307 lines
7.3 KiB
C
307 lines
7.3 KiB
C
/*
|
|
* linux/arch/m68k/mm/motorola.c
|
|
*
|
|
* Routines specific to the Motorola MMU, originally from:
|
|
* linux/arch/m68k/init.c
|
|
* which are Copyright (C) 1995 Hamish Macdonald
|
|
*
|
|
* Moved 8/20/1999 Sam Creasey
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/signal.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/string.h>
|
|
#include <linux/types.h>
|
|
#include <linux/init.h>
|
|
#include <linux/bootmem.h>
|
|
#include <linux/gfp.h>
|
|
|
|
#include <asm/setup.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/page.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/machdep.h>
|
|
#include <asm/io.h>
|
|
#include <asm/dma.h>
|
|
#ifdef CONFIG_ATARI
|
|
#include <asm/atari_stram.h>
|
|
#endif
|
|
#include <asm/sections.h>
|
|
|
|
#undef DEBUG
|
|
|
|
#ifndef mm_cachebits
|
|
/*
|
|
* Bits to add to page descriptors for "normal" caching mode.
|
|
* For 68020/030 this is 0.
|
|
* For 68040, this is _PAGE_CACHE040 (cachable, copyback)
|
|
*/
|
|
unsigned long mm_cachebits;
|
|
EXPORT_SYMBOL(mm_cachebits);
|
|
#endif
|
|
|
|
/* size of memory already mapped in head.S */
|
|
#define INIT_MAPPED_SIZE (4UL<<20)
|
|
|
|
extern unsigned long availmem;
|
|
|
|
static pte_t * __init kernel_page_table(void)
|
|
{
|
|
pte_t *ptablep;
|
|
|
|
ptablep = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
|
|
|
|
clear_page(ptablep);
|
|
__flush_page_to_ram(ptablep);
|
|
flush_tlb_kernel_page(ptablep);
|
|
nocache_page(ptablep);
|
|
|
|
return ptablep;
|
|
}
|
|
|
|
static pmd_t *last_pgtable __initdata = NULL;
|
|
pmd_t *zero_pgtable __initdata = NULL;
|
|
|
|
static pmd_t * __init kernel_ptr_table(void)
|
|
{
|
|
if (!last_pgtable) {
|
|
unsigned long pmd, last;
|
|
int i;
|
|
|
|
/* Find the last ptr table that was used in head.S and
|
|
* reuse the remaining space in that page for further
|
|
* ptr tables.
|
|
*/
|
|
last = (unsigned long)kernel_pg_dir;
|
|
for (i = 0; i < PTRS_PER_PGD; i++) {
|
|
if (!pgd_present(kernel_pg_dir[i]))
|
|
continue;
|
|
pmd = __pgd_page(kernel_pg_dir[i]);
|
|
if (pmd > last)
|
|
last = pmd;
|
|
}
|
|
|
|
last_pgtable = (pmd_t *)last;
|
|
#ifdef DEBUG
|
|
printk("kernel_ptr_init: %p\n", last_pgtable);
|
|
#endif
|
|
}
|
|
|
|
last_pgtable += PTRS_PER_PMD;
|
|
if (((unsigned long)last_pgtable & ~PAGE_MASK) == 0) {
|
|
last_pgtable = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
|
|
|
|
clear_page(last_pgtable);
|
|
__flush_page_to_ram(last_pgtable);
|
|
flush_tlb_kernel_page(last_pgtable);
|
|
nocache_page(last_pgtable);
|
|
}
|
|
|
|
