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   1 /*
   2  * arch/arm/mach-ixp2000/core.c
   3  *
   4  * Common routines used by all IXP2400/2800 based platforms.
   5  *
   6  * Author: Deepak Saxena <dsaxena@plexity.net>
   7  *
   8  * Copyright 2004 (C) MontaVista Software, Inc.
   9  *
  10  * Based on work Copyright (C) 2002-2003 Intel Corporation
  11  *
  12  * This file is licensed under the terms of the GNU General Public
  13  * License version 2. This program is licensed "as is" without any
  14  * warranty of any kind, whether express or implied.
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/init.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/sched.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/irq.h>
  23 #include <linux/serial.h>
  24 #include <linux/tty.h>
  25 #include <linux/bitops.h>
  26 #include <linux/serial_8250.h>
  27 #include <linux/mm.h>
  28
  29 #include <asm/types.h>
  30 #include <asm/setup.h>
  31 #include <asm/memory.h>
  32 #include <mach/hardware.h>
  33 #include <asm/irq.h>
  34 #include <asm/system.h>
  35 #include <asm/tlbflush.h>
  36 #include <asm/pgtable.h>
  37
  38 #include <asm/mach/map.h>
  39 #include <asm/mach/time.h>
  40 #include <asm/mach/irq.h>
  41
  42 #include <mach/gpio.h>
  43
  44 static DEFINE_SPINLOCK(ixp2000_slowport_lock);
  45 static unsigned long ixp2000_slowport_irq_flags;
  46
  47 /*************************************************************************
  48  * Slowport access routines
  49  *************************************************************************/
  50 void ixp2000_acquire_slowport(struct slowport_cfg *new_cfg, struct slowport_cfg *old_cfg)
  51 {
  52         spin_lock_irqsave(&ixp2000_slowport_lock, ixp2000_slowport_irq_flags);
  53
  54         old_cfg->CCR = *IXP2000_SLOWPORT_CCR;
  55         old_cfg->WTC = *IXP2000_SLOWPORT_WTC2;
  56         old_cfg->RTC = *IXP2000_SLOWPORT_RTC2;
  57         old_cfg->PCR = *IXP2000_SLOWPORT_PCR;
  58         old_cfg->ADC = *IXP2000_SLOWPORT_ADC;
  59
  60         ixp2000_reg_write(IXP2000_SLOWPORT_CCR, new_cfg->CCR);
  61         ixp2000_reg_write(IXP2000_SLOWPORT_WTC2, new_cfg->WTC);
  62         ixp2000_reg_write(IXP2000_SLOWPORT_RTC2, new_cfg->RTC);
  63         ixp2000_reg_write(IXP2000_SLOWPORT_PCR, new_cfg->PCR);
  64         ixp2000_reg_wrb(IXP2000_SLOWPORT_ADC, new_cfg->ADC);
  65 }
  66
  67 void ixp2000_release_slowport(struct slowport_cfg *old_cfg)
  68 {
  69         ixp2000_reg_write(IXP2000_SLOWPORT_CCR, old_cfg->CCR);
  70         ixp2000_reg_write(IXP2000_SLOWPORT_WTC2, old_cfg->WTC);
  71         ixp2000_reg_write(IXP2000_SLOWPORT_RTC2, old_cfg->RTC);
  72         ixp2000_reg_write(IXP2000_SLOWPORT_PCR, old_cfg->PCR);
  73         ixp2000_reg_wrb(IXP2000_SLOWPORT_ADC, old_cfg->ADC);
  74
  75         spin_unlock_irqrestore(&ixp2000_slowport_lock,
  76                                         ixp2000_slowport_irq_flags);
  77 }
  78
  79 /*************************************************************************
  80  * Chip specific mappings shared by all IXP2000 systems
  81  *************************************************************************/
  82 static struct map_desc ixp2000_io_desc[] __initdata = {
