arch/arc/mm/init.c - third_party/linux - Git at Google

 /*
  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/bootmem.h>
 #include <linux/memblock.h>
 #ifdef CONFIG_BLK_DEV_INITRD
 #include <linux/initrd.h>
 #endif
 #include <linux/of_fdt.h>
 #include <linux/swap.h>
 #include <linux/module.h>
 #include <linux/highmem.h>
 #include <asm/page.h>
 #include <asm/pgalloc.h>
 #include <asm/sections.h>
 #include <asm/arcregs.h>

 pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE);
 char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE);
 EXPORT_SYMBOL(empty_zero_page);

 static const unsigned long low_mem_start = CONFIG_LINUX_LINK_BASE;
 static unsigned long low_mem_sz;

 #ifdef CONFIG_HIGHMEM
 static unsigned long min_high_pfn, max_high_pfn;
 static u64 high_mem_start;
 static u64 high_mem_sz;
 #endif

 #ifdef CONFIG_DISCONTIGMEM
 struct pglist_data node_data[MAX_NUMNODES] __read_mostly;
 EXPORT_SYMBOL(node_data);
 #endif

 long __init arc_get_mem_sz(void)
 {
 	return low_mem_sz;
 }

 /* User can over-ride above with "mem=nnn[KkMm]" in cmdline */
 static int __init setup_mem_sz(char *str)
 {
 	low_mem_sz = memparse(str, NULL) & PAGE_MASK;

 	/* early console might not be setup yet - it will show up later */
 	pr_info("\"mem=%s\": mem sz set to %ldM\n", str, TO_MB(low_mem_sz));

 	return 0;
 }
 early_param("mem", setup_mem_sz);

 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 {
 	int in_use = 0;

 	if (!low_mem_sz) {
 		if (base != low_mem_start)
 			panic("CONFIG_LINUX_LINK_BASE != DT memory { }");

 		low_mem_sz = size;
 		in_use = 1;
 	} else {
 #ifdef CONFIG_HIGHMEM
 		high_mem_start = base;
 		high_mem_sz = size;
 		in_use = 1;
 #endif
 	}

 	pr_info("Memory @ %llx [%lldM] %s\n",
 		base, TO_MB(size), !in_use ? "Not used":"");
 }

 #ifdef CONFIG_BLK_DEV_INITRD
 static int __init early_initrd(char *p)
 {
 	unsigned long start, size;
 	char *endp;

 	start = memparse(p, &endp);
 	if (*endp == ',') {
 		size = memparse(endp + 1, NULL);

 		initrd_start = (unsigned long)__va(start);
 		initrd_end = (unsigned long)__va(start + size);
 	}
 	return 0;
 }
 early_param("initrd", early_initrd);
 #endif

 /*
  * First memory setup routine called from setup_arch()
  * 1. setup swapper's mm @init_mm
  * 2. Count the pages we have and setup bootmem allocator
  * 3. zone setup
  */
 void __init setup_arch_memory(void)
 {
 	unsigned long zones_size[MAX_NR_ZONES];
 	unsigned long zones_holes[MAX_NR_ZONES];

 	init_mm.start_code = (unsigned long)_text;
 	init_mm.end_code = (unsigned long)_etext;
 	init_mm.end_data = (unsigned long)_edata;
 	init_mm.brk = (unsigned long)_end;

 	/* first page of system - kernel .vector starts here */
 	min_low_pfn = ARCH_PFN_OFFSET;

 	/* Last usable page of low mem */
 	max_low_pfn = max_pfn = PFN_DOWN(low_mem_start + low_mem_sz);

 #ifdef CONFIG_FLATMEM
 	/* pfn_valid() uses this */
 	max_mapnr = max_low_pfn - min_low_pfn;
 #endif

