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