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/*
* Carsten Langgaard, carstenl@mips.com
* Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
*
* ########################################################################
*
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* ########################################################################
*
* PROM library functions for acquiring/using memory descriptors given to
* us from the YAMON.
*
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/bootmem.h>
#include <asm/bootinfo.h>
#include <asm/page.h>
#include <asm/mips-boards/prom.h>
/*#define DEBUG*/
enum yamon_memtypes {
yamon_dontuse,
yamon_prom,
yamon_free,
};
struct prom_pmemblock mdesc[PROM_MAX_PMEMBLOCKS];
#define MEMTYPE_DONTUSE 0
#define MEMTYPE_PROM 1
#define MEMTYPE_FREE 2
#ifdef DEBUG
static char *mtypes[3] = {
"Dont use memory",
"YAMON PROM memory",
"Free memmory",
};
#endif
/* References to section boundaries */
extern char _end;
#define PFN_ALIGN(x) (((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK)
struct prom_pmemblock * __init prom_getmdesc(void)
{
char *memsize_str;
unsigned int memsize;
memsize_str = prom_getenv("memsize");
if (!memsize_str) {
prom_printf("memsize not set in boot prom, set to default (32Mb)\n");
memsize = 0x02000000;
} else {
#ifdef DEBUG
prom_printf("prom_memsize = %s\n", memsize_str);
#endif
memsize = simple_strtol(memsize_str, NULL, 0);
}
memset(mdesc, 0, sizeof(mdesc));
mdesc[0].type = yamon_dontuse;
mdesc[0].base = 0x00000000;
mdesc[0].size = 0x00001000;
mdesc[1].type = yamon_prom;
mdesc[1].base = 0x00001000;
mdesc[1].size = 0x000ef000;
#if (CONFIG_MIPS_MALTA)
/*
* The area 0x000f0000-0x000fffff is allocated for BIOS memory by the
* south bridge and PCI access always forwarded to the ISA Bus and
* BIOSCS# is always generated.
* This mean that this area can't be used as DMA memory for PCI
* devices.
*/
mdesc[2].type = yamon_dontuse;
mdesc[2].base = 0x000f0000;
mdesc[2].size = 0x00010000;
#else
mdesc[2].type = yamon_prom;
mdesc[2].base = 0x000f0000;
mdesc[2].size = 0x00010000;
#endif
mdesc[3].type = yamon_dontuse;
mdesc[3].base = 0x00100000;
mdesc[3].size = CPHYSADDR(PFN_ALIGN(&_end)) - mdesc[3].base;
mdesc[4].type = yamon_free;
mdesc[4].base = CPHYSADDR(PFN_ALIGN(&_end));
mdesc[4].size = memsize - mdesc[4].base;
return &mdesc[0];
}
int __init page_is_ram(unsigned long pagenr)
{
if ((pagenr << PAGE_SHIFT) < mdesc[4].base + mdesc[4].size)
return 1;
return 0;
}
static struct prom_pmemblock pblocks[PROM_MAX_PMEMBLOCKS];
static int __init prom_memtype_classify (unsigned int type)
{
switch (type) {
case yamon_free:
return MEMTYPE_FREE;
case yamon_prom:
return MEMTYPE_PROM;
default:
return MEMTYPE_DONTUSE;
}
}
static inline unsigned long find_max_low_pfn(void)
{
struct prom_pmemblock *p, *highest;
unsigned long pfn;
p = pblocks;
highest = 0;
while (p->size != 0) {
if (!highest || p->base > highest->base)
highest = p;
p++;
}
pfn = (highest->base + highest->size) >> PAGE_SHIFT;
#ifdef DEBUG
prom_printf("find_max_low_pfn: 0x%lx pfns.\n", pfn);
#endif
return pfn;
}
static inline struct prom_pmemblock *find_largest_memblock(void)
{
struct prom_pmemblock *p, *largest;
p = pblocks;
largest = 0;
while (p->size != 0) {
if (!largest || p->size > largest->size)
largest = p;
p++;
}
return largest;
}
void __init prom_meminit(void)
{
struct prom_pmemblock *largest, *p;
unsigned long bootmap_size;
int totram;
int i = 0;
#ifdef DEBUG
prom_printf("YAMON MEMORY DESCRIPTOR dump:\n");
p = prom_getmdesc();
while (p->size) {
prom_printf("[%d,%p]: base<%08lx> size<%08lx> type<%s>\n",
i, p, p->base, p->size, mtypes[p->type]);
p++;
i++;
}
#endif
totram = 0;
i = 0;
p = prom_getmdesc();
while (p->size) {
pblocks[i].type = prom_memtype_classify (p->type);
pblocks[i].base = p->base;
pblocks[i].size = p->size;
switch (pblocks[i].type) {
case MEMTYPE_FREE:
totram += pblocks[i].size;
#ifdef DEBUG
prom_printf("free_chunk[%d]: base=%08lx size=%d\n",
i, pblocks[i].base, pblocks[i].size);
#endif
i++;
break;
case MEMTYPE_PROM:
#ifdef DEBUG
prom_printf("prom_chunk[%d]: base=%08lx size=%d\n",
i, pblocks[i].base, pblocks[i].size);
#endif
i++;
break;
default:
break;
}
p++;
}
pblocks[i].base = 0xdeadbeef;
pblocks[i].size = 0; /* indicates last elem. of array */
max_low_pfn = find_max_low_pfn();
largest = find_largest_memblock();
bootmap_size = init_bootmem(largest->base >> PAGE_SHIFT, max_low_pfn);
for (i = 0; pblocks[i].size; i++)
if (pblocks[i].type == MEMTYPE_FREE)
free_bootmem(pblocks[i].base, pblocks[i].size);
/* This test is simpleminded. It will fail if the bootmem bitmap
falls into multiple adjacent PROM memory areas. */
if (bootmap_size > largest->size) {
prom_printf("CRITIAL: overwriting PROM data.\n");
BUG();
}
/* Reserve the memory bootmap itself */
reserve_bootmem(largest->base, bootmap_size);
printk("PROMLIB: Total free ram %d bytes (%dK,%dMB)\n",
totram, (totram/1024), (totram/1024/1024));
}
void prom_free_prom_memory (void)
{
struct prom_pmemblock *p;
unsigned long freed = 0;
unsigned long addr;
for (p = pblocks; p->size != 0; p++) {
if (p->type != MEMTYPE_PROM)
continue;
addr = p->base;
while (addr < p->base + p->size) {
ClearPageReserved(virt_to_page(__va(addr)));
set_page_count(virt_to_page(__va(addr)), 1);
free_page(__va(addr));
addr += PAGE_SIZE;
freed += PAGE_SIZE;
}
}
printk("Freeing prom memory: %ldkb freed\n", freed >> 10);
}
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