diff options
Diffstat (limited to 'arch/powerpc/mm/lmb.c')
| -rw-r--r-- | arch/powerpc/mm/lmb.c | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/arch/powerpc/mm/lmb.c b/arch/powerpc/mm/lmb.c new file mode 100644 index 000000000000..9b5aa6808eb8 --- /dev/null +++ b/arch/powerpc/mm/lmb.c @@ -0,0 +1,296 @@ +/* + * 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 + +struct lmb lmb; + +#undef DEBUG + +void lmb_dump_all(void) +{ +#ifdef DEBUG + unsigned long i; + + udbg_printf("lmb_dump_all:\n"); + udbg_printf(" memory.cnt = 0x%lx\n", + lmb.memory.cnt); + udbg_printf(" memory.size = 0x%lx\n", + lmb.memory.size); + for (i=0; i < lmb.memory.cnt ;i++) { + udbg_printf(" memory.region[0x%x].base = 0x%lx\n", + i, lmb.memory.region[i].base); + udbg_printf(" .size = 0x%lx\n", + lmb.memory.region[i].size); + } + + udbg_printf("\n reserved.cnt = 0x%lx\n", + lmb.reserved.cnt); + udbg_printf(" reserved.size = 0x%lx\n", + lmb.reserved.size); + for (i=0; i < lmb.reserved.cnt ;i++) { + udbg_printf(" reserved.region[0x%x].base = 0x%lx\n", + i, lmb.reserved.region[i].base); + udbg_printf(" .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; + } +} |