtk_gen3_pcie * pcie,int set_idx)861 static void mtk_pcie_msi_handler(struct mtk_gen3_pcie *pcie, int set_idx)
862 {
863 	struct mtk_msi_set *msi_set = &pcie->msi_sets[set_idx];
864 	unsigned long msi_enable, msi_status;
865 	irq_hw_number_t bit, hwirq;
866 
867 	msi_enable = readl_relaxed(msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
868 
869 	do {
870 		msi_status = readl_relaxed(msi_set->base +
871 					   PCIE_MSI_SET_STATUS_OFFSET);
872 		msi_status &= msi_enable;
873 		if (!msi_status)
874 			break;
875 
876 		for_each_set_bit(bit, &msi_status, PCIE_MSI_IRQS_PER_SET) {
877 			hwirq = bit + set_idx * PCIE_MSI_IRQS_PER_SET;
878 			generic_handle_domain_irq(pcie->msi_bottom_domain, hwirq);
879 		}
880 	} while (true);
881 }
882 
mtk_pcie_irq_handler(struct irq_desc * desc)883 static void mtk_pcie_irq_handler(struct irq_desc *desc)
884 {
885 	struct mtk_gen3_pcie *pcie = irq_desc_get_handler_data(desc);
886 	struct irq_chip *irqchip = irq_desc_get_chip(desc);
887 	unsigned long status;
888 	irq_hw_number_t irq_bit = PCIE_INTX_SHIFT;
889 
890 	chained_irq_enter(irqchip, desc);
891 
892 	status = readl_relaxed(pcie->base + PCIE_INT_STATUS_REG);
893 	for_each_set_bit_from(irq_bit, &status, PCI_NUM_INTX +
894 			      PCIE_INTX_SHIFT)
895 		generic_handle_domain_irq(pcie->intx_domain,
896 					  irq_bit - PCIE_INTX_SHIFT);
897 
898 	irq_bit = PCIE_MSI_SHIFT;
899 	for_each_set_bit_from(irq_bit, &status, PCIE_MSI_SET_NUM +
900 			      PCIE_MSI_SHIFT) {
901 		mtk_pcie_msi_handler(pcie, irq_bit - PCIE_MSI_SHIFT);
902 
903 		writel_relaxed(BIT(irq_bit), pcie->base + PCIE_INT_STATUS_REG);
904 	}
905 
906 	chained_irq_exit(irqchip, desc);
907 }
908 
mtk_pcie_setup_irq(struct mtk_gen3_pcie * pcie)909 static int mtk_pcie_setup_irq(struct mtk_gen3_pcie *pcie)
910 {
911 	struct device *dev = pcie->dev;
912 	struct platform_device *pdev = to_platform_device(dev);
913 	int err;
914 
915 	pcie->irq = platform_get_irq(pdev, 0);
916 	if (pcie->irq < 0)
917 		return pcie->irq;
918 
919 	err = mtk_pcie_init_irq_domains(pcie);
920 	if (err)
921 		return err;
922 
923 	irq_set_chained_handler_and_data(pcie->irq, mtk_pcie_irq_handler, pcie);
924 
925 	return 0;
926 }
927 
mtk_pcie_parse_port(struct mtk_gen3_pcie * pcie)928 static int mtk_pcie_parse_port(struct mtk_gen3_pcie *pcie)
929 {
930 	int i, ret, num_resets = pcie->soc->phy_resets.num_resets;
931 	struct device *dev = pcie->dev;
932 	struct platform_device *pdev = to_platform_device(dev);
933 	struct resource *regs;
934 	u32 num_lanes;
935 
936 	regs = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcie-mac");
937 	if (!regs)
938 		return -EINVAL;
939 	pcie->base = devm_ioremap_resource(dev, regs);
940 	if (IS_ERR(pcie->base))
941 		return dev_err_probe(dev, PTR_ERR(pcie->base), "failed to map register base\n");
942 
943 	pcie->reg_base = regs->start;
944 
945 	for (i = 0; i < num_resets; i++)
946 		pcie->phy_resets[i].id = pcie->soc->phy_resets.id[i];
947 
948 	ret = devm_reset_control_bulk_get_optional_shared(dev, num_resets,
949 							  pcie->phy_resets);
950 	if (ret)
951 		return dev_err_probe(dev, ret, "failed to get PHY bulk reset\n");
952 
