mirror of
git://projects.qi-hardware.com/openwrt-xburst.git
synced 2024-11-09 21:41:53 +02:00
12a0868f92
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@24087 3c298f89-4303-0410-b956-a3cf2f4a3e73
318 lines
7.9 KiB
C
318 lines
7.9 KiB
C
/*
|
|
* linux/arch/m68k/mm/cf-mmu.c
|
|
*
|
|
* Based upon linux/arch/m68k/mm/sun3mmu.c
|
|
* Based upon linux/arch/ppc/mm/mmu_context.c
|
|
*
|
|
* Implementations of mm routines specific to the Coldfire MMU.
|
|
*
|
|
* Copyright (c) 2008 Freescale Semiconductor, Inc.
|
|
* Copyright Freescale Semiconductor, Inc. 2008-2009
|
|
* Jason Jin Jason.Jin@freescale.com
|
|
* Shrek Wu B16972@freescale.com
|
|
*/
|
|
|
|
#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>
|
|
#ifdef CONFIG_BLK_DEV_RAM
|
|
#include <linux/blkdev.h>
|
|
#endif
|
|
#include <linux/bootmem.h>
|
|
|
|
#include <asm/setup.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm/page.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/system.h>
|
|
#include <asm/machdep.h>
|
|
#include <asm/io.h>
|
|
#include <asm/mmu_context.h>
|
|
#include <asm/cf_pgalloc.h>
|
|
|
|
#include <asm/coldfire.h>
|
|
#include <asm/tlbflush.h>
|
|
|
|
#define KMAPAREA(x) ((x >= VMALLOC_START) && (x < KMAP_END))
|
|
|
|
#undef DEBUG
|
|
|
|
#ifdef CONFIG_VDSO
|
|
unsigned long next_mmu_context;
|
|
#else
|
|
mm_context_t next_mmu_context;
|
|
#endif
|
|
|
|
unsigned long context_map[LAST_CONTEXT / BITS_PER_LONG + 1];
|
|
|
|
atomic_t nr_free_contexts;
|
|
struct mm_struct *context_mm[LAST_CONTEXT+1];
|
|
void steal_context(void);
|
|
#ifdef CONFIG_M5445X
|
|
void m68k_setup_node(int);
|
|
#endif
|
|
const char bad_pmd_string[] = "Bad pmd in pte_alloc: %08lx\n";
|
|
|
|
extern unsigned long empty_bad_page_table;
|
|
extern unsigned long empty_bad_page;
|
|
extern unsigned long num_pages;
|
|
#ifdef CONFIG_M5445X
|
|
extern unsigned long availmem;
|
|
#endif
|
|
extern char __init_begin, __init_end;
|
|
|
|
/*
|
|
* Free memory used for system initialization.
|
|
*/
|
|
void free_initmem(void)
|
|
{
|
|
#if 0
|
|
unsigned long addr;
|
|
unsigned long start = (unsigned long)&__init_begin;
|
|
unsigned long end = (unsigned long)&__init_end;
|
|
|
|
printk(KERN_INFO "free_initmem: __init_begin = 0x%lx __init_end = 0x%lx\n", start, end);
|
|
|
|
addr = (unsigned long)&__init_begin;
|
|
for (; addr < (unsigned long)&__init_end; addr += PAGE_SIZE) {
|
|
/* not currently used */
|
|
virt_to_page(addr)->flags &= ~(1 << PG_reserved);
|
|
init_page_count(virt_to_page(addr));
|
|
free_page(addr);
|
|
totalram_pages++;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Initialize the paging system.
