mirror of https://gitee.com/openkylin/linux.git
474 lines
11 KiB
C
474 lines
11 KiB
C
/*
|
|
* This file contains the routines setting up the linux page tables.
|
|
* -- paulus
|
|
*
|
|
* Derived from arch/ppc/mm/init.c:
|
|
* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
|
|
*
|
|
* Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
|
|
* and Cort Dougan (PReP) (cort@cs.nmt.edu)
|
|
* Copyright (C) 1996 Paul Mackerras
|
|
* Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
|
|
*
|
|
* Derived from "arch/i386/mm/init.c"
|
|
* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
|
|
*
|
|
* 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.
|
|
*
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/vmalloc.h>
|
|
#include <linux/init.h>
|
|
#include <linux/highmem.h>
|
|
|
|
#include <asm/pgtable.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/io.h>
|
|
|
|
#include "mmu_decl.h"
|
|
|
|
unsigned long ioremap_base;
|
|
unsigned long ioremap_bot;
|
|
EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */
|
|
int io_bat_index;
|
|
|
|
#if defined(CONFIG_6xx) || defined(CONFIG_POWER3)
|
|
#define HAVE_BATS 1
|
|
#endif
|
|
|
|
#if defined(CONFIG_FSL_BOOKE)
|
|
#define HAVE_TLBCAM 1
|
|
#endif
|
|
|
|
extern char etext[], _stext[];
|
|
|
|
#ifdef CONFIG_SMP
|
|
extern void hash_page_sync(void);
|
|
#endif
|
|
|
|
#ifdef HAVE_BATS
|
|
extern unsigned long v_mapped_by_bats(unsigned long va);
|
|
extern unsigned long p_mapped_by_bats(unsigned long pa);
|
|
void setbat(int index, unsigned long virt, unsigned long phys,
|
|
unsigned int size, int flags);
|
|
|
|
#else /* !HAVE_BATS */
|
|
#define v_mapped_by_bats(x) (0UL)
|
|
#define p_mapped_by_bats(x) (0UL)
|
|
#endif /* HAVE_BATS */
|
|
|
|
#ifdef HAVE_TLBCAM
|
|
extern unsigned int tlbcam_index;
|
|
extern unsigned long v_mapped_by_tlbcam(unsigned long va);
|
|
extern unsigned long p_mapped_by_tlbcam(unsigned long pa);
|
|
#else /* !HAVE_TLBCAM */
|
|
#define v_mapped_by_tlbcam(x) (0UL)
|
|
#define p_mapped_by_tlbcam(x) (0UL)
|
|
#endif /* HAVE_TLBCAM */
|
|
|
|
#ifdef CONFIG_PTE_64BIT
|
|
/* 44x uses an 8kB pgdir because it has 8-byte Linux PTEs. */
|
|
#define PGDIR_ORDER 1
|
|
#else
|
|
#define PGDIR_ORDER 0
|
|
#endif
|
|
|
|
pgd_t *pgd_alloc(struct mm_struct *mm)
|
|
{
|
|
pgd_t *ret;
|
|
|
|
ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, PGDIR_ORDER);
|
|
return ret;
|
|
}
|
|
|
|
void pgd_free(pgd_t *pgd)
|
|
{
|
|
free_pages((unsigned long)pgd, PGDIR_ORDER);
|
|
}
|
|
|
|
pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
|
|
{
|
|
pte_t *pte;
|
|
extern int mem_init_done;
|
|
extern void *early_get_page(void);
|
|
|
|
if (mem_init_done) {
|
|
pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
|
|
} else {
|
|
pte = (pte_t *)early_get_page();
|
|
if (pte)
|
|
clear_page(pte);
|
|
}
|
|
return pte;
|
|
}
|
|
|
|
struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
|
|
{
|
|
struct page *ptepage;
|
|
|
|
#ifdef CONFIG_HIGHPTE
|
|
gfp_t flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_REPEAT;
|
|
#else
|
|
gfp_t flags = GFP_KERNEL | __GFP_REPEAT;
|
|
#endif
|
|
|
|
ptepage = alloc_pages(flags, 0);
|
|
if (ptepage)
|
|
clear_highpage(ptepage);
|
|
return ptepage;
|
|
}
|
|
|
|
