arch/powerpc/mm/init_32.c - kernel/msm - Gitiles

 /*
  *  PowerPC version
  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  *
  *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
  *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
  *    Copyright (C) 1996 Paul Mackerras
  *  PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
  *
  *  Derived from "arch/i386/mm/init.c"
  *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
  *
  *  This program is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU General Public License
  *  as published by the Free Software Foundation; either version
  *  2 of the License, or (at your option) any later version.
  *
  */

 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/mm.h>
 #include <linux/stddef.h>
 #include <linux/init.h>
 #include <linux/bootmem.h>
 #include <linux/highmem.h>
 #include <linux/initrd.h>
 #include <linux/pagemap.h>

 #include <asm/pgalloc.h>
 #include <asm/prom.h>
 #include <asm/io.h>
 #include <asm/mmu_context.h>
 #include <asm/pgtable.h>
 #include <asm/mmu.h>
 #include <asm/smp.h>
 #include <asm/machdep.h>
 #include <asm/btext.h>
 #include <asm/tlb.h>
 #include <asm/lmb.h>
 #include <asm/sections.h>

 #include "mmu_decl.h"

 #if defined(CONFIG_KERNEL_START_BOOL) || defined(CONFIG_LOWMEM_SIZE_BOOL)
 /* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */
 #if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE))
 #error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL"
 #endif
 #endif
 #define MAX_LOW_MEM	CONFIG_LOWMEM_SIZE

 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

 unsigned long total_memory;
 unsigned long total_lowmem;

 unsigned long ppc_memstart;
 unsigned long ppc_memoffset = PAGE_OFFSET;

 int boot_mapsize;
 #ifdef CONFIG_PPC_PMAC
 unsigned long agp_special_page;
 EXPORT_SYMBOL(agp_special_page);
 #endif

 #ifdef CONFIG_HIGHMEM
 pte_t *kmap_pte;
 pgprot_t kmap_prot;

 EXPORT_SYMBOL(kmap_prot);
 EXPORT_SYMBOL(kmap_pte);
 #endif

 void MMU_init(void);

 /* XXX should be in current.h  -- paulus */
 extern struct task_struct *current_set[NR_CPUS];

 extern int init_bootmem_done;

 /*
  * this tells the system to map all of ram with the segregs
  * (i.e. page tables) instead of the bats.
  * -- Cort
  */
 int __map_without_bats;
 int __map_without_ltlbs;

 /* max amount of low RAM to map in */
 unsigned long __max_low_memory = MAX_LOW_MEM;

 /*
  * limit of what is accessible with initial MMU setup -
  * 256MB usually, but only 16MB on 601.
  */
 unsigned long __initial_memory_limit = 0x10000000;

 /*
  * Check for command-line options that affect what MMU_init will do.
  */
 void MMU_setup(void)
 {
 	/* Check for nobats option (used in mapin_ram). */
 	if (strstr(cmd_line, "nobats")) {
 		__map_without_bats = 1;
 	}

 	if (strstr(cmd_line, "noltlbs")) {
 		__map_without_ltlbs = 1;
 	}
 #ifdef CONFIG_DEBUG_PAGEALLOC
 	__map_without_bats = 1;
 	__map_without_ltlbs = 1;
 #endif
 }

 /*
  * MMU_init sets up the basic memory mappings for the kernel,
  * including both RAM and possibly some I/O regions,
  * and sets up the page tables and the MMU hardware ready to go.
  */
 void __init MMU_init(void)
 {
 	if (ppc_md.progress)
 		ppc_md.progress("MMU:enter", 0x111);

 	/* 601 can only access 16MB at the moment */
 	if (PVR_VER(mfspr(SPRN_PVR)) == 1)
 		__initial_memory_limit = 0x01000000;
 	/* 8xx can only access 8MB at the moment */
 	if (PVR_VER(mfspr(SPRN_PVR)) == 0x50)
 		__initial_memory_limit = 0x00800000;

 	/* parse args from command line */
 	MMU_setup();

 	if (lmb.memory.cnt > 1) {
 		lmb.memory.cnt = 1;
 		lmb_analyze();
 		printk(KERN_WARNING "Only using first contiguous memory region");
 	}

 	total_memory = lmb_end_of_DRAM();
 	total_lowmem = total_memory;