 	/*------------- bootmem allocator setup -----------------------*/

 	/*
 	 * seed the bootmem allocator after any DT memory node parsing or
 	 * "mem=xxx" cmdline overrides have potentially updated @arc_mem_sz
 	 *
 	 * Only low mem is added, otherwise we have crashes when allocating
 	 * mem_map[] itself. NO_BOOTMEM allocates mem_map[] at the end of
 	 * avail memory, ending in highmem with a > 32-bit address. However
 	 * it then tries to memset it with a truncaed 32-bit handle, causing
 	 * the crash
 	 */

 	memblock_add_node(low_mem_start, low_mem_sz, 0);
 	memblock_reserve(low_mem_start, __pa(_end) - low_mem_start);

 #ifdef CONFIG_BLK_DEV_INITRD
 	if (initrd_start)
 		memblock_reserve(__pa(initrd_start), initrd_end - initrd_start);
 #endif

 	early_init_fdt_reserve_self();
 	early_init_fdt_scan_reserved_mem();

 	memblock_dump_all();

 	/*----------------- node/zones setup --------------------------*/
 	memset(zones_size, 0, sizeof(zones_size));
 	memset(zones_holes, 0, sizeof(zones_holes));

 	zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn;
 	zones_holes[ZONE_NORMAL] = 0;

 	/*
 	 * We can't use the helper free_area_init(zones[]) because it uses
 	 * PAGE_OFFSET to compute the @min_low_pfn which would be wrong
 	 * when our kernel doesn't start at PAGE_OFFSET, i.e.
 	 * PAGE_OFFSET != CONFIG_LINUX_LINK_BASE
 	 */
 	free_area_init_node(0,			/* node-id */
 			    zones_size,		/* num pages per zone */
 			    min_low_pfn,	/* first pfn of node */
 			    zones_holes);	/* holes */

 #ifdef CONFIG_HIGHMEM
 	/*
 	 * Populate a new node with highmem
 	 *
 	 * On ARC (w/o PAE) HIGHMEM addresses are actually smaller (0 based)
 	 * than addresses in normal ala low memory (0x8000_0000 based).
 	 * Even with PAE, the huge peripheral space hole would waste a lot of
 	 * mem with single mem_map[]. This warrants a mem_map per region design.
 	 * Thus HIGHMEM on ARC is imlemented with DISCONTIGMEM.
 	 *
 	 * DISCONTIGMEM in turns requires multiple nodes. node 0 above is
 	 * populated with normal memory zone while node 1 only has highmem
 	 */
 	node_set_online(1);

 	min_high_pfn = PFN_DOWN(high_mem_start);
 	max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz);

 	zones_size[ZONE_NORMAL] = 0;
 	zones_holes[ZONE_NORMAL] = 0;

 	zones_size[ZONE_HIGHMEM] = max_high_pfn - min_high_pfn;
 	zones_holes[ZONE_HIGHMEM] = 0;

 	free_area_init_node(1,			/* node-id */
 			    zones_size,		/* num pages per zone */
 			    min_high_pfn,	/* first pfn of node */
 			    zones_holes);	/* holes */

 	high_memory = (void *)(min_high_pfn << PAGE_SHIFT);
 	kmap_init();
 #endif
 }

 /*
  * mem_init - initializes memory
  *
  * Frees up bootmem
  * Calculates and displays memory available/used
  */
 void __init mem_init(void)
 {
 #ifdef CONFIG_HIGHMEM
 	unsigned long tmp;

 	reset_all_zones_managed_pages();
 	for (tmp = min_high_pfn; tmp < max_high_pfn; tmp++)
 		free_highmem_page(pfn_to_page(tmp));
 #endif

 	free_all_bootmem();
 	mem_init_print_info(NULL);
 }

 /*
  * free_initmem: Free all the __init memory.
  */
 void __ref free_initmem(void)
 {
 	free_initmem_default(-1);
 }

