arch/mips/lib/iomap-pci.c

Source file repositories/reference/linux-study-clean/arch/mips/lib/iomap-pci.c

File Facts

System
Linux kernel
Corpus path
arch/mips/lib/iomap-pci.c
Extension
.c
Size
1624 bytes
Lines
57
Domain
Architecture Layer
Bucket
arch/mips
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
/*
 * Implement the default iomap interfaces
 *
 * (C) Copyright 2004 Linus Torvalds
 * (C) Copyright 2006 Ralf Baechle <ralf@linux-mips.org>
 * (C) Copyright 2007 MIPS Technologies, Inc.
 *     written by Ralf Baechle <ralf@linux-mips.org>
 */
#include <linux/pci.h>
#include <linux/export.h>
#include <asm/io.h>

#ifdef CONFIG_PCI_DRIVERS_LEGACY

void __iomem *__pci_ioport_map(struct pci_dev *dev,
			       unsigned long port, unsigned int nr)
{
	struct pci_controller *ctrl = dev->bus->sysdata;
	unsigned long base = ctrl->io_map_base;

	/* This will eventually become a BUG_ON but for now be gentle */
	if (unlikely(!ctrl->io_map_base)) {
		struct pci_bus *bus = dev->bus;
		char name[8];

		while (bus->parent)
			bus = bus->parent;

		ctrl->io_map_base = base = mips_io_port_base;

		sprintf(name, "%04x:%02x", pci_domain_nr(bus), bus->number);
		printk(KERN_WARNING "io_map_base of root PCI bus %s unset.  "
		       "Trying to continue but you better\nfix this issue or "
		       "report it to linux-mips@vger.kernel.org or your "
		       "vendor.\n", name);
#ifdef CONFIG_PCI_DOMAINS
		panic("To avoid data corruption io_map_base MUST be set with "
		      "multiple PCI domains.");
#endif
	}

	return (void __iomem *) (ctrl->io_map_base + port);
}

void pci_iounmap(struct pci_dev *dev, void __iomem *addr)
{
	struct pci_controller *ctrl = dev->bus->sysdata;
	void __iomem *base = (void __iomem *)ctrl->io_map_base;

	if (addr < base || addr > (base + resource_size(ctrl->io_resource)))
		iounmap(addr);
}
EXPORT_SYMBOL(pci_iounmap);

#endif /* CONFIG_PCI_DRIVERS_LEGACY */

Annotation

Implementation Notes