1 /* 2 * Atheros AR71xx PCI host controller driver 3 * 4 * Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org> 5 * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org> 6 * 7 * Parts of this file are based on Atheros' 2.6.15 BSP 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License version 2 as published 11 * by the Free Software Foundation. 12 */ 13 14 #include <linux/resource.h> 15 #include <linux/types.h> 16 #include <linux/delay.h> 17 #include <linux/bitops.h> 18 #include <linux/pci.h> 19 #include <linux/pci_regs.h> 20 #include <linux/interrupt.h> 21 #include <linux/module.h> 22 #include <linux/platform_device.h> 23 24 #include <asm/mach-ath79/ar71xx_regs.h> 25 #include <asm/mach-ath79/ath79.h> 26 27 #define AR71XX_PCI_REG_CRP_AD_CBE 0x00 28 #define AR71XX_PCI_REG_CRP_WRDATA 0x04 29 #define AR71XX_PCI_REG_CRP_RDDATA 0x08 30 #define AR71XX_PCI_REG_CFG_AD 0x0c 31 #define AR71XX_PCI_REG_CFG_CBE 0x10 32 #define AR71XX_PCI_REG_CFG_WRDATA 0x14 33 #define AR71XX_PCI_REG_CFG_RDDATA 0x18 34 #define AR71XX_PCI_REG_PCI_ERR 0x1c 35 #define AR71XX_PCI_REG_PCI_ERR_ADDR 0x20 36 #define AR71XX_PCI_REG_AHB_ERR 0x24 37 #define AR71XX_PCI_REG_AHB_ERR_ADDR 0x28 38 39 #define AR71XX_PCI_CRP_CMD_WRITE 0x00010000 40 #define AR71XX_PCI_CRP_CMD_READ 0x00000000 41 #define AR71XX_PCI_CFG_CMD_READ 0x0000000a 42 #define AR71XX_PCI_CFG_CMD_WRITE 0x0000000b 43 44 #define AR71XX_PCI_INT_CORE BIT(4) 45 #define AR71XX_PCI_INT_DEV2 BIT(2) 46 #define AR71XX_PCI_INT_DEV1 BIT(1) 47 #define AR71XX_PCI_INT_DEV0 BIT(0) 48 49 #define AR71XX_PCI_IRQ_COUNT 5 50 51 struct ar71xx_pci_controller { 52 void __iomem *cfg_base; 53 int irq; 54 int irq_base; 55 struct pci_controller pci_ctrl; 56 struct resource io_res; 57 struct resource mem_res; 58 }; 59 60 /* Byte lane enable bits */ 61 static const u8 ar71xx_pci_ble_table[4][4] = { 62 {0x0, 0xf, 0xf, 0xf}, 63 {0xe, 0xd, 0xb, 0x7}, 64 {0xc, 0xf, 0x3, 0xf}, 65 {0xf, 0xf, 0xf, 0xf}, 66 }; 67 68 static const u32 ar71xx_pci_read_mask[8] = { 69 0, 0xff, 0xffff, 0, 0xffffffff, 0, 0, 0 70 }; 71 72 static inline u32 ar71xx_pci_get_ble(int where, int size, int local) 73 { 74 u32 t; 75 76 t = ar71xx_pci_ble_table[size & 3][where & 3]; 77 BUG_ON(t == 0xf); 78 t <<= (local) ? 20 : 4; 79 80 return t; 81 } 82 83 static inline u32 ar71xx_pci_bus_addr(struct pci_bus *bus, unsigned int devfn, 84 int where) 85 { 86 u32 ret; 87 88 if (!bus->number) { 89 /* type 0 */ 90 ret = (1 << PCI_SLOT(devfn)) | (PCI_FUNC(devfn) << 8) | 91 (where & ~3); 92 } else { 93 /* type 1 */ 94 ret = (bus->number << 16) | (PCI_SLOT(devfn) << 11) | 95 (PCI_FUNC(devfn) << 8) | (where & ~3) | 1; 96 } 97 98 return ret; 99 } 100 101 static inline struct ar71xx_pci_controller * 102 pci_bus_to_ar71xx_controller(struct pci_bus *bus) 103 { 104 struct pci_controller *hose; 