mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-15 00:04:15 +08:00
138 lines
3.2 KiB
C
138 lines
3.2 KiB
C
/*
|
|
* arch/sh/mm/ioremap.c
|
|
*
|
|
* (C) Copyright 1995 1996 Linus Torvalds
|
|
* (C) Copyright 2005 - 2010 Paul Mundt
|
|
*
|
|
* Re-map IO memory to kernel address space so that we can access it.
|
|
* This is needed for high PCI addresses that aren't mapped in the
|
|
* 640k-1MB IO memory area on PC's
|
|
*
|
|
* 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/vmalloc.h>
|
|
#include <linux/module.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/io.h>
|
|
#include <asm/page.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/addrspace.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/tlbflush.h>
|
|
#include <asm/mmu.h>
|
|
|
|
/*
|
|
* Remap an arbitrary physical address space into the kernel virtual
|
|
* address space. Needed when the kernel wants to access high addresses
|
|
* directly.
|
|
*
|
|
* NOTE! We need to allow non-page-aligned mappings too: we will obviously
|
|
* have to convert them into an offset in a page-aligned mapping, but the
|
|
* caller shouldn't need to know that small detail.
|
|
*/
|
|
void __iomem * __ref
|
|
__ioremap_caller(phys_addr_t phys_addr, unsigned long size,
|
|
pgprot_t pgprot, void *caller)
|
|
{
|
|
struct vm_struct *area;
|
|
unsigned long offset, last_addr, addr, orig_addr;
|
|
void __iomem *mapped;
|
|
|
|
/* Don't allow wraparound or zero size */
|
|
last_addr = phys_addr + size - 1;
|
|
if (!size || last_addr < phys_addr)
|
|
return NULL;
|
|
|
|
/*
|
|
* If we can't yet use the regular approach, go the fixmap route.
|
|
*/
|
|
if (!mem_init_done)
|
|
return ioremap_fixed(phys_addr, size, pgprot);
|
|
|
|
/*
|
|
* First try to remap through the PMB.
|
|
* PMB entries are all pre-faulted.
|
|
*/
|
|
mapped = pmb_remap_caller(phys_addr, size, pgprot, caller);
|
|
if (mapped && !IS_ERR(mapped))
|
|
return mapped;
|
|
|
|
/*
|
|
* Mappings have to be page-aligned
|
|
*/
|
|
offset = phys_addr & ~PAGE_MASK;
|
|
phys_addr &= PAGE_MASK;
|
|
size = PAGE_ALIGN(last_addr+1) - phys_addr;
|
|
|
|
/*
|
|
* Ok, go for it..
|
|
*/
|
|
area = get_vm_area_caller(size, VM_IOREMAP, caller);
|
|
if (!area)
|
|
return NULL;
|
|
area->phys_addr = phys_addr;
|
|
orig_addr = addr = (unsigned long)area->addr;
|
|
|
|
if (ioremap_page_range(addr, addr + size, phys_addr, pgprot)) {
|
|
vunmap((void *)orig_addr);
|
|
return NULL;
|
|
}
|
|
|
|
return (void __iomem *)(offset + (char *)orig_addr);
|
|
}
|
|
EXPORT_SYMBOL(__ioremap_caller);
|
|
|
|
/*
|
|
* Simple checks for non-translatable mappings.
|
|
*/
|
|
static inline int iomapping_nontranslatable(unsigned long offset)
|
|
{
|
|
#ifdef CONFIG_29BIT
|
|
/*
|
|
* In 29-bit mode this includes the fixed P1/P2 areas, as well as
|
|
* parts of P3.
|
|
*/
|
|
if (PXSEG(offset) < P3SEG || offset >= P3_ADDR_MAX)
|
|
return 1;
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
void iounmap(void __iomem *addr)
|
|
{
|
|
unsigned long vaddr = (unsigned long __force)addr;
|
|
struct vm_struct *p;
|
|
|
|
/*
|
|
* Nothing to do if there is no translatable mapping.
|
|
*/
|
|
if (iomapping_nontranslatable(vaddr))
|
|
return;
|
|
|
|
/*
|
|
* There's no VMA if it's from an early fixed mapping.
|
|
*/
|
|
if (iounmap_fixed(addr) == 0)
|
|
return;
|
|
|
|
/*
|
|
* If the PMB handled it, there's nothing else to do.
|
|
*/
|
|
if (pmb_unmap(addr) == 0)
|
|
return;
|
|
|
|
p = remove_vm_area((void *)(vaddr & PAGE_MASK));
|
|
if (!p) {
|
|
printk(KERN_ERR "%s: bad address %p\n", __func__, addr);
|
|
return;
|
|
}
|
|
|
|
kfree(p);
|
|
}
|
|
EXPORT_SYMBOL(iounmap);
|