1 files changed, 253 insertions, 46 deletions

diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c
index aff108df92d3..4224256bb215 100644
--- a/arch/xtensa/mm/init.c
+++ b/arch/xtensa/mm/init.c
@@ -8,6 +8,7 @@
  * for more details.
  *
  * Copyright (C) 2001 - 2005 Tensilica Inc.
+ * Copyright (C) 2014 Cadence Design Systems Inc.
  *
  * Chris Zankel <chris@zankel.net>
  * Joe Taylor   <joe@tensilica.com, joetylr@yahoo.com>
@@ -19,6 +20,7 @@
 #include <linux/errno.h>
 #include <linux/bootmem.h>
 #include <linux/gfp.h>
+#include <linux/highmem.h>
 #include <linux/swap.h>
 #include <linux/mman.h>
 #include <linux/nodemask.h>
@@ -27,11 +29,133 @@
 #include <asm/bootparam.h>
 #include <asm/page.h>
 #include <asm/sections.h>
+#include <asm/sysmem.h>
+
+struct sysmem_info sysmem __initdata;
+
+static void __init sysmem_dump(void)
+{
+        unsigned i;
+
+        pr_debug("Sysmem:\n");
+        for (i = 0; i < sysmem.nr_banks; ++i)
+                pr_debug("  0x%08lx - 0x%08lx (%ldK)\n",
+                         sysmem.bank[i].start, sysmem.bank[i].end,
+                         (sysmem.bank[i].end - sysmem.bank[i].start) >> 10);
+}
+
+/*
+ * Find bank with maximal .start such that bank.start <= start
+ */
+static inline struct meminfo * __init find_bank(unsigned long start)
+{
+        unsigned i;
+        struct meminfo *it = NULL;
+
+        for (i = 0; i < sysmem.nr_banks; ++i)
+                if (sysmem.bank[i].start <= start)
+                        it = sysmem.bank + i;
+                else
+                        break;
+        return it;
+}
+
+/*
+ * Move all memory banks starting at 'from' to a new place at 'to',
+ * adjust nr_banks accordingly.
+ * Both 'from' and 'to' must be inside the sysmem.bank.
+ *
+ * Returns: 0 (success), -ENOMEM (not enough space in the sysmem.bank).
+ */
+static int __init move_banks(struct meminfo *to, struct meminfo *from)
+{
+        unsigned n = sysmem.nr_banks - (from - sysmem.bank);
+
+        if (to > from && to - from + sysmem.nr_banks > SYSMEM_BANKS_MAX)
+                return -ENOMEM;
+        if (to != from)
+                memmove(to, from, n * sizeof(struct meminfo));
+        sysmem.nr_banks += to - from;
+        return 0;
+}
+
+/*
+ * Add new bank to sysmem. Resulting sysmem is the union of bytes of the
+ * original sysmem and the new bank.
+ *
+ * Returns: 0 (success), < 0 (error)
+ */
+int __init add_sysmem_bank(unsigned long start, unsigned long end)
+{
+        unsigned i;
+        struct meminfo *it = NULL;
+        unsigned long sz;
+        unsigned long bank_sz = 0;
+
+        if (start == end ||
+            (start < end) != (PAGE_ALIGN(start) < (end & PAGE_MASK))) {
+                pr_warn("Ignoring small memory bank 0x%08lx size: %ld bytes\n",
+                        start, end - start);
+                return -EINVAL;
+        }
+
+        start = PAGE_ALIGN(start);
+        end &= PAGE_MASK;
+        sz = end - start;
+
+        it = find_bank(start);
+
+        if (it)
+                bank_sz = it->end - it->start;
+
+        if (it && bank_sz >= start - it->start) {
+                if (end - it->start > bank_sz)
+                        it->end = end;
+                else
+                        return 0;
+        } else {
+                if (!it)
+                        it = sysmem.bank;
+                else
+                        ++it;
+
+                if (it - sysmem.bank < sysmem.nr_banks &&
+                    it->start - start <= sz) {
+                        it->start = start;
+                        if (it->end - it->start < sz)
+                                it->end = end;
+                        else
+                                return 0;
+                } else {
+                        if (move_banks(it + 1, it) < 0) {
+                                pr_warn("Ignoring memory bank 0x%08lx size %ld bytes\n",
+                                        start, end - start);
+                                return -EINVAL;
+                        }
+                        it->start = start;
+                        it->end = end;
+                        return 0;
+                }
+        }
+        sz = it->end - it->start;
+        for (i = it + 1 - sysmem.bank; i < sysmem.nr_banks; ++i)
+                if (sysmem.bank[i].start - it->start <= sz) {
+                        if (sz < sysmem.bank[i].end - it->start)
+                                it->end = sysmem.bank[i].end;
+                } else {
+                        break;
+                }
+
+        move_banks(it + 1, sysmem.bank + i);
+        return 0;
+}
 