 #ifdef CONFIG_FSL_BOOKE
 	/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
 	 * entries, so we need to adjust lowmem to match the amount we can map
 	 * in the fixed entries */
 	adjust_total_lowmem();
 #endif /* CONFIG_FSL_BOOKE */

 	if (total_lowmem > __max_low_memory) {
 		total_lowmem = __max_low_memory;
 #ifndef CONFIG_HIGHMEM
 		total_memory = total_lowmem;
 		lmb_enforce_memory_limit(total_lowmem);
 		lmb_analyze();
 #endif /* CONFIG_HIGHMEM */
 	}

 	/* Initialize the MMU hardware */
 	if (ppc_md.progress)
 		ppc_md.progress("MMU:hw init", 0x300);
 	MMU_init_hw();

 	/* Map in all of RAM starting at KERNELBASE */
 	if (ppc_md.progress)
 		ppc_md.progress("MMU:mapin", 0x301);
 	mapin_ram();

 #ifdef CONFIG_HIGHMEM
 	ioremap_base = PKMAP_BASE;
 #else
 	ioremap_base = 0xfe000000UL;	/* for now, could be 0xfffff000 */
 #endif /* CONFIG_HIGHMEM */
 	ioremap_bot = ioremap_base;

 	/* Map in I/O resources */
 	if (ppc_md.progress)
 		ppc_md.progress("MMU:setio", 0x302);
 	if (ppc_md.setup_io_mappings)
 		ppc_md.setup_io_mappings();

 	/* Initialize the context management stuff */
 	mmu_context_init();

 	if (ppc_md.progress)
 		ppc_md.progress("MMU:exit", 0x211);

 	/* From now on, btext is no longer BAT mapped if it was at all */
 #ifdef CONFIG_BOOTX_TEXT
 	btext_unmap();
 #endif
 }

 /* This is only called until mem_init is done. */
 void __init *early_get_page(void)
 {
 	void *p;

 	if (init_bootmem_done) {
 		p = alloc_bootmem_pages(PAGE_SIZE);
 	} else {
 		p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE,
 					__initial_memory_limit));
 	}
 	return p;
 }

 /* Free up now-unused memory */
 static void free_sec(unsigned long start, unsigned long end, const char *name)
 {
 	unsigned long cnt = 0;

 	while (start < end) {
 		ClearPageReserved(virt_to_page(start));
 		init_page_count(virt_to_page(start));
 		free_page(start);
 		cnt++;
 		start += PAGE_SIZE;
  	}
 	if (cnt) {
 		printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name);
 		totalram_pages += cnt;
 	}
 }

 void free_initmem(void)
 {
 #define FREESEC(TYPE) \
 	free_sec((unsigned long)(&__ ## TYPE ## _begin), \
 		 (unsigned long)(&__ ## TYPE ## _end), \
 		 #TYPE);

 	printk ("Freeing unused kernel memory:");
 	FREESEC(init);
  	printk("\n");
 	ppc_md.progress = NULL;
 #undef FREESEC
 }

 #ifdef CONFIG_BLK_DEV_INITRD
 void free_initrd_mem(unsigned long start, unsigned long end)
 {
 	if (start < end)
 		printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 	for (; start < end; start += PAGE_SIZE) {
 		ClearPageReserved(virt_to_page(start));
 		init_page_count(virt_to_page(start));
 		free_page(start);
 		totalram_pages++;
 	}
 }
 #endif

 #ifdef CONFIG_PROC_KCORE
 static struct kcore_list kcore_vmem;

 static int __init setup_kcore(void)
 {
 	int i;

 	for (i = 0; i < lmb.memory.cnt; i++) {
 		unsigned long base;
 		unsigned long size;
 		struct kcore_list *kcore_mem;

 		base = lmb.memory.region[i].base;
 		size = lmb.memory.region[i].size;

 		kcore_mem = kmalloc(sizeof(struct kcore_list), GFP_ATOMIC);
 		if (!kcore_mem)
 			panic("%s: kmalloc failed\n", __FUNCTION__);

 		/* must stay under 32 bits */
 		if ( 0xfffffffful - (unsigned long)__va(base) < size) {
 			size = 0xfffffffful - (unsigned long)(__va(base));
 			printk(KERN_DEBUG "setup_kcore: restrict size=%lx\n",
 						size);
 		}

 		kclist_add(kcore_mem, __va(base), size);
 	}

 	kclist_add(&kcore_vmem, (void *)VMALLOC_START,
 		VMALLOC_END-VMALLOC_START);

 	return 0;
 }
 module_init(setup_kcore);
 #endif
	/*
	* PowerPC version
	* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
	*
	* Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
	* and Cort Dougan (PReP) (cort@cs.nmt.edu)
	* Copyright (C) 1996 Paul Mackerras
	* PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
	*
	* Derived from "arch/i386/mm/init.c"
	* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version
	* 2 of the License, or (at your option) any later version.
	*
	*/

