satip-axe/kernel/arch/sh/mm/ioremap_32.c
2015-03-26 17:24:57 +01:00

149 lines
3.8 KiB
C

/*
* arch/sh/mm/ioremap.c
*
* 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
*
* (C) Copyright 1995 1996 Linus Torvalds
* (C) Copyright 2005, 2006 Paul Mundt
*
* 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/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.
*
* 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.
*/
static void __iomem *__ioremap_prot(unsigned long phys_addr, unsigned long size,
pgprot_t pgprot)
{
struct vm_struct * area;
unsigned long offset, last_addr, addr;
int simple = (pgprot_val(pgprot) == pgprot_val(PAGE_KERNEL)) ||
(pgprot_val(pgprot) == pgprot_val(PAGE_KERNEL_NOCACHE));
int cached = pgprot_val(pgprot) & _PAGE_CACHABLE;
/* Don't allow wraparound or zero size */
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr)
return NULL;
/*
* If we're in the fixed PCI memory range, mapping through page
* tables is not only pointless, but also fundamentally broken.
* Just return the physical address instead.
*
* For boards that map a small PCI memory aperture somewhere in
* P1/P2 space, ioremap() will already do the right thing,
* and we'll never get this far.
*/
if (is_pci_memory_fixed_range(phys_addr, size))
return (void __iomem *)phys_addr;
/*
* Don't allow anybody to remap normal RAM that we're using..
*/
if ((phys_addr >= __pa(memory_start)) && (last_addr < __pa(memory_end))) {
char *t_addr, *t_end;
struct page *page;
t_addr = __va(phys_addr);
t_end = t_addr + (size - 1);
for(page = virt_to_page(t_addr); page <= virt_to_page(t_end); page++)
if(!PageReserved(page))
return NULL;
}
/* P4 uncached addresses are permanently mapped */
if ((PXSEG(phys_addr) == P4SEG) && simple && !cached)
return (void __iomem *)phys_addr;
/*
* Mappings have to be page-aligned
*/
offset = phys_addr & ~PAGE_MASK;
phys_addr &= PAGE_MASK;
size = PAGE_ALIGN(last_addr+1) - phys_addr;
#ifdef CONFIG_PMB
addr = pmb_remap(phys_addr, size, cached ? _PAGE_CACHABLE : 0);
if (addr)
return (void __iomem *)(offset + (char *)addr);
#endif
area = get_vm_area(size, VM_IOREMAP);
if (!area)
return NULL;
area->phys_addr = phys_addr;
addr = (unsigned long)area->addr;
if (ioremap_page_range(addr, addr + size, phys_addr, pgprot)) {
vunmap((void *)addr);
return NULL;
}
return (void __iomem *)(offset + (char *)addr);
}
void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
unsigned long flags)
{
pgprot_t pgprot;
if (unlikely(flags & _PAGE_CACHABLE))
pgprot = PAGE_KERNEL;
else
pgprot = PAGE_KERNEL_NOCACHE;
return __ioremap_prot(phys_addr, size, pgprot);
}
EXPORT_SYMBOL(__ioremap);
void __iounmap(void __iomem *addr)
{
unsigned long vaddr = (unsigned long __force)addr;
unsigned long seg = PXSEG(vaddr);
struct vm_struct *p;
if (seg == P4SEG || is_pci_memory_fixed_range(vaddr, 0))
return;
#ifdef CONFIG_29BIT
if (seg < P3SEG)
return;
#endif
#ifdef CONFIG_PMB
if (pmb_unmap(vaddr))
return;
#endif
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);