OpenCloudOS-Kernel/arch/blackfin/mm/init.c

193 lines
5.7 KiB
C

/*
* File: arch/blackfin/mm/init.c
* Based on:
* Author:
*
* Created:
* Description:
*
* Modified:
* Copyright 2004-2007 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that 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, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/swap.h>
#include <linux/bootmem.h>
#include <linux/uaccess.h>
#include <asm/bfin-global.h>
#include <asm/l1layout.h>
#include "blackfin_sram.h"
/*
* BAD_PAGE is the page that is used for page faults when linux
* is out-of-memory. Older versions of linux just did a
* do_exit(), but using this instead means there is less risk
* for a process dying in kernel mode, possibly leaving a inode
* unused etc..
*
* BAD_PAGETABLE is the accompanying page-table: it is initialized
* to point to BAD_PAGE entries.
*
* ZERO_PAGE is a special page that is used for zero-initialized
* data and COW.
*/
static unsigned long empty_bad_page_table;
static unsigned long empty_bad_page;
unsigned long empty_zero_page;
/*
* paging_init() continues the virtual memory environment setup which
* was begun by the code in arch/head.S.
* The parameters are pointers to where to stick the starting and ending
* addresses of available kernel virtual memory.
*/
void __init paging_init(void)
{
/*
* make sure start_mem is page aligned, otherwise bootmem and
* page_alloc get different views og the world
*/
unsigned long end_mem = memory_end & PAGE_MASK;
pr_debug("start_mem is %#lx virtual_end is %#lx\n", PAGE_ALIGN(memory_start), end_mem);
/*
* initialize the bad page table and bad page to point
* to a couple of allocated pages
*/
empty_bad_page_table = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
empty_bad_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
empty_zero_page = (unsigned long)alloc_bootmem_pages(PAGE_SIZE);
memset((void *)empty_zero_page, 0, PAGE_SIZE);
/*
* Set up SFC/DFC registers (user data space)
*/
set_fs(KERNEL_DS);
pr_debug("free_area_init -> start_mem is %#lx virtual_end is %#lx\n",
PAGE_ALIGN(memory_start), end_mem);
{
unsigned long zones_size[MAX_NR_ZONES] = { 0, };
zones_size[ZONE_DMA] = (end_mem - PAGE_OFFSET) >> PAGE_SHIFT;
zones_size[ZONE_NORMAL] = 0;
#ifdef CONFIG_HIGHMEM
zones_size[ZONE_HIGHMEM] = 0;
#endif
free_area_init(zones_size);
}
}
void __init mem_init(void)
{
unsigned int codek = 0, datak = 0, initk = 0;
unsigned int reservedpages = 0, freepages = 0;
unsigned long tmp;
unsigned long start_mem = memory_start;
unsigned long end_mem = memory_end;
end_mem &= PAGE_MASK;
high_memory = (void *)end_mem;
start_mem = PAGE_ALIGN(start_mem);
max_mapnr = num_physpages = MAP_NR(high_memory);
printk(KERN_DEBUG "Kernel managed physical pages: %lu\n", num_physpages);
/* This will put all memory onto the freelists. */
totalram_pages = free_all_bootmem();
reservedpages = 0;
for (tmp = 0; tmp < max_mapnr; tmp++)
if (PageReserved(pfn_to_page(tmp)))
reservedpages++;
freepages = max_mapnr - reservedpages;
/* do not count in kernel image between _rambase and _ramstart */
reservedpages -= (_ramstart - _rambase) >> PAGE_SHIFT;
#if (defined(CONFIG_BFIN_ICACHE) && ANOMALY_05000263)
reservedpages += (_ramend - memory_end - DMA_UNCACHED_REGION) >> PAGE_SHIFT;
#endif
codek = (_etext - _stext) >> 10;
initk = (__init_end - __init_begin) >> 10;
datak = ((_ramstart - _rambase) >> 10) - codek - initk;
printk(KERN_INFO
"Memory available: %luk/%luk RAM, "
"(%uk init code, %uk kernel code, %uk data, %uk dma, %uk reserved)\n",
(unsigned long) freepages << (PAGE_SHIFT-10), _ramend >> 10,
initk, codek, datak, DMA_UNCACHED_REGION >> 10, (reservedpages << (PAGE_SHIFT-10)));
}
static int __init sram_init(void)
{
unsigned long tmp;
/* Initialize the blackfin L1 Memory. */
bfin_sram_init();
/* Allocate this once; never free it. We assume this gives us a
pointer to the start of L1 scratchpad memory; panic if it
doesn't. */
tmp = (unsigned long)l1sram_alloc(sizeof(struct l1_scratch_task_info));
if (tmp != (unsigned long)L1_SCRATCH_TASK_INFO) {
printk(KERN_EMERG "mem_init(): Did not get the right address from l1sram_alloc: %08lx != %08lx\n",
tmp, (unsigned long)L1_SCRATCH_TASK_INFO);
panic("No L1, time to give up\n");
}
return 0;
}
pure_initcall(sram_init);
static void __init free_init_pages(const char *what, unsigned long begin, unsigned long end)
{
unsigned long addr;
/* next to check that the page we free is not a partial page */
for (addr = begin; addr + PAGE_SIZE <= end; addr += PAGE_SIZE) {
ClearPageReserved(virt_to_page(addr));
init_page_count(virt_to_page(addr));
free_page(addr);
totalram_pages++;
}
printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
}
#ifdef CONFIG_BLK_DEV_INITRD
void __init free_initrd_mem(unsigned long start, unsigned long end)
{
#ifndef CONFIG_MPU
free_init_pages("initrd memory", start, end);
#endif
}
#endif
void __init_refok free_initmem(void)
{
#if defined CONFIG_RAMKERNEL && !defined CONFIG_MPU
free_init_pages("unused kernel memory",
(unsigned long)(&__init_begin),
(unsigned long)(&__init_end));
#endif
}