	#include <linux/module.h>
	#include <linux/sched.h>
	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/string.h>
	#include <linux/types.h>
	#include <linux/mm.h>
	#include <linux/stddef.h>
	#include <linux/init.h>
	#include <linux/bootmem.h>
	#include <linux/highmem.h>
	#include <linux/initrd.h>
	#include <linux/pagemap.h>

	#include <asm/pgalloc.h>
	#include <asm/prom.h>
	#include <asm/io.h>
	#include <asm/mmu_context.h>
	#include <asm/pgtable.h>
	#include <asm/mmu.h>
	#include <asm/smp.h>
	#include <asm/machdep.h>
	#include <asm/btext.h>
	#include <asm/tlb.h>
	#include <asm/lmb.h>
	#include <asm/sections.h>

	#include "mmu_decl.h"

	#if defined(CONFIG_KERNEL_START_BOOL) \|\| defined(CONFIG_LOWMEM_SIZE_BOOL)
	/* The ammount of lowmem must be within 0xF0000000 - KERNELBASE. */
	#if (CONFIG_LOWMEM_SIZE > (0xF0000000 - KERNELBASE))
	#error "You must adjust CONFIG_LOWMEM_SIZE or CONFIG_START_KERNEL"
	#endif
	#endif
	#define MAX_LOW_MEM CONFIG_LOWMEM_SIZE

	DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

	unsigned long total_memory;
	unsigned long total_lowmem;

	unsigned long ppc_memstart;
	unsigned long ppc_memoffset = PAGE_OFFSET;

	int boot_mapsize;
	#ifdef CONFIG_PPC_PMAC
	unsigned long agp_special_page;
	EXPORT_SYMBOL(agp_special_page);
	#endif

	#ifdef CONFIG_HIGHMEM
	pte_t *kmap_pte;
	pgprot_t kmap_prot;

	EXPORT_SYMBOL(kmap_prot);
	EXPORT_SYMBOL(kmap_pte);
	#endif

	void MMU_init(void);

	/* XXX should be in current.h -- paulus */
	extern struct task_struct *current_set[NR_CPUS];

	extern int init_bootmem_done;

	/*
	* this tells the system to map all of ram with the segregs
	* (i.e. page tables) instead of the bats.
	* -- Cort
	*/
	int __map_without_bats;
	int __map_without_ltlbs;

	/* max amount of low RAM to map in */
	unsigned long __max_low_memory = MAX_LOW_MEM;

	/*
	* limit of what is accessible with initial MMU setup -
	* 256MB usually, but only 16MB on 601.
	*/
	unsigned long __initial_memory_limit = 0x10000000;

	/*
	* Check for command-line options that affect what MMU_init will do.
	*/
	void MMU_setup(void)
	{
	/* Check for nobats option (used in mapin_ram). */
	if (strstr(cmd_line, "nobats")) {
	__map_without_bats = 1;
	}

	if (strstr(cmd_line, "noltlbs")) {
	__map_without_ltlbs = 1;
	}
	#ifdef CONFIG_DEBUG_PAGEALLOC
	__map_without_bats = 1;
	__map_without_ltlbs = 1;
	#endif
	}

	/*
	* MMU_init sets up the basic memory mappings for the kernel,
	* including both RAM and possibly some I/O regions,
	* and sets up the page tables and the MMU hardware ready to go.
	*/
	void __init MMU_init(void)
	{
	if (ppc_md.progress)
	ppc_md.progress("MMU:enter", 0x111);

	/* 601 can only access 16MB at the moment */
	if (PVR_VER(mfspr(SPRN_PVR)) == 1)
	__initial_memory_limit = 0x01000000;
	/* 8xx can only access 8MB at the moment */
	if (PVR_VER(mfspr(SPRN_PVR)) == 0x50)
	__initial_memory_limit = 0x00800000;

	/* parse args from command line */
	MMU_setup();

	if (lmb.memory.cnt > 1) {
	lmb.memory.cnt = 1;
	lmb_analyze();
	printk(KERN_WARNING "Only using first contiguous memory region");
	}

	total_memory = lmb_end_of_DRAM();
	total_lowmem = total_memory;

