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/*
* linux/arch/m68k/mm/kmap.c
*
* Copyright (C) 1997 Roman Hodek
*
* 10/01/99 cleaned up the code and changing to the same interface
* used by other architectures /Roman Zippel
*/
#include <linux/config.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <asm/setup.h>
#include <asm/segment.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/io.h>
#include <asm/system.h>
#undef DEBUG
#define PTRTREESIZE (256*1024)
/*
* For 040/060 we can use the virtual memory area like other architectures,
* but for 020/030 we want to use early termination page descriptor and we
* can't mix this with normal page descriptors, so we have to copy that code
* (mm/vmalloc.c) and return appriorate aligned addresses.
*/
#ifdef CPU_M68040_OR_M68060_ONLY
#define IO_SIZE PAGE_SIZE
static inline struct vm_struct *get_io_area(unsigned long size)
{
return get_vm_area(size, VM_IOREMAP);
}
static inline void free_io_area(void *addr)
{
return vfree((void *)(PAGE_MASK & (unsigned long)addr));
}
#else
#define IO_SIZE (256*1024)
static struct vm_struct *iolist = NULL;
static struct vm_struct *get_io_area(unsigned long size)
{
unsigned long addr;
struct vm_struct **p, *tmp, *area;
area = (struct vm_struct *)kmalloc(sizeof(*area), GFP_KERNEL);
if (!area)
return NULL;
addr = KMAP_START;
for (p = &iolist; (tmp = *p) ; p = &tmp->next) {
if (size + addr < (unsigned long)tmp->addr)
break;
if (addr > KMAP_END-size)
return NULL;
addr = tmp->size + (unsigned long)tmp->addr;
}
area->addr = (void *)addr;
area->size = size + IO_SIZE;
area->next = *p;
*p = area;
return area;
}
static inline void free_io_area(void *addr)
{
struct vm_struct **p, *tmp;
if (!addr)
return;
addr = (void *)((unsigned long)addr & -IO_SIZE);
for (p = &iolist ; (tmp = *p) ; p = &tmp->next) {
if (tmp->addr == addr) {
*p = tmp->next;
__iounmap(tmp->addr, tmp->size);
kfree(tmp);
return;
}
}
}
#endif
/*
* Map some physical address range into the kernel address space. The
* code is copied and adapted from map_chunk().
*/
/* Rewritten by Andreas Schwab to remove all races. */
void *__ioremap(unsigned long physaddr, unsigned long size, int cacheflag)
{
struct vm_struct *area;
unsigned long virtaddr, retaddr;
long offset;
pgd_t *pgd_dir;
pmd_t *pmd_dir;
pte_t *pte_dir;
/*
* Don't allow mappings that wrap..
*/
if (!size || size > physaddr + size)
return NULL;
#ifdef CONFIG_AMIGA
if (MACH_IS_AMIGA) {
if ((physaddr >= 0x40000000) && (physaddr + size < 0x60000000)
&& (cacheflag == IOMAP_NOCACHE_SER))
return (void *)physaddr;
}
#endif
#ifdef DEBUG
printk("ioremap: 0x%lx,0x%lx(%d) - ", physaddr, size, cacheflag);
#endif
/*
* Mappings have to be aligned
*/
offset = physaddr & (IO_SIZE - 1);
physaddr &= -IO_SIZE;
size = (size + offset + IO_SIZE - 1) & -IO_SIZE;
/*
* Ok, go for it..
*/
area = get_io_area(size);
if (!area)
return NULL;
virtaddr = (unsigned long)area->addr;
retaddr = virtaddr + offset;
#ifdef DEBUG
printk("0x%lx,0x%lx,0x%lx", physaddr, virtaddr, retaddr);
#endif
/*
* add cache and table flags to physical address
*/
if (CPU_IS_040_OR_060) {
physaddr |= (_PAGE_PRESENT | _PAGE_GLOBAL040 |
_PAGE_ACCESSED | _PAGE_DIRTY);
switch (cacheflag) {
case IOMAP_FULL_CACHING:
physaddr |= _PAGE_CACHE040;
break;
case IOMAP_NOCACHE_SER:
default:
physaddr |= _PAGE_NOCACHE_S;
break;
case IOMAP_NOCACHE_NONSER:
physaddr |= _PAGE_NOCACHE;
break;
case IOMAP_WRITETHROUGH:
physaddr |= _PAGE_CACHE040W;
break;
}
} else {
physaddr |= (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY);
switch (cacheflag) {
case IOMAP_NOCACHE_SER:
case IOMAP_NOCACHE_NONSER:
default:
physaddr |= _PAGE_NOCACHE030;
break;
case IOMAP_FULL_CACHING:
case IOMAP_WRITETHROUGH:
break;
}
}
while ((long)size > 0) {
#ifdef DEBUG
if (!(virtaddr & (PTRTREESIZE-1)))
printk ("\npa=%#lx va=%#lx ", physaddr, virtaddr);
#endif
pgd_dir = pgd_offset_k(virtaddr);
pmd_dir = pmd_alloc_kernel(pgd_dir, virtaddr);
if (!pmd_dir) {
printk("ioremap: no mem for pmd_dir\n");
return NULL;
}
if (CPU_IS_020_OR_030) {
pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr;
physaddr += PTRTREESIZE;
virtaddr += PTRTREESIZE;
size -= PTRTREESIZE;
} else {
pte_dir = pte_alloc_kernel(pmd_dir, virtaddr);
if (!pte_dir) {
printk("ioremap: no mem for pte_dir\n");
return NULL;
}
pte_val(*pte_dir) = physaddr;
virtaddr += PAGE_SIZE;
physaddr += PAGE_SIZE;
size -= PAGE_SIZE;
}
}
#ifdef DEBUG
printk("\n");
#endif
flush_tlb_all();
return (void *)retaddr;
}
/*
* Unmap a ioremap()ed region again
*/
void iounmap(void *addr)
{
#ifdef CONFIG_AMIGA
if ((!MACH_IS_AMIGA) ||
(((unsigned long)addr < 0x40000000) ||
((unsigned long)addr > 0x60000000)))
free_io_area(addr);
#else
free_io_area(addr);
#endif
}
/*
* __iounmap unmaps nearly everything, so be careful
* it doesn't free currently pointer/page tables anymore but it
* wans't used anyway and might be added later.