105 106 hose = (struct pci_controller *) bus->sysdata; 107 return container_of(hose, struct ar71xx_pci_controller, pci_ctrl); 108 } 109 110 static int ar71xx_pci_check_error(struct ar71xx_pci_controller *apc, int quiet) 111 { 112 void __iomem *base = apc->cfg_base; 113 u32 pci_err; 114 u32 ahb_err; 115 116 pci_err = __raw_readl(base + AR71XX_PCI_REG_PCI_ERR) & 3; 117 if (pci_err) { 118 if (!quiet) { 119 u32 addr; 120 121 addr = __raw_readl(base + AR71XX_PCI_REG_PCI_ERR_ADDR); 122 pr_crit("ar71xx: %s bus error %d at addr 0x%x\n", 123 "PCI", pci_err, addr); 124 } 125 126 /* clear PCI error status */ 127 __raw_writel(pci_err, base + AR71XX_PCI_REG_PCI_ERR); 128 } 129 130 ahb_err = __raw_readl(base + AR71XX_PCI_REG_AHB_ERR) & 1; 131 if (ahb_err) { 132 if (!quiet) { 133 u32 addr; 134 135 addr = __raw_readl(base + AR71XX_PCI_REG_AHB_ERR_ADDR); 136 pr_crit("ar71xx: %s bus error %d at addr 0x%x\n", 137 "AHB", ahb_err, addr); 138 } 139 140 /* clear AHB error status */ 141 __raw_writel(ahb_err, base + AR71XX_PCI_REG_AHB_ERR); 142 } 143 144 return !!(ahb_err | pci_err); 145 } 146 147 static inline void ar71xx_pci_local_write(struct ar71xx_pci_controller *apc, 148 int where, int size, u32 value) 149 { 150 void __iomem *base = apc->cfg_base; 151 u32 ad_cbe; 152 153 value = value << (8 * (where & 3)); 154 155 ad_cbe = AR71XX_PCI_CRP_CMD_WRITE | (where & ~3); 156 ad_cbe |= ar71xx_pci_get_ble(where, size, 1); 157 158 __raw_writel(ad_cbe, base + AR71XX_PCI_REG_CRP_AD_CBE); 159 __raw_writel(value, base + AR71XX_PCI_REG_CRP_WRDATA); 160 } 161 162 static inline int ar71xx_pci_set_cfgaddr(struct pci_bus *bus, 163 unsigned int devfn, 164 int where, int size, u32 cmd) 165 { 166 struct ar71xx_pci_controller *apc = pci_bus_to_ar71xx_controller(bus); 167 void __iomem *base = apc->cfg_base; 168 u32 addr; 169 170 addr = ar71xx_pci_bus_addr(bus, devfn, where); 171 172 __raw_writel(addr, base + AR71XX_PCI_REG_CFG_AD); 173 __raw_writel(cmd | ar71xx_pci_get_ble(where, size, 0), 174 base + AR71XX_PCI_REG_CFG_CBE); 175 176 return ar71xx_pci_check_error(apc, 1); 177 } 178 179 static int ar71xx_pci_read_config(struct pci_bus *bus, unsigned int devfn, 180 int where, int size, u32 *value) 181 { 182 struct ar71xx_pci_controller *apc = pci_bus_to_ar71xx_controller(bus); 183 void __iomem *base = apc->cfg_base; 184 u32 data; 185 int err; 186 int ret; 187 188 ret = PCIBIOS_SUCCESSFUL; 189 data = ~0; 190 191 err = ar71xx_pci_set_cfgaddr(bus, devfn, where, size, 192 AR71XX_PCI_CFG_CMD_READ); 193 if (err) 194 ret = PCIBIOS_DEVICE_NOT_FOUND; 195 else 196 data = __raw_readl(base + AR71XX_PCI_REG_CFG_RDDATA); 197 198 *value = (data >> (8 * (where & 3))) & ar71xx_pci_read_mask[size & 7]; 199 200 return ret; 201 } 202 203 static int ar71xx_pci_write_config(struct pci_bus *bus, unsigned int