pmac_pci.c

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/*
 * Support for PCI bridges found on Power Macintoshes.
 * At present the "bandit" and "chaos" bridges are supported.
 * Fortunately you access configuration space in the same
 * way with either bridge.
 *
 * Copyright (C) 1997 Paul Mackerras ([e-mail])
 *
 * 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.
 */

#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>

#include <asm/init.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/machdep.h>

#include "pci.h"

struct bridge_data **bridges, *bridge_list;
static int max_bus;

struct uninorth_data {
	struct device_node*	node;
	volatile unsigned int*	cfg_addr;
	volatile unsigned int*	cfg_data;
	void*			iobase;
	unsigned long		iobase_phys;
};

static struct uninorth_data uninorth_bridges[3];
static int uninorth_count;
static int uninorth_default = -1;

static void add_bridges(struct device_node *dev);

/*
 * Magic constants for enabling cache coherency in the bandit/PSX bridge.
 */
#define APPLE_VENDID	0x106b
#define BANDIT_DEVID	1
#define BANDIT_DEVID_2	8
#define BANDIT_REVID	3

#define BANDIT_DEVNUM	11
#define BANDIT_MAGIC	0x50
#define BANDIT_COHERENT	0x40

/* Obsolete, should be replaced by pmac_pci_dev_io_base() (below) */
__pmac
void *pci_io_base(unsigned int bus)
{
	struct bridge_data *bp;

	if (bus > max_bus || (bp = bridges[bus]) == 0)
		return 0;
	return bp->io_base;
}

__pmac
int pci_device_loc(struct device_node *dev, unsigned char *bus_ptr,
		   unsigned char *devfn_ptr)
{
	unsigned int *reg;
	int len;

	reg = (unsigned int *) get_property(dev, "reg", &len);
	if (reg == 0 || len < 5 * sizeof(unsigned int)) {
		/* doesn't look like a PCI device */
		*bus_ptr = 0xff;
		*devfn_ptr = 0xff;
		return -1;
	}
	*bus_ptr = reg[0] >> 16;
	*devfn_ptr = reg[0] >> 8;
	return 0;
}

/* This routines figures out on which root bridge a given PCI device
 * is attached.
 */
__pmac
int
pmac_pci_dev_root_bridge(unsigned char bus, unsigned char dev_fn)
{
	struct device_node *node, *bridge_node;
	int bridge = uninorth_default;

	if (uninorth_count == 0)
		return 0;
	if (bus == 0 && PCI_SLOT(dev_fn) < 11)
		return 0;
	
	/* We look for the OF device corresponding to this bus/devfn pair. If we
	 * don't find it, we default to the external PCI */
	bridge_node = NULL;
	node = find_pci_device_OFnode(bus, dev_fn & 0xf8);
	if (node) {
	    /* note: we don't stop on the first occurence since we need to go
             * up to the root bridge */
	    do {
		if (node->type && !strcmp(node->type, "pci") 
			&& device_is_compatible(node, "uni-north"))
			bridge_node = node;
		node=node->parent;
	    } while (node);
	}
	if (bridge_node) {
	    int i;
	    for (i=0;i<uninorth_count;i++)
		if (uninorth_bridges[i].node == bridge_node) {
		    bridge = i;
		    break;
		}
	}

	if (bridge == -1) {
		printk(KERN_WARNING "pmac_pci: no default bridge !\n");
		return 0;
	}

	return bridge;	
}

__pmac
void *
pmac_pci_dev_io_base(unsigned char bus, unsigned char devfn, int physical)
{
	int bridge = -1;
	if (uninorth_count != 0)
		bridge = pmac_pci_dev_root_bridge(bus, devfn);
	if (bridge == -1) {
		struct bridge_data *bp;

		if (bus > max_bus || (bp = bridges[bus]) == 0)
			return 0;
		return physical ? (void *) bp->io_base_phys : bp->io_base;
	}
	return physical ? (void *) uninorth_bridges[bridge].iobase_phys
		: uninorth_bridges[bridge].iobase;
}

__pmac
void *
pmac_pci_dev_mem_base(unsigned char bus, unsigned char devfn)
{
	return 0;
}

/* This function only works for bus 0, uni-N uses a different mecanism for
 * other busses (see below)
 */
#define UNI_N_CFA0(devfn, off)	\
	((1 << (unsigned long)PCI_SLOT(dev_fn)) \
	| (((unsigned long)PCI_FUNC(dev_fn)) << 8) \
	| (((unsigned long)(off)) & 0xFCUL))