953 	pcie->mac_reset = devm_reset_control_get_optional_exclusive(dev, "mac");
954 	if (IS_ERR(pcie->mac_reset))
955 		return dev_err_probe(dev, PTR_ERR(pcie->mac_reset), "failed to get MAC reset\n");
956 
957 	pcie->phy = devm_phy_optional_get(dev, "pcie-phy");
958 	if (IS_ERR(pcie->phy))
959 		return dev_err_probe(dev, PTR_ERR(pcie->phy), "failed to get PHY\n");
960 
961 	pcie->num_clks = devm_clk_bulk_get_all(dev, &pcie->clks);
962 	if (pcie->num_clks < 0)
963 		return dev_err_probe(dev, pcie->num_clks, "failed to get clocks\n");
964 
965 	ret = of_property_read_u32(dev->of_node, "num-lanes", &num_lanes);
966 	if (ret == 0) {
967 		if (num_lanes == 0 || num_lanes > 16 ||
968 		    (num_lanes != 1 && num_lanes % 2))
969 			dev_warn(dev, "invalid num-lanes, using controller defaults\n");
970 		else
971 			pcie->num_lanes = num_lanes;
972 	}
973 
974 	return 0;
975 }
976 
mtk_pcie_en7581_power_up(struct mtk_gen3_pcie * pcie)977 static int mtk_pcie_en7581_power_up(struct mtk_gen3_pcie *pcie)
978 {
979 	struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
980 	struct device *dev = pcie->dev;
981 	struct resource_entry *entry;
982 	struct regmap *pbus_regmap;
983 	u32 val, args[2], size;
984 	resource_size_t addr;
985 	int err;
986 
987 	/*
988 	 * The controller may have been left out of reset by the bootloader
989 	 * so make sure that we get a clean start by asserting resets here.
990 	 */
991 	reset_control_bulk_assert(pcie->soc->phy_resets.num_resets,
992 				  pcie->phy_resets);
993 
994 	/* Wait for the time needed to complete the reset lines assert. */
995 	msleep(PCIE_EN7581_RESET_TIME_MS);
996 
997 	/*
998 	 * Configure PBus base address and base address mask to allow the
999 	 * hw to detect if a given address is accessible on PCIe controller.
1000 	 */
1001 	pbus_regmap = syscon_regmap_lookup_by_phandle_args(dev->of_node,
1002 							   "mediatek,pbus-csr",
1003 							   ARRAY_SIZE(args),
1004 							   args);
1005 	if (IS_ERR(pbus_regmap))
1006 		return PTR_ERR(pbus_regmap);
1007 
1008 	entry = resource_list_first_type(&host->windows, IORESOURCE_MEM);
1009 	if (!entry)
1010 		return -ENODEV;
1011 
1012 	addr = entry->res->start - entry->offset;
1013 	regmap_write(pbus_regmap, args[0], lower_32_bits(addr));
1014 	size = lower_32_bits(resource_size(entry->res));
1015 	regmap_write(pbus_regmap, args[1], GENMASK(31, __fls(size)));
1016 
1017 	/*
1018 	 * Unlike the other MediaTek Gen3 controllers, the Airoha EN7581
1019 	 * requires PHY initialization and power-on before PHY reset deassert.
1020 	 */
1021 	err = phy_init(pcie->phy);
1022 	if (err) {
1023 		dev_err(dev, "failed to initialize PHY\n");
1024 		return err;
1025 	}
1026 
1027 	err = phy_power_on(pcie->phy);
1028 	if (err) {
1029 		dev_err(dev, "failed to power on PHY\n");
1030 		goto err_phy_on;
1031 	}
1032 
1033 	err = reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets,
1034 					  pcie->phy_resets);
1035 	if (err) {
1036 		dev_err(dev, "failed to deassert PHYs\n");
1037 		goto err_phy_deassert;
1038 	}
1039 
1040 	/*
1041 	 * Wait for the time needed to complete the bulk de-assert above.
1042 	 * This time is specific for EN7581 SoC.