void pte_free_kernel(pte_t *pte)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
hash_page_sync();
|
|
#endif
|
|
free_page((unsigned long)pte);
|
|
}
|
|
|
|
void pte_free(struct page *ptepage)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
hash_page_sync();
|
|
#endif
|
|
__free_page(ptepage);
|
|
}
|
|
|
|
#ifndef CONFIG_PHYS_64BIT
|
|
void __iomem *
|
|
ioremap(phys_addr_t addr, unsigned long size)
|
|
{
|
|
return __ioremap(addr, size, _PAGE_NO_CACHE);
|
|
}
|
|
#else /* CONFIG_PHYS_64BIT */
|
|
void __iomem *
|
|
ioremap64(unsigned long long addr, unsigned long size)
|
|
{
|
|
return __ioremap(addr, size, _PAGE_NO_CACHE);
|
|
}
|
|
EXPORT_SYMBOL(ioremap64);
|
|
|
|
void __iomem *
|
|
ioremap(phys_addr_t addr, unsigned long size)
|
|
{
|
|
phys_addr_t addr64 = fixup_bigphys_addr(addr, size);
|
|
|
|
return ioremap64(addr64, size);
|
|
}
|
|
#endif /* CONFIG_PHYS_64BIT */
|
|
EXPORT_SYMBOL(ioremap);
|
|
|
|
void __iomem *
|
|
__ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
|
|
{
|
|
unsigned long v, i;
|
|
phys_addr_t p;
|
|
int err;
|
|
|
|
/*
|
|
* Choose an address to map it to.
|
|
* Once the vmalloc system is running, we use it.
|
|
* Before then, we use space going down from ioremap_base
|
|
* (ioremap_bot records where we're up to).
|
|
*/
|
|
p = addr & PAGE_MASK;
|
|
size = PAGE_ALIGN(addr + size) - p;
|
|
|
|
/*
|
|
* If the address lies within the first 16 MB, assume it's in ISA
|
|
* memory space
|
|
*/
|
|
if (p < 16*1024*1024)
|
|
p += _ISA_MEM_BASE;
|
|
|
|
/*
|
|
* Don't allow anybody to remap normal RAM that we're using.
|
|
* mem_init() sets high_memory so only do the check after that.
|
|
*/
|
|
if (mem_init_done && (p < virt_to_phys(high_memory))) {
|
|
printk("__ioremap(): phys addr "PHYS_FMT" is RAM lr %p\n", p,
|
|
__builtin_return_address(0));
|
|
return NULL;
|
|
}
|
|
|
|
if (size == 0)
|
|
return NULL;
|
|
|
|
/*
|
|
* Is it already mapped? Perhaps overlapped by a previous
|
|
* BAT mapping. If the whole area is mapped then we're done,
|
|
* otherwise remap it since we want to keep the virt addrs for
|
|
* each request contiguous.
|
|
*
|
|
* We make the assumption here that if the bottom and top
|
|
* of the range we want are mapped then it's mapped to the
|
|
* same virt address (and this is contiguous).
|
|
* -- Cort
|
|
*/
|
|
if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ )
|
|
goto out;
|
|
|
|
if ((v = p_mapped_by_tlbcam(p)))
|
|
goto out;
|
|
|
|
if (mem_init_done) {
|
|
struct vm_struct *area;
|
|
area = get_vm_area(size, VM_IOREMAP);
|
|
if (area == 0)
|
|
return NULL;
|
|
v = (unsigned long) area->addr;
|
|
} else {
|
|
v = (ioremap_bot -= size);
|
|
}
|
|
|
|
if ((flags & _PAGE_PRESENT) == 0)
|
|
flags |= _PAGE_KERNEL;
|
|
if (flags & _PAGE_NO_CACHE)
|
|
flags |= _PAGE_GUARDED;
|
|
|
|
/*
|
|
* Should check if it is a candidate for a BAT mapping
|
|
*/
|
|
|
|
err = 0;
|
|
for (i = 0; i < size && err == 0; i += PAGE_SIZE)
|
|
err = map_page(v+i, p+i, flags);
|
|
if (err) {
|
|
if (mem_init_done)
|
|
vunmap((void *)v);
|
|
return NULL;
|
|
}
|
|
|
|
out:
|
|
return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
|
|
}
|
|
EXPORT_SYMBOL(__ioremap);
|
|
|
|
void iounmap(volatile void __iomem *addr)
|
|
{
|
|
/*
|
|
* If mapped by BATs then there is nothing to do.
