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/*
* PCI autoconfiguration library
*
* Author: Matt Porter <mporter@mvista.com>
*
* Copyright 2000, 2001 MontaVista Software Inc.
*
* 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.
*/
/*
* Modified for MIPS by Jun Sun, jsun@mvista.com
*
* . Simplify the interface between pci_auto and the rest: a single function.
* . Assign resources from low address to upper address.
* . change most int to u32.
*
* Further modified to include it as mips generic code, ppopov@mvista.com.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <asm/pci_channel.h>
#define DEBUG
#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...)
#endif
/* These are used for config access before all the PCI probing has been done. */
int early_read_config_byte(struct pci_channel *hose, int bus, int dev_fn, int where, u8 *val);
int early_read_config_word(struct pci_channel *hose, int bus, int dev_fn, int where, u16 *val);
int early_read_config_dword(struct pci_channel *hose, int bus, int dev_fn, int where, u32 *val);
int early_write_config_byte(struct pci_channel *hose, int bus, int dev_fn, int where, u8 val);
int early_write_config_word(struct pci_channel *hose, int bus, int dev_fn, int where, u16 val);
int early_write_config_dword(struct pci_channel *hose, int bus, int dev_fn, int where, u32 val);
static u32 pciauto_lower_iospc;
static u32 pciauto_upper_iospc;
static u32 pciauto_lower_memspc;
static u32 pciauto_upper_memspc;
void __init
pciauto_setup_bars(struct pci_channel *hose,
int current_bus,
int pci_devfn)
{
u32 bar_response, bar_size, bar_value;
u32 bar, addr_mask, bar_nr = 0;
u32 * upper_limit;
u32 * lower_limit;
int found_mem64 = 0;
DBG("PCI Autoconfig: Found Bus %d, Device %d, Function %d\n",
current_bus, PCI_SLOT(pci_devfn), PCI_FUNC(pci_devfn) );
for (bar = PCI_BASE_ADDRESS_0; bar <= PCI_BASE_ADDRESS_5; bar+=4) {
/* Tickle the BAR and get the response */
early_write_config_dword(hose,
current_bus,
pci_devfn,
bar,
0xffffffff);
early_read_config_dword(hose,
current_bus,
pci_devfn,
bar,
&bar_response);
/* If BAR is not implemented go to the next BAR */
if (!bar_response)
continue;
/* Check the BAR type and set our address mask */
if (bar_response & PCI_BASE_ADDRESS_SPACE) {
addr_mask = PCI_BASE_ADDRESS_IO_MASK;
upper_limit = &pciauto_upper_iospc;
lower_limit = &pciauto_lower_iospc;
DBG("PCI Autoconfig: BAR %d, I/O, ", bar_nr);
} else {
if ((bar_response & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
PCI_BASE_ADDRESS_MEM_TYPE_64)
found_mem64 = 1;
addr_mask = PCI_BASE_ADDRESS_MEM_MASK;
upper_limit = &pciauto_upper_memspc;
lower_limit = &pciauto_lower_memspc;
DBG("PCI Autoconfig: BAR %d, Mem, ", bar_nr);
}
/* Calculate requested size */
bar_size = ~(bar_response & addr_mask) + 1;
/* Allocate a base address */
bar_value = ((*lower_limit - 1) & ~(bar_size - 1)) + bar_size;
/* Write it out and update our limit */
early_write_config_dword(hose, current_bus, pci_devfn,
bar, bar_value);
*lower_limit = bar_value + bar_size;
/*
* If we are a 64-bit decoder then increment to the
* upper 32 bits of the bar and force it to locate
* in the lower 4GB of memory.
*/
if (found_mem64) {
bar += 4;
early_write_config_dword(hose,
current_bus,
pci_devfn,
bar,
0x00000000);
}
bar_nr++;
DBG("size=0x%x, address=0x%x\n",
bar_size, bar_value);
}
}
void __init
pciauto_prescan_setup_bridge(struct pci_channel *hose,
int current_bus,
int pci_devfn,
int sub_bus)
{
int cmdstat;
/* Configure bus number registers */
early_write_config_byte(hose, current_bus, pci_devfn,
PCI_PRIMARY_BUS, current_bus);
early_write_config_byte(hose, current_bus, pci_devfn,
PCI_SECONDARY_BUS, sub_bus + 1);
early_write_config_byte(hose, current_bus, pci_devfn,
PCI_SUBORDINATE_BUS, 0xff);
/* Round memory allocator to 1MB boundary */
pciauto_upper_memspc &= ~(0x100000 - 1);
/* Round I/O allocator to 4KB boundary */
pciauto_upper_iospc &= ~(0x1000 - 1);
/* Set up memory and I/O filter limits, assume 32-bit I/O space */
early_write_config_word(hose, current_bus, pci_devfn, PCI_MEMORY_LIMIT,
((pciauto_upper_memspc - 1) & 0xfff00000) >> 16);
early_write_config_byte(hose, current_bus, pci_devfn, PCI_IO_LIMIT,
((pciauto_upper_iospc - 1) & 0x0000f000) >> 8);
early_write_config_word(hose, current_bus, pci_devfn,
PCI_IO_LIMIT_UPPER16,
((pciauto_upper_iospc - 1) & 0xffff0000) >> 16);
