linux/arch/ppc/syslib/pci_auto.c

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/*
* arch/ppc/syslib/pci_auto.c
*
* PCI autoconfiguration library
*
* Author: Matt Porter <mporter@mvista.com>
*
* 2001 (c) MontaVista, Software, Inc. This file is licensed under
* the terms of the GNU General Public License version 2. This program
* is licensed "as is" without any warranty of any kind, whether express
* or implied.
*/
/*
* The CardBus support is very preliminary. Preallocating space is
* the way to go but will require some change in card services to
* make it useful. Eventually this will ensure that we can put
* multiple CB bridges behind multiple P2P bridges. For now, at
* least it ensures that we place the CB bridge BAR and assigned
* initial bus numbers. I definitely need to do something about
* the lack of 16-bit I/O support. -MDP
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <asm/pci-bridge.h>
#define PCIAUTO_IDE_MODE_MASK 0x05
#undef DEBUG
#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...)
#endif /* DEBUG */
static int pciauto_upper_iospc;
static int pciauto_upper_memspc;
void __init pciauto_setup_bars(struct pci_controller *hose,
int current_bus,
int pci_devfn,
int bar_limit)
{
int bar_response, bar_size, bar_value;
int bar, addr_mask;
int * upper_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 <= bar_limit; 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;
DBG("PCI Autoconfig: BAR 0x%x, I/O, ", bar);
} 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;
DBG("PCI Autoconfig: BAR 0x%x, Mem ", bar);
}
/* Calculate requested size */
bar_size = ~(bar_response & addr_mask) + 1;
/* Allocate a base address */
bar_value = (*upper_limit - bar_size) & ~(bar_size - 1);
/* Write it out and update our limit */
early_write_config_dword(hose,
current_bus,
pci_devfn,
bar,
bar_value);
*upper_limit = bar_value;
/*
* 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);
found_mem64 = 0;
}
DBG("size=0x%x, address=0x%x\n",
bar_size, bar_value);
}
}
void __init pciauto_prescan_setup_bridge(struct pci_controller *hose,
int current_bus,
int pci_devfn,
int sub_bus,
int *iosave,
int *memsave)
{
/* 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);
*memsave = pciauto_upper_memspc;
/* Round I/O allocator to 4KB boundary */
pciauto_upper_iospc &= ~(0x1000 - 1);
*iosave = pciauto_upper_iospc;
/* 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);
/* Zero upper 32 bits of prefetchable base/limit */
early_write_config_dword(hose,
current_bus,
pci_devfn,
PCI_PREF_BASE_UPPER32,
0);
early_write_config_dword(hose,
current_bus,
pci_devfn,
PCI_PREF_LIMIT_UPPER32,
0);
}
void __init pciauto_postscan_setup_bridge(struct pci_controller *hose,
int current_bus,
int pci_devfn,
int sub_bus,
int *iosave,
int *memsave)
{
int cmdstat;
/* Configure bus number registers */
early_write_config_byte(hose,
current_bus,
pci_devfn,
PCI_SUBORDINATE_BUS,
sub_bus);
/*
* Round memory allocator to 1MB boundary.
* If no space used, allocate minimum.
*/
pciauto_upper_memspc &= ~(0x100000 - 1);
if (*memsave == pciauto_upper_memspc)
pciauto_upper_memspc -= 0x00100000;
early_write_config_word(hose,
current_bus,
pci_devfn,
PCI_MEMORY_BASE,
pciauto_upper_memspc >> 16);
/* Allocate 1MB for pre-fretch */
early_write_config_word(hose,
current_bus,
pci_devfn,
PCI_PREF_MEMORY_LIMIT,
((pciauto_upper_memspc - 1) & 0xfff00000) >> 16);
pciauto_upper_memspc -= 0x100000;
early_write_config_word(hose,
current_bus,
pci_devfn,
PCI_PREF_MEMORY_BASE,
pciauto_upper_memspc >> 16);
/* Round I/O allocator to 4KB boundary */
pciauto_upper_iospc &= ~(0x1000 - 1);
if (*iosave == pciauto_upper_iospc)
pciauto_upper_iospc -= 0x1000;
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);
/* 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_prescan_setup_cardbus_bridge(struct pci_controller *hose,
int current_bus,
int pci_devfn,
int sub_bus,
int *iosave,
int *memsave)
{
/* 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 4KB boundary */
pciauto_upper_memspc &= ~(0x1000 - 1);
*memsave = pciauto_upper_memspc;
/* Round I/O allocator to 4 byte boundary */
pciauto_upper_iospc &= ~(0x4 - 1);
*iosave = pciauto_upper_iospc;
/* Set up memory and I/O filter limits, assume 32-bit I/O space */
early_write_config_dword(hose,
current_bus,
pci_devfn,
0x20,
pciauto_upper_memspc - 1);
early_write_config_dword(hose,
current_bus,
pci_devfn,
0x30,
pciauto_upper_iospc - 1);
}
void __init pciauto_postscan_setup_cardbus_bridge(struct pci_controller *hose,
int current_bus,
int pci_devfn,
int sub_bus,
int *iosave,
int *memsave)
{
int cmdstat;
/*
* Configure subordinate bus number. The PCI subsystem
* bus scan will renumber buses (reserving three additional
* for this PCI<->CardBus bridge for the case where a CardBus
* adapter contains a P2P or CB2CB bridge.