*/
void __iounmap(void *addr, unsigned long size)
{
unsigned long virtaddr = (unsigned long)addr;
pgd_t *pgd_dir;
pmd_t *pmd_dir;
pte_t *pte_dir;
while ((long)size > 0) {
pgd_dir = pgd_offset_k(virtaddr);
if (pgd_bad(*pgd_dir)) {
printk("iounmap: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
pgd_clear(pgd_dir);
return;
}
pmd_dir = pmd_offset(pgd_dir, virtaddr);
if (CPU_IS_020_OR_030) {
int pmd_off = (virtaddr/PTRTREESIZE) & 15;
if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) {
pmd_dir->pmd[pmd_off] = 0;
virtaddr += PTRTREESIZE;
size -= PTRTREESIZE;
continue;
}
}
if (pmd_bad(*pmd_dir)) {
printk("iounmap: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
pmd_clear(pmd_dir);
return;
}
pte_dir = pte_offset(pmd_dir, virtaddr);
pte_val(*pte_dir) = 0;
virtaddr += PAGE_SIZE;
size -= PAGE_SIZE;
}
flush_tlb_all();
}
/*
* Set new cache mode for some kernel address space.
* The caller must push data for that range itself, if such data may already
* be in the cache.
*/
void kernel_set_cachemode(void *addr, unsigned long size, int cmode)
{
unsigned long virtaddr = (unsigned long)addr;
pgd_t *pgd_dir;
pmd_t *pmd_dir;
pte_t *pte_dir;
if (CPU_IS_040_OR_060) {
switch (cmode) {
case IOMAP_FULL_CACHING:
cmode = _PAGE_CACHE040;
break;
case IOMAP_NOCACHE_SER:
default:
cmode = _PAGE_NOCACHE_S;
break;
case IOMAP_NOCACHE_NONSER:
cmode = _PAGE_NOCACHE;
break;
case IOMAP_WRITETHROUGH:
cmode = _PAGE_CACHE040W;
break;
}
} else {
switch (cmode) {
case IOMAP_NOCACHE_SER:
case IOMAP_NOCACHE_NONSER:
default:
cmode = _PAGE_NOCACHE030;
break;
case IOMAP_FULL_CACHING:
case IOMAP_WRITETHROUGH:
cmode = 0;
}
}
while ((long)size > 0) {
pgd_dir = pgd_offset_k(virtaddr);
if (pgd_bad(*pgd_dir)) {
printk("iocachemode: bad pgd(%08lx)\n", pgd_val(*pgd_dir));
pgd_clear(pgd_dir);
return;
}
pmd_dir = pmd_offset(pgd_dir, virtaddr);
if (CPU_IS_020_OR_030) {
int pmd_off = (virtaddr/PTRTREESIZE) & 15;
if ((pmd_dir->pmd[pmd_off] & _DESCTYPE_MASK) == _PAGE_PRESENT) {
pmd_dir->pmd[pmd_off] = (pmd_dir->pmd[pmd_off] &
_CACHEMASK040) | cmode;
virtaddr += PTRTREESIZE;
size -= PTRTREESIZE;
continue;
}
}
if (pmd_bad(*pmd_dir)) {
printk("iocachemode: bad pmd (%08lx)\n", pmd_val(*pmd_dir));
pmd_clear(pmd_dir);
return;
}
pte_dir = pte_offset(pmd_dir, virtaddr);
pte_val(*pte_dir) = (pte_val(*pte_dir) & _CACHEMASK040) | cmode;
virtaddr += PAGE_SIZE;
size -= PAGE_SIZE;
}
flush_tlb_all();
}
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