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-rw-r--r--kernel/arch/xtensa/mm/init.c430
1 files changed, 430 insertions, 0 deletions
diff --git a/kernel/arch/xtensa/mm/init.c b/kernel/arch/xtensa/mm/init.c
new file mode 100644
index 000000000..9a9a5935b
--- /dev/null
+++ b/kernel/arch/xtensa/mm/init.c
@@ -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);