target/linux/ar71xx/files/arch/mips/pci/pci-ar724x.c

   1 /*
   2  *  Atheros AR724x PCI host controller driver
   3  *
   4  *  Copyright (C) 2009-2010 Gabor Juhos <juhosg@openwrt.org>
   5  *
   6  *  Parts of this file are based on Atheros' 2.6.15 BSP
   7  *
   8  *  This program is free software; you can redistribute it and/or modify it
   9  *  under the terms of the GNU General Public License version 2 as published
  10  *  by the Free Software Foundation.
  11  */
  12
  13 #include <linux/resource.h>
  14 #include <linux/types.h>
  15 #include <linux/delay.h>
  16 #include <linux/bitops.h>
  17 #include <linux/pci.h>
  18 #include <linux/pci_regs.h>
  19 #include <linux/interrupt.h>
  20
  21 #include <asm/mach-ar71xx/ar71xx.h>
  22 #include <asm/mach-ar71xx/pci.h>
  23
  24 #undef DEBUG
  25 #ifdef DEBUG
  26 #define DBG(fmt, args...)       printk(KERN_INFO fmt, ## args)
  27 #else
  28 #define DBG(fmt, args...)
  29 #endif
  30
  31 static void __iomem *ar724x_pci_localcfg_base;
  32 static void __iomem *ar724x_pci_devcfg_base;
  33 static void __iomem *ar724x_pci_ctrl_base;
  34 static int ar724x_pci_fixup_enable;
  35
  36 static DEFINE_SPINLOCK(ar724x_pci_lock);
  37
  38 static void ar724x_pci_read(void __iomem *base, int where, int size, u32 *value)
  39 {
  40         unsigned long flags;
  41         u32 data;
  42
  43         spin_lock_irqsave(&ar724x_pci_lock, flags);
  44         data = __raw_readl(base + (where & ~3));
  45
  46         switch (size) {
  47         case 1:
  48                 if (where & 1)
  49                         data >>= 8;
  50                 if (where & 2)
  51                         data >>= 16;
  52                 data &= 0xFF;
  53                 break;
  54         case 2:
  55                 if (where & 2)
  56                         data >>= 16;
  57                 data &= 0xFFFF;
  58                 break;
  59         }
  60
  61         *value = data;
  62         spin_unlock_irqrestore(&ar724x_pci_lock, flags);
  63 }
  64
  65 static void ar724x_pci_write(void __iomem *base, int where, int size, u32 value)
  66 {
  67         unsigned long flags;
  68         u32 data;
  69         int s;
  70
  71         spin_lock_irqsave(&ar724x_pci_lock, flags);
  72         data = __raw_readl(base + (where & ~3));
  73
  74         switch (size) {
  75         case 1:
  76                 s = ((where & 3) << 3);
  77                 data &= ~(0xFF << s);
  78                 data |= ((value & 0xFF) << s);
  79                 break;
  80         case 2:
  81                 s = ((where & 2) << 3);
  82                 data &= ~(0xFFFF << s);
  83                 data |= ((value & 0xFFFF) << s);
  84                 break;
  85         case 4:
  86                 data = value;
  87                 break;
  88         }
  89
  90         __raw_writel(data, base + (where & ~3));
  91         /* flush write */
  92         (void)__raw_readl(base + (where & ~3));
  93         spin_unlock_irqrestore(&ar724x_pci_lock, flags);
  94 }
  95
  96 static int ar724x_pci_read_config(struct pci_bus *bus, unsigned int devfn,
  97                                   int where, int size, u32 *value)
  98 {
  99
 100         if (bus->number != 0 || devfn != 0)
 101                 return PCIBIOS_DEVICE_NOT_FOUND;
 102
 103         ar724x_pci_read(ar724x_pci_devcfg_base, where, size, value);
 104
 105         DBG("PCI: read config: %02x:%02x.%01x/%02x:%01d, value=%08x\n",
 106                         bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn),