|
|
*/
|
|
void __init paging_init(void)
|
|
{
|
|
pgd_t * pg_dir;
|
|
pte_t * pg_table;
|
|
int i;
|
|
unsigned long address;
|
|
unsigned long next_pgtable;
|
|
unsigned long zones_size[MAX_NR_ZONES];
|
|
unsigned long size;
|
|
enum zone_type zone;
|
|
|
|
/* allocate zero page */
|
|
empty_zero_page = (void *)alloc_bootmem_pages(PAGE_SIZE);
|
|
memset((void *)empty_zero_page, 0, PAGE_SIZE);
|
|
|
|
/* zero kernel page directory */
|
|
pg_dir = swapper_pg_dir;
|
|
memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
|
|
/*
|
|
* setup page tables for PHYSRAM
|
|
*/
|
|
|
|
/* starting loc in page directory */
|
|
pg_dir += PAGE_OFFSET >> PGDIR_SHIFT;
|
|
|
|
/* allocate page tables */
|
|
size = num_pages * sizeof(pte_t);
|
|
size = (size + PAGE_SIZE) & ~(PAGE_SIZE-1);
|
|
next_pgtable = (unsigned long)alloc_bootmem_pages(size);
|
|
address = PAGE_OFFSET;
|
|
while (address < (unsigned long)high_memory) {
|
|
/* setup page table in page directory */
|
|
pg_table = (pte_t *)next_pgtable;
|
|
next_pgtable += PTRS_PER_PTE * sizeof(pte_t);
|
|
pgd_val(*pg_dir) = (unsigned long)pg_table;
|
|
pg_dir++;
|
|
|
|
/* create PTEs in page table */
|
|
for (i=0; i<PTRS_PER_PTE; ++i, ++pg_table) {
|
|
pte_t pte = pfn_pte(virt_to_pfn(address), PAGE_INIT);
|
|
if (address >= (unsigned long)high_memory)
|
|
pte_val (pte) = 0;
|
|
|
|
set_pte(pg_table, pte);
|
|
address += PAGE_SIZE;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* setup page tables for DMA area
|
|
*/
|
|
|
|
/* starting loc in page directory */
|
|
pg_dir = swapper_pg_dir;
|
|
pg_dir += CONFIG_DMA_BASE >> PGDIR_SHIFT;
|
|
|
|
/* allocate page tables */
|
|
size = (CONFIG_DMA_SIZE >> PAGE_SHIFT) * sizeof(pte_t);
|
|
size = (size + PAGE_SIZE) & ~(PAGE_SIZE-1);
|
|
next_pgtable = (unsigned long)alloc_bootmem_pages(size);
|
|
address = CONFIG_DMA_BASE;
|
|
while (address < (CONFIG_DMA_BASE + CONFIG_DMA_SIZE)) {
|
|
/* setup page table in page directory */
|
|
pg_table = (pte_t *)next_pgtable;
|
|
next_pgtable += PTRS_PER_PTE * sizeof(pte_t);
|
|
pgd_val(*pg_dir) = (unsigned long)pg_table;
|
|
pg_dir++;
|
|
|
|
/* create PTEs in page table */
|
|
for (i=0; i<PTRS_PER_PTE; ++i, ++pg_table) {
|
|
pte_t pte = pfn_pte(virt_to_pfn(address), PAGE_INIT);
|
|
if (address >= (CONFIG_DMA_BASE + CONFIG_DMA_SIZE))
|
|
pte_val (pte) = 0;
|
|
|
|
set_pte(pg_table, pte);
|
|
address += PAGE_SIZE;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* setup zones
|
|
*/
|
|
|
|
current->mm = NULL;
|
|
|
|
/* clear zones */
|
|
for (zone = 0; zone < MAX_NR_ZONES; zone++)
|
|
zones_size[zone] = 0x0;
|
|
|
|
zones_size[ZONE_DMA] = CONFIG_DMA_SIZE >> PAGE_SHIFT;
|
|
zones_size[ZONE_NORMAL] = (((unsigned long)high_memory -
|
|
PAGE_OFFSET) >> PAGE_SHIFT) -
|
|
zones_size[ZONE_DMA];
|
|
|
|
free_area_init(zones_size);
|
|
}
|
|
/*
|
|
* Handle a missed TLB
|
|
*/
|
|
int cf_tlb_miss(struct pt_regs *regs, int write, int dtlb, int extension_word)
|
|
{
|
|
struct mm_struct *mm;
|
|
pgd_t *pgd;
|
|
pmd_t *pmd;
|
|
pte_t *pte;
|
|
unsigned long mmuar;
|
|
int asid;
|
|
int flags;
|
|
|
|
local_save_flags(flags);
|
|
local_irq_disable();