  83         {
  84                 .virtual        = IXP2000_CAP_VIRT_BASE,
  85                 .pfn            = __phys_to_pfn(IXP2000_CAP_PHYS_BASE),
  86                 .length         = IXP2000_CAP_SIZE,
  87                 .type           = MT_DEVICE_IXP2000,
  88         }, {
  89                 .virtual        = IXP2000_INTCTL_VIRT_BASE,
  90                 .pfn            = __phys_to_pfn(IXP2000_INTCTL_PHYS_BASE),
  91                 .length         = IXP2000_INTCTL_SIZE,
  92                 .type           = MT_DEVICE_IXP2000,
  93         }, {
  94                 .virtual        = IXP2000_PCI_CREG_VIRT_BASE,
  95                 .pfn            = __phys_to_pfn(IXP2000_PCI_CREG_PHYS_BASE),
  96                 .length         = IXP2000_PCI_CREG_SIZE,
  97                 .type           = MT_DEVICE_IXP2000,
  98         }, {
  99                 .virtual        = IXP2000_PCI_CSR_VIRT_BASE,
 100                 .pfn            = __phys_to_pfn(IXP2000_PCI_CSR_PHYS_BASE),
 101                 .length         = IXP2000_PCI_CSR_SIZE,
 102                 .type           = MT_DEVICE_IXP2000,
 103         }, {
 104                 .virtual        = IXP2000_MSF_VIRT_BASE,
 105                 .pfn            = __phys_to_pfn(IXP2000_MSF_PHYS_BASE),
 106                 .length         = IXP2000_MSF_SIZE,
 107                 .type           = MT_DEVICE_IXP2000,
 108         }, {
 109                 .virtual        = IXP2000_SCRATCH_RING_VIRT_BASE,
 110                 .pfn            = __phys_to_pfn(IXP2000_SCRATCH_RING_PHYS_BASE),
 111                 .length         = IXP2000_SCRATCH_RING_SIZE,
 112                 .type           = MT_DEVICE_IXP2000,
 113         }, {
 114                 .virtual        = IXP2000_SRAM0_VIRT_BASE,
 115                 .pfn            = __phys_to_pfn(IXP2000_SRAM0_PHYS_BASE),
 116                 .length         = IXP2000_SRAM0_SIZE,
 117                 .type           = MT_DEVICE_IXP2000,
 118         }, {
 119                 .virtual        = IXP2000_PCI_IO_VIRT_BASE,
 120                 .pfn            = __phys_to_pfn(IXP2000_PCI_IO_PHYS_BASE),
 121                 .length         = IXP2000_PCI_IO_SIZE,
 122                 .type           = MT_DEVICE_IXP2000,
 123         }, {
 124                 .virtual        = IXP2000_PCI_CFG0_VIRT_BASE,
 125                 .pfn            = __phys_to_pfn(IXP2000_PCI_CFG0_PHYS_BASE),
 126                 .length         = IXP2000_PCI_CFG0_SIZE,
 127                 .type           = MT_DEVICE_IXP2000,
 128         }, {
 129                 .virtual        = IXP2000_PCI_CFG1_VIRT_BASE,
 130                 .pfn            = __phys_to_pfn(IXP2000_PCI_CFG1_PHYS_BASE),
 131                 .length         = IXP2000_PCI_CFG1_SIZE,
 132                 .type           = MT_DEVICE_IXP2000,
 133         }
 134 };
 135
 136 void __init ixp2000_map_io(void)
 137 {
 138         /*
 139          * On IXP2400 CPUs we need to use MT_DEVICE_IXP2000 so that
 140          * XCB=101 (to avoid triggering erratum #66), and given that
 141          * this mode speeds up I/O accesses and we have write buffer
 142          * flushes in the right places anyway, it doesn't hurt to use
 143          * XCB=101 for all IXP2000s.
