linux/arch/powerpc/mm/ppc_mmu_32.c
David Gibson 8e561e7eda [POWERPC] Kill typedef-ed structs for hash PTEs and BATs
Using typedefs to rename structure types if frowned on by CodingStyle.
However, we do so for the hash PTE structure on both ppc32 (where it's
called "PTE") and ppc64 (where it's called "hpte_t").  On ppc32 we
also have such a typedef for the BATs ("BAT").

This removes this unhelpful use of typedefs, in the process
bringing ppc32 and ppc64 closer together, by using the name "struct
hash_pte" in both cases.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-06-14 22:30:16 +10:00

291 lines
8.2 KiB
C

/*
* This file contains the routines for handling the MMU on those
* PowerPC implementations where the MMU substantially follows the
* architecture specification. This includes the 6xx, 7xx, 7xxx,
* 8260, and POWER3 implementations but excludes the 8xx and 4xx.
* -- 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
*
* 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/mm.h>
#include <linux/init.h>
#include <linux/highmem.h>
#include <asm/prom.h>
#include <asm/mmu.h>
#include <asm/machdep.h>
#include <asm/lmb.h>
#include "mmu_decl.h"
struct hash_pte *Hash, *Hash_end;
unsigned long Hash_size, Hash_mask;
unsigned long _SDR1;
union ubat { /* BAT register values to be loaded */
struct ppc_bat bat;
u32 word[2];
} BATS[8][2]; /* 8 pairs of IBAT, DBAT */
struct batrange { /* stores address ranges mapped by BATs */
unsigned long start;
unsigned long limit;
unsigned long phys;
} bat_addrs[8];
/*
* Return PA for this VA if it is mapped by a BAT, or 0
*/
unsigned long v_mapped_by_bats(unsigned long va)
{
int b;
for (b = 0; b < 4; ++b)
if (va >= bat_addrs[b].start && va < bat_addrs[b].limit)
return bat_addrs[b].phys + (va - bat_addrs[b].start);
return 0;
}
/*
* Return VA for a given PA or 0 if not mapped
*/
unsigned long p_mapped_by_bats(unsigned long pa)
{
int b;
for (b = 0; b < 4; ++b)
if (pa >= bat_addrs[b].phys
&& pa < (bat_addrs[b].limit-bat_addrs[b].start)
+bat_addrs[b].phys)
return bat_addrs[b].start+(pa-bat_addrs[b].phys);
return 0;
}
unsigned long __init mmu_mapin_ram(void)
{
#ifdef CONFIG_POWER4
return 0;
#else
unsigned long tot, bl, done;
unsigned long max_size = (256<<20);
unsigned long align;
if (__map_without_bats) {
printk(KERN_DEBUG "RAM mapped without BATs\n");
return 0;
}
/* Set up BAT2 and if necessary BAT3 to cover RAM. */
/* Make sure we don't map a block larger than the
smallest alignment of the physical address. */
/* alignment of PPC_MEMSTART */
align = ~(PPC_MEMSTART-1) & PPC_MEMSTART;
/* set BAT block size to MIN(max_size, align) */
if (align && align < max_size)
max_size = align;
tot = total_lowmem;
for (bl = 128<<10; bl < max_size; bl <<= 1) {
if (bl * 2 > tot)
break;
}
setbat(2, KERNELBASE, PPC_MEMSTART, bl, _PAGE_RAM);
done = (unsigned long)bat_addrs[2].limit - KERNELBASE + 1;
if ((done < tot) && !bat_addrs[3].limit) {
/* use BAT3 to cover a bit more */
tot -= done;
for (bl = 128<<10; bl < max_size; bl <<= 1)
if (bl * 2 > tot)
break;
setbat(3, KERNELBASE+done, PPC_MEMSTART+done, bl, _PAGE_RAM);
done = (unsigned long)bat_addrs[3].limit - KERNELBASE + 1;
}
return done;
#endif
}
/*
* Set up one of the I/D BAT (block address translation) register pairs.
* The parameters are not checked; in particular size must be a power
* of 2 between 128k and 256M.
*/
void __init setbat(int index, unsigned long virt, unsigned long phys,
unsigned int size, int flags)
{
unsigned int bl;
int wimgxpp;
union ubat *bat = BATS[index];
if (((flags & _PAGE_NO_CACHE) == 0) &&
cpu_has_feature(CPU_FTR_NEED_COHERENT))
flags |= _PAGE_COHERENT;
bl = (size >> 17) - 1;
if (PVR_VER(mfspr(SPRN_PVR)) != 1) {
/* 603, 604, etc. */
/* Do DBAT first */
wimgxpp = flags & (_PAGE_WRITETHRU | _PAGE_NO_CACHE
| _PAGE_COHERENT | _PAGE_GUARDED);
wimgxpp |= (flags & _PAGE_RW)? BPP_RW: BPP_RX;
bat[1].word[0] = virt | (bl << 2) | 2; /* Vs=1, Vp=0 */
bat[1].word[1] = phys | wimgxpp;
#ifndef CONFIG_KGDB /* want user access for breakpoints */
if (flags & _PAGE_USER)
#endif
