1 /* 2 * Ralink MT7620A SoC PCI support 3 * 4 * Copyright (C) 2007-2013 Bruce Chang (Mediatek) 5 * Copyright (C) 2013-2016 John Crispin <john@phrozen.org> 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License version 2 as published 9 * by the Free Software Foundation. 10 */ 11 12 #include <linux/types.h> 13 #include <linux/pci.h> 14 #include <linux/io.h> 15 #include <linux/init.h> 16 #include <linux/delay.h> 17 #include <linux/interrupt.h> 18 #include <linux/of.h> 19 #include <linux/of_irq.h> 20 #include <linux/of_pci.h> 21 #include <linux/reset.h> 22 #include <linux/platform_device.h> 23 24 #include <asm/mach-ralink/ralink_regs.h> 25 #include <asm/mach-ralink/mt7620.h> 26 27 #define RALINK_PCI_IO_MAP_BASE 0x10160000 28 #define RALINK_PCI_MEMORY_BASE 0x0 29 30 #define RALINK_INT_PCIE0 4 31 32 #define RALINK_CLKCFG1 0x30 33 #define RALINK_GPIOMODE 0x60 34 35 #define PPLL_CFG1 0x9c 36 #define PDRV_SW_SET BIT(23) 37 38 #define PPLL_DRV 0xa0 39 #define PDRV_SW_SET (1<<31) 40 #define LC_CKDRVPD (1<<19) 41 #define LC_CKDRVOHZ (1<<18) 42 #define LC_CKDRVHZ (1<<17) 43 #define LC_CKTEST (1<<16) 44 45 /* PCI Bridge registers */ 46 #define RALINK_PCI_PCICFG_ADDR 0x00 47 #define PCIRST BIT(1) 48 49 #define RALINK_PCI_PCIENA 0x0C 50 #define PCIINT2 BIT(20) 51 52 #define RALINK_PCI_CONFIG_ADDR 0x20 53 #define RALINK_PCI_CONFIG_DATA_VIRT_REG 0x24 54 #define RALINK_PCI_MEMBASE 0x28 55 #define RALINK_PCI_IOBASE 0x2C 56 57 /* PCI RC registers */ 58 #define RALINK_PCI0_BAR0SETUP_ADDR 0x10 59 #define RALINK_PCI0_IMBASEBAR0_ADDR 0x18 60 #define RALINK_PCI0_ID 0x30 61 #define RALINK_PCI0_CLASS 0x34 62 #define RALINK_PCI0_SUBID 0x38 63 #define RALINK_PCI0_STATUS 0x50 64 #define PCIE_LINK_UP_ST BIT(0) 65 66 #define PCIEPHY0_CFG 0x90 67 68 #define RALINK_PCIEPHY_P0_CTL_OFFSET 0x7498 69 #define RALINK_PCIE0_CLK_EN (1 << 26) 70 71 #define BUSY 0x80000000 72 #define WAITRETRY_MAX 10 73 #define WRITE_MODE (1UL << 23) 74 #define DATA_SHIFT 0 75 #define ADDR_SHIFT 8 76 77 78 static void __iomem *bridge_base; 79 static void __iomem *pcie_base; 80 81 static struct reset_control *rstpcie0; 82 83 static inline void bridge_w32(u32 val, unsigned reg) 84 { 85 iowrite32(val, bridge_base + reg); 86 } 87 88 static inline u32 bridge_r32(unsigned reg) 89 { 90 return ioread32(bridge_base + reg); 91 } 92 93 static inline void pcie_w32(u32 val, unsigned reg) 94 { 95 iowrite32(val, pcie_base + reg); 96 } 97 98 static inline u32 pcie_r32(unsigned reg) 99 { 100 return ioread32(pcie_base + reg); 101 } 102 103 static inline void pcie_m32(u32 clr, u32 set, unsigned reg) 104 { 105 u32 val = pcie_r32(reg); 106 107 val &= ~clr; 108 val |= set; 109 pcie_w32(val, reg); 110 } 111 112 static int wait_pciephy_busy(void) 113 { 114 unsigned long reg_value = 0x0, retry = 0; 115 116 while (1) { 117 reg_value = pcie_r32(PCIEPHY0_CFG); 118 119 if (reg_value & BUSY) 120 mdelay(100); 121 else 122 break; 123 if (retry++ > WAITRETRY_MAX) { 124 printk(KERN_WARN "PCIE-PHY retry failed.