 144          */
 145         iotable_init(ixp2000_io_desc, ARRAY_SIZE(ixp2000_io_desc));
 146
 147         /* Set slowport to 8-bit mode.  */
 148         ixp2000_reg_wrb(IXP2000_SLOWPORT_FRM, 1);
 149 }
 150
 151
 152 /*************************************************************************
 153  * Serial port support for IXP2000
 154  *************************************************************************/
 155 static struct plat_serial8250_port ixp2000_serial_port[] = {
 156         {
 157                 .mapbase        = IXP2000_UART_PHYS_BASE,
 158                 .membase        = (char *)(IXP2000_UART_VIRT_BASE + 3),
 159                 .irq            = IRQ_IXP2000_UART,
 160                 .flags          = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
 161                 .iotype         = UPIO_MEM,
 162                 .regshift       = 2,
 163                 .uartclk        = 50000000,
 164         },
 165         { },
 166 };
 167
 168 static struct resource ixp2000_uart_resource = {
 169         .start          = IXP2000_UART_PHYS_BASE,
 170         .end            = IXP2000_UART_PHYS_BASE + 0x1f,
 171         .flags          = IORESOURCE_MEM,
 172 };
 173
 174 static struct platform_device ixp2000_serial_device = {
 175         .name           = "serial8250",
 176         .id             = PLAT8250_DEV_PLATFORM,
 177         .dev            = {
 178                 .platform_data          = ixp2000_serial_port,
 179         },
 180         .num_resources  = 1,
 181         .resource       = &ixp2000_uart_resource,
 182 };
 183
 184 void __init ixp2000_uart_init(void)
 185 {
 186         platform_device_register(&ixp2000_serial_device);
 187 }
 188
 189
 190 /*************************************************************************
 191  * Timer-tick functions for IXP2000
 192  *************************************************************************/
 193 static unsigned ticks_per_jiffy;
 194 static unsigned ticks_per_usec;
 195 static unsigned next_jiffy_time;
 196 static volatile unsigned long *missing_jiffy_timer_csr;
 197
 198 unsigned long ixp2000_gettimeoffset (void)
 199 {
 200         unsigned long offset;
 201
 202         offset = next_jiffy_time - *missing_jiffy_timer_csr;
 203
 204         return offset / ticks_per_usec;
 205 }
 206
 207 static int ixp2000_timer_interrupt(int irq, void *dev_id)
 208 {
 209         /* clear timer 1 */
 210         ixp2000_reg_wrb(IXP2000_T1_CLR, 1);
 211
 212         while ((signed long)(next_jiffy_time - *missing_jiffy_timer_csr)
 213                                                         >= ticks_per_jiffy) {
 214                 timer_tick();
 215                 next_jiffy_time -= ticks_per_jiffy;
 216         }
 217
 218         return IRQ_HANDLED;
 219 }
 220
 221 static struct irqaction ixp2000_timer_irq = {
 222         .name           = "IXP2000 Timer Tick",
 223         .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
 224         .handler        = ixp2000_timer_interrupt,
 225 };
 226
 227 void __init ixp2000_init_time(unsigned long tick_rate)
 228 {
 229         ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
 230         ticks_per_usec = tick_rate / 1000000;
 231
 232         /*
 233          * We use timer 1 as our timer interrupt.
 234          */
 235         ixp2000_reg_write(IXP2000_T1_CLR, 0);
 236         ixp2000_reg_write(IXP2000_T1_CLD, ticks_per_jiffy - 1);
 237         ixp2000_reg_write(IXP2000_T1_CTL, (1 << 7));
 238
 239         /*
 240          * We use a second timer as a monotonic counter for tracking
 241          * missed jiffies.  The IXP2000 has four timers, but if we're
 242          * on an A-step IXP2800, timer 2 and 3 don't work, so on those
 243          * chips we use timer 4.  Timer 4 is the only timer that can
 244          * be used for the watchdog, so we use timer 2 if we're on a
 245          * non-buggy chip.
