linux/arch/mips/pci/pci.c

304 lines
7.4 KiB
C

/*
* 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.
*
* Copyright (C) 2003, 04, 11 Ralf Baechle (ralf@linux-mips.org)
* Copyright (C) 2011 Wind River Systems,
* written by Ralf Baechle (ralf@linux-mips.org)
*/
#include <linux/bug.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <asm/cpu-info.h>
/*
* If PCI_PROBE_ONLY in pci_flags is set, we don't change any PCI resource
* assignments.
*/
/*
* The PCI controller list.
*/
static struct pci_controller *hose_head, **hose_tail = &hose_head;
unsigned long PCIBIOS_MIN_IO;
unsigned long PCIBIOS_MIN_MEM;
static int pci_initialized;
/*
* We need to avoid collisions with `mirrored' VGA ports
* and other strange ISA hardware, so we always want the
* addresses to be allocated in the 0x000-0x0ff region
* modulo 0x400.
*
* Why? Because some silly external IO cards only decode
* the low 10 bits of the IO address. The 0x00-0xff region
* is reserved for motherboard devices that decode all 16
* bits, so it's ok to allocate at, say, 0x2800-0x28ff,
* but we want to try to avoid allocating at 0x2900-0x2bff
* which might have be mirrored at 0x0100-0x03ff..
*/
resource_size_t
pcibios_align_resource(void *data, const struct resource *res,
resource_size_t size, resource_size_t align)
{
struct pci_dev *dev = data;
struct pci_controller *hose = dev->sysdata;
resource_size_t start = res->start;
if (res->flags & IORESOURCE_IO) {
/* Make sure we start at our min on all hoses */
if (start < PCIBIOS_MIN_IO + hose->io_resource->start)
start = PCIBIOS_MIN_IO + hose->io_resource->start;
/*
* Put everything into 0x00-0xff region modulo 0x400
*/
if (start & 0x300)
start = (start + 0x3ff) & ~0x3ff;
} else if (res->flags & IORESOURCE_MEM) {
/* Make sure we start at our min on all hoses */
if (start < PCIBIOS_MIN_MEM + hose->mem_resource->start)
start = PCIBIOS_MIN_MEM + hose->mem_resource->start;
}
return start;
}
static void __devinit pcibios_scanbus(struct pci_controller *hose)
{
static int next_busno;
static int need_domain_info;
LIST_HEAD(resources);
struct pci_bus *bus;
if (!hose->iommu)
PCI_DMA_BUS_IS_PHYS = 1;
if (hose->get_busno && pci_has_flag(PCI_PROBE_ONLY))
next_busno = (*hose->get_busno)();
pci_add_resource_offset(&resources,
hose->mem_resource, hose->mem_offset);
pci_add_resource_offset(&resources, hose->io_resource, hose->io_offset);
bus = pci_scan_root_bus(NULL, next_busno, hose->pci_ops, hose,
&resources);
if (!bus)
pci_free_resource_list(&resources);
hose->bus = bus;
need_domain_info = need_domain_info || hose->index;
hose->need_domain_info = need_domain_info;
if (bus) {
next_busno = bus->subordinate + 1;
/* Don't allow 8-bit bus number overflow inside the hose -
reserve some space for bridges. */
if (next_busno > 224) {
next_busno = 0;
need_domain_info = 1;
}
if (!pci_has_flag(PCI_PROBE_ONLY)) {
pci_bus_size_bridges(bus);
pci_bus_assign_resources(bus);
pci_enable_bridges(bus);
}
}
}
static DEFINE_MUTEX(pci_scan_mutex);
void __devinit register_pci_controller(struct pci_controller *hose)
{
if (request_resource(&iomem_resource, hose->mem_resource) < 0)
goto out;
if (request_resource(&ioport_resource, hose->io_resource) < 0) {
release_resource(hose->mem_resource);
goto out;
}
*hose_tail = hose;
hose_tail = &hose->next;
/*
* Do not panic here but later - this might happen before console init.
*/
if (!hose->io_map_base) {
printk(KERN_WARNING
"registering PCI controller with io_map_base unset\n");
}
/*
* Scan the bus if it is register after the PCI subsystem
* initialization.
