mirror of
https://github.com/torvalds/linux
synced 2024-10-08 20:34:15 +00:00
9f76779f24
To make PCI IO work we need to properly virtually map IO cpu physical address and set this virtual address as the address of the first PCI IO port which is set using function 'set_io_port_base()'. Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com> Link: https://lore.kernel.org/r/20210925203224.10419-6-sergio.paracuellos@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
63 lines
1.7 KiB
C
63 lines
1.7 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* Copyright (C) 2016 Imagination Technologies
|
|
* Author: Paul Burton <paul.burton@mips.com>
|
|
*
|
|
* pcibios_align_resource taken from arch/arm/kernel/bios32.c.
|
|
*/
|
|
|
|
#include <linux/pci.h>
|
|
|
|
/*
|
|
* 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;
|
|
resource_size_t start = res->start;
|
|
struct pci_host_bridge *host_bridge;
|
|
|
|
if (res->flags & IORESOURCE_IO && start & 0x300)
|
|
start = (start + 0x3ff) & ~0x3ff;
|
|
|
|
start = (start + align - 1) & ~(align - 1);
|
|
|
|
host_bridge = pci_find_host_bridge(dev->bus);
|
|
|
|
if (host_bridge->align_resource)
|
|
return host_bridge->align_resource(dev, res,
|
|
start, size, align);
|
|
|
|
return start;
|
|
}
|
|
|
|
void pcibios_fixup_bus(struct pci_bus *bus)
|
|
{
|
|
pci_read_bridge_bases(bus);
|
|
}
|
|
|
|
int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
|
|
{
|
|
unsigned long vaddr;
|
|
|
|
if (res->start != 0) {
|
|
WARN_ONCE(1, "resource start address is not zero\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
vaddr = (unsigned long)ioremap(phys_addr, resource_size(res));
|
|
set_io_port_base(vaddr);
|
|
return 0;
|
|
}
|