 107                         where, size, *value);
 108
 109         /*
 110          * WAR for BAR issue - We are unable to access the PCI device space
 111          * if we set the BAR with proper base address
 112          */
 113         if ((where == 0x10) && (size == 4)) {
 114                 u32 val;
 115                 val = (ar71xx_soc == AR71XX_SOC_AR7240) ? 0xffff : 0x1000ffff;
 116                 ar724x_pci_write(ar724x_pci_devcfg_base, where, size, val);
 117         }
 118
 119         return PCIBIOS_SUCCESSFUL;
 120 }
 121
 122 static int ar724x_pci_write_config(struct pci_bus *bus, unsigned int devfn,
 123                                    int where, int size, u32 value)
 124 {
 125         if (bus->number != 0 || devfn != 0)
 126                 return PCIBIOS_DEVICE_NOT_FOUND;
 127
 128         DBG("PCI: write config: %02x:%02x.%01x/%02x:%01d, value=%08x\n",
 129                 bus->number, PCI_SLOT(devfn), PCI_FUNC(devfn),
 130                 where, size, value);
 131
 132         ar724x_pci_write(ar724x_pci_devcfg_base, where, size, value);
 133
 134         return PCIBIOS_SUCCESSFUL;
 135 }
 136
 137 static void ar724x_pci_fixup(struct pci_dev *dev)
 138 {
 139         u16 cmd;
 140
 141         if (!ar724x_pci_fixup_enable)
 142                 return;
 143
 144         if (dev->bus->number != 0 || dev->devfn != 0)
 145                 return;
 146
 147         /* setup COMMAND register */
 148         pci_read_config_word(dev, PCI_COMMAND, &cmd);
 149         cmd |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
 150                PCI_COMMAND_INVALIDATE | PCI_COMMAND_PARITY | PCI_COMMAND_SERR |
 151                PCI_COMMAND_FAST_BACK;
 152
 153         pci_write_config_word(dev, PCI_COMMAND, cmd);
 154 }
 155 DECLARE_PCI_FIXUP_EARLY(PCI_ANY_ID, PCI_ANY_ID, ar724x_pci_fixup);
 156
 157 int __init ar724x_pcibios_map_irq(const struct pci_dev *dev, uint8_t slot,
 158                                   uint8_t pin)
 159 {
 160         int irq = -1;
 161         int i;
 162
 163         for (i = 0; i < ar71xx_pci_nr_irqs; i++) {
 164                 struct ar71xx_pci_irq *entry;
 165                 entry = &ar71xx_pci_irq_map[i];
 166
 167                 if (entry->slot == slot && entry->pin == pin) {
 168                         irq = entry->irq;
 169                         break;
 170                 }
 171         }
 172
 173         if (irq < 0)
 174                 printk(KERN_ALERT "PCI: no irq found for pin%u@%s\n",
 175                                 pin, pci_name((struct pci_dev *)dev));
 176         else
 177                 printk(KERN_INFO "PCI: mapping irq %d to pin%u@%s\n",
 178                                 irq, pin, pci_name((struct pci_dev *)dev));
 179
 180         return irq;
 181 }
 182
 183 static struct pci_ops ar724x_pci_ops = {
 184         .read   = ar724x_pci_read_config,
 185         .write  = ar724x_pci_write_config,
 186 };
 187
 188 static struct resource ar724x_pci_io_resource = {
 189         .name           = "PCI IO space",
 190         .start          = 0,
 191         .end            = 0,
 192         .flags          = IORESOURCE_IO,
 193 };
 194
 195 static struct resource ar724x_pci_mem_resource = {
 196         .name           = "PCI memory space",
 197         .start          = AR71XX_PCI_MEM_BASE,
 198         .end            = AR71XX_PCI_MEM_BASE + AR71XX_PCI_MEM_SIZE - 1,
 199         .flags          = IORESOURCE_MEM
 200 };
 201
 202 static struct pci_controller ar724x_pci_controller = {