 246          */
 247         if ((*IXP2000_PRODUCT_ID & 0x001ffef0) == 0x00000000) {
 248                 printk(KERN_INFO "Enabling IXP2800 erratum #25 workaround\n");
 249
 250                 ixp2000_reg_write(IXP2000_T4_CLR, 0);
 251                 ixp2000_reg_write(IXP2000_T4_CLD, -1);
 252                 ixp2000_reg_wrb(IXP2000_T4_CTL, (1 << 7));
 253                 missing_jiffy_timer_csr = IXP2000_T4_CSR;
 254         } else {
 255                 ixp2000_reg_write(IXP2000_T2_CLR, 0);
 256                 ixp2000_reg_write(IXP2000_T2_CLD, -1);
 257                 ixp2000_reg_wrb(IXP2000_T2_CTL, (1 << 7));
 258                 missing_jiffy_timer_csr = IXP2000_T2_CSR;
 259         }
 260         next_jiffy_time = 0xffffffff;
 261
 262         /* register for interrupt */
 263         setup_irq(IRQ_IXP2000_TIMER1, &ixp2000_timer_irq);
 264 }
 265
 266 /*************************************************************************
 267  * GPIO helpers
 268  *************************************************************************/
 269 static unsigned long GPIO_IRQ_falling_edge;
 270 static unsigned long GPIO_IRQ_rising_edge;
 271 static unsigned long GPIO_IRQ_level_low;
 272 static unsigned long GPIO_IRQ_level_high;
 273
 274 static void update_gpio_int_csrs(void)
 275 {
 276         ixp2000_reg_write(IXP2000_GPIO_FEDR, GPIO_IRQ_falling_edge);
 277         ixp2000_reg_write(IXP2000_GPIO_REDR, GPIO_IRQ_rising_edge);
 278         ixp2000_reg_write(IXP2000_GPIO_LSLR, GPIO_IRQ_level_low);
 279         ixp2000_reg_wrb(IXP2000_GPIO_LSHR, GPIO_IRQ_level_high);
 280 }
 281
 282 void gpio_line_config(int line, int direction)
 283 {
 284         unsigned long flags;
 285
 286         local_irq_save(flags);
 287         if (direction == GPIO_OUT) {
 288                 /* if it's an output, it ain't an interrupt anymore */
 289                 GPIO_IRQ_falling_edge &= ~(1 << line);
 290                 GPIO_IRQ_rising_edge &= ~(1 << line);
 291                 GPIO_IRQ_level_low &= ~(1 << line);
 292                 GPIO_IRQ_level_high &= ~(1 << line);
 293                 update_gpio_int_csrs();
 294
 295                 ixp2000_reg_wrb(IXP2000_GPIO_PDSR, 1 << line);
 296         } else if (direction == GPIO_IN) {
 297                 ixp2000_reg_wrb(IXP2000_GPIO_PDCR, 1 << line);
 298         }
 299         local_irq_restore(flags);
 300 }
 301 EXPORT_SYMBOL(gpio_line_config);
 302
 303
 304 /*************************************************************************
 305  * IRQ handling IXP2000
 306  *************************************************************************/
 307 static void ixp2000_GPIO_irq_handler(unsigned int irq, struct irq_desc *desc)
 308 {
 309         int i;
 310         unsigned long status = *IXP2000_GPIO_INST;
 311
 312         for (i = 0; i <= 7; i++) {
 313                 if (status & (1<<i)) {
 314                         desc = irq_desc + i + IRQ_IXP2000_GPIO0;
 315                         desc_handle_irq(i + IRQ_IXP2000_GPIO0, desc);
 316                 }
 317         }
 318 }
 319
 320 static int ixp2000_GPIO_irq_type(unsigned int irq, unsigned int type)
 321 {
 322         int line = irq - IRQ_IXP2000_GPIO0;
 323
 324         /*
 325          * First, configure this GPIO line as an input.
 326          */
 327         ixp2000_reg_write(IXP2000_GPIO_PDCR, 1 << line);
 328
 329         /*
 330          * Then, set the proper trigger type.
