linux/arch/sh64/mm/ioremap.c

468 lines
11 KiB
C
Raw Normal View History

/*
* 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.
*
* arch/sh64/mm/ioremap.c
*
* Copyright (C) 2000, 2001 Paolo Alberelli
* Copyright (C) 2003, 2004 Paul Mundt
*
* Mostly derived from arch/sh/mm/ioremap.c which, in turn is mostly
* derived from arch/i386/mm/ioremap.c .
*
* (C) Copyright 1995 1996 Linus Torvalds
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/sched.h>
#include <linux/string.h>
#include <asm/io.h>
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
#include <linux/ioport.h>
#include <linux/bootmem.h>
#include <linux/proc_fs.h>
static void shmedia_mapioaddr(unsigned long, unsigned long);
static unsigned long shmedia_ioremap(struct resource *, u32, int);
static inline void remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
unsigned long phys_addr, unsigned long flags)
{
unsigned long end;
unsigned long pfn;
pgprot_t pgprot = __pgprot(_PAGE_PRESENT | _PAGE_READ |
_PAGE_WRITE | _PAGE_DIRTY |
_PAGE_ACCESSED | _PAGE_SHARED | flags);
address &= ~PMD_MASK;
end = address + size;
if (end > PMD_SIZE)
end = PMD_SIZE;
if (address >= end)
BUG();
pfn = phys_addr >> PAGE_SHIFT;
pr_debug(" %s: pte %p address %lx size %lx phys_addr %lx\n",
__FUNCTION__,pte,address,size,phys_addr);
do {
if (!pte_none(*pte)) {
printk("remap_area_pte: page already exists\n");
BUG();
}
set_pte(pte, pfn_pte(pfn, pgprot));
address += PAGE_SIZE;
pfn++;
pte++;
} while (address && (address < end));
}
static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
unsigned long phys_addr, unsigned long flags)
{
unsigned long end;
address &= ~PGDIR_MASK;
end = address + size;
if (end > PGDIR_SIZE)
end = PGDIR_SIZE;
phys_addr -= address;
if (address >= end)
BUG();
do {
[PATCH] mm: init_mm without ptlock First step in pushing down the page_table_lock. init_mm.page_table_lock has been used throughout the architectures (usually for ioremap): not to serialize kernel address space allocation (that's usually vmlist_lock), but because pud_alloc,pmd_alloc,pte_alloc_kernel expect caller holds it. Reverse that: don't lock or unlock init_mm.page_table_lock in any of the architectures; instead rely on pud_alloc,pmd_alloc,pte_alloc_kernel to take and drop it when allocating a new one, to check lest a racing task already did. Similarly no page_table_lock in vmalloc's map_vm_area. Some temporary ugliness in __pud_alloc and __pmd_alloc: since they also handle user mms, which are converted only by a later patch, for now they have to lock differently according to whether or not it's init_mm. If sources get muddled, there's a danger that an arch source taking init_mm.page_table_lock will be mixed with common source also taking it (or neither take it). So break the rules and make another change, which should break the build for such a mismatch: remove the redundant mm arg from pte_alloc_kernel (ppc64 scrapped its distinct ioremap_mm in 2.6.13). Exceptions: arm26 used pte_alloc_kernel on user mm, now pte_alloc_map; ia64 used pte_alloc_map on init_mm, now pte_alloc_kernel; parisc had bad args to pmd_alloc and pte_alloc_kernel in unused USE_HPPA_IOREMAP code; ppc64 map_io_page forgot to unlock on failure; ppc mmu_mapin_ram and ppc64 im_free took page_table_lock for no good reason. Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30 01:16:21 +00:00
pte_t * pte = pte_alloc_kernel(pmd, address);
if (!pte)
return -ENOMEM;
remap_area_pte(pte, address, end - address, address + phys_addr, flags);
address = (address + PMD_SIZE) & PMD_MASK;
pmd++;
} while (address && (address < end));
return 0;
}
static int remap_area_pages(unsigned long address, unsigned long phys_addr,
unsigned long size, unsigned long flags)
{
int error;
pgd_t * dir;
