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/*
* linux/arch/arm/mach-integrator/pci-integrator.c
*
* Copyright (C) 1999 ARM Limited
* Copyright (C) 2000 Deep Blue Solutions Ltd
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*
* PCI functions for Integrator
*/
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/ptrace.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <asm/irq.h>
#include <asm/system.h>
#include <asm/mach/pci.h>
/*
* A small note about bridges and interrupts. The DECchip 21050 (and
* later) adheres to the PCI-PCI bridge specification. This says that
* the interrupts on the other side of a bridge are swizzled in the
* following manner:
*
* Dev Interrupt Interrupt
* Pin on Pin on
* Device Connector
*
* 4 A A
* B B
* C C
* D D
*
* 5 A B
* B C
* C D
* D A
*
* 6 A C
* B D
* C A
* D B
*
* 7 A D
* B A
* C B
* D C
*
* Where A = pin 1, B = pin 2 and so on and pin=0 = default = A.
* Thus, each swizzle is ((pin-1) + (device#-4)) % 4
*
* The following code swizzles for exactly one bridge.
*/
static inline int bridge_swizzle(int pin, unsigned int slot)
{
return (pin + slot) & 3;
}
/*
* This routine handles multiple bridges.
*/
static u8 __init integrator_swizzle(struct pci_dev *dev, u8 *pinp)
{
int pin = *pinp;
if (pin == 0)
pin = 1;
pin -= 1;
while (dev->bus->self) {
pin = bridge_swizzle(pin, PCI_SLOT(dev->devfn));
/*
* move up the chain of bridges, swizzling as we go.
*/
dev = dev->bus->self;
}
*pinp = pin + 1;
return PCI_SLOT(dev->devfn);
}
static int irq_tab[4] __initdata = {
IRQ_PCIINT0, IRQ_PCIINT1, IRQ_PCIINT2, IRQ_PCIINT3
};
/*
* map the specified device/slot/pin to an IRQ. This works out such
* that slot 9 pin 1 is INT0, pin 2 is INT1, and slot 10 pin 1 is INT1.
*/
static int __init integrator_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
{
int intnr = ((slot - 9) + (pin - 1)) & 3;
return irq_tab[intnr];
}
extern void pci_v3_setup_resources(struct resource **res);
extern void pci_v3_init(void *);
struct hw_pci integrator_pci __initdata = {
setup_resources: pci_v3_setup_resources,
init: pci_v3_init,
mem_offset: 0x40000000,
swizzle: integrator_swizzle,
map_irq: integrator_map_irq,
};
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