 /*
  * mem_reserve(start, end, must_exist)
  *
  * Reserve some memory from the memory pool.
+ * If must_exist is set and a part of the region being reserved does not exist
+ * memory map is not altered.
  *
  * Parameters:
  *  start       Start of region,
@@ -39,53 +163,69 @@
  *  must_exist  Must exist in memory pool.
  *
  * Returns:
- *  0 (memory area couldn't be mapped)
- * -1 (success)
+ *  0 (success)
+ *  < 0 (error)
  */
 
 int __init mem_reserve(unsigned long start, unsigned long end, int must_exist)
 {
-        int i;
-
-        if (start == end)
-                return 0;
+        struct meminfo *it;
+        struct meminfo *rm = NULL;
+        unsigned long sz;
+        unsigned long bank_sz = 0;
 
         start = start & PAGE_MASK;
         end = PAGE_ALIGN(end);
+        sz = end - start;
+        if (!sz)
+                return -EINVAL;
 
-        for (i = 0; i < sysmem.nr_banks; i++)
-                if (start < sysmem.bank[i].end
-                    && end >= sysmem.bank[i].start)
-                        break;
+        it = find_bank(start);
+
+        if (it)
+                bank_sz = it->end - it->start;
 
-        if (i == sysmem.nr_banks) {
-                if (must_exist)
-                        printk (KERN_WARNING "mem_reserve: [0x%0lx, 0x%0lx) "
-                                "not in any region!\n", start, end);
-                return 0;
+        if ((!it || end - it->start > bank_sz) && must_exist) {
+                pr_warn("mem_reserve: [0x%0lx, 0x%0lx) not in any region!\n",
+                        start, end);
+                return -EINVAL;
         }
 
-        if (start > sysmem.bank[i].start) {
-                if (end < sysmem.bank[i].end) {
-                        /* split entry */
-                        if (sysmem.nr_banks >= SYSMEM_BANKS_MAX)
-                                panic("meminfo overflow\n");
-                        sysmem.bank[sysmem.nr_banks].start = end;
-                        sysmem.bank[sysmem.nr_banks].end = sysmem.bank[i].end;
-                        sysmem.nr_banks++;
+        if (it && start - it->start < bank_sz) {
+                if (start == it->start) {
+                        if (end - it->start < bank_sz) {
+                                it->start = end;
+                                return 0;
+                        } else {
+                                rm = it;
+                        }
+                } else {
+                        it->end = start;
+                        if (end - it->start < bank_sz)
+                                return add_sysmem_bank(end,
+                                                       it->start + bank_sz);
+                        ++it;
                 }
-                sysmem.bank[i].end = start;
+        }
 
-        } else if (end < sysmem.bank[i].end) {
-                sysmem.bank[i].start = end;
+        if (!it)
+                it = sysmem.bank;
 
-        } else {
-                /* remove entry */
-                sysmem.nr_banks--;
-                sysmem.bank[i].start = sysmem.bank[sysmem.nr_banks].start;
-                sysmem.bank[i].end   = sysmem.bank[sysmem.nr_banks].end;
+        for (; it < sysmem.bank + sysmem.nr_banks; ++it) {
+                if (it->end - start <= sz) {
+                        if (!rm)
+                                rm = it;
+                } else {
+                        if (it->start - start < sz)
+                                it->start = end;
+                        break;
+                }
         }
-        return -1;
+
+        if (rm)
+                move_banks(rm, it);
+
+        return 0;
 }
 