|
|
|
|
mmuar = ( dtlb ) ? regs->mmuar
|
|
: regs->pc + (extension_word * sizeof(long));
|
|
|
|
mm = (!user_mode(regs) && KMAPAREA(mmuar)) ? &init_mm : current->mm;
|
|
|
|
if (!mm) {
|
|
local_irq_restore(flags);
|
|
return (-1);
|
|
}
|
|
|
|
pgd = pgd_offset(mm, mmuar);
|
|
if (pgd_none(*pgd)) {
|
|
local_irq_restore(flags);
|
|
return (-1);
|
|
}
|
|
|
|
pmd = pmd_offset(pgd, mmuar);
|
|
if (pmd_none(*pmd)) {
|
|
local_irq_restore(flags);
|
|
return (-1);
|
|
}
|
|
|
|
pte = (KMAPAREA(mmuar)) ? pte_offset_kernel(pmd, mmuar)
|
|
: pte_offset_map(pmd, mmuar);
|
|
if (pte_none(*pte) || !pte_present(*pte)) {
|
|
local_irq_restore(flags);
|
|
return (-1);
|
|
}
|
|
|
|
if (write) {
|
|
if (!pte_write(*pte)) {
|
|
local_irq_restore(flags);
|
|
return (-1);
|
|
}
|
|
set_pte(pte, pte_mkdirty(*pte));
|
|
}
|
|
|
|
set_pte(pte, pte_mkyoung(*pte));
|
|
asid = cpu_context(mm) & 0xff;
|
|
if (!pte_dirty(*pte) && !KMAPAREA(mmuar))
|
|
set_pte(pte, pte_wrprotect(*pte));
|
|
|
|
*MMUTR = (mmuar & PAGE_MASK) | (asid << CF_ASID_MMU_SHIFT)
|
|
| (((int)(pte->pte) & (int)CF_PAGE_MMUTR_MASK ) >> CF_PAGE_MMUTR_SHIFT)
|
|
| MMUTR_V;
|
|
|
|
*MMUDR = (pte_val(*pte) & PAGE_MASK)
|
|
| ((pte->pte) & CF_PAGE_MMUDR_MASK)
|
|
| MMUDR_SZ8K | MMUDR_X;
|
|
|
|
if ( dtlb )
|
|
*MMUOR = MMUOR_ACC | MMUOR_UAA;
|
|
else
|
|
*MMUOR = MMUOR_ITLB | MMUOR_ACC | MMUOR_UAA;
|
|
|
|
asm("nop");
|
|
|
|
#ifdef DEBUG
|
|
printk("cf_tlb_miss: va=%lx, pa=%lx\n", (mmuar & PAGE_MASK),
|
|
(pte_val(*pte) & PAGE_MASK));
|
|
#endif
|
|
local_irq_restore(flags);
|
|
return (0);
|
|
}
|
|
|
|
|
|
/*
|
|
* Context Management
|
|
*
|
|
* Based on arch/ppc/mmu_context.c
|
|
*/
|
|
|
|
/*
|
|
* Initialize the context management system.
|
|
*/
|
|
void __init mmu_context_init(void)
|
|
{
|
|
/*
|
|
* Some processors have too few contexts to reserve one for
|
|
* init_mm, and require using context 0 for a normal task.
|
|
* Other processors reserve the use of context zero for the kernel.
|
|
* This code assumes FIRST_CONTEXT < 32.
|
|
*/
|
|
context_map[0] = (1 << FIRST_CONTEXT) - 1;
|
|
next_mmu_context = FIRST_CONTEXT;
|
|
atomic_set(&nr_free_contexts, LAST_CONTEXT - FIRST_CONTEXT + 1);
|
|
}
|
|
|
|
/*
|
|
* Steal a context from a task that has one at the moment.
|
|
* This is only used on 8xx and 4xx and we presently assume that
|
|
* they don't do SMP. If they do then thicfpgalloc.hs will have to check
|
|
* whether the MM we steal is in use.
|
|
* We also assume that this is only used on systems that don't
|
|
* use an MMU hash table - this is true for 8xx and 4xx.
|
|
* This isn't an LRU system, it just frees up each context in
|
|
* turn (sort-of pseudo-random replacement :). This would be the
|
|
* place to implement an LRU scheme if anyone was motivated to do it.
|
|
* -- paulus
|
|
*/
|
|
void steal_context(void)
|
|
{
|
|
struct mm_struct *mm;
|
|
/* free up context `next_mmu_context' */
|
|
/* if we shouldn't free context 0, don't... */
|
|
if (next_mmu_context < FIRST_CONTEXT)
|
|
next_mmu_context = FIRST_CONTEXT;
|
|
mm = context_mm[next_mmu_context];
|
|
flush_tlb_mm(mm);
|
|
destroy_context(mm);
|
|
}
|