Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / arch / xtensa / mm / init.c
diff --git a/kernel/arch/xtensa/mm/init.c b/kernel/arch/xtensa/mm/init.c
new file mode 100644 (file)
index 0000000..9a9a593
--- /dev/null
@@ -0,0 +1,430 @@
+/*
+ * arch/xtensa/mm/init.c
+ *
+ * Derived from MIPS, PPC.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * 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>
+ * Marc Gauthier
+ * Kevin Chea
+ */
+
+#include <linux/kernel.h>
+#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>
+#include <linux/mm.h>
+
+#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,
+ *  end                End of region,
+ *  must_exist Must exist in memory pool.
+ *
+ * Returns:
+ *  0 (success)
+ *  < 0 (error)
+ */
+
+int __init mem_reserve(unsigned long start, unsigned long end, int must_exist)
+{
+       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;
+
+       it = find_bank(start);
+
+       if (it)
+               bank_sz = it->end - it->start;
+
+       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 (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;
+               }
+       }
+
+       if (!it)
+               it = sysmem.bank;
+
+       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;
+               }
+       }
+
+       if (rm)
+               move_banks(rm, it);
+
+       return 0;
+}
+
+
+/*
+ * Initialize the bootmem system and give it all low memory we have available.
+ */
+
+void __init bootmem_init(void)
+{
+       unsigned long pfn;
+       unsigned long bootmap_start, bootmap_size;
+       int i;
+
+       /* Reserve all memory below PLATFORM_DEFAULT_MEM_START, as memory
+        * accounting doesn't work for pages below that address.
+        *
+        * If PLATFORM_DEFAULT_MEM_START is zero reserve page at address 0:
+        * successfull allocations should never return NULL.
+        */
+       if (PLATFORM_DEFAULT_MEM_START)
+               mem_reserve(0, PLATFORM_DEFAULT_MEM_START, 0);
+       else
+               mem_reserve(0, 1, 0);
+
+       sysmem_dump();
+       max_low_pfn = max_pfn = 0;
+       min_low_pfn = ~0;
+
+       for (i=0; i < sysmem.nr_banks; i++) {
+               pfn = PAGE_ALIGN(sysmem.bank[i].start) >> PAGE_SHIFT;
+               if (pfn < min_low_pfn)
+                       min_low_pfn = pfn;
+               pfn = PAGE_ALIGN(sysmem.bank[i].end - 1) >> PAGE_SHIFT;
+               if (pfn > max_pfn)
+                       max_pfn = pfn;
+       }
+
+       if (min_low_pfn > max_pfn)
+               panic("No memory found!\n");
+
+       max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ?
+               max_pfn : MAX_MEM_PFN >> PAGE_SHIFT;
+
+       /* Find an area to use for the bootmem bitmap. */
+
+       bootmap_size = bootmem_bootmap_pages(max_low_pfn - min_low_pfn);
+       bootmap_size <<= PAGE_SHIFT;
+       bootmap_start = ~0;
+
+       for (i=0; i<sysmem.nr_banks; i++)
+               if (sysmem.bank[i].end - sysmem.bank[i].start >= bootmap_size) {
+                       bootmap_start = sysmem.bank[i].start;
+                       break;
+               }
+
+       if (bootmap_start == ~0UL)
+               panic("Cannot find %ld bytes for bootmap\n", bootmap_size);
+
+       /* Reserve the bootmem bitmap area */
+
+       mem_reserve(bootmap_start, bootmap_start + bootmap_size, 1);
+       bootmap_size = init_bootmem_node(NODE_DATA(0),
+                                        bootmap_start >> PAGE_SHIFT,
+                                        min_low_pfn,
+                                        max_low_pfn);
+
+       /* Add all remaining memory pieces into the bootmem map */
+
+       for (i = 0; i < sysmem.nr_banks; i++) {
+               if (sysmem.bank[i].start >> PAGE_SHIFT < max_low_pfn) {
+                       unsigned long end = min(max_low_pfn << PAGE_SHIFT,
+                                               sysmem.bank[i].end);
+                       free_bootmem(sysmem.bank[i].start,
+                                    end - sysmem.bank[i].start);
+               }
+       }
+
+}
+
+
+void __init zones_init(void)
+{
+       /* All pages are DMA-able, so we put them all in the DMA zone. */
+       unsigned long zones_size[MAX_NR_ZONES] = {
+               [ZONE_DMA] = max_low_pfn - ARCH_PFN_OFFSET,
+#ifdef CONFIG_HIGHMEM
+               [ZONE_HIGHMEM] = max_pfn - max_low_pfn,
+#endif
+       };
+       free_area_init_node(0, zones_size, ARCH_PFN_OFFSET, NULL);
+}
+
+/*
+ * Initialize memory pages.
+ */
+
+void __init mem_init(void)
+{
+#ifdef CONFIG_HIGHMEM
+       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
+#ifdef CONFIG_MMU
+               "    vmalloc : 0x%08x - 0x%08x  (%5u MB)\n"
+#endif
+               "    lowmem  : 0x%08lx - 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
+#ifdef CONFIG_MMU
+               VMALLOC_START, VMALLOC_END,
+               (VMALLOC_END - VMALLOC_START) >> 20,
+               PAGE_OFFSET, PAGE_OFFSET +
+               (max_low_pfn - min_low_pfn) * PAGE_SIZE,
+#else
+               min_low_pfn * PAGE_SIZE, max_low_pfn * PAGE_SIZE,
+#endif
+               ((max_low_pfn - min_low_pfn) * PAGE_SIZE) >> 20);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+extern int initrd_is_mapped;
+
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+       if (initrd_is_mapped)
+               free_reserved_area((void *)start, (void *)end, -1, "initrd");
+}
+#endif
+
+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);