*/
early_write_config_byte(hose,
current_bus,
pci_devfn,
PCI_SUBORDINATE_BUS,
sub_bus);
/*
* Reserve an additional 4MB for mem space and 16KB for
* I/O space. This should cover any additional space
* requirement of unusual CardBus devices with
* additional bridges that can consume more address space.
*
* Although pcmcia-cs currently will reprogram bridge
* windows, the goal is to add an option to leave them
* alone and use the bridge window ranges as the regions
* that are searched for free resources upon hot-insertion
* of a device. This will allow a PCI<->CardBus bridge
* configured by this routine to happily live behind a
* P2P bridge in a system.
*/
pciauto_upper_memspc -= 0x00400000;
pciauto_upper_iospc -= 0x00004000;
/* Round memory allocator to 4KB boundary */
pciauto_upper_memspc &= ~(0x1000 - 1);
early_write_config_dword(hose,
current_bus,
pci_devfn,
0x1c,
pciauto_upper_memspc);
/* Round I/O allocator to 4 byte boundary */
pciauto_upper_iospc &= ~(0x4 - 1);
early_write_config_dword(hose,
current_bus,
pci_devfn,
0x2c,
pciauto_upper_iospc);
/* 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);
}
int __init pciauto_bus_scan(struct pci_controller *hose, int current_bus)
{
int sub_bus, pci_devfn, pci_class, cmdstat, found_multi = 0;
unsigned short vid;
unsigned char header_type;
/*
* Fetch our I/O and memory space upper boundaries used
* to allocated base addresses on this hose.
*/
if (current_bus == hose->first_busno) {
pciauto_upper_iospc = hose->io_space.end + 1;
pciauto_upper_memspc = hose->mem_space.end + 1;
}
sub_bus = current_bus;
for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++) {
/* Skip our host bridge */
if ( (current_bus == hose->first_busno) && (pci_devfn == 0) )
continue;
if (PCI_FUNC(pci_devfn) && !found_multi)
continue;
/* If config space read fails from this device, move on */
if (early_read_config_byte(hose,
current_bus,
pci_devfn,
PCI_HEADER_TYPE,
&header_type))
continue;
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) {
early_read_config_dword(hose,
current_bus,
pci_devfn,
PCI_CLASS_REVISION, &pci_class);
if ( (pci_class >> 16) == PCI_CLASS_BRIDGE_PCI ) {
int iosave, memsave;
DBG("PCI Autoconfig: Found P2P bridge, device %d\n", PCI_SLOT(pci_devfn));
/* Allocate PCI I/O and/or memory space */
pciauto_setup_bars(hose,
current_bus,
pci_devfn,
PCI_BASE_ADDRESS_1);
pciauto_prescan_setup_bridge(hose,
current_bus,
pci_devfn,
sub_bus,
&iosave,
&memsave);
sub_bus = pciauto_bus_scan(hose, sub_bus+1);
pciauto_postscan_setup_bridge(hose,
current_bus,
pci_devfn,
sub_bus,
&iosave,
&memsave);
} else if ((pci_class >> 16) == PCI_CLASS_BRIDGE_CARDBUS) {
int iosave, memsave;
DBG("PCI Autoconfig: Found CardBus bridge, device %d function %d\n", PCI_SLOT(pci_devfn), PCI_FUNC(pci_devfn));
/* Place CardBus Socket/ExCA registers */
pciauto_setup_bars(hose,
current_bus,
pci_devfn,
PCI_BASE_ADDRESS_0);
pciauto_prescan_setup_cardbus_bridge(hose,
current_bus,
pci_devfn,
sub_bus,
&iosave,
&memsave);
sub_bus = pciauto_bus_scan(hose, sub_bus+1);
pciauto_postscan_setup_cardbus_bridge(hose,
current_bus,
pci_devfn,
sub_bus,
&iosave,
&memsave);
} 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;
}
}
/* Allocate PCI I/O and/or memory space */
pciauto_setup_bars(hose,
current_bus,
pci_devfn,
PCI_BASE_ADDRESS_5);
/*
* 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);
}
}
}
return sub_bus;
}