 
@@ -99,6 +239,7 @@ void __init bootmem_init(void)
         unsigned long bootmap_start, bootmap_size;
         int i;
 
+        sysmem_dump();
         max_low_pfn = max_pfn = 0;
         min_low_pfn = ~0;
 
@@ -156,19 +297,13 @@ void __init bootmem_init(void)
 
 void __init zones_init(void)
 {
-        unsigned long zones_size[MAX_NR_ZONES];
-        int i;
-
         /* All pages are DMA-able, so we put them all in the DMA zone. */
-
-        zones_size[ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET;
-        for (i = 1; i < MAX_NR_ZONES; i++)
-                zones_size[i] = 0;
-
+        unsigned long zones_size[MAX_NR_ZONES] = {
+                [ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET,
 #ifdef CONFIG_HIGHMEM
-        zones_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;
+                [ZONE_HIGHMEM] = max_pfn - max_low_pfn,
 #endif
-
+        };
         free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL);
 }
 
@@ -178,16 +313,38 @@ void __init zones_init(void)
 
 void __init mem_init(void)
 {
-        max_mapnr = max_low_pfn - ARCH_PFN_OFFSET;
-        high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
-
 #ifdef CONFIG_HIGHMEM
-#error HIGHGMEM not implemented in init.c
+        unsigned long tmp;
+
+        reset_all_zones_managed_pages();
+        for (tmp = max_low_pfn; tmp < max_pfn; tmp++)
+                free_highmem_page(pfn_to_page(tmp));
 #endif
 
+        max_mapnr = max_pfn - ARCH_PFN_OFFSET;
+        high_memory = (void *)__va(max_low_pfn << PAGE_SHIFT);
+
         free_all_bootmem();
 
         mem_init_print_info(NULL);
+        pr_info("virtual kernel memory layout:\n"
+#ifdef CONFIG_HIGHMEM
+                "    pkmap   : 0x%08lx - 0x%08lx  (%5lu kB)\n"
+                "    fixmap  : 0x%08lx - 0x%08lx  (%5lu kB)\n"
+#endif
+                "    vmalloc : 0x%08x - 0x%08x  (%5u MB)\n"
+                "    lowmem  : 0x%08x - 0x%08lx  (%5lu MB)\n",
+#ifdef CONFIG_HIGHMEM
+                PKMAP_BASE, PKMAP_BASE + LAST_PKMAP * PAGE_SIZE,
+                (LAST_PKMAP*PAGE_SIZE) >> 10,
+                FIXADDR_START, FIXADDR_TOP,
+                (FIXADDR_TOP - FIXADDR_START) >> 10,
+#endif
+                VMALLOC_START, VMALLOC_END,
+                (VMALLOC_END - VMALLOC_START) >> 20,
+                PAGE_OFFSET, PAGE_OFFSET +
+                (max_low_pfn - min_low_pfn) * PAGE_SIZE,
+                ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20);
 }
 
 #ifdef CONFIG_BLK_DEV_INITRD
@@ -204,3 +361,53 @@ void free_initmem(void)
 {
         free_initmem_default(-1);
 }
+
+static void __init parse_memmap_one(char *p)
+{
+        char *oldp;
+        unsigned long start_at, mem_size;
+
+        if (!p)
+                return;
+
+        oldp = p;
+        mem_size = memparse(p, &p);
+        if (p == oldp)
+                return;
+
+        switch (*p) {
+        case '@':
+                start_at = memparse(p + 1, &p);
+                add_sysmem_bank(start_at, start_at + mem_size);
+                break;
+
+        case '$':
+                start_at = memparse(p + 1, &p);
+                mem_reserve(start_at, start_at + mem_size, 0);
+                break;
+
+        case 0:
+                mem_reserve(mem_size, 0, 0);
+                break;
+
+        default:
+                pr_warn("Unrecognized memmap syntax: %s\n", p);
+                break;
+        }
+}
+
+static int __init parse_memmap_opt(char *str)
+{
+        while (str) {
+                char *k = strchr(str, ',');
+
+                if (k)
+                        *k++ = 0;
+
+                parse_memmap_one(str);
+                str = k;
+        }
+
+        return 0;
+}
+early_param("memmap", parse_memmap_opt);