1 files changed, 370 insertions, 0 deletions

diff --git a/lib/lmb.c b/lib/lmb.c
new file mode 100644
index 000000000000..3c43b95fef4a
--- /dev/null
+++ b/lib/lmb.c
@@ -0,0 +1,370 @@
+/*
+ * 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/kernel.h>
+#include <linux/init.h>
+#include <linux/bitops.h>
+#include <linux/lmb.h>
+
+#undef DEBUG
+
+#ifdef DEBUG
+#define DBG(fmt...) LMB_DBG(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+#define LMB_ALLOC_ANYWHERE      0
+
+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%llx\n",
+            (unsigned long long)lmb.memory.size);
+        for (i=0; i < lmb.memory.cnt ;i++) {
+                DBG("    memory.region[0x%x].base       = 0x%llx\n",
+                    i, (unsigned long long)lmb.memory.region[i].base);
+                DBG("                 .size     = 0x%llx\n",
+                    (unsigned long long)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%llx\n",
+                    i, (unsigned long long)lmb.reserved.region[i].base);
+                DBG("                 .size     = 0x%llx\n",
+                    (unsigned long long)lmb.reserved.region[i].size);
+        }
+#endif /* DEBUG */
+}
+
+static unsigned long __init lmb_addrs_overlap(u64 base1,
+                u64 size1, u64 base2, u64 size2)
+{
+        return ((base1 < (base2+size2)) && (base2 < (base1+size1)));
+}
+
+static long __init lmb_addrs_adjacent(u64 base1, u64 size1,
+                u64 base2, u64 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)
+{
+        u64 base1 = rgn->region[r1].base;
+        u64 size1 = rgn->region[r1].size;
+        u64 base2 = rgn->region[r2].base;
+        u64 size2 = rgn->region[r2].size;
+
+        return lmb_addrs_adjacent(base1, size1, base2, size2);
+}
+
+static void __init 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 __init 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);
+}
+
+/* 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, u64 base, u64 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++) {
+                u64 rgnbase = rgn->region[i].base;
+                u64 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 __init lmb_add(u64 base, u64 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(u64 base, u64 size)
+{
+        struct lmb_region *_rgn = &(lmb.reserved);
+
+        BUG_ON(0 == size);
+
+        return lmb_add_region(_rgn, base, size);
+}
+
+long __init lmb_overlaps_region(struct lmb_region *rgn, u64 base,
+                                u64 size)
+{
+        unsigned long i;
+
+        for (i=0; i < rgn->cnt; i++) {
+                u64 rgnbase = rgn->region[i].base;
+                u64 rgnsize = rgn->region[i].size;
+                if ( lmb_addrs_overlap(base,size,rgnbase,rgnsize) ) {
+                        break;
+                }
+        }
+
+        return (i < rgn->cnt) ? i : -1;
+}
+
+u64 __init lmb_alloc(u64 size, u64 align)
+{
+        return lmb_alloc_base(size, align, LMB_ALLOC_ANYWHERE);
+}
+
+u64 __init lmb_alloc_base(u64 size, u64 align, u64 max_addr)
+{
+        u64 alloc;
+
+        alloc = __lmb_alloc_base(size, align, max_addr);
+
+        if (alloc == 0)
+                panic("ERROR: Failed to allocate 0x%llx bytes below 0x%llx.\n",
+                      (unsigned long long) size, (unsigned long long) max_addr);
+
+        return alloc;
+}
+
+static u64 lmb_align_down(u64 addr, u64 size)
+{
+        return addr & ~(size - 1);
+}
+
+static u64 lmb_align_up(u64 addr, u64 size)
+{
+        return (addr + (size - 1)) & ~(size - 1);
+}
+
+u64 __init __lmb_alloc_base(u64 size, u64 align, u64 max_addr)
+{
+        long i, j;
+        u64 base = 0;
+
+        BUG_ON(0 == size);
+
+        /* On some platforms, make sure we allocate lowmem */
+        if (max_addr == LMB_ALLOC_ANYWHERE)
+                max_addr = LMB_REAL_LIMIT;
+
+        for (i = lmb.memory.cnt-1; i >= 0; i--) {
+                u64 lmbbase = lmb.memory.region[i].base;
+                u64 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;
+}
+
+/* You must call lmb_analyze() before this. */
+u64 __init lmb_phys_mem_size(void)
+{
+        return lmb.memory.size;
+}
+
+u64 __init lmb_end_of_DRAM(void)
+{
+        int idx = lmb.memory.cnt - 1;
+
+        return (lmb.memory.region[idx].base + lmb.memory.region[idx].size);
+}
+
+/* You must call lmb_analyze() after this. */
+void __init lmb_enforce_memory_limit(u64 memory_limit)
+{
+        unsigned long i;
+        u64 limit;
+        struct lmb_property *p;
+
+        if (! memory_limit)
+                return;
+
+        /* Truncate the lmb regions to satisfy the memory limit. */
+        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;
+        }
+
+        if (lmb.memory.region[0].size < lmb.rmo_size)
+                lmb.rmo_size = lmb.memory.region[0].size;
+
+        /* And truncate any reserves above the limit also. */
+        for (i = 0; i < lmb.reserved.cnt; i++) {
+                p = &lmb.reserved.region[i];
+
+                if (p->base > memory_limit)
+                        p->size = 0;
+                else if ((p->base + p->size) > memory_limit)
+                        p->size = memory_limit - p->base;
+
+                if (p->size == 0) {
+                        lmb_remove_region(&lmb.reserved, i);
+                        i--;
+                }
+        }
+}
+
+int __init lmb_is_reserved(u64 addr)
+{
+        int i;
+
+        for (i = 0; i < lmb.reserved.cnt; i++) {
+                u64 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;
+}