bat[1].bat.batu.vp = 1;
if (flags & _PAGE_GUARDED) {
/* G bit must be zero in IBATs */
bat[0].word[0] = bat[0].word[1] = 0;
} else {
/* make IBAT same as DBAT */
bat[0] = bat[1];
}
} else {
/* 601 cpu */
if (bl > BL_8M)
bl = BL_8M;
wimgxpp = flags & (_PAGE_WRITETHRU | _PAGE_NO_CACHE
| _PAGE_COHERENT);
wimgxpp |= (flags & _PAGE_RW)?
((flags & _PAGE_USER)? PP_RWRW: PP_RWXX): PP_RXRX;
bat->word[0] = virt | wimgxpp | 4; /* Ks=0, Ku=1 */
bat->word[1] = phys | bl | 0x40; /* V=1 */
}
bat_addrs[index].start = virt;
bat_addrs[index].limit = virt + ((bl + 1) << 17) - 1;
bat_addrs[index].phys = phys;
}
/*
* Preload a translation in the hash table
*/
void hash_preload(struct mm_struct *mm, unsigned long ea,
unsigned long access, unsigned long trap)
{
pmd_t *pmd;
if (Hash == 0)
return;
pmd = pmd_offset(pud_offset(pgd_offset(mm, ea), ea), ea);
if (!pmd_none(*pmd))
add_hash_page(mm->context.id, ea, pmd_val(*pmd));
}
/*
* Initialize the hash table and patch the instructions in hashtable.S.
*/
void __init MMU_init_hw(void)
{
unsigned int hmask, mb, mb2;
unsigned int n_hpteg, lg_n_hpteg;
extern unsigned int hash_page_patch_A[];
extern unsigned int hash_page_patch_B[], hash_page_patch_C[];
extern unsigned int hash_page[];
extern unsigned int flush_hash_patch_A[], flush_hash_patch_B[];
if (!cpu_has_feature(CPU_FTR_HPTE_TABLE)) {
/*
* Put a blr (procedure return) instruction at the
* start of hash_page, since we can still get DSI
* exceptions on a 603.
*/
hash_page[0] = 0x4e800020;
flush_icache_range((unsigned long) &hash_page[0],
(unsigned long) &hash_page[1]);
return;
}
if ( ppc_md.progress ) ppc_md.progress("hash:enter", 0x105);
#define LG_HPTEG_SIZE 6 /* 64 bytes per HPTEG */
#define SDR1_LOW_BITS ((n_hpteg - 1) >> 10)
#define MIN_N_HPTEG 1024 /* min 64kB hash table */
/*
* Allow 1 HPTE (1/8 HPTEG) for each page of memory.
* This is less than the recommended amount, but then
* Linux ain't AIX.
*/
n_hpteg = total_memory / (PAGE_SIZE * 8);
if (n_hpteg < MIN_N_HPTEG)
n_hpteg = MIN_N_HPTEG;
lg_n_hpteg = __ilog2(n_hpteg);
if (n_hpteg & (n_hpteg - 1)) {
++lg_n_hpteg; /* round up if not power of 2 */
n_hpteg = 1 << lg_n_hpteg;
}
Hash_size = n_hpteg << LG_HPTEG_SIZE;
/*
* Find some memory for the hash table.
*/
if ( ppc_md.progress ) ppc_md.progress("hash:find piece", 0x322);
Hash = __va(lmb_alloc_base(Hash_size, Hash_size,
__initial_memory_limit));
cacheable_memzero(Hash, Hash_size);
_SDR1 = __pa(Hash) | SDR1_LOW_BITS;
Hash_end = (struct hash_pte *) ((unsigned long)Hash + Hash_size);
printk("Total memory = %ldMB; using %ldkB for hash table (at %p)\n",
total_memory >> 20, Hash_size >> 10, Hash);
/*
* Patch up the instructions in hashtable.S:create_hpte
*/
if ( ppc_md.progress ) ppc_md.progress("hash:patch", 0x345);
Hash_mask = n_hpteg - 1;
hmask = Hash_mask >> (16 - LG_HPTEG_SIZE);
mb2 = mb = 32 - LG_HPTEG_SIZE - lg_n_hpteg;
if (lg_n_hpteg > 16)
mb2 = 16 - LG_HPTEG_SIZE;
hash_page_patch_A[0] = (hash_page_patch_A[0] & ~0xffff)
| ((unsigned int)(Hash) >> 16);
hash_page_patch_A[1] = (hash_page_patch_A[1] & ~0x7c0) | (mb << 6);
hash_page_patch_A[2] = (hash_page_patch_A[2] & ~0x7c0) | (mb2 << 6);
hash_page_patch_B[0] = (hash_page_patch_B[0] & ~0xffff) | hmask;
hash_page_patch_C[0] = (hash_page_patch_C[0] & ~0xffff) | hmask;
/*
* Ensure that the locations we've patched have been written
* out from the data cache and invalidated in the instruction
* cache, on those machines with split caches.
*/
flush_icache_range((unsigned long) &hash_page_patch_A[0],
(unsigned long) &hash_page_patch_C[1]);
/*
* Patch up the instructions in hashtable.S:flush_hash_page
*/
flush_hash_patch_A[0] = (flush_hash_patch_A[0] & ~0xffff)
| ((unsigned int)(Hash) >> 16);
flush_hash_patch_A[1] = (flush_hash_patch_A[1] & ~0x7c0) | (mb << 6);
flush_hash_patch_A[2] = (flush_hash_patch_A[2] & ~0x7c0) | (mb2 << 6);
flush_hash_patch_B[0] = (flush_hash_patch_B[0] & ~0xffff) | hmask;
flush_icache_range((unsigned long) &flush_hash_patch_A[0],
(unsigned long) &flush_hash_patch_B[1]);
if ( ppc_md.progress ) ppc_md.progress("hash:done", 0x205);
}