We currently enable PCI bridges after scanning a bus and assigning resources. This is often done in arch code. This patch changes this so we don't enable a bridge until necessary, i.e., until we enable a PCI device behind the bridge. We do this in the generic pci_enable_device() path, so this also removes the arch-specific code to enable bridges. [bhelgaas: changelog] Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
		
			
				
	
	
		
			322 lines
		
	
	
	
		
			7.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			322 lines
		
	
	
	
		
			7.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * New-style PCI core.
 | 
						|
 *
 | 
						|
 * Copyright (c) 2004 - 2009  Paul Mundt
 | 
						|
 * Copyright (c) 2002  M. R. Brown
 | 
						|
 *
 | 
						|
 * Modelled after arch/mips/pci/pci.c:
 | 
						|
 *  Copyright (C) 2003, 04 Ralf Baechle (ralf@linux-mips.org)
 | 
						|
 *
 | 
						|
 * This file is subject to the terms and conditions of the GNU General Public
 | 
						|
 * License.  See the file "COPYING" in the main directory of this archive
 | 
						|
 * for more details.
 | 
						|
 */
 | 
						|
#include <linux/kernel.h>
 | 
						|
#include <linux/mm.h>
 | 
						|
#include <linux/pci.h>
 | 
						|
#include <linux/init.h>
 | 
						|
#include <linux/types.h>
 | 
						|
#include <linux/dma-debug.h>
 | 
						|
#include <linux/io.h>
 | 
						|
#include <linux/mutex.h>
 | 
						|
#include <linux/spinlock.h>
 | 
						|
#include <linux/export.h>
 | 
						|
 | 
						|
unsigned long PCIBIOS_MIN_IO = 0x0000;
 | 
						|
unsigned long PCIBIOS_MIN_MEM = 0;
 | 
						|
 | 
						|
/*
 | 
						|
 * The PCI controller list.
 | 
						|
 */
 | 
						|
static struct pci_channel *hose_head, **hose_tail = &hose_head;
 | 
						|
 | 
						|
static int pci_initialized;
 | 
						|
 | 
						|
static void pcibios_scanbus(struct pci_channel *hose)
 | 
						|
{
 | 
						|
	static int next_busno;
 | 
						|
	static int need_domain_info;
 | 
						|
	LIST_HEAD(resources);
 | 
						|
	struct resource *res;
 | 
						|
	resource_size_t offset;
 | 
						|
	int i;
 | 
						|
	struct pci_bus *bus;
 | 
						|
 | 
						|
	for (i = 0; i < hose->nr_resources; i++) {
 | 
						|
		res = hose->resources + i;
 | 
						|
		offset = 0;
 | 
						|
		if (res->flags & IORESOURCE_IO)
 | 
						|
			offset = hose->io_offset;
 | 
						|
		else if (res->flags & IORESOURCE_MEM)
 | 
						|
			offset = hose->mem_offset;
 | 
						|
		pci_add_resource_offset(&resources, res, offset);
 | 
						|
	}
 | 
						|
 | 
						|
	bus = pci_scan_root_bus(NULL, next_busno, hose->pci_ops, hose,
 | 
						|
				&resources);
 | 
						|
	hose->bus = bus;
 | 
						|
 | 
						|
	need_domain_info = need_domain_info || hose->index;
 | 
						|
	hose->need_domain_info = need_domain_info;
 | 
						|
	if (bus) {
 | 
						|
		next_busno = bus->busn_res.end + 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;
 | 
						|
		}
 | 
						|
 | 
						|
		pci_bus_size_bridges(bus);
 | 
						|
		pci_bus_assign_resources(bus);
 | 
						|
	} else {
 | 
						|
		pci_free_resource_list(&resources);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * This interrupt-safe spinlock protects all accesses to PCI
 | 
						|
 * configuration space.
 | 
						|
 */
 | 
						|
DEFINE_RAW_SPINLOCK(pci_config_lock);
 | 
						|
static DEFINE_MUTEX(pci_scan_mutex);
 | 
						|
 | 
						|
