1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Ralink MT7620A SoC PCI support 4 * 5 * Copyright (C) 2007-2013 Bruce Chang (Mediatek) 6 * Copyright (C) 2013-2016 John Crispin <john@phrozen.org> 7 */ 8 9 #include <linux/types.h> 10 #include <linux/pci.h> 11 #include <linux/io.h> 12 #include <linux/init.h> 13 #include <linux/delay.h> 14 #include <linux/interrupt.h> 15 #include <linux/of.h> 16 #include <linux/of_irq.h> 17 #include <linux/of_pci.h> 18 #include <linux/reset.h> 19 #include <linux/platform_device.h> 20 21 #include <asm/mach-ralink/ralink_regs.h> 22 #include <asm/mach-ralink/mt7620.h> 23 24 #define RALINK_PCI_IO_MAP_BASE 0x10160000 25 #define RALINK_PCI_MEMORY_BASE 0x0 26 27 #define RALINK_INT_PCIE0 4 28 29 #define RALINK_CLKCFG1 0x30 30 #define RALINK_GPIOMODE 0x60 31 32 #define PPLL_CFG1 0x9c 33 #define PPLL_LD BIT(23) 34 35 #define PPLL_DRV 0xa0 36 #define PDRV_SW_SET BIT(31) 37 #define LC_CKDRVPD BIT(19) 38 #define LC_CKDRVOHZ BIT(18) 39 #define LC_CKDRVHZ BIT(17) 40 #define LC_CKTEST BIT(16) 41 42 /* PCI Bridge registers */ 43 #define RALINK_PCI_PCICFG_ADDR 0x00 44 #define PCIRST BIT(1) 45 46 #define RALINK_PCI_PCIENA 0x0C 47 #define PCIINT2 BIT(20) 48 49 #define RALINK_PCI_CONFIG_ADDR 0x20 50 #define RALINK_PCI_CONFIG_DATA_VIRT_REG 0x24 51 #define RALINK_PCI_MEMBASE 0x28 52 #define RALINK_PCI_IOBASE 0x2C 53 54 /* PCI RC registers */ 55 #define RALINK_PCI0_BAR0SETUP_ADDR 0x10 56 #define RALINK_PCI0_IMBASEBAR0_ADDR 0x18 57 #define RALINK_PCI0_ID 0x30 58 #define RALINK_PCI0_CLASS 0x34 59 #define RALINK_PCI0_SUBID 0x38 60 #define RALINK_PCI0_STATUS 0x50 61 #define PCIE_LINK_UP_ST BIT(0) 62 63 #define PCIEPHY0_CFG 0x90 64 65 #define RALINK_PCIEPHY_P0_CTL_OFFSET 0x7498 66 #define RALINK_PCIE0_CLK_EN BIT(26) 67 68 #define BUSY 0x80000000 69 #define WAITRETRY_MAX 10 70 #define WRITE_MODE (1UL << 23) 71 #define DATA_SHIFT 0 72 #define ADDR_SHIFT 8 73 74 75 static void __iomem *bridge_base; 76 static void __iomem *pcie_base; 77 78 static struct reset_control *rstpcie0; 79 80 static inline void bridge_w32(u32 val, unsigned reg) 81 { 82 iowrite32(val, bridge_base + reg); 83 } 84 85 static inline u32 bridge_r32(unsigned reg) 86 { 87 return ioread32(bridge_base + reg); 88 } 89 90 static inline void pcie_w32(u32 val, unsigned reg) 91 { 92 iowrite32(val, pcie_base + reg); 93 } 94 95 static inline u32 pcie_r32(unsigned reg) 96 { 97 return ioread32(pcie_base + reg); 98 } 99 100 static inline void pcie_m32(u32 clr, u32 set, unsigned reg) 101 { 102 u32 val = pcie_r32(reg); 103 104 val &= ~clr; 105 val |= set; 106 pcie_w32(val, reg); 107 } 108 109 static int wait_pciephy_busy(void) 110 { 111 unsigned long reg_value = 0x0, retry = 0; 112 113 while (1) { 114 reg_value = pcie_r32(PCIEPHY0_CFG); 115 116 if (reg_value & BUSY) 117 mdelay(100); 118 else 119 break; 120 if (retry++ > WAITRETRY_MAX) { 121 pr_warn("PCIE-PHY retry failed.