*/
if (pci_initialized) {
mutex_lock(&pci_scan_mutex);
pcibios_scanbus(hose);
mutex_unlock(&pci_scan_mutex);
}
return;
out:
printk(KERN_WARNING
"Skipping PCI bus scan due to resource conflict\n");
}
static void __init pcibios_set_cache_line_size(void)
{
struct cpuinfo_mips *c = &current_cpu_data;
unsigned int lsize;
/*
* Set PCI cacheline size to that of the highest level in the
* cache hierarchy.
*/
lsize = c->dcache.linesz;
lsize = c->scache.linesz ? : lsize;
lsize = c->tcache.linesz ? : lsize;
BUG_ON(!lsize);
pci_dfl_cache_line_size = lsize >> 2;
pr_debug("PCI: pci_cache_line_size set to %d bytes\n", lsize);
}
static int __init pcibios_init(void)
{
struct pci_controller *hose;
pcibios_set_cache_line_size();
/* Scan all of the recorded PCI controllers. */
for (hose = hose_head; hose; hose = hose->next)
pcibios_scanbus(hose);
pci_fixup_irqs(pci_common_swizzle, pcibios_map_irq);
pci_initialized = 1;
return 0;
}
subsys_initcall(pcibios_init);
static int pcibios_enable_resources(struct pci_dev *dev, int mask)
{
u16 cmd, old_cmd;
int idx;
struct resource *r;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
old_cmd = cmd;
for (idx=0; idx < PCI_NUM_RESOURCES; idx++) {
/* Only set up the requested stuff */
if (!(mask & (1<<idx)))
continue;
r = &dev->resource[idx];
if (!(r->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
continue;
if ((idx == PCI_ROM_RESOURCE) &&
(!(r->flags & IORESOURCE_ROM_ENABLE)))
continue;
if (!r->start && r->end) {
printk(KERN_ERR "PCI: Device %s not available "
"because of resource collisions\n",
pci_name(dev));
return -EINVAL;
}
if (r->flags & IORESOURCE_IO)
cmd |= PCI_COMMAND_IO;
if (r->flags & IORESOURCE_MEM)
cmd |= PCI_COMMAND_MEMORY;
}
if (cmd != old_cmd) {
printk("PCI: Enabling device %s (%04x -> %04x)\n",
pci_name(dev), old_cmd, cmd);
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
return 0;
}
unsigned int pcibios_assign_all_busses(void)
{
return 1;
}
int pcibios_enable_device(struct pci_dev *dev, int mask)
{
int err;
if ((err = pcibios_enable_resources(dev, mask)) < 0)
return err;
return pcibios_plat_dev_init(dev);
}
void __devinit pcibios_fixup_bus(struct pci_bus *bus)
{
struct pci_dev *dev = bus->self;
if (pci_has_flag(PCI_PROBE_ONLY) && dev &&
(dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
pci_read_bridge_bases(bus);
}
}
void __init
pcibios_update_irq(struct pci_dev *dev, int irq)
{
pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
}
#ifdef CONFIG_HOTPLUG
EXPORT_SYMBOL(PCIBIOS_MIN_IO);
EXPORT_SYMBOL(PCIBIOS_MIN_MEM);
#endif
int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
enum pci_mmap_state mmap_state, int write_combine)
{
unsigned long prot;
/*
* I/O space can be accessed via normal processor loads and stores on
* this platform but for now we elect not to do this and portable
* drivers should not do this anyway.
*/
if (mmap_state == pci_mmap_io)
return -EINVAL;
/*
* Ignore write-combine; for now only return uncached mappings.
*/
prot = pgprot_val(vma->vm_page_prot);
prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
vma->vm_page_prot = __pgprot(prot);
return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
vma->vm_end - vma->vm_start, vma->vm_page_prot);
}
char * (*pcibios_plat_setup)(char *str) __devinitdata;
char *__devinit pcibios_setup(char *str)
{
if (pcibios_plat_setup)
return pcibios_plat_setup(str);
return str;
}