	#ifdef CONFIG_FSL_BOOKE
	/* Freescale Book-E parts expect lowmem to be mapped by fixed TLB
	* entries, so we need to adjust lowmem to match the amount we can map
	* in the fixed entries */
	adjust_total_lowmem();
	#endif /* CONFIG_FSL_BOOKE */

	if (total_lowmem > __max_low_memory) {
	total_lowmem = __max_low_memory;
	#ifndef CONFIG_HIGHMEM
	total_memory = total_lowmem;
	lmb_enforce_memory_limit(total_lowmem);
	lmb_analyze();
	#endif /* CONFIG_HIGHMEM */
	}

	/* Initialize the MMU hardware */
	if (ppc_md.progress)
	ppc_md.progress("MMU:hw init", 0x300);
	MMU_init_hw();

	/* Map in all of RAM starting at KERNELBASE */
	if (ppc_md.progress)
	ppc_md.progress("MMU:mapin", 0x301);
	mapin_ram();

	#ifdef CONFIG_HIGHMEM
	ioremap_base = PKMAP_BASE;
	#else
	ioremap_base = 0xfe000000UL; /* for now, could be 0xfffff000 */
	#endif /* CONFIG_HIGHMEM */
	ioremap_bot = ioremap_base;

	/* Map in I/O resources */
	if (ppc_md.progress)
	ppc_md.progress("MMU:setio", 0x302);
	if (ppc_md.setup_io_mappings)
	ppc_md.setup_io_mappings();

	/* Initialize the context management stuff */
	mmu_context_init();

	if (ppc_md.progress)
	ppc_md.progress("MMU:exit", 0x211);

	/* From now on, btext is no longer BAT mapped if it was at all */
	#ifdef CONFIG_BOOTX_TEXT
	btext_unmap();
	#endif
	}

	/* This is only called until mem_init is done. */
	void __init *early_get_page(void)
	{
	void *p;

	if (init_bootmem_done) {
	p = alloc_bootmem_pages(PAGE_SIZE);
	} else {
	p = __va(lmb_alloc_base(PAGE_SIZE, PAGE_SIZE,
	__initial_memory_limit));
	}
	return p;
	}

	/* Free up now-unused memory */
	static void free_sec(unsigned long start, unsigned long end, const char *name)
	{
	unsigned long cnt = 0;

	while (start < end) {
	ClearPageReserved(virt_to_page(start));
	init_page_count(virt_to_page(start));
	free_page(start);
	cnt++;
	start += PAGE_SIZE;
	}
	if (cnt) {
	printk(" %ldk %s", cnt << (PAGE_SHIFT - 10), name);
	totalram_pages += cnt;
	}
	}

	void free_initmem(void)
	{
	#define FREESEC(TYPE) \
	free_sec((unsigned long)(&__ ## TYPE ## _begin), \
	(unsigned long)(&__ ## TYPE ## _end), \
	#TYPE);

	printk ("Freeing unused kernel memory:");
	FREESEC(init);
	printk("\n");
	ppc_md.progress = NULL;
	#undef FREESEC
	}

	#ifdef CONFIG_BLK_DEV_INITRD
	void free_initrd_mem(unsigned long start, unsigned long end)
	{
	if (start < end)
	printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
	for (; start < end; start += PAGE_SIZE) {
	ClearPageReserved(virt_to_page(start));
	init_page_count(virt_to_page(start));
	free_page(start);
	totalram_pages++;
	}
	}
	#endif

	#ifdef CONFIG_PROC_KCORE
	static struct kcore_list kcore_vmem;

	static int __init setup_kcore(void)
	{
	int i;

	for (i = 0; i < lmb.memory.cnt; i++) {
	unsigned long base;
	unsigned long size;
	struct kcore_list *kcore_mem;

	base = lmb.memory.region[i].base;
	size = lmb.memory.region[i].size;

	kcore_mem = kmalloc(sizeof(struct kcore_list), GFP_ATOMIC);
	if (!kcore_mem)
	panic("%s: kmalloc failed\n", __FUNCTION__);

	/* must stay under 32 bits */
	if ( 0xfffffffful - (unsigned long)__va(base) < size) {
	size = 0xfffffffful - (unsigned long)(__va(base));
	printk(KERN_DEBUG "setup_kcore: restrict size=%lx\n",
	size);
	}

	kclist_add(kcore_mem, __va(base), size);
	}

	kclist_add(&kcore_vmem, (void *)VMALLOC_START,
	VMALLOC_END-VMALLOC_START);

	return 0;
	}
	module_init(setup_kcore);
	#endif