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-rw-r--r--arch/powerpc/mm/lmb.c296
1 files changed, 296 insertions, 0 deletions
diff --git a/arch/powerpc/mm/lmb.c b/arch/powerpc/mm/lmb.c
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+++ b/arch/powerpc/mm/lmb.c
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+/*
+ * 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;
+ }
+}