int register_pci_controller(struct pci_channel *hose)
 | 
						|
{
 | 
						|
	int i;
 | 
						|
 | 
						|
	for (i = 0; i < hose->nr_resources; i++) {
 | 
						|
		struct resource *res = hose->resources + i;
 | 
						|
 | 
						|
		if (res->flags & IORESOURCE_IO) {
 | 
						|
			if (request_resource(&ioport_resource, res) < 0)
 | 
						|
				goto out;
 | 
						|
		} else {
 | 
						|
			if (request_resource(&iomem_resource, res) < 0)
 | 
						|
				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");
 | 
						|
	}
 | 
						|
 | 
						|
	/*
 | 
						|
	 * Setup the ERR/PERR and SERR timers, if available.
 | 
						|
	 */
 | 
						|
	pcibios_enable_timers(hose);
 | 
						|
 | 
						|
	/*
 | 
						|
	 * 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 0;
 | 
						|
 | 
						|
out:
 | 
						|
	for (--i; i >= 0; i--)
 | 
						|
		release_resource(&hose->resources[i]);
 | 
						|
 | 
						|
	printk(KERN_WARNING "Skipping PCI bus scan due to resource conflict\n");
 | 
						|
	return -1;
 | 
						|
}
 | 
						|
 | 
						|
static int __init pcibios_init(void)
 | 
						|
{
 | 
						|
	struct pci_channel *hose;
 | 
						|
 | 
						|
	/* 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_platform_irq);
 | 
						|
 | 
						|
	dma_debug_add_bus(&pci_bus_type);
 | 
						|
 | 
						|
	pci_initialized = 1;
 | 
						|
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
subsys_initcall(pcibios_init);
 | 
						|
 | 
						|
/*
 | 
						|
 *  Called after each bus is probed, but before its children
 | 
						|
 *  are examined.
 | 
						|
 */
 | 
						|
void pcibios_fixup_bus(struct pci_bus *bus)
 | 
						|
{
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * 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.
 | 
						|
 */
 | 
						|
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_channel *hose = dev->sysdata;
 | 
						|
	resource_size_t start = res->start;
 | 
						|
 | 
						|
	if (res->flags & IORESOURCE_IO) {
 | 
						|
		if (start < PCIBIOS_MIN_IO + hose->resources[0].start)
 | 
						|
			start = PCIBIOS_MIN_IO + hose->resources[0].start;
 | 
						|
 | 
						|
		/*
 | 
						|
                 * Put everything into 0x00-0xff region modulo 0x400.
 | 
						|
		 */
 | 
						|
		if (start & 0x300)
 | 
						|
			start = (start + 0x3ff) & ~0x3ff;
 | 
						|
	}
 | 
						|
 | 
						|
	return start;
 | 
						|
}
 | 
						|
 | 
						|
int pcibios_enable_device(struct pci_dev *dev, int mask)
 | 
						|
{
 | 
						|
	return pci_enable_resources(dev, mask);
 | 
						|
}
 | 
						|
 | 
						|
static void __init
 | 
						|
pcibios_bus_report_status_early(struct pci_channel *hose,
 | 
						|
				int top_bus, int current_bus,
 | 
						|
				unsigned int status_mask, int warn)
 | 
						|
{
 | 
						|
	unsigned int pci_devfn;
 | 
						|
	u16 status;
 | 
						|
	int ret;
 | 
						|
 | 
						|
	for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++) {
 | 
						|
		if (PCI_FUNC(pci_devfn))
 | 
						|
			continue;
 | 
						|
		ret = early_read_config_word(hose, top_bus, current_bus,
 | 
						|
					     pci_devfn, PCI_STATUS, &status);
 | 
						|
		if (ret != PCIBIOS_SUCCESSFUL)
 | 
						|
			continue;
 | 
						|
		if (status == 0xffff)
 | 
						|
			continue;
 | 
						|
 | 
						|
		early_write_config_word(hose, top_bus, current_bus,
 | 
						|
					pci_devfn, PCI_STATUS,
 | 
						|
					status & status_mask);