\n"); 125 return -1; 126 } 127 } 128 return 0; 129 } 130 131 static void pcie_phy(unsigned long addr, unsigned long val) 132 { 133 wait_pciephy_busy(); 134 pcie_w32(WRITE_MODE | (val << DATA_SHIFT) | (addr << ADDR_SHIFT), 135 PCIEPHY0_CFG); 136 mdelay(1); 137 wait_pciephy_busy(); 138 } 139 140 static int pci_config_read(struct pci_bus *bus, unsigned int devfn, int where, 141 int size, u32 *val) 142 { 143 unsigned int slot = PCI_SLOT(devfn); 144 u8 func = PCI_FUNC(devfn); 145 u32 address; 146 u32 data; 147 u32 num = 0; 148 149 if (bus) 150 num = bus->number; 151 152 address = (((where & 0xF00) >> 8) << 24) | (num << 16) | (slot << 11) | 153 (func << 8) | (where & 0xfc) | 0x80000000; 154 bridge_w32(address, RALINK_PCI_CONFIG_ADDR); 155 data = bridge_r32(RALINK_PCI_CONFIG_DATA_VIRT_REG); 156 157 switch (size) { 158 case 1: 159 *val = (data >> ((where & 3) << 3)) & 0xff; 160 break; 161 case 2: 162 *val = (data >> ((where & 3) << 3)) & 0xffff; 163 break; 164 case 4: 165 *val = data; 166 break; 167 } 168 169 return PCIBIOS_SUCCESSFUL; 170 } 171 172 static int pci_config_write(struct pci_bus *bus, unsigned int devfn, int where, 173 int size, u32 val) 174 { 175 unsigned int slot = PCI_SLOT(devfn); 176 u8 func = PCI_FUNC(devfn); 177 u32 address; 178 u32 data; 179 u32 num = 0; 180 181 if (bus) 182 num = bus->number; 183 184 address = (((where & 0xF00) >> 8) << 24) | (num << 16) | (slot << 11) | 185 (func << 8) | (where & 0xfc) | 0x80000000; 186 bridge_w32(address, RALINK_PCI_CONFIG_ADDR); 187 data = bridge_r32(RALINK_PCI_CONFIG_DATA_VIRT_REG); 188 189 switch (size) { 190 case 1: 191 data = (data & ~(0xff << ((where & 3) << 3))) | 192 (val << ((where & 3) << 3)); 193 break; 194 case 2: 195 data = (data & ~(0xffff << ((where & 3) << 3))) | 196 (val << ((where & 3) << 3)); 197 break; 198 case 4: 199 data = val; 200 break; 201 } 202 203 bridge_w32(data, RALINK_PCI_CONFIG_DATA_VIRT_REG); 204 205 return PCIBIOS_SUCCESSFUL; 206 } 207 208 struct pci_ops mt7620_pci_ops = { 209 .read = pci_config_read, 210 .write = pci_config_write, 211 }; 212 213 static struct resource mt7620_res_pci_mem1; 214 static struct resource mt7620_res_pci_io1; 215 struct pci_controller mt7620_controller = { 216 .pci_ops = &mt7620_pci_ops, 217 .mem_resource = &mt7620_res_pci_mem1, 218 .mem_offset = 0x00000000UL, 219 .io_resource = &mt7620_res_pci_io1, 220 .io_offset = 0x00000000UL, 221 .io_map_base = 0xa0000000, 222 }; 223 224 static int mt7620_pci_hw_init(struct platform_device *pdev) 225 { 226 /* bypass PCIe DLL */ 227 pcie_phy(0x0, 0x80); 228 pcie_phy(0x1, 0x04); 229 230 /* Elastic buffer