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