90e7d649d8
This implements a fairly significant overhaul of the dynamic PMB mapping code. The primary change here is that the PMB gets its own VMA that follows the uncached mapping and we attempt to be a bit more intelligent with dynamic sizing, multi-entry mapping, and so forth. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
136 lines
2.6 KiB
C
136 lines
2.6 KiB
C
/*
|
|
* Re-map IO memory to kernel address space so that we can access it.
|
|
*
|
|
* These functions should only be used when it is necessary to map a
|
|
* physical address space into the kernel address space before ioremap()
|
|
* can be used, e.g. early in boot before paging_init().
|
|
*
|
|
* Copyright (C) 2009 Matt Fleming
|
|
*/
|
|
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/ioport.h>
|
|
#include <linux/module.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/io.h>
|
|
#include <linux/bootmem.h>
|
|
#include <linux/proc_fs.h>
|
|
#include <linux/slab.h>
|
|
#include <asm/fixmap.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>
|
|
#include <asm/mmu_context.h>
|
|
|
|
struct ioremap_map {
|
|
void __iomem *addr;
|
|
unsigned long size;
|
|
unsigned long fixmap_addr;
|
|
};
|
|
|
|
static struct ioremap_map ioremap_maps[FIX_N_IOREMAPS];
|
|
|
|
void __init ioremap_fixed_init(void)
|
|
{
|
|
struct ioremap_map *map;
|
|
int i;
|
|
|
|
for (i = 0; i < FIX_N_IOREMAPS; i++) {
|
|
map = &ioremap_maps[i];
|
|
map->fixmap_addr = __fix_to_virt(FIX_IOREMAP_BEGIN + i);
|
|
}
|
|
}
|
|
|
|
void __init __iomem *
|
|
ioremap_fixed(phys_addr_t phys_addr, unsigned long size, pgprot_t prot)
|
|
{
|
|
enum fixed_addresses idx0, idx;
|
|
struct ioremap_map *map;
|
|
unsigned int nrpages;
|
|
unsigned long offset;
|
|
int i, slot;
|
|
|
|
/*
|
|
* Mappings have to be page-aligned
|
|
*/
|
|
offset = phys_addr & ~PAGE_MASK;
|
|
phys_addr &= PAGE_MASK;
|
|
size = PAGE_ALIGN(phys_addr + size) - phys_addr;
|
|
|
|
slot = -1;
|
|
for (i = 0; i < FIX_N_IOREMAPS; i++) {
|
|
map = &ioremap_maps[i];
|
|
if (!map->addr) {
|
|
map->size = size;
|
|
slot = i;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (slot < 0)
|
|
return NULL;
|
|
|
|
/*
|
|
* Mappings have to fit in the FIX_IOREMAP area.
|
|
*/
|
|
nrpages = size >> PAGE_SHIFT;
|
|
if (nrpages > FIX_N_IOREMAPS)
|
|
return NULL;
|
|
|
|
/*
|
|
* Ok, go for it..
|
|
*/
|
|
idx0 = FIX_IOREMAP_BEGIN + slot;
|
|
idx = idx0;
|
|
while (nrpages > 0) {
|
|
pgprot_val(prot) |= _PAGE_WIRED;
|
|
__set_fixmap(idx, phys_addr, prot);
|
|
phys_addr += PAGE_SIZE;
|
|
idx++;
|
|
--nrpages;
|
|
}
|
|
|
|
map->addr = (void __iomem *)(offset + map->fixmap_addr);
|
|
return map->addr;
|
|
}
|
|
|
|
int iounmap_fixed(void __iomem *addr)
|
|
{
|
|
enum fixed_addresses idx;
|
|
struct ioremap_map *map;
|
|
unsigned int nrpages;
|
|
int i, slot;
|
|
|
|
slot = -1;
|
|
for (i = 0; i < FIX_N_IOREMAPS; i++) {
|
|
map = &ioremap_maps[i];
|
|
if (map->addr == addr) {
|
|
slot = i;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* If we don't match, it's not for us.
|
|
*/
|
|
if (slot < 0)
|
|
return -EINVAL;
|
|
|
|
nrpages = map->size >> PAGE_SHIFT;
|
|
|
|
idx = FIX_IOREMAP_BEGIN + slot + nrpages - 1;
|
|
while (nrpages > 0) {
|
|
__clear_fixmap(idx, __pgprot(_PAGE_WIRED));
|
|
--idx;
|
|
--nrpages;
|
|
}
|
|
|
|
map->size = 0;
|
|
map->addr = NULL;
|
|
|
|
return 0;
|
|
}
|