/*
* Procedures for maintaining information about logical memory blocks.
*
* Peter Bergner, IBM Corp. June 2001.
* Copyright (C) 2001 Peter Bergner.
*
* 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/config.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <asm/types.h>
#include <asm/page.h>
#include <asm/prom.h>
#include <asm/lmb.h>
#ifdef CONFIG_PPC32
#include "mmu_decl.h" /* for __max_low_memory */
#endif
#undef DEBUG
#ifdef DEBUG
#include <asm/udbg.h>
#define DBG(fmt...) udbg_printf(fmt)
#else
#define DBG(fmt...)
#endif
struct lmb lmb;
void lmb_dump_all(void)
{
#ifdef DEBUG
unsigned long i;
DBG("lmb_dump_all:\n");
DBG(" memory.cnt = 0x%lx\n", lmb.memory.cnt);
DBG(" memory.size = 0x%lx\n", lmb.memory.size);
for (i=0; i < lmb.memory.cnt ;i++) {
DBG(" memory.region[0x%x].base = 0x%lx\n",
i, lmb.memory.region[i].base);
DBG(" .size = 0x%lx\n",
lmb.memory.region[i].size);
}
DBG("\n reserved.cnt = 0x%lx\n", lmb.reserved.cnt);
DBG(" reserved.size = 0x%lx\n", lmb.reserved.size);
for (i=0; i < lmb.reserved.cnt ;i++) {
DBG(" reserved.region[0x%x].base = 0x%lx\n",
i, lmb.reserved.region[i].base);
DBG(" .size = 0x%lx\n",
lmb.reserved.region[i].size);
}
#endif /* DEBUG */
}
static unsigned long __init lmb_addrs_overlap(unsigned long base1,
unsigned long size1, unsigned long base2, unsigned long size2)
{
return ((base1 < (base2+size2)) && (base2 < (base1+size1)));
}
static long __init lmb_addrs_adjacent(unsigned long base1, unsigned long size1,
unsigned long base2, unsigned long size2)
{
if (base2 == base1 + size1)
return 1;
else if (base1 == base2 + size2)
return -1;
return 0;
}
static long __init lmb_regions_adjacent(struct lmb_region *rgn,
unsigned long r1, unsigned long r2)
{
unsigned long base1 = rgn->region[r1].base;
unsigned long size1 = rgn->region[r1].size;
unsigned long base2 = rgn->region[r2].base;
unsigned long size2 = rgn->region[r2].size;
return lmb_addrs_adjacent(base1, size1, base2, size2);
}
/* Assumption: base addr of region 1 < base addr of region 2 */
static void __init lmb_coalesce_regions(struct lmb_region *rgn,
unsigned long r1, unsigned long r2)
{
unsigned long i;
rgn->region[r1].size += rgn->region[r2].size;
for (i=r2; i < rgn->cnt-1; i++) {
rgn->region[i].base = rgn->region[i+1].base;
rgn->region[i].size = rgn->region[i+1].size;
}
rgn->cnt--;
}
/* This routine called with relocation disabled. */
void __init lmb_init(void)
{
/* Create a dummy zero size LMB which will get coalesced away later.
* This simplifies the lmb_add() code below...