1043 	 */
1044 	msleep(PCIE_EN7581_RESET_TIME_MS);
1045 
1046 	pm_runtime_enable(dev);
1047 	pm_runtime_get_sync(dev);
1048 
1049 	val = FIELD_PREP(PCIE_VAL_LN0_DOWNSTREAM, 0x47) |
1050 	      FIELD_PREP(PCIE_VAL_LN1_DOWNSTREAM, 0x47) |
1051 	      FIELD_PREP(PCIE_VAL_LN0_UPSTREAM, 0x41) |
1052 	      FIELD_PREP(PCIE_VAL_LN1_UPSTREAM, 0x41);
1053 	writel_relaxed(val, pcie->base + PCIE_EQ_PRESET_01_REG);
1054 
1055 	val = PCIE_K_PHYPARAM_QUERY | PCIE_K_QUERY_TIMEOUT |
1056 	      FIELD_PREP(PCIE_K_PRESET_TO_USE_16G, 0x80) |
1057 	      FIELD_PREP(PCIE_K_PRESET_TO_USE, 0x2) |
1058 	      FIELD_PREP(PCIE_K_FINETUNE_MAX, 0xf);
1059 	writel_relaxed(val, pcie->base + PCIE_PIPE4_PIE8_REG);
1060 
1061 	err = clk_bulk_prepare_enable(pcie->num_clks, pcie->clks);
1062 	if (err) {
1063 		dev_err(dev, "failed to prepare clock\n");
1064 		goto err_clk_prepare_enable;
1065 	}
1066 
1067 	/*
1068 	 * Airoha EN7581 performs PCIe reset via clk callbacks since it has a
1069 	 * hw issue with PCIE_PE_RSTB signal. Add wait for the time needed to
1070 	 * complete the PCIe reset.
1071 	 */
1072 	msleep(PCIE_T_PVPERL_MS);
1073 
1074 	return 0;
1075 
1076 err_clk_prepare_enable:
1077 	pm_runtime_put_sync(dev);
1078 	pm_runtime_disable(dev);
1079 	reset_control_bulk_assert(pcie->soc->phy_resets.num_resets,
1080 				  pcie->phy_resets);
1081 err_phy_deassert:
1082 	phy_power_off(pcie->phy);
1083 err_phy_on:
1084 	phy_exit(pcie->phy);
1085 
1086 	return err;
1087 }
1088 
mtk_pcie_power_up(struct mtk_gen3_pcie * pcie)1089 static int mtk_pcie_power_up(struct mtk_gen3_pcie *pcie)
1090 {
1091 	struct device *dev = pcie->dev;
1092 	int err;
1093 
1094 	/*
1095 	 * The controller may have been left out of reset by the bootloader
1096 	 * so make sure that we get a clean start by asserting resets here.
1097 	 */
1098 	reset_control_bulk_assert(pcie->soc->phy_resets.num_resets,
1099 				  pcie->phy_resets);
1100 	reset_control_assert(pcie->mac_reset);
1101 	usleep_range(PCIE_MTK_RESET_TIME_US, 2 * PCIE_MTK_RESET_TIME_US);
1102 
1103 	/* PHY power on and enable pipe clock */
1104 	err = reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets,
1105 					  pcie->phy_resets);
1106 	if (err) {
1107 		dev_err(dev, "failed to deassert PHYs\n");
1108 		return err;
1109 	}
1110 
1111 	err = phy_init(pcie->phy);
1112 	if (err) {
1113 		dev_err(dev, "failed to initialize PHY\n");
1114 		goto err_phy_init;
1115 	}
1116 
1117 	err = phy_power_on(pcie->phy);
1118 	if (err) {
1119 		dev_err(dev, "failed to power on PHY\n");
1120 		goto err_phy_on;
1121 	}
1122 
1123 	/* MAC power on and enable transaction layer clocks */
1124 	reset_control_deassert(pcie->mac_reset);
1125 
1126 	pm_runtime_enable(dev);
1127 	pm_runtime_get_sync(dev);
1128 
1129 	err = clk_bulk_prepare_enable(pcie->num_clks, pcie->clks);
1130 	if (err) {
1131 		dev_err(dev, "failed to enable clocks\n");
1132 		goto err_clk_init;
1133 	}
1134 
1135 	return 0;
1136 
1137 err_clk_init:
1138 	pm_runtime_put_sync(dev);
1139 	pm_runtime_disable(dev);
1140 	reset_control_assert(pcie->mac_reset);