/* This one is for type 1 config accesses */
#define UNI_N_CFA1(bus, devfn, off)	\
	((((unsigned long)(bus)) << 16) \
	|(((unsigned long)(devfn)) << 8) \
	|(((unsigned long)(off)) & 0xFCUL) \
	|1UL)
	
__pmac static
unsigned int
uni_north_access_data(unsigned char bus, unsigned char dev_fn,
				unsigned char offset)
{
	int bridge;
	unsigned int caddr;

	bridge = pmac_pci_dev_root_bridge(bus, dev_fn);
	if (bus == 0)
		caddr = UNI_N_CFA0(dev_fn, offset);
	else
		caddr = UNI_N_CFA1(bus, dev_fn, offset);
	
	if (bridge == -1) {
		printk(KERN_WARNING "pmac_pci: no default bridge !\n");
		return 0;
	}
		
	/* Uninorth will return garbage if we don't read back the value ! */
	out_le32(uninorth_bridges[bridge].cfg_addr, caddr);
	(void)in_le32(uninorth_bridges[bridge].cfg_addr);
	/* Yes, offset is & 7, not & 3 ! */
	return (unsigned int)(uninorth_bridges[bridge].cfg_data) + (offset & 0x07);
}

__pmac
int uni_pcibios_read_config_byte(unsigned char bus, unsigned char dev_fn,
				  unsigned char offset, unsigned char *val)
{
	unsigned int addr;
	
	*val = 0xff;
	addr = uni_north_access_data(bus, dev_fn, offset);
	if (!addr)
		return PCIBIOS_DEVICE_NOT_FOUND;
	*val = in_8((volatile unsigned char*)addr);
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int uni_pcibios_read_config_word(unsigned char bus, unsigned char dev_fn,
				  unsigned char offset, unsigned short *val)
{
	unsigned int addr;
	
	*val = 0xffff;
	addr = uni_north_access_data(bus, dev_fn, offset);
	if (!addr)
		return PCIBIOS_DEVICE_NOT_FOUND;
	*val = in_le16((volatile unsigned short*)addr);
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int uni_pcibios_read_config_dword(unsigned char bus, unsigned char dev_fn,
				   unsigned char offset, unsigned int *val)
{
	unsigned int addr;
	
	*val = 0xffff;
	addr = uni_north_access_data(bus, dev_fn, offset);
	if (!addr)
		return PCIBIOS_DEVICE_NOT_FOUND;
	*val = in_le32((volatile unsigned int*)addr);
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int uni_pcibios_write_config_byte(unsigned char bus, unsigned char dev_fn,
				   unsigned char offset, unsigned char val)
{
	unsigned int addr;
	
	addr = uni_north_access_data(bus, dev_fn, offset);
	if (!addr)
		return PCIBIOS_DEVICE_NOT_FOUND;
	out_8((volatile unsigned char *)addr, val);
	(void)in_8((volatile unsigned char *)addr);
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int uni_pcibios_write_config_word(unsigned char bus, unsigned char dev_fn,
				   unsigned char offset, unsigned short val)
{
	unsigned int addr;
	
	addr = uni_north_access_data(bus, dev_fn, offset);
	if (!addr)
		return PCIBIOS_DEVICE_NOT_FOUND;
	out_le16((volatile unsigned short *)addr, val);
	(void)in_le16((volatile unsigned short *)addr);
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int uni_pcibios_write_config_dword(unsigned char bus, unsigned char dev_fn,
				    unsigned char offset, unsigned int val)
{
	unsigned int addr;
	
	addr = uni_north_access_data(bus, dev_fn, offset);
	if (!addr)
		return PCIBIOS_DEVICE_NOT_FOUND;
	out_le32((volatile unsigned int *)addr, val);
	(void)in_le32((volatile unsigned int *)addr);
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int pmac_pcibios_read_config_byte(unsigned char bus, unsigned char dev_fn,
				  unsigned char offset, unsigned char *val)
{
	struct bridge_data *bp;

