powerpc: Merge lmb.c and make MM initialization use it.

This also creates merged versions of do_init_bootmem, paging_init
and mem_init and moves them to arch/powerpc/mm/mem.c.  It gets rid
of the mem_pieces stuff.

I made memory_limit a parameter to lmb_enforce_memory_limit rather
than a global referenced by that function.  This will require some
small changes to ppc64 if we want to continue building ARCH=ppc64
using the merged lmb.c.

Signed-off-by: Paul Mackerras <paulus@samba.org>

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;
+        }
+}