 #ifdef CONFIG_BLK_DEV_INITRD
 void __init free_initrd_mem(unsigned long start, unsigned long end)
 {
 	free_reserved_area((void *)start, (void *)end, -1, "initrd");
 }
 #endif
	/*
	* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/kernel.h>
	#include <linux/mm.h>
	#include <linux/bootmem.h>
	#include <linux/memblock.h>
	#ifdef CONFIG_BLK_DEV_INITRD
	#include <linux/initrd.h>
	#endif
	#include <linux/of_fdt.h>
	#include <linux/swap.h>
	#include <linux/module.h>
	#include <linux/highmem.h>
	#include <asm/page.h>
	#include <asm/pgalloc.h>
	#include <asm/sections.h>
	#include <asm/arcregs.h>

	pgd_t swapper_pg_dir[PTRS_PER_PGD] __aligned(PAGE_SIZE);
	char empty_zero_page[PAGE_SIZE] __aligned(PAGE_SIZE);
	EXPORT_SYMBOL(empty_zero_page);

	static const unsigned long low_mem_start = CONFIG_LINUX_LINK_BASE;
	static unsigned long low_mem_sz;

	#ifdef CONFIG_HIGHMEM
	static unsigned long min_high_pfn, max_high_pfn;
	static u64 high_mem_start;
	static u64 high_mem_sz;
	#endif

	#ifdef CONFIG_DISCONTIGMEM
	struct pglist_data node_data[MAX_NUMNODES] __read_mostly;
	EXPORT_SYMBOL(node_data);
	#endif

	long __init arc_get_mem_sz(void)
	{
	return low_mem_sz;
	}

	/* User can over-ride above with "mem=nnn[KkMm]" in cmdline */
	static int __init setup_mem_sz(char *str)
	{
	low_mem_sz = memparse(str, NULL) & PAGE_MASK;

	/* early console might not be setup yet - it will show up later */
	pr_info("\"mem=%s\": mem sz set to %ldM\n", str, TO_MB(low_mem_sz));

	return 0;
	}
	early_param("mem", setup_mem_sz);

	void __init early_init_dt_add_memory_arch(u64 base, u64 size)
	{
	int in_use = 0;

	if (!low_mem_sz) {
	if (base != low_mem_start)
	panic("CONFIG_LINUX_LINK_BASE != DT memory { }");

	low_mem_sz = size;
	in_use = 1;
	} else {
	#ifdef CONFIG_HIGHMEM
	high_mem_start = base;
	high_mem_sz = size;
	in_use = 1;
	#endif
	}

	pr_info("Memory @ %llx [%lldM] %s\n",
	base, TO_MB(size), !in_use ? "Not used":"");
	}

	#ifdef CONFIG_BLK_DEV_INITRD
	static int __init early_initrd(char *p)
	{
	unsigned long start, size;
	char *endp;

	start = memparse(p, &endp);
	if (*endp == ',') {
	size = memparse(endp + 1, NULL);

	initrd_start = (unsigned long)__va(start);
	initrd_end = (unsigned long)__va(start + size);
	}
	return 0;
	}
	early_param("initrd", early_initrd);
	#endif

	/*
	* First memory setup routine called from setup_arch()
	* 1. setup swapper's mm @init_mm
	* 2. Count the pages we have and setup bootmem allocator
	* 3. zone setup
	*/
	void __init setup_arch_memory(void)
	{
	unsigned long zones_size[MAX_NR_ZONES];
	unsigned long zones_holes[MAX_NR_ZONES];

	init_mm.start_code = (unsigned long)_text;
	init_mm.end_code = (unsigned long)_etext;
	init_mm.end_data = (unsigned long)_edata;
	init_mm.brk = (unsigned long)_end;

	/* first page of system - kernel .vector starts here */
	min_low_pfn = ARCH_PFN_OFFSET;

	/* Last usable page of low mem */
	max_low_pfn = max_pfn = PFN_DOWN(low_mem_start + low_mem_sz);

	#ifdef CONFIG_FLATMEM
	/* pfn_valid() uses this */
	max_mapnr = max_low_pfn - min_low_pfn;
	#endif