\n"); 122 return -1; 123 } 124 } 125 return 0; 126 } 127 128 static void pcie_phy(unsigned long addr, unsigned long val) 129 { 130 wait_pciephy_busy(); 131 pcie_w32(WRITE_MODE | (val << DATA_SHIFT) | (addr << ADDR_SHIFT), 132 PCIEPHY0_CFG); 133 mdelay(1); 134 wait_pciephy_busy(); 135 } 136 137 static int pci_config_read(struct pci_bus *bus, unsigned int devfn, int where, 138 int size, u32 *val) 139 { 140 unsigned int slot = PCI_SLOT(devfn); 141 u8 func = PCI_FUNC(devfn); 142 u32 address; 143 u32 data; 144 u32 num = 0; 145 146 if (bus) 147 num = bus->number; 148 149 address = (((where & 0xF00) >> 8) << 24) | (num << 16) | (slot << 11) | 150 (func << 8) | (where & 0xfc) | 0x80000000; 151 bridge_w32(address, RALINK_PCI_CONFIG_ADDR); 152 data = bridge_r32(RALINK_PCI_CONFIG_DATA_VIRT_REG); 153 154 switch (size) { 155 case 1: 156 *val = (data >> ((where & 3) << 3)) & 0xff; 157 break; 158 case 2: 159 *val = (data >> ((where & 3) << 3)) & 0xffff; 160 break; 161 case 4: 162 *val = data; 163 break; 164 } 165 166 return PCIBIOS_SUCCESSFUL; 167 } 168 169 static int pci_config_write(struct pci_bus *bus, unsigned int devfn, int where, 170 int size, u32 val) 171 { 172 unsigned int slot = PCI_SLOT(devfn); 173 u8 func = PCI_FUNC(devfn); 174 u32 address; 175 u32 data; 176 u32 num = 0; 177 178 if (bus) 179 num = bus->number; 180 181 address = (((where & 0xF00) >> 8) << 24) | (num << 16) | (slot << 11) | 182 (func << 8) | (where & 0xfc) | 0x80000000; 183 bridge_w32(address, RALINK_PCI_CONFIG_ADDR); 184 data = bridge_r32(RALINK_PCI_CONFIG_DATA_VIRT_REG); 185 186 switch (size) { 187 case 1: 188 data = (data & ~(0xff << ((where & 3) << 3))) | 189 (val << ((where & 3) << 3)); 190 break; 191 case 2: 192 data = (data & ~(0xffff << ((where & 3) << 3))) | 193 (val << ((where & 3) << 3)); 194 break; 195 case 4: 196 data = val; 197 break; 198 } 199 200 bridge_w32(data, RALINK_PCI_CONFIG_DATA_VIRT_REG); 201 202 return PCIBIOS_SUCCESSFUL; 203 } 204 205 struct pci_ops mt7620_pci_ops = { 206 .read = pci_config_read, 207 .write = pci_config_write, 208 }; 209 210 static struct resource mt7620_res_pci_mem1; 211 static struct resource mt7620_res_pci_io1; 212 struct pci_controller mt7620_controller = { 213 .pci_ops = &mt7620_pci_ops, 214 .mem_resource = &mt7620_res_pci_mem1, 215 .mem_offset = 0x00000000UL, 216 .io_resource = &mt7620_res_pci_io1, 217 .io_offset = 0x00000000UL, 218 .io_map_base = 0xa0000000, 219 }; 220 221 static int mt7620_pci_hw_init(struct platform_device *pdev) 222 { 223 /* bypass PCIe DLL */ 224 pcie_phy(0x0, 0x80); 225 pcie_phy(0x1, 0x04); 226 227 /* Elastic