 203         .pci_ops        = &ar724x_pci_ops,
 204         .mem_resource   = &ar724x_pci_mem_resource,
 205         .io_resource    = &ar724x_pci_io_resource,
 206 };
 207
 208 static void __init ar724x_pci_reset(void)
 209 {
 210         ar71xx_device_stop(AR724X_RESET_PCIE);
 211         ar71xx_device_stop(AR724X_RESET_PCIE_PHY);
 212         ar71xx_device_stop(AR724X_RESET_PCIE_PHY_SERIAL);
 213         udelay(100);
 214
 215         ar71xx_device_start(AR724X_RESET_PCIE_PHY_SERIAL);
 216         udelay(100);
 217         ar71xx_device_start(AR724X_RESET_PCIE_PHY);
 218         ar71xx_device_start(AR724X_RESET_PCIE);
 219 }
 220
 221 static int __init ar724x_pci_setup(void)
 222 {
 223         void __iomem *base = ar724x_pci_ctrl_base;
 224         u32 t;
 225
 226         /* setup COMMAND register */
 227         t = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE |
 228             PCI_COMMAND_PARITY|PCI_COMMAND_SERR|PCI_COMMAND_FAST_BACK;
 229
 230         ar724x_pci_write(ar724x_pci_localcfg_base, PCI_COMMAND, 4, t);
 231         ar724x_pci_write(ar724x_pci_localcfg_base, 0x20, 4, 0x1ff01000);
 232         ar724x_pci_write(ar724x_pci_localcfg_base, 0x24, 4, 0x1ff01000);
 233
 234         t = __raw_readl(base + AR724X_PCI_REG_RESET);
 235         if (t != 0x7) {
 236                 udelay(100000);
 237                 __raw_writel(0, base + AR724X_PCI_REG_RESET);
 238                 udelay(100);
 239                 __raw_writel(4, base + AR724X_PCI_REG_RESET);
 240                 udelay(100000);
 241         }
 242
 243         if (ar71xx_soc == AR71XX_SOC_AR7240)
 244                 t = AR724X_PCI_APP_LTSSM_ENABLE;
 245         else
 246                 t = 0x1ffc1;
 247         __raw_writel(t, base + AR724X_PCI_REG_APP);
 248         /* flush write */
 249         (void) __raw_readl(base + AR724X_PCI_REG_APP);
 250         udelay(1000);
 251
 252         t = __raw_readl(base + AR724X_PCI_REG_RESET);
 253         if ((t & AR724X_PCI_RESET_LINK_UP) == 0x0) {
 254                 printk(KERN_WARNING "PCI: no PCIe module found\n");
 255                 return -ENODEV;
 256         }
 257
 258         if (ar71xx_soc == AR71XX_SOC_AR7241 ||
 259             ar71xx_soc == AR71XX_SOC_AR7242) {
 260                 t = __raw_readl(base + AR724X_PCI_REG_APP);
 261                 t |= BIT(16);
 262                 __raw_writel(t, base + AR724X_PCI_REG_APP);
 263         }
 264
 265         return 0;
 266 }
 267
 268 static void ar724x_pci_irq_handler(unsigned int irq, struct irq_desc *desc)
 269 {
 270         void __iomem *base = ar724x_pci_ctrl_base;
 271         u32 pending;
 272
 273         pending = __raw_readl(base + AR724X_PCI_REG_INT_STATUS) &
 274                   __raw_readl(base + AR724X_PCI_REG_INT_MASK);
 275
 276         if (pending & AR724X_PCI_INT_DEV0)
 277                 generic_handle_irq(AR71XX_PCI_IRQ_DEV0);
 278
 279         else
 280                 spurious_interrupt();
 281 }
 282
 283 static void ar724x_pci_irq_unmask(unsigned int irq)
 284 {
 285         void __iomem *base = ar724x_pci_ctrl_base;
 286         u32 t;
 287
 288         switch (irq) {
 289         case AR71XX_PCI_IRQ_DEV0:
 290                 irq -= AR71XX_PCI_IRQ_BASE;
 291
 292                 t = __raw_readl(base + AR724X_PCI_REG_INT_MASK);
 293                 __raw_writel(t | AR724X_PCI_INT_DEV0,
 294                              base + AR724X_PCI_REG_INT_MASK);
 295                 /* flush write */