 331          */
 332         if (type & IRQ_TYPE_EDGE_FALLING)
 333                 GPIO_IRQ_falling_edge |= 1 << line;
 334         else
 335                 GPIO_IRQ_falling_edge &= ~(1 << line);
 336         if (type & IRQ_TYPE_EDGE_RISING)
 337                 GPIO_IRQ_rising_edge |= 1 << line;
 338         else
 339                 GPIO_IRQ_rising_edge &= ~(1 << line);
 340         if (type & IRQ_TYPE_LEVEL_LOW)
 341                 GPIO_IRQ_level_low |= 1 << line;
 342         else
 343                 GPIO_IRQ_level_low &= ~(1 << line);
 344         if (type & IRQ_TYPE_LEVEL_HIGH)
 345                 GPIO_IRQ_level_high |= 1 << line;
 346         else
 347                 GPIO_IRQ_level_high &= ~(1 << line);
 348         update_gpio_int_csrs();
 349
 350         return 0;
 351 }
 352
 353 static void ixp2000_GPIO_irq_mask_ack(unsigned int irq)
 354 {
 355         ixp2000_reg_write(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 356
 357         ixp2000_reg_write(IXP2000_GPIO_EDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 358         ixp2000_reg_write(IXP2000_GPIO_LDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 359         ixp2000_reg_wrb(IXP2000_GPIO_INST, (1 << (irq - IRQ_IXP2000_GPIO0)));
 360 }
 361
 362 static void ixp2000_GPIO_irq_mask(unsigned int irq)
 363 {
 364         ixp2000_reg_wrb(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 365 }
 366
 367 static void ixp2000_GPIO_irq_unmask(unsigned int irq)
 368 {
 369         ixp2000_reg_write(IXP2000_GPIO_INSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
 370 }
 371
 372 static struct irq_chip ixp2000_GPIO_irq_chip = {
 373         .ack            = ixp2000_GPIO_irq_mask_ack,
 374         .mask           = ixp2000_GPIO_irq_mask,
 375         .unmask         = ixp2000_GPIO_irq_unmask,
 376         .set_type       = ixp2000_GPIO_irq_type,
 377 };
 378
 379 static void ixp2000_pci_irq_mask(unsigned int irq)
 380 {
 381         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
 382         if (irq == IRQ_IXP2000_PCIA)
 383                 ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 26)));
 384         else if (irq == IRQ_IXP2000_PCIB)
 385                 ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 27)));
 386 }
 387
 388 static void ixp2000_pci_irq_unmask(unsigned int irq)
 389 {
 390         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
 391         if (irq == IRQ_IXP2000_PCIA)
 392                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 26)));
 393         else if (irq == IRQ_IXP2000_PCIB)
 394                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 27)));
 395 }
 396
 397 /*
 398  * Error interrupts. These are used extensively by the microengine drivers
 399  */
 400 static void ixp2000_err_irq_handler(unsigned int irq, struct irq_desc *desc)
 401 {
 402         int i;
 403         unsigned long status = *IXP2000_IRQ_ERR_STATUS;
 404
 405         for(i = 31; i >= 0; i--) {
 406                 if(status & (1 << i)) {
 407                         desc = irq_desc + IRQ_IXP2000_DRAM0_MIN_ERR + i;
 408                         desc_handle_irq(IRQ_IXP2000_DRAM0_MIN_ERR + i, desc);
 409                 }
 410         }
 411 }
 412
 413 static void ixp2000_err_irq_mask(unsigned int irq)
 414 {
 415         ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_CLR,
 416                         (1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
 417 }
 418
 419 static void ixp2000_err_irq_unmask(unsigned int irq)
 420 {
 421         ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_SET,
 422                         (1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
 423 }
 424
 425 static struct irq_chip ixp2000_err_irq_chip = {
 426         .ack    = ixp2000_err_irq_mask,
 427         .mask   = ixp2000_err_irq_mask,