	/------------- bootmem allocator setup -----------------------/

	/*
	* seed the bootmem allocator after any DT memory node parsing or
	* "mem=xxx" cmdline overrides have potentially updated @arc_mem_sz
	*
	* Only low mem is added, otherwise we have crashes when allocating
	* mem_map[] itself. NO_BOOTMEM allocates mem_map[] at the end of
	* avail memory, ending in highmem with a > 32-bit address. However
	* it then tries to memset it with a truncaed 32-bit handle, causing
	* the crash
	*/

	memblock_add_node(low_mem_start, low_mem_sz, 0);
	memblock_reserve(low_mem_start, __pa(_end) - low_mem_start);

	#ifdef CONFIG_BLK_DEV_INITRD
	if (initrd_start)
	memblock_reserve(__pa(initrd_start), initrd_end - initrd_start);
	#endif

	early_init_fdt_reserve_self();
	early_init_fdt_scan_reserved_mem();

	memblock_dump_all();

	/----------------- node/zones setup --------------------------/
	memset(zones_size, 0, sizeof(zones_size));
	memset(zones_holes, 0, sizeof(zones_holes));

	zones_size[ZONE_NORMAL] = max_low_pfn - min_low_pfn;
	zones_holes[ZONE_NORMAL] = 0;

	/*
	* We can't use the helper free_area_init(zones[]) because it uses
	* PAGE_OFFSET to compute the @min_low_pfn which would be wrong
	* when our kernel doesn't start at PAGE_OFFSET, i.e.
	* PAGE_OFFSET != CONFIG_LINUX_LINK_BASE
	*/
	free_area_init_node(0, /* node-id */
	zones_size, /* num pages per zone */
	min_low_pfn, /* first pfn of node */
	zones_holes); /* holes */

	#ifdef CONFIG_HIGHMEM
	/*
	* Populate a new node with highmem
	*
	* On ARC (w/o PAE) HIGHMEM addresses are actually smaller (0 based)
	* than addresses in normal ala low memory (0x8000_0000 based).
	* Even with PAE, the huge peripheral space hole would waste a lot of
	* mem with single mem_map[]. This warrants a mem_map per region design.
	* Thus HIGHMEM on ARC is imlemented with DISCONTIGMEM.
	*
	* DISCONTIGMEM in turns requires multiple nodes. node 0 above is
	* populated with normal memory zone while node 1 only has highmem
	*/
	node_set_online(1);

	min_high_pfn = PFN_DOWN(high_mem_start);
	max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz);

	zones_size[ZONE_NORMAL] = 0;
	zones_holes[ZONE_NORMAL] = 0;

	zones_size[ZONE_HIGHMEM] = max_high_pfn - min_high_pfn;
	zones_holes[ZONE_HIGHMEM] = 0;

	free_area_init_node(1, /* node-id */
	zones_size, /* num pages per zone */
	min_high_pfn, /* first pfn of node */
	zones_holes); /* holes */

	high_memory = (void *)(min_high_pfn << PAGE_SHIFT);
	kmap_init();
	#endif
	}

	/*
	* mem_init - initializes memory
	*
	* Frees up bootmem
	* Calculates and displays memory available/used
	*/
	void __init mem_init(void)
	{
	#ifdef CONFIG_HIGHMEM
	unsigned long tmp;

	reset_all_zones_managed_pages();
	for (tmp = min_high_pfn; tmp < max_high_pfn; tmp++)
	free_highmem_page(pfn_to_page(tmp));
	#endif

	free_all_bootmem();
	mem_init_print_info(NULL);
	}

	/*
	* free_initmem: Free all the __init memory.
	*/
	void __ref free_initmem(void)
	{
	free_initmem_default(-1);
	}

	#ifdef CONFIG_BLK_DEV_INITRD
	void __init free_initrd_mem(unsigned long start, unsigned long end)
	{
	free_reserved_area((void )start, (void )end, -1, "initrd");
	}
	#endif