	*val = 0xff;
	if (bus > max_bus || (bp = bridges[bus]) == 0)
		return PCIBIOS_DEVICE_NOT_FOUND;
	if (bus == bp->bus_number) {
		if (dev_fn < (11 << 3))
			return PCIBIOS_DEVICE_NOT_FOUND;
		out_le32(bp->cfg_addr,
			 (1UL << (dev_fn >> 3)) + ((dev_fn & 7) << 8)
			 + (offset & ~3));
	} else {
		/* Bus number once again taken into consideration.
		 * Change applied from 2.1.24. This makes devices located
		 * behind PCI-PCI bridges visible.
		 * -Ranjit Deshpande, 01/20/99
		 */
		out_le32(bp->cfg_addr, (bus << 16) + (dev_fn << 8) + (offset & ~3) + 1);
	}
	udelay(2);
	*val = in_8(bp->cfg_data + (offset & 3));
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int pmac_pcibios_read_config_word(unsigned char bus, unsigned char dev_fn,
				  unsigned char offset, unsigned short *val)
{
	struct bridge_data *bp;

	*val = 0xffff;
	if (bus > max_bus || (bp = bridges[bus]) == 0)
		return PCIBIOS_DEVICE_NOT_FOUND;
	if ((offset & 1) != 0)
		return PCIBIOS_BAD_REGISTER_NUMBER;
	if (bus == bp->bus_number) {
		if (dev_fn < (11 << 3))
			return PCIBIOS_DEVICE_NOT_FOUND;
		out_le32(bp->cfg_addr,
			 (1UL << (dev_fn >> 3)) + ((dev_fn & 7) << 8)
			 + (offset & ~3));
	} else {
		/* See pci_read_config_byte */
		out_le32(bp->cfg_addr, (bus << 16) + (dev_fn << 8) + (offset & ~3) + 1);
	}
	udelay(2);
	*val = in_le16((volatile unsigned short *)(bp->cfg_data + (offset & 3)));
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int pmac_pcibios_read_config_dword(unsigned char bus, unsigned char dev_fn,
				   unsigned char offset, unsigned int *val)
{
	struct bridge_data *bp;

	*val = 0xffffffff;
	if (bus > max_bus || (bp = bridges[bus]) == 0)
		return PCIBIOS_DEVICE_NOT_FOUND;
	if ((offset & 3) != 0)
		return PCIBIOS_BAD_REGISTER_NUMBER;
	if (bus == bp->bus_number) {
		if (dev_fn < (11 << 3))
			return PCIBIOS_DEVICE_NOT_FOUND;
		out_le32(bp->cfg_addr,
			 (1UL << (dev_fn >> 3)) + ((dev_fn & 7) << 8)
			 + offset);
	} else {
		/* See pci_read_config_byte */
		out_le32(bp->cfg_addr, (bus << 16) + (dev_fn << 8) + offset + 1);
	}
	udelay(2);
	*val = in_le32((volatile unsigned int *)bp->cfg_data);
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int pmac_pcibios_write_config_byte(unsigned char bus, unsigned char dev_fn,
				   unsigned char offset, unsigned char val)
{
	struct bridge_data *bp;

	if (bus > max_bus || (bp = bridges[bus]) == 0)
		return PCIBIOS_DEVICE_NOT_FOUND;
	if (bus == bp->bus_number) {
		if (dev_fn < (11 << 3))
			return PCIBIOS_DEVICE_NOT_FOUND;
		out_le32(bp->cfg_addr,
			 (1UL << (dev_fn >> 3)) + ((dev_fn & 7) << 8)
			 + (offset & ~3));
	} else {
		/* See pci_read_config_byte */
		out_le32(bp->cfg_addr, (bus << 16) + (dev_fn << 8) + (offset & ~3) + 1);
	}
	udelay(2);
	out_8(bp->cfg_data + (offset & 3), val);
	return PCIBIOS_SUCCESSFUL;
}

__pmac
int pmac_pcibios_write_config_word(unsigned char bus, unsigned char dev_fn,
				   unsigned char offset, unsigned short val)
{
	struct bridge_data *bp;

	if (bus > max_bus || (bp = bridges[bus]) == 0)
		return PCIBIOS_DEVICE_NOT_FOUND;
	if ((offset & 1) != 0)
		return PCIBIOS_BAD_REGISTER_NUMBER;
	if (bus == bp->bus_number) {
		if (dev_fn < (11 << 3))
			return PCIBIOS_DEVICE_NOT_FOUND;
		out_le32(bp->cfg_addr,