devfn, 204 int where, int size, u32 value) 205 { 206 struct ar71xx_pci_controller *apc = pci_bus_to_ar71xx_controller(bus); 207 void __iomem *base = apc->cfg_base; 208 int err; 209 int ret; 210 211 value = value << (8 * (where & 3)); 212 ret = PCIBIOS_SUCCESSFUL; 213 214 err = ar71xx_pci_set_cfgaddr(bus, devfn, where, size, 215 AR71XX_PCI_CFG_CMD_WRITE); 216 if (err) 217 ret = PCIBIOS_DEVICE_NOT_FOUND; 218 else 219 __raw_writel(value, base + AR71XX_PCI_REG_CFG_WRDATA); 220 221 return ret; 222 } 223 224 static struct pci_ops ar71xx_pci_ops = { 225 .read = ar71xx_pci_read_config, 226 .write = ar71xx_pci_write_config, 227 }; 228 229 static void ar71xx_pci_irq_handler(unsigned int irq, struct irq_desc *desc) 230 { 231 struct ar71xx_pci_controller *apc; 232 void __iomem *base = ath79_reset_base; 233 u32 pending; 234 235 apc = irq_desc_get_handler_data(desc); 236 237 pending = __raw_readl(base + AR71XX_RESET_REG_PCI_INT_STATUS) & 238 __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE); 239 240 if (pending & AR71XX_PCI_INT_DEV0) 241 generic_handle_irq(apc->irq_base + 0); 242 243 else if (pending & AR71XX_PCI_INT_DEV1) 244 generic_handle_irq(apc->irq_base + 1); 245 246 else if (pending & AR71XX_PCI_INT_DEV2) 247 generic_handle_irq(apc->irq_base + 2); 248 249 else if (pending & AR71XX_PCI_INT_CORE) 250 generic_handle_irq(apc->irq_base + 4); 251 252 else 253 spurious_interrupt(); 254 } 255 256 static void ar71xx_pci_irq_unmask(struct irq_data *d) 257 { 258 struct ar71xx_pci_controller *apc; 259 unsigned int irq; 260 void __iomem *base = ath79_reset_base; 261 u32 t; 262 263 apc = irq_data_get_irq_chip_data(d); 264 irq = d->irq - apc->irq_base; 265 266 t = __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE); 267 __raw_writel(t | (1 << irq), base + AR71XX_RESET_REG_PCI_INT_ENABLE); 268 269 /* flush write */ 270 __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE); 271 } 272 273 static void ar71xx_pci_irq_mask(struct irq_data *d) 274 { 275 struct ar71xx_pci_controller *apc; 276 unsigned int irq; 277 void __iomem *base = ath79_reset_base; 278 u32 t; 279 280 apc = irq_data_get_irq_chip_data(d); 281 irq = d->irq - apc->irq_base; 282 283 t = __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE); 284 __raw_writel(t & ~(1 << irq), base + AR71XX_RESET_REG_PCI_INT_ENABLE); 285 286 /* flush write */ 287 __raw_readl(base + AR71XX_RESET_REG_PCI_INT_ENABLE); 288 } 289 290 static struct irq_chip ar71xx_pci_irq_chip = { 291 .name = "AR71XX PCI", 292 .irq_mask = ar71xx_pci_irq_mask, 293 .irq_unmask = ar71xx_pci_irq_unmask, 294 .irq_mask_ack = ar71xx_pci_irq_mask, 295 }; 296 297 static void ar71xx_pci_irq_init(struct ar71xx_pci_controller *apc) 298 { 299 void __iomem *base = ath79_reset_base; 300 int i; 301 302 __raw_writel(0, base + AR71XX_RESET_REG_PCI_INT_ENABLE); 