original_kernel/arch/csky/mm/ioremap.c

49 lines
1.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/io.h>
#include <asm/pgtable.h>
void __iomem *ioremap(phys_addr_t addr, size_t size)
{
phys_addr_t last_addr;
unsigned long offset, vaddr;
struct vm_struct *area;
pgprot_t prot;
last_addr = addr + size - 1;
if (!size || last_addr < addr)
return NULL;
offset = addr & (~PAGE_MASK);
addr &= PAGE_MASK;
size = PAGE_ALIGN(size + offset);
area = get_vm_area_caller(size, VM_ALLOC, __builtin_return_address(0));
if (!area)
return NULL;
vaddr = (unsigned long)area->addr;
prot = __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE |
_PAGE_GLOBAL | _CACHE_UNCACHED);
if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) {
free_vm_area(area);
return NULL;
}
return (void __iomem *)(vaddr + offset);
}
EXPORT_SYMBOL(ioremap);
void iounmap(void __iomem *addr)
{
vunmap((void *)((unsigned long)addr & PAGE_MASK));
}
EXPORT_SYMBOL(iounmap);