control */ 231 pcie_phy(0x68, 0xB4); 232 233 /* put core into reset */ 234 pcie_m32(0, PCIRST, RALINK_PCI_PCICFG_ADDR); 235 reset_control_assert(rstpcie0); 236 237 /* disable power and all clocks */ 238 rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1); 239 rt_sysc_m32(LC_CKDRVPD, PDRV_SW_SET, PPLL_DRV); 240 241 /* bring core out of reset */ 242 reset_control_deassert(rstpcie0); 243 rt_sysc_m32(0, RALINK_PCIE0_CLK_EN, RALINK_CLKCFG1); 244 mdelay(100); 245 246 if (!(rt_sysc_r32(PPLL_CFG1) & PDRV_SW_SET)) { 247 dev_err(&pdev->dev, "MT7620 PPLL unlock\n"); 248 reset_control_assert(rstpcie0); 249 rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1); 250 return -1; 251 } 252 253 /* power up the bus */ 254 rt_sysc_m32(LC_CKDRVHZ | LC_CKDRVOHZ, LC_CKDRVPD | PDRV_SW_SET, 255 PPLL_DRV); 256 257 return 0; 258 } 259 260 static int mt7628_pci_hw_init(struct platform_device *pdev) 261 { 262 u32 val = 0; 263 264 /* bring the core out of reset */ 265 rt_sysc_m32(BIT(16), 0, RALINK_GPIOMODE); 266 reset_control_deassert(rstpcie0); 267 268 /* enable the pci clk */ 269 rt_sysc_m32(0, RALINK_PCIE0_CLK_EN, RALINK_CLKCFG1); 270 mdelay(100); 271 272 /* voodoo from the SDK driver */ 273 pcie_m32(~0xff, 0x5, RALINK_PCIEPHY_P0_CTL_OFFSET); 274 275 pci_config_read(NULL, 0, 0x70c, 4, &val); 276 val &= ~(0xff) << 8; 277 val |= 0x50 << 8; 278 pci_config_write(NULL, 0, 0x70c, 4, val); 279 280 pci_config_read(NULL, 0, 0x70c, 4, &val); 281 dev_err(&pdev->dev, "Port 0 N_FTS = %x\n", (unsigned int) val); 282 283 return 0; 284 } 285 286 static int mt7620_pci_probe(struct platform_device *pdev) 287 { 288 struct resource *bridge_res = platform_get_resource(pdev, 289 IORESOURCE_MEM, 0); 290 struct resource *pcie_res = platform_get_resource(pdev, 291 IORESOURCE_MEM, 1); 292 u32 val = 0; 293 294 rstpcie0 = devm_reset_control_get(&pdev->dev, "pcie0"); 295 if (IS_ERR(rstpcie0)) 296 return PTR_ERR(rstpcie0); 297 298 bridge_base = devm_ioremap_resource(&pdev->dev, bridge_res); 299 if (IS_ERR(bridge_base)) 300 return PTR_ERR(bridge_base); 301 302 pcie_base = devm_ioremap_resource(&pdev->dev, pcie_res); 303 if (IS_ERR(pcie_base)) 304 return PTR_ERR(pcie_base); 305 306 iomem_resource.start = 0; 307 iomem_resource.end = ~0; 308 ioport_resource.start = 0; 309 ioport_resource.end = ~0; 310 311 /* bring up the pci core */ 312 switch (ralink_soc) { 313 case MT762X_SOC_MT7620A: 314 if (mt7620_pci_hw_init(pdev)) 315 return -1; 316 break; 317 318 case MT762X_SOC_MT7628AN: 319 if (mt7628_pci_hw_init(pdev)) 320 return -1; 321 break; 322 323 default: 324 dev_err(&pdev->dev, "pcie is not supported on this hardware\n"); 325 return -1; 326 } 327 mdelay(50); 328 329 /* enable write access */ 330 pcie_m32(PCIRST, 0, RALINK_PCI_PCICFG_ADDR); 331 mdelay(100); 332 333 /* check if there