303 __raw_writel(0, base + AR71XX_RESET_REG_PCI_INT_STATUS); 304 305 BUILD_BUG_ON(ATH79_PCI_IRQ_COUNT < AR71XX_PCI_IRQ_COUNT); 306 307 apc->irq_base = ATH79_PCI_IRQ_BASE; 308 for (i = apc->irq_base; 309 i < apc->irq_base + AR71XX_PCI_IRQ_COUNT; i++) { 310 irq_set_chip_and_handler(i, &ar71xx_pci_irq_chip, 311 handle_level_irq); 312 irq_set_chip_data(i, apc); 313 } 314 315 irq_set_chained_handler_and_data(apc->irq, ar71xx_pci_irq_handler, 316 apc); 317 } 318 319 static void ar71xx_pci_reset(void) 320 { 321 ath79_device_reset_set(AR71XX_RESET_PCI_BUS | AR71XX_RESET_PCI_CORE); 322 mdelay(100); 323 324 ath79_device_reset_clear(AR71XX_RESET_PCI_BUS | AR71XX_RESET_PCI_CORE); 325 mdelay(100); 326 327 ath79_ddr_set_pci_windows(); 328 mdelay(100); 329 } 330 331 static int ar71xx_pci_probe(struct platform_device *pdev) 332 { 333 struct ar71xx_pci_controller *apc; 334 struct resource *res; 335 u32 t; 336 337 apc = devm_kzalloc(&pdev->dev, sizeof(struct ar71xx_pci_controller), 338 GFP_KERNEL); 339 if (!apc) 340 return -ENOMEM; 341 342 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg_base"); 343 apc->cfg_base = devm_ioremap_resource(&pdev->dev, res); 344 if (IS_ERR(apc->cfg_base)) 345 return PTR_ERR(apc->cfg_base); 346 347 apc->irq = platform_get_irq(pdev, 0); 348 if (apc->irq < 0) 349 return -EINVAL; 350 351 res = platform_get_resource_byname(pdev, IORESOURCE_IO, "io_base"); 352 if (!res) 353 return -EINVAL; 354 355 apc->io_res.parent = res; 356 apc->io_res.name = "PCI IO space"; 357 apc->io_res.start = res->start; 358 apc->io_res.end = res->end; 359 apc->io_res.flags = IORESOURCE_IO; 360 361 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mem_base"); 362 if (!res) 363 return -EINVAL; 364 365 apc->mem_res.parent = res; 366 apc->mem_res.name = "PCI memory space"; 367 apc->mem_res.start = res->start; 368 apc->mem_res.end = res->end; 369 apc->mem_res.flags = IORESOURCE_MEM; 370 371 ar71xx_pci_reset(); 372 373 /* setup COMMAND register */ 374 t = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE 375 | PCI_COMMAND_PARITY | PCI_COMMAND_SERR | PCI_COMMAND_FAST_BACK; 376 ar71xx_pci_local_write(apc, PCI_COMMAND, 4, t); 377 378 /* clear bus errors */ 379 ar71xx_pci_check_error(apc, 1); 380 381 ar71xx_pci_irq_init(apc); 382 383 apc->pci_ctrl.pci_ops = &ar71xx_pci_ops; 384 apc->pci_ctrl.mem_resource = &apc->mem_res; 385 apc->pci_ctrl.io_resource = &apc->io_res; 386 387 register_pci_controller(&apc->pci_ctrl); 388 389 return 0; 390 } 391 392 static struct platform_driver ar71xx_pci_driver = { 393 .probe = ar71xx_pci_probe, 394 .driver = { 395 .name = "ar71xx-pci", 396 }, 397 }; 398 399 static int __init ar71xx_pci_init(void) 400 { 401 return platform_driver_register(&ar71xx_pci_driver); 402 } 403 404 postcore_initcall(ar71xx_pci_init); 405