1141 	phy_power_off(pcie->phy);
1142 err_phy_on:
1143 	phy_exit(pcie->phy);
1144 err_phy_init:
1145 	reset_control_bulk_assert(pcie->soc->phy_resets.num_resets,
1146 				  pcie->phy_resets);
1147 
1148 	return err;
1149 }
1150 
mtk_pcie_power_down(struct mtk_gen3_pcie * pcie)1151 static void mtk_pcie_power_down(struct mtk_gen3_pcie *pcie)
1152 {
1153 	clk_bulk_disable_unprepare(pcie->num_clks, pcie->clks);
1154 
1155 	pm_runtime_put_sync(pcie->dev);
1156 	pm_runtime_disable(pcie->dev);
1157 	reset_control_assert(pcie->mac_reset);
1158 
1159 	phy_power_off(pcie->phy);
1160 	phy_exit(pcie->phy);
1161 	reset_control_bulk_assert(pcie->soc->phy_resets.num_resets,
1162 				  pcie->phy_resets);
1163 }
1164 
mtk_pcie_get_controller_max_link_speed(struct mtk_gen3_pcie * pcie)1165 static int mtk_pcie_get_controller_max_link_speed(struct mtk_gen3_pcie *pcie)
1166 {
1167 	u32 val;
1168 	int ret;
1169 
1170 	val = readl_relaxed(pcie->base + PCIE_BASE_CFG_REG);
1171 	val = FIELD_GET(PCIE_BASE_CFG_SPEED, val);
1172 	ret = fls(val);
1173 
1174 	return ret > 0 ? ret : -EINVAL;
1175 }
1176 
mtk_pcie_setup(struct mtk_gen3_pcie * pcie)1177 static int mtk_pcie_setup(struct mtk_gen3_pcie *pcie)
1178 {
1179 	int err, max_speed;
1180 
1181 	err = mtk_pcie_parse_port(pcie);
1182 	if (err)
1183 		return err;
1184 
1185 	/*
1186 	 * Deassert the line in order to avoid unbalance in deassert_count
1187 	 * counter since the bulk is shared.
1188 	 */
1189 	reset_control_bulk_deassert(pcie->soc->phy_resets.num_resets,
1190 				    pcie->phy_resets);
1191 
1192 	/* Don't touch the hardware registers before power up */
1193 	err = pcie->soc->power_up(pcie);
1194 	if (err)
1195 		return err;
1196 
1197 	err = of_pci_get_max_link_speed(pcie->dev->of_node);
1198 	if (pcie_get_link_speed(err) != PCI_SPEED_UNKNOWN) {
1199 		/* Get the maximum speed supported by the controller */
1200 		max_speed = mtk_pcie_get_controller_max_link_speed(pcie);
1201 
1202 		/* Set max_link_speed only if the controller supports it */
1203 		if (max_speed >= 0 && max_speed <= err) {
1204 			pcie->max_link_speed = err;
1205 			dev_info(pcie->dev,
1206 				 "maximum controller link speed Gen%d, overriding to Gen%u",
1207 				 max_speed, pcie->max_link_speed);
1208 		}
1209 	}
1210 
1211 	/* Try link up */
1212 	err = mtk_pcie_startup_port(pcie);
1213 	if (err)
1214 		goto err_setup;
1215 
1216 	return 0;
1217 
1218 err_setup:
1219 	mtk_pcie_power_down(pcie);
1220 
1221 	return err;
1222 }
1223 
mtk_pcie_probe(struct platform_device * pdev)1224 static int mtk_pcie_probe(struct platform_device *pdev)
1225 {
1226 	struct device *dev = &pdev->dev;
1227 	struct mtk_gen3_pcie *pcie;
1228 	struct pci_host_bridge *host;
1229 	int err;
1230 
1231 	host = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
1232 	if (!host)
1233 		return -ENOMEM;
1234 
1235 	pcie = pci_host_bridge_priv(host);
1236 
1237 	pcie->dev = dev;
1238 	pcie->soc = device_get_match_data(dev);
1239 	platform_set_drvdata(pdev, pcie);
1240 
1241 	err = mtk_pcie_setup_irq(pcie);
1242 	if (err)