|
|
* Calling vfree() generates a benign warning.
|
|
*/
|
|
if (v_mapped_by_bats((unsigned long)addr)) return;
|
|
|
|
if (addr > high_memory && (unsigned long) addr < ioremap_bot)
|
|
vunmap((void *) (PAGE_MASK & (unsigned long)addr));
|
|
}
|
|
EXPORT_SYMBOL(iounmap);
|
|
|
|
void __iomem *ioport_map(unsigned long port, unsigned int len)
|
|
{
|
|
return (void __iomem *) (port + _IO_BASE);
|
|
}
|
|
|
|
void ioport_unmap(void __iomem *addr)
|
|
{
|
|
/* Nothing to do */
|
|
}
|
|
EXPORT_SYMBOL(ioport_map);
|
|
EXPORT_SYMBOL(ioport_unmap);
|
|
|
|
int
|
|
map_page(unsigned long va, phys_addr_t pa, int flags)
|
|
{
|
|
pmd_t *pd;
|
|
pte_t *pg;
|
|
int err = -ENOMEM;
|
|
|
|
/* Use upper 10 bits of VA to index the first level map */
|
|
pd = pmd_offset(pgd_offset_k(va), va);
|
|
/* Use middle 10 bits of VA to index the second-level map */
|
|
pg = pte_alloc_kernel(pd, va);
|
|
if (pg != 0) {
|
|
err = 0;
|
|
set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, __pgprot(flags)));
|
|
if (mem_init_done)
|
|
flush_HPTE(0, va, pmd_val(*pd));
|
|
}
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Map in all of physical memory starting at KERNELBASE.
|
|
*/
|
|
void __init mapin_ram(void)
|
|
{
|
|
unsigned long v, p, s, f;
|
|
|
|
s = mmu_mapin_ram();
|
|
v = KERNELBASE + s;
|
|
p = PPC_MEMSTART + s;
|
|
for (; s < total_lowmem; s += PAGE_SIZE) {
|
|
if ((char *) v >= _stext && (char *) v < etext)
|
|
f = _PAGE_RAM_TEXT;
|
|
else
|
|
f = _PAGE_RAM;
|
|
map_page(v, p, f);
|
|
v += PAGE_SIZE;
|
|
p += PAGE_SIZE;
|
|
}
|
|
}
|
|
|
|
/* is x a power of 2? */
|
|
#define is_power_of_2(x) ((x) != 0 && (((x) & ((x) - 1)) == 0))
|
|
|
|
/* is x a power of 4? */
|
|
#define is_power_of_4(x) ((x) != 0 && (((x) & (x-1)) == 0) && (ffs(x) & 1))
|
|
|
|
/*
|
|
* Set up a mapping for a block of I/O.
|
|
* virt, phys, size must all be page-aligned.
|
|
* This should only be called before ioremap is called.
|
|
*/
|
|
void __init io_block_mapping(unsigned long virt, phys_addr_t phys,
|
|
unsigned int size, int flags)
|
|
{
|
|
int i;
|
|
|
|
if (virt > KERNELBASE && virt < ioremap_bot)
|
|
ioremap_bot = ioremap_base = virt;
|
|
|
|
#ifdef HAVE_BATS
|
|
/*
|
|
* Use a BAT for this if possible...
|
|
*/
|
|
if (io_bat_index < 2 && is_power_of_2(size)
|
|
&& (virt & (size - 1)) == 0 && (phys & (size - 1)) == 0) {
|
|
setbat(io_bat_index, virt, phys, size, flags);
|
|
++io_bat_index;
|
|
return;
|
|
}
|
|
#endif /* HAVE_BATS */
|
|
|
|
#ifdef HAVE_TLBCAM
|
|
/*
|
|
* Use a CAM for this if possible...