is a card present */ 334 if ((pcie_r32(RALINK_PCI0_STATUS) & PCIE_LINK_UP_ST) == 0) { 335 reset_control_assert(rstpcie0); 336 rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1); 337 if (ralink_soc == MT762X_SOC_MT7620A) 338 rt_sysc_m32(LC_CKDRVPD, PDRV_SW_SET, PPLL_DRV); 339 dev_err(&pdev->dev, "PCIE0 no card, disable it(RST&CLK)\n"); 340 return -1; 341 } 342 343 /* setup ranges */ 344 bridge_w32(0xffffffff, RALINK_PCI_MEMBASE); 345 bridge_w32(RALINK_PCI_IO_MAP_BASE, RALINK_PCI_IOBASE); 346 347 pcie_w32(0x7FFF0001, RALINK_PCI0_BAR0SETUP_ADDR); 348 pcie_w32(RALINK_PCI_MEMORY_BASE, RALINK_PCI0_IMBASEBAR0_ADDR); 349 pcie_w32(0x06040001, RALINK_PCI0_CLASS); 350 351 /* enable interrupts */ 352 pcie_m32(0, PCIINT2, RALINK_PCI_PCIENA); 353 354 /* voodoo from the SDK driver */ 355 pci_config_read(NULL, 0, 4, 4, &val); 356 pci_config_write(NULL, 0, 4, 4, val | 0x7); 357 358 pci_load_of_ranges(&mt7620_controller, pdev->dev.of_node); 359 register_pci_controller(&mt7620_controller); 360 361 return 0; 362 } 363 364 int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin) 365 { 366 u16 cmd; 367 u32 val; 368 int irq = 0; 369 370 if ((dev->bus->number == 0) && (slot == 0)) { 371 pcie_w32(0x7FFF0001, RALINK_PCI0_BAR0SETUP_ADDR); 372 pci_config_write(dev->bus, 0, PCI_BASE_ADDRESS_0, 4, 373 RALINK_PCI_MEMORY_BASE); 374 pci_config_read(dev->bus, 0, PCI_BASE_ADDRESS_0, 4, &val); 375 } else if ((dev->bus->number == 1) && (slot == 0x0)) { 376 irq = RALINK_INT_PCIE0; 377 } else { 378 dev_err(&dev->dev, "no irq found - bus=0x%x, slot = 0x%x\n", 379 dev->bus->number, slot); 380 return 0; 381 } 382 dev_err(&dev->dev, "card - bus=0x%x, slot = 0x%x irq=%d\n", 383 dev->bus->number, slot, irq); 384 385 /* configure the cache line size to 0x14 */ 386 pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, 0x14); 387 388 /* configure latency timer to 0xff */ 389 pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0xff); 390 pci_read_config_word(dev, PCI_COMMAND, &cmd); 391 392 /* setup the slot */ 393 cmd = cmd | PCI_COMMAND_MASTER | PCI_COMMAND_IO | PCI_COMMAND_MEMORY; 394 pci_write_config_word(dev, PCI_COMMAND, cmd); 395 pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq); 396 397 return irq; 398 } 399 400 int pcibios_plat_dev_init(struct pci_dev *dev) 401 { 402 return 0; 403 } 404 405 static const struct of_device_id mt7620_pci_ids[] = { 406 { .compatible = "mediatek,mt7620-pci" }, 407 {}, 408 }; 409 410 static struct platform_driver mt7620_pci_driver = { 411 .probe = mt7620_pci_probe, 412 .driver = { 413 .name = "mt7620-pci", 414 .of_match_table = of_match_ptr(mt7620_pci_ids), 415 }, 416 }; 417 418 static int __init mt7620_pci_init(void) 419 { 420 return platform_driver_register(&mt7620_pci_driver); 421 } 422 423 arch_initcall(mt7620_pci_init); 424