diff options
Diffstat (limited to 'lib_generic/lmb.c')
| -rw-r--r-- | lib_generic/lmb.c | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/lib_generic/lmb.c b/lib_generic/lmb.c new file mode 100644 index 0000000000..3b8c805e88 --- /dev/null +++ b/lib_generic/lmb.c @@ -0,0 +1,280 @@ +/* + * 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 <common.h> +#include <lmb.h> + +#define LMB_ALLOC_ANYWHERE 0 + +void lmb_dump_all(struct lmb *lmb) +{ +#ifdef DEBUG + unsigned long i; + + debug("lmb_dump_all:\n"); + debug(" memory.cnt = 0x%lx\n", lmb->memory.cnt); + debug(" memory.size = 0x%08x\n", lmb->memory.size); + for (i=0; i < lmb->memory.cnt ;i++) { + debug(" memory.reg[0x%x].base = 0x%08x\n", i, + lmb->memory.region[i].base); + debug(" .size = 0x%08x\n", + lmb->memory.region[i].size); + } + + debug("\n reserved.cnt = 0x%lx\n", lmb->reserved.cnt); + debug(" reserved.size = 0x%08x\n", lmb->reserved.size); + for (i=0; i < lmb->reserved.cnt ;i++) { + debug(" reserved.reg[0x%x].base = 0x%08x\n", i, + lmb->reserved.region[i].base); + debug(" .size = 0x%08x\n", + lmb->reserved.region[i].size); + } +#endif /* DEBUG */ +} + +static unsigned long lmb_addrs_overlap(ulong base1, + ulong size1, ulong base2, ulong size2) +{ + return ((base1 < (base2+size2)) && (base2 < (base1+size1))); +} + +static long lmb_addrs_adjacent(ulong base1, ulong size1, + ulong base2, ulong size2) +{ + if (base2 == base1 + size1) + return 1; + else if (base1 == base2 + size2) + return -1; + + return 0; +} + +static long lmb_regions_adjacent(struct lmb_region *rgn, + unsigned long r1, unsigned long r2) +{ + ulong base1 = rgn->region[r1].base; + ulong size1 = rgn->region[r1].size; + ulong base2 = rgn->region[r2].base; + ulong size2 = rgn->region[r2].size; + + return lmb_addrs_adjacent(base1, size1, base2, size2); +} + +static void lmb_remove_region(struct lmb_region *rgn, unsigned long r) +{ + unsigned long i; + + for (i = r; 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--; +} + +/* Assumption: base addr of region 1 < base addr of region 2 */ +static void lmb_coalesce_regions(struct lmb_region *rgn, + unsigned long r1, unsigned long r2) +{ + rgn->region[r1].size += rgn->region[r2].size; + lmb_remove_region(rgn, r2); +} + +void lmb_init(struct lmb *lmb) +{ + /* 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; + lmb->memory.size = 0; + + /* Ditto. */ + lmb->reserved.region[0].base = 0; + lmb->reserved.region[0].size = 0; + lmb->reserved.cnt = 1; + lmb->reserved.size = 0; +} + +/* This routine called with relocation disabled. */ +static long lmb_add_region(struct lmb_region *rgn, ulong base, ulong size) +{ + unsigned long coalesced = 0; + long adjacent, i; + + if ((rgn->cnt == 1) && (rgn->region[0].size == 0)) { + rgn->region[0].base = base; + rgn->region[0].size = size; + return 0; + } + + /* First try and coalesce this LMB with another. */ + for (i=0; i < rgn->cnt; i++) { + ulong rgnbase = rgn->region[i].base; + ulong rgnsize = rgn->region[i].size; + + if ((rgnbase == base) && (rgnsize == size)) + /* Already have this region, so we're done */ + return 0; + + 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; + } + } + + if (base < rgn->region[0].base) { + rgn->region[0].base = base; + rgn->region[0].size = size; + } + + rgn->cnt++; + + return 0; +} + +/* This routine may be called with relocation disabled. */ +long lmb_add(struct lmb *lmb, ulong base, ulong size) +{ + struct lmb_region *_rgn = &(lmb->memory); + + return lmb_add_region(_rgn, base, size); +} + +long lmb_reserve(struct lmb *lmb, ulong base, ulong size) +{ + struct lmb_region *_rgn = &(lmb->reserved); + + return lmb_add_region(_rgn, base, size); +} + +long lmb_overlaps_region(struct lmb_region *rgn, ulong base, + ulong size) +{ + unsigned long i; + + for (i=0; i < rgn->cnt; i++) { + ulong rgnbase = rgn->region[i].base; + ulong rgnsize = rgn->region[i].size; + if ( lmb_addrs_overlap(base,size,rgnbase,rgnsize) ) { + break; + } + } + + return (i < rgn->cnt) ? i : -1; +} + +ulong lmb_alloc(struct lmb *lmb, ulong size, ulong align) +{ + return lmb_alloc_base(lmb, size, align, LMB_ALLOC_ANYWHERE); +} + +ulong lmb_alloc_base(struct lmb *lmb, ulong size, ulong align, ulong max_addr) +{ + ulong alloc; + + alloc = __lmb_alloc_base(lmb, size, align, max_addr); + + if (alloc == 0) + printf("ERROR: Failed to allocate 0x%lx bytes below 0x%lx.\n", + size, max_addr); + + return alloc; +} + +static ulong lmb_align_down(ulong addr, ulong size) +{ + return addr & ~(size - 1); +} + +static ulong lmb_align_up(ulong addr, ulong size) +{ + return (addr + (size - 1)) & ~(size - 1); +} + +ulong __lmb_alloc_base(struct lmb *lmb, ulong size, ulong align, ulong max_addr) +{ + long i, j; + ulong base = 0; + + for (i = lmb->memory.cnt-1; i >= 0; i--) { + ulong lmbbase = lmb->memory.region[i].base; + ulong lmbsize = lmb->memory.region[i].size; + + if (max_addr == LMB_ALLOC_ANYWHERE) + base = lmb_align_down(lmbbase + lmbsize - size, align); + else if (lmbbase < max_addr) { + base = min(lmbbase + lmbsize, max_addr); + base = lmb_align_down(base - size, align); + } else + continue; + + while ((lmbbase <= base) && + ((j = lmb_overlaps_region(&(lmb->reserved), base, size)) >= 0) ) + base = lmb_align_down(lmb->reserved.region[j].base - size, + align); + + if ((base != 0) && (lmbbase <= base)) + break; + } + + if (i < 0) + return 0; + + if (lmb_add_region(&(lmb->reserved), base, lmb_align_up(size, align)) < 0) + return 0; + + return base; +} + +int lmb_is_reserved(struct lmb *lmb, ulong addr) +{ + int i; + + for (i = 0; i < lmb->reserved.cnt; i++) { + ulong upper = lmb->reserved.region[i].base + + lmb->reserved.region[i].size - 1; + if ((addr >= lmb->reserved.region[i].base) && (addr <= upper)) + return 1; + } + return 0; +} |