|
|
*/
|
|
if (tlbcam_index < num_tlbcam_entries && is_power_of_4(size)
|
|
&& (virt & (size - 1)) == 0 && (phys & (size - 1)) == 0) {
|
|
settlbcam(tlbcam_index, virt, phys, size, flags, 0);
|
|
++tlbcam_index;
|
|
return;
|
|
}
|
|
#endif /* HAVE_TLBCAM */
|
|
|
|
/* No BATs available, put it in the page tables. */
|
|
for (i = 0; i < size; i += PAGE_SIZE)
|
|
map_page(virt + i, phys + i, flags);
|
|
}
|
|
|
|
/* Scan the real Linux page tables and return a PTE pointer for
|
|
* a virtual address in a context.
|
|
* Returns true (1) if PTE was found, zero otherwise. The pointer to
|
|
* the PTE pointer is unmodified if PTE is not found.
|
|
*/
|
|
int
|
|
get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp)
|
|
{
|
|
pgd_t *pgd;
|
|
pmd_t *pmd;
|
|
pte_t *pte;
|
|
int retval = 0;
|
|
|
|
pgd = pgd_offset(mm, addr & PAGE_MASK);
|
|
if (pgd) {
|
|
pmd = pmd_offset(pgd, addr & PAGE_MASK);
|
|
if (pmd_present(*pmd)) {
|
|
pte = pte_offset_map(pmd, addr & PAGE_MASK);
|
|
if (pte) {
|
|
retval = 1;
|
|
*ptep = pte;
|
|
if (pmdp)
|
|
*pmdp = pmd;
|
|
/* XXX caller needs to do pte_unmap, yuck */
|
|
}
|
|
}
|
|
}
|
|
return(retval);
|
|
}
|
|
|
|
/* Find physical address for this virtual address. Normally used by
|
|
* I/O functions, but anyone can call it.
|
|
*/
|
|
unsigned long iopa(unsigned long addr)
|
|
{
|
|
unsigned long pa;
|
|
|
|
/* I don't know why this won't work on PMacs or CHRP. It
|
|
* appears there is some bug, or there is some implicit
|
|
* mapping done not properly represented by BATs or in page
|
|
* tables.......I am actively working on resolving this, but
|
|
* can't hold up other stuff. -- Dan
|
|
*/
|
|
pte_t *pte;
|
|
struct mm_struct *mm;
|
|
|
|
/* Check the BATs */
|
|
pa = v_mapped_by_bats(addr);
|
|
if (pa)
|
|
return pa;
|
|
|
|
/* Allow mapping of user addresses (within the thread)
|
|
* for DMA if necessary.
|
|
*/
|
|
if (addr < TASK_SIZE)
|
|
mm = current->mm;
|
|
else
|
|
mm = &init_mm;
|
|
|
|
pa = 0;
|
|
if (get_pteptr(mm, addr, &pte, NULL)) {
|
|
pa = (pte_val(*pte) & PAGE_MASK) | (addr & ~PAGE_MASK);
|
|
pte_unmap(pte);
|
|
}
|
|
|
|
return(pa);
|
|
}
|
|
|
|
/* This is will find the virtual address for a physical one....
|
|
* Swiped from APUS, could be dangerous :-).
|
|
* This is only a placeholder until I really find a way to make this
|
|
* work. -- Dan
|
|
*/
|
|
unsigned long
|
|
mm_ptov (unsigned long paddr)
|
|
{
|
|
unsigned long ret;
|
|
#if 0
|
|
if (paddr < 16*1024*1024)
|
|
ret = ZTWO_VADDR(paddr);
|
|
else {
|
|
int i;
|
|
|
|
for (i = 0; i < kmap_chunk_count;){
|
|
unsigned long phys = kmap_chunks[i++];
|
|
unsigned long size = kmap_chunks[i++];
|
|
unsigned long virt = kmap_chunks[i++];
|
|
if (paddr >= phys
|
|
&& paddr < (phys + size)){
|
|
ret = virt + paddr - phys;
|
|
goto exit;
|
|
}
|
|
}
|
|
|
|
ret = (unsigned long) __va(paddr);
|
|
}
|
|
exit:
|
|
#ifdef DEBUGPV
|
|
printk ("PTOV(%lx)=%lx\n", paddr, ret);
|
|
#endif
|
|
#else
|
|
ret = (unsigned long)paddr + KERNELBASE;
|
|
#endif
|
|
return ret;
|
|
}
|
|
|