root/arch/arm/mach-footbridge/cats-pci.c

DEFINITIONS

1. cats_no_swizzle
2. cats_map_irq
3. cats_pci_init

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/arch/arm/mach-footbridge/cats-pci.c
   4  *
   5  * PCI bios-type initialisation for PCI machines
   6  *
   7  * Bits taken from various places.
   8  */
   9 #include <linux/kernel.h>
  10 #include <linux/pci.h>
  11 #include <linux/init.h>
  12 
  13 #include <asm/irq.h>
  14 #include <asm/mach/pci.h>
  15 #include <asm/mach-types.h>
  16 
  17 /* cats host-specific stuff */
  18 static int irqmap_cats[] __initdata = { IRQ_PCI, IRQ_IN0, IRQ_IN1, IRQ_IN3 };
  19 
  20 static u8 cats_no_swizzle(struct pci_dev *dev, u8 *pin)
  21 {
  22         return 0;
  23 }
  24 
  25 static int __init cats_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
  26 {
  27         if (dev->irq >= 255)
  28                 return -1;      /* not a valid interrupt. */
  29 
  30         if (dev->irq >= 128)
  31                 return dev->irq & 0x1f;
  32 
  33         if (dev->irq >= 1 && dev->irq <= 4)
  34                 return irqmap_cats[dev->irq - 1];
  35 
  36         if (dev->irq != 0)
  37                 printk("PCI: device %02x:%02x has unknown irq line %x\n",
  38                        dev->bus->number, dev->devfn, dev->irq);
  39 
  40         return -1;
  41 }
  42 
  43 /*
  44  * why not the standard PCI swizzle?  does this prevent 4-port tulip
  45  * cards being used (ie, pci-pci bridge based cards)?
  46  */
  47 static struct hw_pci cats_pci __initdata = {
  48         .swizzle                = cats_no_swizzle,
  49         .map_irq                = cats_map_irq,
  50         .nr_controllers         = 1,
  51         .ops                    = &dc21285_ops,
  52         .setup                  = dc21285_setup,
  53         .preinit                = dc21285_preinit,
  54         .postinit               = dc21285_postinit,
  55 };
  56 
  57 static int __init cats_pci_init(void)
  58 {
  59         if (machine_is_cats())
  60                 pci_common_init(&cats_pci);
  61         return 0;
  62 }
  63 
  64 subsys_initcall(cats_pci_init);