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