1243 		return dev_err_probe(dev, err, "Failed to setup IRQ domains\n");
1244 
1245 	err = pci_pwrctrl_create_devices(pcie->dev);
1246 	if (err) {
1247 		dev_err_probe(dev, err, "failed to create pwrctrl devices\n");
1248 		goto err_tear_down_irq;
1249 	}
1250 
1251 	err = mtk_pcie_setup(pcie);
1252 	if (err)
1253 		goto err_destroy_pwrctrl;
1254 
1255 	host->ops = &mtk_pcie_ops;
1256 	host->sysdata = pcie;
1257 
1258 	err = pci_host_probe(host);
1259 	if (err)
1260 		goto err_power_down_pcie;
1261 
1262 	return 0;
1263 
1264 err_power_down_pcie:
1265 	mtk_pcie_devices_power_down(pcie);
1266 	mtk_pcie_power_down(pcie);
1267 err_destroy_pwrctrl:
1268 	if (err != -EPROBE_DEFER)
1269 		pci_pwrctrl_destroy_devices(pcie->dev);
1270 err_tear_down_irq:
1271 	mtk_pcie_irq_teardown(pcie);
1272 	return err;
1273 }
1274 
mtk_pcie_remove(struct platform_device * pdev)1275 static void mtk_pcie_remove(struct platform_device *pdev)
1276 {
1277 	struct mtk_gen3_pcie *pcie = platform_get_drvdata(pdev);
1278 	struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
1279 
1280 	pci_lock_rescan_remove();
1281 	pci_stop_root_bus(host->bus);
1282 	pci_remove_root_bus(host->bus);
1283 	pci_unlock_rescan_remove();
1284 
1285 	mtk_pcie_devices_power_down(pcie);
1286 	mtk_pcie_power_down(pcie);
1287 	pci_pwrctrl_destroy_devices(pcie->dev);
1288 	mtk_pcie_irq_teardown(pcie);
1289 }
1290 
mtk_pcie_shutdown(struct platform_device * pdev)1291 static void mtk_pcie_shutdown(struct platform_device *pdev)
1292 {
1293 	struct mtk_gen3_pcie *pcie = platform_get_drvdata(pdev);
1294 
1295 	mtk_pcie_devices_power_down(pcie);
1296 	mtk_pcie_power_down(pcie);
1297 }
1298 
mtk_pcie_irq_save(struct mtk_gen3_pcie * pcie)1299 static void mtk_pcie_irq_save(struct mtk_gen3_pcie *pcie)
1300 {
1301 	int i;
1302 
1303 	raw_spin_lock(&pcie->irq_lock);
1304 
1305 	pcie->saved_irq_state = readl_relaxed(pcie->base + PCIE_INT_ENABLE_REG);
1306 
1307 	for (i = 0; i < PCIE_MSI_SET_NUM; i++) {
1308 		struct mtk_msi_set *msi_set = &pcie->msi_sets[i];
1309 
1310 		msi_set->saved_irq_state = readl_relaxed(msi_set->base +
1311 					   PCIE_MSI_SET_ENABLE_OFFSET);
1312 	}
1313 
1314 	raw_spin_unlock(&pcie->irq_lock);
1315 }
1316 
mtk_pcie_irq_restore(struct mtk_gen3_pcie * pcie)1317 static void mtk_pcie_irq_restore(struct mtk_gen3_pcie *pcie)
1318 {
1319 	int i;
1320 
1321 	raw_spin_lock(&pcie->irq_lock);
1322 
1323 	writel_relaxed(pcie->saved_irq_state, pcie->base + PCIE_INT_ENABLE_REG);
1324 
1325 	for (i = 0; i < PCIE_MSI_SET_NUM; i++) {
1326 		struct mtk_msi_set *msi_set = &pcie->msi_sets[i];
1327 
1328 		writel_relaxed(msi_set->saved_irq_state,
1329 			       msi_set->base + PCIE_MSI_SET_ENABLE_OFFSET);
1330 	}
1331 
1332 	raw_spin_unlock(&pcie->irq_lock);
1333 }
1334 
mtk_pcie_turn_off_link(struct mtk_gen3_pcie * pcie)1335 static int mtk_pcie_turn_off_link(struct mtk_gen3_pcie *pcie)
1336 {
1337 	u32 val;
1338 
1339 	val = readl_relaxed(pcie->base + PCIE_ICMD_PM_REG);
1340 	val |= PCIE_TURN_OFF_LINK;
1341 	writel_relaxed(val, pcie->base + PCIE_ICMD_PM_REG);
1342 
1343 	/* Check the link is L2 */