 | 
						|
		if (warn)
 | 
						|
			printk("(%02x:%02x: %04X) ", current_bus,
 | 
						|
			       pci_devfn, status);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * We can't use pci_find_device() here since we are
 | 
						|
 * called from interrupt context.
 | 
						|
 */
 | 
						|
static void __init_refok
 | 
						|
pcibios_bus_report_status(struct pci_bus *bus, unsigned int status_mask,
 | 
						|
			  int warn)
 | 
						|
{
 | 
						|
	struct pci_dev *dev;
 | 
						|
 | 
						|
	list_for_each_entry(dev, &bus->devices, bus_list) {
 | 
						|
		u16 status;
 | 
						|
 | 
						|
		/*
 | 
						|
		 * ignore host bridge - we handle
 | 
						|
		 * that separately
 | 
						|
		 */
 | 
						|
		if (dev->bus->number == 0 && dev->devfn == 0)
 | 
						|
			continue;
 | 
						|
 | 
						|
		pci_read_config_word(dev, PCI_STATUS, &status);
 | 
						|
		if (status == 0xffff)
 | 
						|
			continue;
 | 
						|
 | 
						|
		if ((status & status_mask) == 0)
 | 
						|
			continue;
 | 
						|
 | 
						|
		/* clear the status errors */
 | 
						|
		pci_write_config_word(dev, PCI_STATUS, status & status_mask);
 | 
						|
 | 
						|
		if (warn)
 | 
						|
			printk("(%s: %04X) ", pci_name(dev), status);
 | 
						|
	}
 | 
						|
 | 
						|
	list_for_each_entry(dev, &bus->devices, bus_list)
 | 
						|
		if (dev->subordinate)
 | 
						|
			pcibios_bus_report_status(dev->subordinate, status_mask, warn);
 | 
						|
}
 | 
						|
 | 
						|
void __init_refok pcibios_report_status(unsigned int status_mask, int warn)
 | 
						|
{
 | 
						|
	struct pci_channel *hose;
 | 
						|
 | 
						|
	for (hose = hose_head; hose; hose = hose->next) {
 | 
						|
		if (unlikely(!hose->bus))
 | 
						|
			pcibios_bus_report_status_early(hose, hose_head->index,
 | 
						|
					hose->index, status_mask, warn);
 | 
						|
		else
 | 
						|
			pcibios_bus_report_status(hose->bus, status_mask, warn);
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
 | 
						|
			enum pci_mmap_state mmap_state, int write_combine)
 | 
						|
{
 | 
						|
	/*
 | 
						|
	 * 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.
 | 
						|
	 */
 | 
						|
	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 | 
						|
 | 
						|
	return remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
 | 
						|
			       vma->vm_end - vma->vm_start,
 | 
						|
			       vma->vm_page_prot);
 | 
						|
}
 | 
						|
 | 
						|
#ifndef CONFIG_GENERIC_IOMAP
 | 
						|
 | 
						|
void __iomem *__pci_ioport_map(struct pci_dev *dev,
 | 
						|
			       unsigned long port, unsigned int nr)
 | 
						|
{
 | 
						|
	struct pci_channel *chan = dev->sysdata;
 | 
						|
 | 
						|
	if (unlikely(!chan->io_map_base)) {
 | 
						|
		chan->io_map_base = sh_io_port_base;
 | 
						|
 | 
						|
		if (pci_domains_supported)
 | 
						|
			panic("To avoid data corruption io_map_base MUST be "
 | 
						|
			      "set with multiple PCI domains.");
 | 
						|
	}
 | 
						|
 | 
						|
	return (void __iomem *)(chan->io_map_base + port);
 | 
						|
}
 | 
						|
 | 
						|
void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
 | 
						|
{
 | 
						|
	iounmap(addr);
 | 
						|
}
 | 
						|
EXPORT_SYMBOL(pci_iounmap);
 | 
						|
 | 
						|
#endif /* CONFIG_GENERIC_IOMAP */
 | 
						|
 | 
						|
EXPORT_SYMBOL(PCIBIOS_MIN_IO);
 | 
						|
EXPORT_SYMBOL(PCIBIOS_MIN_MEM);
 |