 296                 (void) __raw_readl(base + AR724X_PCI_REG_INT_MASK);
 297         }
 298 }
 299
 300 static void ar724x_pci_irq_mask(unsigned int irq)
 301 {
 302         void __iomem *base = ar724x_pci_ctrl_base;
 303         u32 t;
 304
 305         switch (irq) {
 306         case AR71XX_PCI_IRQ_DEV0:
 307                 irq -= AR71XX_PCI_IRQ_BASE;
 308
 309                 t = __raw_readl(base + AR724X_PCI_REG_INT_MASK);
 310                 __raw_writel(t & ~AR724X_PCI_INT_DEV0,
 311                              base + AR724X_PCI_REG_INT_MASK);
 312
 313                 /* flush write */
 314                 (void) __raw_readl(base + AR724X_PCI_REG_INT_MASK);
 315
 316                 t = __raw_readl(base + AR724X_PCI_REG_INT_STATUS);
 317                 __raw_writel(t | AR724X_PCI_INT_DEV0,
 318                              base + AR724X_PCI_REG_INT_STATUS);
 319
 320                 /* flush write */
 321                 (void) __raw_readl(base + AR724X_PCI_REG_INT_STATUS);
 322         }
 323 }
 324
 325 static struct irq_chip ar724x_pci_irq_chip = {
 326         .name           = "AR724X PCI ",
 327         .mask           = ar724x_pci_irq_mask,
 328         .unmask         = ar724x_pci_irq_unmask,
 329         .mask_ack       = ar724x_pci_irq_mask,
 330 };
 331
 332 static void __init ar724x_pci_irq_init(void)
 333 {
 334         void __iomem *base = ar724x_pci_ctrl_base;
 335         u32 t;
 336         int i;
 337
 338         t = ar71xx_reset_rr(AR724X_RESET_REG_RESET_MODULE);
 339         if (t & (AR724X_RESET_PCIE | AR724X_RESET_PCIE_PHY |
 340                  AR724X_RESET_PCIE_PHY_SERIAL)) {
 341                 return;
 342         }
 343
 344         __raw_writel(0, base + AR724X_PCI_REG_INT_MASK);
 345         __raw_writel(0, base + AR724X_PCI_REG_INT_STATUS);
 346
 347         for (i = AR71XX_PCI_IRQ_BASE;
 348              i < AR71XX_PCI_IRQ_BASE + AR71XX_PCI_IRQ_COUNT; i++)
 349                 set_irq_chip_and_handler(i, &ar724x_pci_irq_chip,
 350                                          handle_level_irq);
 351
 352         set_irq_chained_handler(AR71XX_CPU_IRQ_IP2, ar724x_pci_irq_handler);
 353 }
 354
 355 int __init ar724x_pcibios_init(void)
 356 {
 357         int ret = -ENOMEM;
 358
 359         ar724x_pci_localcfg_base = ioremap_nocache(AR724X_PCI_CRP_BASE,
 360                                                    AR724X_PCI_CRP_SIZE);
 361         if (ar724x_pci_localcfg_base == NULL)
 362                 goto err;
 363
 364         ar724x_pci_devcfg_base = ioremap_nocache(AR724X_PCI_CFG_BASE,
 365                                                  AR724X_PCI_CFG_SIZE);
 366         if (ar724x_pci_devcfg_base == NULL)
 367                 goto err_unmap_localcfg;
 368
 369         ar724x_pci_ctrl_base = ioremap_nocache(AR724X_PCI_CTRL_BASE,
 370                                                AR724X_PCI_CTRL_SIZE);
 371         if (ar724x_pci_ctrl_base == NULL)
 372                 goto err_unmap_devcfg;
 373
 374         ar724x_pci_reset();
 375         ret = ar724x_pci_setup();
 376         if (ret)
 377                 goto err_unmap_ctrl;
 378
 379         ar724x_pci_fixup_enable = 1;
 380         ar724x_pci_irq_init();
 381         register_pci_controller(&ar724x_pci_controller);
 382
 383         return 0;
 384
 385 err_unmap_ctrl:
 386         iounmap(ar724x_pci_ctrl_base);
 387 err_unmap_devcfg:
 388         iounmap(ar724x_pci_devcfg_base);
 389 err_unmap_localcfg:
 390         iounmap(ar724x_pci_localcfg_base);
 391 err:
 392         return ret;
 393 }