buffer control */ 228 pcie_phy(0x68, 0xB4); 229 230 /* put core into reset */ 231 pcie_m32(0, PCIRST, RALINK_PCI_PCICFG_ADDR); 232 reset_control_assert(rstpcie0); 233 234 /* disable power and all clocks */ 235 rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1); 236 rt_sysc_m32(LC_CKDRVPD, PDRV_SW_SET, PPLL_DRV); 237 238 /* bring core out of reset */ 239 reset_control_deassert(rstpcie0); 240 rt_sysc_m32(0, RALINK_PCIE0_CLK_EN, RALINK_CLKCFG1); 241 mdelay(100); 242 243 if (!(rt_sysc_r32(PPLL_CFG1) & PPLL_LD)) { 244 dev_err(&pdev->dev, "pcie PLL not locked, aborting init\n"); 245 reset_control_assert(rstpcie0); 246 rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1); 247 return -1; 248 } 249 250 /* power up the bus */ 251 rt_sysc_m32(LC_CKDRVHZ | LC_CKDRVOHZ, LC_CKDRVPD | PDRV_SW_SET, 252 PPLL_DRV); 253 254 return 0; 255 } 256 257 static int mt7628_pci_hw_init(struct platform_device *pdev) 258 { 259 u32 val = 0; 260 261 /* bring the core out of reset */ 262 rt_sysc_m32(BIT(16), 0, RALINK_GPIOMODE); 263 reset_control_deassert(rstpcie0); 264 265 /* enable the pci clk */ 266 rt_sysc_m32(0, RALINK_PCIE0_CLK_EN, RALINK_CLKCFG1); 267 mdelay(100); 268 269 /* voodoo from the SDK driver */ 270 pcie_m32(~0xff, 0x5, RALINK_PCIEPHY_P0_CTL_OFFSET); 271 272 pci_config_read(NULL, 0, 0x70c, 4, &val); 273 val &= ~(0xff) << 8; 274 val |= 0x50 << 8; 275 pci_config_write(NULL, 0, 0x70c, 4, val); 276 277 pci_config_read(NULL, 0, 0x70c, 4, &val); 278 dev_err(&pdev->dev, "Port 0 N_FTS = %x\n", (unsigned int) val); 279 280 return 0; 281 } 282 283 static int mt7620_pci_probe(struct platform_device *pdev) 284 { 285 u32 val = 0; 286 287 rstpcie0 = devm_reset_control_get_exclusive(&pdev->dev, "pcie0"); 288 if (IS_ERR(rstpcie0)) 289 return PTR_ERR(rstpcie0); 290 291 bridge_base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); 292 if (IS_ERR(bridge_base)) 293 return PTR_ERR(bridge_base); 294 295 pcie_base = devm_platform_get_and_ioremap_resource(pdev, 1, NULL); 296 if (IS_ERR(pcie_base)) 297 return PTR_ERR(pcie_base); 298 299 iomem_resource.start = 0; 300 iomem_resource.end = ~0; 301 ioport_resource.start = 0; 302 ioport_resource.end = ~0; 303 304 /* bring up the pci core */ 305 switch (ralink_soc) { 306 case MT762X_SOC_MT7620A: 307 if (mt7620_pci_hw_init(pdev)) 308 return -1; 309 break; 310 311 case MT762X_SOC_MT7628AN: 312 case MT762X_SOC_MT7688: 313 if (mt7628_pci_hw_init(pdev)) 314 return -1; 315 break; 316 317 default: 318 dev_err(&pdev->dev, "pcie is not supported on this hardware\n"); 319 return -1; 320 } 321 mdelay(50); 322 323 /* enable write access */ 324 pcie_m32(PCIRST, 0, RALINK_PCI_PCICFG_ADDR); 325 mdelay(100); 326 327 /* check if there is a card present */ 328 if ((pcie_r32(RALINK_PCI0_STATUS) & PCIE_LINK_UP_ST) == 0) { 329 reset_control_assert(rstpcie0); 330 rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1); 331 if (ralink_soc == MT762X_SOC_MT7620A) 332 rt_sysc_m32(LC_CKDRVPD, PDRV_SW_SET, PPLL_DRV); 333 dev_err(&pdev->dev, "PCIE0 no card, disable it(RST&CLK)\n"); 334 return -1; 335 } 336 337 /* setup ranges */ 338 bridge_w32(0xffffffff, RALINK_PCI_MEMBASE); 339 bridge_w32(RALINK_PCI_IO_MAP_BASE, RALINK_PCI_IOBASE); 340 341 pcie_w32(0x7FFF0001, RALINK_PCI0_BAR0SETUP_ADDR); 342 pcie_w32(RALINK_PCI_MEMORY_BASE, RALINK_PCI0_IMBASEBAR0_ADDR); 343 pcie_w32(0x06040001, RALINK_PCI0_CLASS); 344 345 /* enable interrupts */ 346 pcie_m32(0, PCIINT2, RALINK_PCI_PCIENA); 347 348 /* voodoo from the SDK driver */ 349 pci_config_read(NULL, 0, 4, 4, &val); 350 pci_config_write(NULL, 0, 4, 4, val | 0x7); 351 352 pci_load_of_ranges(&mt7620_controller, pdev->dev.of_node); 353 register_pci_controller(&mt7620_controller); 354 355 return 0; 356 } 357 358 int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) 359 { 360 u16 cmd; 361 u32 val; 362 int irq = 0; 363 364 if ((dev->bus->number == 0) && (slot == 0)) { 365 pcie_w32(0x7FFF0001, RALINK_PCI0_BAR0SETUP_ADDR); 366 pci_config_write(dev->bus, 0, PCI_BASE_ADDRESS_0, 4, 367 RALINK_PCI_MEMORY_BASE); 368 pci_config_read(dev->bus, 0, PCI_BASE_ADDRESS_0, 4, &val); 369 } else if ((dev->bus->number == 1) && (slot == 0x0)) { 370 irq = RALINK_INT_PCIE0; 371 } else { 372 dev_err(&dev->dev, "no irq found - bus=0x%x, slot = 0x%x\n", 373 dev->bus->number, slot); 374 return 0; 375 } 376 dev_err(&dev->dev, "card - bus=0x%x, slot = 0x%x irq=%d\n", 377 dev->bus->number, slot, irq); 378 379 /* configure the cache line size to 0x14 */ 380 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, 0x14); 381 382 /* configure latency timer to 0xff */ 383 pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0xff); 384 pci_read_config_word(dev, PCI_COMMAND, &cmd); 385 386 /* setup the slot */ 387 cmd = cmd | PCI_COMMAND_MASTER | PCI_COMMAND_IO | PCI_COMMAND_MEMORY; 388 pci_write_config_word(dev, PCI_COMMAND, cmd); 389 pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq); 390 391 return irq; 392 } 393 394 int pcibios_plat_dev_init(struct pci_dev *dev) 395 { 396 return 0; 397 } 398 399 static const struct of_device_id mt7620_pci_ids[] = { 400 { .compatible = "mediatek,mt7620-pci" }, 401 {}, 402 }; 403 404 static struct platform_driver mt7620_pci_driver = { 405 .probe = mt7620_pci_probe, 406 .driver = { 407 .name = "mt7620-pci", 408 .of_match_table = of_match_ptr(mt7620_pci_ids), 409 }, 410 }; 411 412 static int __init mt7620_pci_init(void) 413 { 414 return platform_driver_register(&mt7620_pci_driver); 415 } 416 417 arch_initcall(mt7620_pci_init); 418