return last_pgtable;
|
|
}
|
|
|
|
static void __init map_node(int node)
|
|
{
|
|
#define PTRTREESIZE (256*1024)
|
|
#define ROOTTREESIZE (32*1024*1024)
|
|
unsigned long physaddr, virtaddr, size;
|
|
pgd_t *pgd_dir;
|
|
pmd_t *pmd_dir;
|
|
pte_t *pte_dir;
|
|
|
|
size = m68k_memory[node].size;
|
|
physaddr = m68k_memory[node].addr;
|
|
virtaddr = (unsigned long)phys_to_virt(physaddr);
|
|
physaddr |= m68k_supervisor_cachemode |
|
|
_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY;
|
|
if (CPU_IS_040_OR_060)
|
|
physaddr |= _PAGE_GLOBAL040;
|
|
|
|
while (size > 0) {
|
|
#ifdef DEBUG
|
|
if (!(virtaddr & (PTRTREESIZE-1)))
|
|
printk ("\npa=%#lx va=%#lx ", physaddr & PAGE_MASK,
|
|
virtaddr);
|
|
#endif
|
|
pgd_dir = pgd_offset_k(virtaddr);
|
|
if (virtaddr && CPU_IS_020_OR_030) {
|
|
if (!(virtaddr & (ROOTTREESIZE-1)) &&
|
|
size >= ROOTTREESIZE) {
|
|
#ifdef DEBUG
|
|
printk ("[very early term]");
|
|
#endif
|
|
pgd_val(*pgd_dir) = physaddr;
|
|
size -= ROOTTREESIZE;
|
|
virtaddr += ROOTTREESIZE;
|
|
physaddr += ROOTTREESIZE;
|
|
continue;
|
|
}
|
|
}
|
|
if (!pgd_present(*pgd_dir)) {
|
|
pmd_dir = kernel_ptr_table();
|
|
#ifdef DEBUG
|
|
printk ("[new pointer %p]", pmd_dir);
|
|
#endif
|
|
pgd_set(pgd_dir, pmd_dir);
|
|
} else
|
|
pmd_dir = pmd_offset(pgd_dir, virtaddr);
|
|
|
|
if (CPU_IS_020_OR_030) {
|
|
if (virtaddr) {
|
|
#ifdef DEBUG
|
|
printk ("[early term]");
|
|
#endif
|
|
pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr;
|
|
physaddr += PTRTREESIZE;
|
|
} else {
|
|
int i;
|
|
#ifdef DEBUG
|
|
printk ("[zero map]");
|
|
#endif
|
|
zero_pgtable = kernel_ptr_table();
|
|
pte_dir = (pte_t *)zero_pgtable;
|
|
pmd_dir->pmd[0] = virt_to_phys(pte_dir) |
|
|
_PAGE_TABLE | _PAGE_ACCESSED;
|
|
pte_val(*pte_dir++) = 0;
|
|
physaddr += PAGE_SIZE;
|
|
for (i = 1; i < 64; physaddr += PAGE_SIZE, i++)
|
|
pte_val(*pte_dir++) = physaddr;
|
|
}
|
|
size -= PTRTREESIZE;
|
|
virtaddr += PTRTREESIZE;
|
|
} else {
|
|
if (!pmd_present(*pmd_dir)) {
|
|
#ifdef DEBUG
|
|
printk ("[new table]");
|
|
#endif
|
|
pte_dir = kernel_page_table();
|
|
pmd_set(pmd_dir, pte_dir);
|
|
}
|
|
pte_dir = pte_offset_kernel(pmd_dir, virtaddr);
|
|
|
|
if (virtaddr) {
|
|
if (!pte_present(*pte_dir))
|
|
pte_val(*pte_dir) = physaddr;
|
|
} else
|
|
pte_val(*pte_dir) = 0;
|
|
size -= PAGE_SIZE;
|
|
virtaddr += PAGE_SIZE;
|
|
physaddr += PAGE_SIZE;
|
|
}
|
|
|
|
}
|
|
#ifdef DEBUG
|
|
printk("\n");
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* paging_init() continues the virtual memory environment setup which
|
|
* was begun by the code in arch/head.S.