*/
lmb.memory.region[0].base = 0;
lmb.memory.region[0].size = 0;
lmb.memory.cnt = 1;
/* Ditto. */
lmb.reserved.region[0].base = 0;
lmb.reserved.region[0].size = 0;
lmb.reserved.cnt = 1;
}
/* This routine may be called with relocation disabled. */
void __init lmb_analyze(void)
{
int i;
lmb.memory.size = 0;
for (i = 0; i < lmb.memory.cnt; i++)
lmb.memory.size += lmb.memory.region[i].size;
}
/* This routine called with relocation disabled. */
static long __init lmb_add_region(struct lmb_region *rgn, unsigned long base,
unsigned long size)
{
unsigned long i, coalesced = 0;
long adjacent;
/* First try and coalesce this LMB with another. */
for (i=0; i < rgn->cnt; i++) {
unsigned long rgnbase = rgn->region[i].base;
unsigned long rgnsize = rgn->region[i].size;
adjacent = lmb_addrs_adjacent(base,size,rgnbase,rgnsize);
if ( adjacent > 0 ) {
rgn->region[i].base -= size;
rgn->region[i].size += size;
coalesced++;
break;
}
else if ( adjacent < 0 ) {
rgn->region[i].size += size;
coalesced++;
break;
}
}
if ((i < rgn->cnt-1) && lmb_regions_adjacent(rgn, i, i+1) ) {
lmb_coalesce_regions(rgn, i, i+1);
coalesced++;
}
if (coalesced)
return coalesced;
if (rgn->cnt >= MAX_LMB_REGIONS)
return -1;
/* Couldn't coalesce the LMB, so add it to the sorted table. */
for (i = rgn->cnt-1; i >= 0; i--) {
if (base < rgn->region[i].base) {
rgn->region[i+1].base = rgn->region[i].base;
rgn->region[i+1].size = rgn->region[i].size;
} else {
rgn->region[i+1].base = base;
rgn->region[i+1].size = size;
break;
}
}
rgn->cnt++;
return 0;
}
/* This routine may be called with relocation disabled. */
long __init lmb_add(unsigned long base, unsigned long size)
{
struct lmb_region *_rgn = &(lmb.memory);
/* On pSeries LPAR systems, the first LMB is our RMO region. */
if (base == 0)
lmb.rmo_size = size;
return lmb_add_region(_rgn, base, size);
}
long __init lmb_reserve(unsigned long base, unsigned long size)
{
struct lmb_region *_rgn = &(lmb.reserved);
return lmb_add_region(_rgn, base, size);
}
long __init lmb_overlaps_region(struct lmb_region *rgn, unsigned long base,
unsigned long size)
{
unsigned long i;
for (i=0; i < rgn->cnt; i++) {
unsigned long rgnbase = rgn->region[i].base;
unsigned long rgnsize = rgn->region[i].size;
if ( lmb_addrs_overlap(base,size,rgnbase,rgnsize) ) {
break;
}
}
return (i < rgn->cnt) ? i : -1;
}
unsigned long __init lmb_alloc(unsigned long size, unsigned long align)
{
return lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE);
}
unsigned long __init lmb_alloc_base(unsigned long size, unsigned long align,
unsigned long max_addr)
{
long i, j;
unsigned long base = 0;
#ifdef CONFIG_PPC32
/* On 32-bit, make sure we allocate lowmem */
if (max_addr == LMB_ALLOC_ANYWHERE)
max_addr = __max_low_memory;
#endif
for (i = lmb.memory.cnt-1; i >= 0; i--) {
unsigned long lmbbase = lmb.memory.region[i].base;
unsigned long lmbsize = lmb.memory.region[i].size;
if (max_addr == LMB_ALLOC_ANYWHERE)
base = _ALIGN_DOWN(lmbbase + lmbsize - size, align);
else if (lmbbase < max_addr) {
base = min(lmbbase + lmbsize, max_addr);
base = _ALIGN_DOWN(base - size, align);
} else
continue;
while ((lmbbase <= base) &&
((j = lmb_overlaps_region(&lmb.reserved, base, size)) >= 0) )
base = _ALIGN_DOWN(lmb.reserved.region[j].base - size,
align);
if ((base != 0) && (lmbbase <= base))
break;
}
if (i < 0)
return 0;
lmb_add_region(&lmb.reserved, base, size);
return base;
}
/* You must call lmb_analyze() before this. */
unsigned long __init lmb_phys_mem_size(void)
{
return lmb.memory.size;
}
unsigned long __init lmb_end_of_DRAM(void)
{
int idx = lmb.memory.cnt - 1;
return (lmb.memory.region[idx].base + lmb.memory.region[idx].size);
}
/*
* Truncate the lmb list to memory_limit if it's set
* You must call lmb_analyze() after this.
*/
void __init lmb_enforce_memory_limit(unsigned long memory_limit)
{
unsigned long i, limit;
if (! memory_limit)
return;
limit = memory_limit;
for (i = 0; i < lmb.memory.cnt; i++) {
if (limit > lmb.memory.region[i].size) {
limit -= lmb.memory.region[i].size;
continue;
}
lmb.memory.region[i].size = limit;
lmb.memory.cnt = i + 1;
break;
}
}