 428         .unmask = ixp2000_err_irq_unmask
 429 };
 430
 431 static struct irq_chip ixp2000_pci_irq_chip = {
 432         .ack    = ixp2000_pci_irq_mask,
 433         .mask   = ixp2000_pci_irq_mask,
 434         .unmask = ixp2000_pci_irq_unmask
 435 };
 436
 437 static void ixp2000_irq_mask(unsigned int irq)
 438 {
 439         ixp2000_reg_wrb(IXP2000_IRQ_ENABLE_CLR, (1 << irq));
 440 }
 441
 442 static void ixp2000_irq_unmask(unsigned int irq)
 443 {
 444         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << irq));
 445 }
 446
 447 static struct irq_chip ixp2000_irq_chip = {
 448         .ack    = ixp2000_irq_mask,
 449         .mask   = ixp2000_irq_mask,
 450         .unmask = ixp2000_irq_unmask
 451 };
 452
 453 void __init ixp2000_init_irq(void)
 454 {
 455         int irq;
 456
 457         /*
 458          * Mask all sources
 459          */
 460         ixp2000_reg_write(IXP2000_IRQ_ENABLE_CLR, 0xffffffff);
 461         ixp2000_reg_write(IXP2000_FIQ_ENABLE_CLR, 0xffffffff);
 462
 463         /* clear all GPIO edge/level detects */
 464         ixp2000_reg_write(IXP2000_GPIO_REDR, 0);
 465         ixp2000_reg_write(IXP2000_GPIO_FEDR, 0);
 466         ixp2000_reg_write(IXP2000_GPIO_LSHR, 0);
 467         ixp2000_reg_write(IXP2000_GPIO_LSLR, 0);
 468         ixp2000_reg_write(IXP2000_GPIO_INCR, -1);
 469
 470         /* clear PCI interrupt sources */
 471         ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, 0);
 472
 473         /*
 474          * Certain bits in the IRQ status register of the
 475          * IXP2000 are reserved. Instead of trying to map
 476          * things non 1:1 from bit position to IRQ number,
 477          * we mark the reserved IRQs as invalid. This makes
 478          * our mask/unmask code much simpler.
 479          */
 480         for (irq = IRQ_IXP2000_SOFT_INT; irq <= IRQ_IXP2000_THDB3; irq++) {
 481                 if ((1 << irq) & IXP2000_VALID_IRQ_MASK) {
 482                         set_irq_chip(irq, &ixp2000_irq_chip);
 483                         set_irq_handler(irq, handle_level_irq);
 484                         set_irq_flags(irq, IRQF_VALID);
 485                 } else set_irq_flags(irq, 0);
 486         }
 487
 488         for (irq = IRQ_IXP2000_DRAM0_MIN_ERR; irq <= IRQ_IXP2000_SP_INT; irq++) {
 489                 if((1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)) &
 490                                 IXP2000_VALID_ERR_IRQ_MASK) {
 491                         set_irq_chip(irq, &ixp2000_err_irq_chip);
 492                         set_irq_handler(irq, handle_level_irq);
 493                         set_irq_flags(irq, IRQF_VALID);
 494                 }
 495                 else
 496                         set_irq_flags(irq, 0);
 497         }
 498         set_irq_chained_handler(IRQ_IXP2000_ERRSUM, ixp2000_err_irq_handler);
 499
 500         for (irq = IRQ_IXP2000_GPIO0; irq <= IRQ_IXP2000_GPIO7; irq++) {
 501                 set_irq_chip(irq, &ixp2000_GPIO_irq_chip);
 502                 set_irq_handler(irq, handle_level_irq);
 503                 set_irq_flags(irq, IRQF_VALID);
 504         }
 505         set_irq_chained_handler(IRQ_IXP2000_GPIO, ixp2000_GPIO_irq_handler);
 506
 507         /*
 508          * Enable PCI irqs.  The actual PCI[AB] decoding is done in
 509          * entry-macro.S, so we don't need a chained handler for the
 510          * PCI interrupt source.
 511          */
 512         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << IRQ_IXP2000_PCI));
 513         for (irq = IRQ_IXP2000_PCIA; irq <= IRQ_IXP2000_PCIB; irq++) {
 514                 set_irq_chip(irq, &ixp2000_pci_irq_chip);
 515                 set_irq_handler(irq, handle_level_irq);
 516                 set_irq_flags(irq, IRQF_VALID);
 517         }
 518 }
 519