/* We don't support prefetchable memory for now, so disable */
early_write_config_word(hose, current_bus, pci_devfn,
PCI_PREF_MEMORY_BASE, 0x1000);
early_write_config_word(hose, current_bus, pci_devfn,
PCI_PREF_MEMORY_LIMIT, 0x1000);
/* Enable memory and I/O accesses, enable bus master */
early_read_config_dword(hose, current_bus, pci_devfn, PCI_COMMAND,
&cmdstat);
early_write_config_dword(hose, current_bus, pci_devfn, PCI_COMMAND,
cmdstat | PCI_COMMAND_IO | PCI_COMMAND_MEMORY |
PCI_COMMAND_MASTER);
}
void __init
pciauto_postscan_setup_bridge(struct pci_channel *hose,
int current_bus,
int pci_devfn,
int sub_bus)
{
/* Configure bus number registers */
early_write_config_byte(hose, current_bus, pci_devfn,
PCI_SUBORDINATE_BUS, sub_bus);
/* Round memory allocator to 1MB boundary */
pciauto_upper_memspc &= ~(0x100000 - 1);
early_write_config_word(hose, current_bus, pci_devfn, PCI_MEMORY_BASE,
pciauto_upper_memspc >> 16);
/* Round I/O allocator to 4KB boundary */
pciauto_upper_iospc &= ~(0x1000 - 1);
early_write_config_byte(hose, current_bus, pci_devfn, PCI_IO_BASE,
(pciauto_upper_iospc & 0x0000f000) >> 8);
early_write_config_word(hose, current_bus, pci_devfn,
PCI_IO_BASE_UPPER16, pciauto_upper_iospc >> 16);
}
#define PCIAUTO_IDE_MODE_MASK 0x05
int __init
pciauto_bus_scan(struct pci_channel *hose, int current_bus)
{
int sub_bus;
u32 pci_devfn, pci_class, cmdstat, found_multi=0;
unsigned short vid;
unsigned char header_type;
int devfn_start = 0;
int devfn_stop = 0xff;
sub_bus = current_bus;
if (hose->first_devfn)
devfn_start = hose->first_devfn;
if (hose->last_devfn)
devfn_stop = hose->last_devfn;
for (pci_devfn=devfn_start; pci_devfn<devfn_stop; pci_devfn++) {
if (PCI_FUNC(pci_devfn) && !found_multi)
continue;
early_read_config_byte(hose, current_bus, pci_devfn,
PCI_HEADER_TYPE, &header_type);
if (!PCI_FUNC(pci_devfn))
found_multi = header_type & 0x80;
early_read_config_word(hose, current_bus, pci_devfn,
PCI_VENDOR_ID, &vid);
if (vid == 0xffff) continue;
early_read_config_dword(hose, current_bus, pci_devfn,
PCI_CLASS_REVISION, &pci_class);
if ((pci_class >> 16) == PCI_CLASS_BRIDGE_PCI) {
DBG("PCI Autoconfig: Found P2P bridge, device %d\n", PCI_SLOT(pci_devfn));
pciauto_prescan_setup_bridge(hose, current_bus,
pci_devfn, sub_bus);
sub_bus = pciauto_bus_scan(hose, sub_bus+1);
pciauto_postscan_setup_bridge(hose, current_bus,
pci_devfn, sub_bus);
} else if ((pci_class >> 16) == PCI_CLASS_STORAGE_IDE) {
unsigned char prg_iface;
early_read_config_byte(hose, current_bus, pci_devfn,
PCI_CLASS_PROG, &prg_iface);
if (!(prg_iface & PCIAUTO_IDE_MODE_MASK)) {
DBG("PCI Autoconfig: Skipping legacy mode IDE controller\n");
continue;
}
}
/*
* Found a peripheral, enable some standard
* settings
*/
early_read_config_dword(hose, current_bus, pci_devfn,
PCI_COMMAND, &cmdstat);
early_write_config_dword(hose, current_bus, pci_devfn,
PCI_COMMAND, cmdstat | PCI_COMMAND_IO |
PCI_COMMAND_MEMORY |
PCI_COMMAND_MASTER);
early_write_config_byte(hose, current_bus, pci_devfn,
PCI_LATENCY_TIMER, 0x80);
/* Allocate PCI I/O and/or memory space */
pciauto_setup_bars(hose, current_bus, pci_devfn);
}
return sub_bus;
}
int __init
pciauto_assign_resources(int busno, struct pci_channel *hose)
{
/* setup resource limits */
pciauto_lower_iospc = hose->io_resource->start;
pciauto_upper_iospc = hose->io_resource->end + 1;
pciauto_lower_memspc = hose->mem_resource->start;
pciauto_upper_memspc = hose->mem_resource->end + 1;
return pciauto_bus_scan(hose, busno);
}
/*
* These functions are used early on before PCI scanning is done
* and all of the pci_dev and pci_bus structures have been created.
*/
static struct pci_dev *fake_pci_dev(struct pci_channel *hose, int busnr,
int devfn)
{
static struct pci_dev dev;
static struct pci_bus bus;
dev.bus = &bus;
dev.sysdata = hose;
dev.devfn = devfn;
bus.number = busnr;
bus.ops = hose->pci_ops;
return &dev;
}
#define EARLY_PCI_OP(rw, size, type) \
int early_##rw##_config_##size(struct pci_channel *hose, int bus, \
int devfn, int offset, type value) \
{ \
return pci_##rw##_config_##size(fake_pci_dev(hose, bus, devfn), \
offset, value); \
}
EARLY_PCI_OP(read, byte, u8 *)
EARLY_PCI_OP(read, word, u16 *)
EARLY_PCI_OP(read, dword, u32 *)
EARLY_PCI_OP(write, byte, u8)
EARLY_PCI_OP(write, word, u16)
EARLY_PCI_OP(write, dword, u32)
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