1344 	return readl_poll_timeout(pcie->base + PCIE_LTSSM_STATUS_REG, val,
1345 				  (PCIE_LTSSM_STATE(val) ==
1346 				   PCIE_LTSSM_STATE_L2_IDLE), 20,
1347 				   50 * USEC_PER_MSEC);
1348 }
1349 
mtk_pcie_suspend_noirq(struct device * dev)1350 static int mtk_pcie_suspend_noirq(struct device *dev)
1351 {
1352 	struct mtk_gen3_pcie *pcie = dev_get_drvdata(dev);
1353 	int err;
1354 
1355 	/* Trigger link to L2 state */
1356 	err = mtk_pcie_turn_off_link(pcie);
1357 	if (err) {
1358 		dev_err(pcie->dev, "cannot enter L2 state\n");
1359 		return err;
1360 	}
1361 
1362 	mtk_pcie_devices_power_down(pcie);
1363 	dev_dbg(pcie->dev, "entered L2 states successfully");
1364 
1365 	mtk_pcie_irq_save(pcie);
1366 	mtk_pcie_power_down(pcie);
1367 
1368 	return 0;
1369 }
1370 
mtk_pcie_resume_noirq(struct device * dev)1371 static int mtk_pcie_resume_noirq(struct device *dev)
1372 {
1373 	struct mtk_gen3_pcie *pcie = dev_get_drvdata(dev);
1374 	int err;
1375 
1376 	err = pcie->soc->power_up(pcie);
1377 	if (err)
1378 		return err;
1379 
1380 	err = mtk_pcie_startup_port(pcie);
1381 	if (err)
1382 		goto err_power_down;
1383 
1384 	mtk_pcie_irq_restore(pcie);
1385 
1386 	return 0;
1387 
1388 err_power_down:
1389 	mtk_pcie_power_down(pcie);
1390 	return err;
1391 }
1392 
1393 static const struct dev_pm_ops mtk_pcie_pm_ops = {
1394 	NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_pcie_suspend_noirq,
1395 				  mtk_pcie_resume_noirq)
1396 };
1397 
1398 static const struct mtk_gen3_pcie_pdata mtk_pcie_soc_mt8192 = {
1399 	.power_up = mtk_pcie_power_up,
1400 	.phy_resets = {
1401 		.id[0] = "phy",
1402 		.num_resets = 1,
1403 	},
1404 };
1405 
1406 static const struct mtk_gen3_pcie_pdata mtk_pcie_soc_mt8196 = {
1407 	.power_up = mtk_pcie_power_up,
1408 	.phy_resets = {
1409 		.id[0] = "phy",
1410 		.num_resets = 1,
1411 	},
1412 	.sys_clk_rdy_time_us = 10,
1413 };
1414 
1415 static const struct mtk_gen3_pcie_pdata mtk_pcie_soc_en7581 = {
1416 	.power_up = mtk_pcie_en7581_power_up,
1417 	.phy_resets = {
1418 		.id[0] = "phy-lane0",
1419 		.id[1] = "phy-lane1",
1420 		.id[2] = "phy-lane2",
1421 		.num_resets = 3,
1422 	},
1423 	.flags = SKIP_PCIE_RSTB,
1424 };
1425 
1426 static const struct of_device_id mtk_pcie_of_match[] = {
1427 	{ .compatible = "airoha,en7581-pcie", .data = &mtk_pcie_soc_en7581 },
1428 	{ .compatible = "mediatek,mt8192-pcie", .data = &mtk_pcie_soc_mt8192 },
1429 	{ .compatible = "mediatek,mt8196-pcie", .data = &mtk_pcie_soc_mt8196 },
1430 	{},
1431 };
1432 MODULE_DEVICE_TABLE(of, mtk_pcie_of_match);
1433 
1434 static struct platform_driver mtk_pcie_driver = {
1435 	.probe = mtk_pcie_probe,
1436 	.remove = mtk_pcie_remove,
1437 	.shutdown = mtk_pcie_shutdown,
1438 	.driver = {
1439 		.name = "mtk-pcie-gen3",
1440 		.of_match_table = mtk_pcie_of_match,
1441 		.pm = &mtk_pcie_pm_ops,
1442 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1443 	},
1444 };
1445 
1446 module_platform_driver(mtk_pcie_driver);
1447 MODULE_DESCRIPTION("MediaTek Gen3 PCIe host controller driver");
1448 MODULE_LICENSE("GPL v2");
1449