|
|
*/
|
|
void __init paging_init(void)
|
|
{
|
|
unsigned long zones_size[MAX_NR_ZONES] = { 0, };
|
|
unsigned long min_addr, max_addr;
|
|
unsigned long addr, size, end;
|
|
int i;
|
|
|
|
#ifdef DEBUG
|
|
printk ("start of paging_init (%p, %lx)\n", kernel_pg_dir, availmem);
|
|
#endif
|
|
|
|
/* Fix the cache mode in the page descriptors for the 680[46]0. */
|
|
if (CPU_IS_040_OR_060) {
|
|
int i;
|
|
#ifndef mm_cachebits
|
|
mm_cachebits = _PAGE_CACHE040;
|
|
#endif
|
|
for (i = 0; i < 16; i++)
|
|
pgprot_val(protection_map[i]) |= _PAGE_CACHE040;
|
|
}
|
|
|
|
min_addr = m68k_memory[0].addr;
|
|
max_addr = min_addr + m68k_memory[0].size;
|
|
for (i = 1; i < m68k_num_memory;) {
|
|
if (m68k_memory[i].addr < min_addr) {
|
|
printk("Ignoring memory chunk at 0x%lx:0x%lx before the first chunk\n",
|
|
m68k_memory[i].addr, m68k_memory[i].size);
|
|
printk("Fix your bootloader or use a memfile to make use of this area!\n");
|
|
m68k_num_memory--;
|
|
memmove(m68k_memory + i, m68k_memory + i + 1,
|
|
(m68k_num_memory - i) * sizeof(struct m68k_mem_info));
|
|
continue;
|
|
}
|
|
addr = m68k_memory[i].addr + m68k_memory[i].size;
|
|
if (addr > max_addr)
|
|
max_addr = addr;
|
|
i++;
|
|
}
|
|
m68k_memoffset = min_addr - PAGE_OFFSET;
|
|
m68k_virt_to_node_shift = fls(max_addr - min_addr - 1) - 6;
|
|
|
|
module_fixup(NULL, __start_fixup, __stop_fixup);
|
|
flush_icache();
|
|
|
|
high_memory = phys_to_virt(max_addr);
|
|
|
|
min_low_pfn = availmem >> PAGE_SHIFT;
|
|
max_low_pfn = max_addr >> PAGE_SHIFT;
|
|
|
|
for (i = 0; i < m68k_num_memory; i++) {
|
|
addr = m68k_memory[i].addr;
|
|
end = addr + m68k_memory[i].size;
|
|
m68k_setup_node(i);
|
|
availmem = PAGE_ALIGN(availmem);
|
|
availmem += init_bootmem_node(NODE_DATA(i),
|
|
availmem >> PAGE_SHIFT,
|
|
addr >> PAGE_SHIFT,
|
|
end >> PAGE_SHIFT);
|
|
}
|
|
|
|
/*
|
|
* Map the physical memory available into the kernel virtual
|
|
* address space. First initialize the bootmem allocator with
|
|
* the memory we already mapped, so map_node() has something
|
|
* to allocate.
|
|
*/
|
|
addr = m68k_memory[0].addr;
|
|
size = m68k_memory[0].size;
|
|
free_bootmem_node(NODE_DATA(0), availmem, min(INIT_MAPPED_SIZE, size) - (availmem - addr));
|
|
map_node(0);
|
|
if (size > INIT_MAPPED_SIZE)
|
|
free_bootmem_node(NODE_DATA(0), addr + INIT_MAPPED_SIZE, size - INIT_MAPPED_SIZE);
|
|
|
|
for (i = 1; i < m68k_num_memory; i++)
|
|
map_node(i);
|
|
|
|
flush_tlb_all();
|
|
|
|
/*
|
|
* initialize the bad page table and bad page to point
|
|
* to a couple of allocated pages
|
|
*/
|
|
empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
|
|
|
|
/*
|
|
* Set up SFC/DFC registers
|
|
*/
|
|
set_fs(KERNEL_DS);
|
|
|
|
#ifdef DEBUG
|
|
printk ("before free_area_init\n");
|
|
#endif
|
|
for (i = 0; i < m68k_num_memory; i++) {
|
|
zones_size[ZONE_DMA] = m68k_memory[i].size >> PAGE_SHIFT;
|
|
free_area_init_node(i, zones_size,
|
|
m68k_memory[i].addr >> PAGE_SHIFT, NULL);
|
|
if (node_present_pages(i))
|
|
node_set_state(i, N_NORMAL_MEMORY);
|
|
}
|
|
}
|
|
|