unsigned long end = address + size;
phys_addr -= address;
dir = pgd_offset_k(address);
flush_cache_all();
if (address >= end)
BUG();
do {
pmd_t *pmd = pmd_alloc(&init_mm, dir, address);
error = -ENOMEM;
if (!pmd)
break;
if (remap_area_pmd(pmd, address, end - address,
phys_addr + address, flags)) {
break;
}
error = 0;
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
flush_tlb_all();
return 0;
}
/*
* Generic mapping function (not visible outside):
*/
/*
* 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 * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
{
void * addr;
struct vm_struct * area;
unsigned long offset, last_addr;
/* Don't allow wraparound or zero size */
last_addr = phys_addr + size - 1;
if (!size || last_addr < phys_addr)
return NULL;
/*
* 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(size, VM_IOREMAP);
pr_debug("Get vm_area returns %p addr %p\n",area,area->addr);
if (!area)
return NULL;
area->phys_addr = phys_addr;
addr = area->addr;
if (remap_area_pages((unsigned long)addr, phys_addr, size, flags)) {
vunmap(addr);
return NULL;
}
return (void *) (offset + (char *)addr);
}
void iounmap(void *addr)
{
struct vm_struct *area;
vfree((void *) (PAGE_MASK & (unsigned long) addr));
area = remove_vm_area((void *) (PAGE_MASK & (unsigned long) addr));
if (!area) {
printk(KERN_ERR "iounmap: bad address %p\n", addr);
return;
}
kfree(area);
}
static struct resource shmedia_iomap = {
.name = "shmedia_iomap",
.start = IOBASE_VADDR + PAGE_SIZE,
.end = IOBASE_END - 1,
};
static void shmedia_mapioaddr(unsigned long pa, unsigned long va);
static void shmedia_unmapioaddr(unsigned long vaddr);
static unsigned long shmedia_ioremap(struct resource *res, u32 pa, int sz);
/*
* We have the same problem as the SPARC, so lets have the same comment:
* Our mini-allocator...
* Boy this is gross! We need it because we must map I/O for
* timers and interrupt controller before the kmalloc is available.
*/
#define XNMLN 15
#define XNRES 10
struct xresource {
struct resource xres; /* Must be first */
int xflag; /* 1 == used */
char xname[XNMLN+1];
};
static struct xresource xresv[XNRES];
static struct xresource *xres_alloc(void)
{
struct xresource *xrp;
int n;
xrp = xresv;
for (n = 0; n < XNRES; n++) {
if (xrp->xflag == 0) {
xrp->xflag = 1;
return xrp;
}
xrp++;
}
return NULL;
}
static void xres_free(struct xresource *xrp)
{
xrp->xflag = 0;
}
static struct resource *shmedia_find_resource(struct resource *root,
unsigned long vaddr)
{
struct resource *res;
for (res = root->child; res; res = res->sibling)
if (res->start <= vaddr && res->end >= vaddr)
return res;
return NULL;
}
static unsigned long shmedia_alloc_io(unsigned long phys, unsigned long size,
const char *name)
{
static int printed_full = 0;
struct xresource *xres;
struct resource *res;
char *tack;
int tlen;
if (name == NULL) name = "???";
if ((xres = xres_alloc()) != 0) {
tack = xres->xname;
res = &xres->xres;
} else {
if (!printed_full) {
printk("%s: done with statics, switching to kmalloc\n",
__FUNCTION__);
printed_full = 1;
}
tlen = strlen(name);
tack = kmalloc(sizeof (struct resource) + tlen + 1, GFP_KERNEL);
if (!tack)
return -ENOMEM;
memset(tack, 0, sizeof(struct resource));
res = (struct resource *) tack;
tack += sizeof (struct resource);
}
strncpy(tack, name, XNMLN);
tack[XNMLN] = 0;
res->name = tack;
return shmedia_ioremap(res, phys, size);
}
static unsigned long shmedia_ioremap(struct resource *res, u32 pa, int sz)
{
unsigned long offset = ((unsigned long) pa) & (~PAGE_MASK);
unsigned long round_sz = (offset + sz + PAGE_SIZE-1) & PAGE_MASK;
unsigned long va;
unsigned int psz;
if (allocate_resource(&shmedia_iomap, res, round_sz,
shmedia_iomap.start, shmedia_iomap.end,
PAGE_SIZE, NULL, NULL) != 0) {
panic("alloc_io_res(%s): cannot occupy\n",
(res->name != NULL)? res->name: "???");
}
va = res->start;
pa &= PAGE_MASK;
psz = (res->end - res->start + (PAGE_SIZE - 1)) / PAGE_SIZE;
/* log at boot time ... */
printk("mapioaddr: %6s [%2d page%s] va 0x%08lx pa 0x%08x\n",
((res->name != NULL) ? res->name : "???"),
psz, psz == 1 ? " " : "s", va, pa);
for (psz = res->end - res->start + 1; psz != 0; psz -= PAGE_SIZE) {
shmedia_mapioaddr(pa, va);
va += PAGE_SIZE;
pa += PAGE_SIZE;
}
res->start += offset;
res->end = res->start + sz - 1; /* not strictly necessary.. */
return res->start;
}
static void shmedia_free_io(struct resource *res)
{
unsigned long len = res->end - res->start + 1;
BUG_ON((len & (PAGE_SIZE - 1)) != 0);
while (len) {
len -= PAGE_SIZE;
shmedia_unmapioaddr(res->start + len);
}
release_resource(res);
}
static void *sh64_get_page(void)
{
extern int after_bootmem;
void *page;
if (after_bootmem) {
page = (void *)get_zeroed_page(GFP_ATOMIC);
} else {
page = alloc_bootmem_pages(PAGE_SIZE);
}
if (!page || ((unsigned long)page & ~PAGE_MASK))
panic("sh64_get_page: Out of memory already?\n");
return page;
}
static void shmedia_mapioaddr(unsigned long pa, unsigned long va)
{
pgd_t *pgdp;
pmd_t *pmdp;
pte_t *ptep, pte;
pgprot_t prot;
unsigned long flags = 1; /* 1 = CB0-1 device */
pr_debug("shmedia_mapiopage pa %08lx va %08lx\n", pa, va);
pgdp = pgd_offset_k(va);
if (pgd_none(*pgdp) || !pgd_present(*pgdp)) {
pmdp = (pmd_t *)sh64_get_page();
set_pgd(pgdp, __pgd((unsigned long)pmdp | _KERNPG_TABLE));
}
pmdp = pmd_offset(pgdp, va);
if (pmd_none(*pmdp) || !pmd_present(*pmdp) ) {
ptep = (pte_t *)sh64_get_page();
set_pmd(pmdp, __pmd((unsigned long)ptep + _PAGE_TABLE));
}
prot = __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE |
_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_SHARED | flags);
pte = pfn_pte(pa >> PAGE_SHIFT, prot);
ptep = pte_offset_kernel(pmdp, va);
if (!pte_none(*ptep) &&
pte_val(*ptep) != pte_val(pte))
pte_ERROR(*ptep);
set_pte(ptep, pte);
flush_tlb_kernel_range(va, PAGE_SIZE);
}
static void shmedia_unmapioaddr(unsigned long vaddr)
{
pgd_t *pgdp;
pmd_t *pmdp;
pte_t *ptep;
pgdp = pgd_offset_k(vaddr);
pmdp = pmd_offset(pgdp, vaddr);
if (pmd_none(*pmdp) || pmd_bad(*pmdp))
return;
ptep = pte_offset_kernel(pmdp, vaddr);
if (pte_none(*ptep) || !pte_present(*ptep))
return;
clear_page((void *)ptep);
pte_clear(&init_mm, vaddr, ptep);
}
unsigned long onchip_remap(unsigned long phys, unsigned long size, const char *name)
{
if (size < PAGE_SIZE)
size = PAGE_SIZE;
return shmedia_alloc_io(phys, size, name);
}
void onchip_unmap(unsigned long vaddr)
{
struct resource *res;
unsigned int psz;
res = shmedia_find_resource(&shmedia_iomap, vaddr);
if (!res) {
printk(KERN_ERR "%s: Failed to free 0x%08lx\n",
__FUNCTION__, vaddr);
return;
}
psz = (res->end - res->start + (PAGE_SIZE - 1)) / PAGE_SIZE;
printk(KERN_DEBUG "unmapioaddr: %6s [%2d page%s] freed\n",
res->name, psz, psz == 1 ? " " : "s");
shmedia_free_io(res);
if ((char *)res >= (char *)xresv &&
(char *)res < (char *)&xresv[XNRES]) {
xres_free((struct xresource *)res);
} else {
kfree(res);
}
}
#ifdef CONFIG_PROC_FS
static int
ioremap_proc_info(char *buf, char **start, off_t fpos, int length, int *eof,
void *data)
{
char *p = buf, *e = buf + length;
struct resource *r;
const char *nm;
for (r = ((struct resource *)data)->child; r != NULL; r = r->sibling) {
if (p + 32 >= e) /* Better than nothing */
break;
if ((nm = r->name) == 0) nm = "???";
p += sprintf(p, "%08lx-%08lx: %s\n", r->start, r->end, nm);
}
return p-buf;
}
#endif /* CONFIG_PROC_FS */
static int __init register_proc_onchip(void)
{
#ifdef CONFIG_PROC_FS
create_proc_read_entry("io_map",0,0, ioremap_proc_info, &shmedia_iomap);
#endif
return 0;
}
__initcall(register_proc_onchip);