/*
 *  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
 *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
 *
 *  Derived from "arch/i386/mm/init.c"
 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
 *
 *  Dave Engebretsen <engebret@us.ibm.com>
 *      Rework for PPC64 port.
 *
 *  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/config.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/stddef.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/bootmem.h>
#include <linux/highmem.h>
#include <linux/idr.h>
#include <linux/nodemask.h>
#include <linux/module.h>

#include <asm/pgalloc.h>
#include <asm/page.h>
#include <asm/prom.h>
#include <asm/lmb.h>
#include <asm/rtas.h>
#include <asm/io.h>
#include <asm/mmu_context.h>
#include <asm/pgtable.h>
#include <asm/mmu.h>
#include <asm/uaccess.h>
#include <asm/smp.h>
#include <asm/machdep.h>
#include <asm/tlb.h>
#include <asm/eeh.h>
#include <asm/processor.h>
#include <asm/mmzone.h>
#include <asm/cputable.h>
#include <asm/ppcdebug.h>
#include <asm/sections.h>
#include <asm/system.h>
#include <asm/iommu.h>
#include <asm/abs_addr.h>
#include <asm/vdso.h>
#include <asm/imalloc.h>

#if PGTABLE_RANGE > USER_VSID_RANGE
#warning Limited user VSID range means pagetable space is wasted
#endif

#if (TASK_SIZE_USER64 < PGTABLE_RANGE) && (TASK_SIZE_USER64 < USER_VSID_RANGE)
#warning TASK_SIZE is smaller than it needs to be.
#endif

int mem_init_done;
unsigned long ioremap_bot = IMALLOC_BASE;
static unsigned long phbs_io_bot = PHBS_IO_BASE;

extern pgd_t swapper_pg_dir[];
extern struct task_struct *current_set[NR_CPUS];

unsigned long klimit = (unsigned long)_end;

unsigned long _SDR1=0;
unsigned long _ASR=0;

/* max amount of RAM to use */
unsigned long __max_memory;

/* info on what we think the IO hole is */
unsigned long 	io_hole_start;
unsigned long	io_hole_size;

/*
 * Do very early mm setup.
 */
void __init mm_init_ppc64(void)
{
#ifndef CONFIG_PPC_ISERIES
	unsigned long i;
#endif

	ppc64_boot_msg(0x100, "MM Init");

	/* This is the story of the IO hole... please, keep seated,
	 * unfortunately, we are out of oxygen masks at the moment.
	 * So we need some rough way to tell where your big IO hole
	 * is. On pmac, it's between 2G and 4G, on POWER3, it's around
	 * that area as well, on POWER4 we don't have one, etc...
	 * We need that as a "hint" when sizing the TCE table on POWER3
	 * So far, the simplest way that seem work well enough for us it
	 * to just assume that the first discontinuity in our physical
	 * RAM layout is the IO hole. That may not be correct in the future
	 * (and isn't on iSeries but then we don't care ;)
	 */

#ifndef CONFIG_PPC_ISERIES
	for (i = 1; i < lmb.memory.cnt; i++) {
		unsigned long base, prevbase, prevsize;

		prevbase = lmb.memory.region[i-1].base;
		prevsize = lmb.memory.region[i-1].size;
		base = lmb.memory.region[i].base;
		if (base > (prevbase + prevsize)) {
			io_hole_start = prevbase + prevsize;
			io_hole_size = base  - (prevbase + prevsize);
			break;
		}
	}
#endif /* CONFIG_PPC_ISERIES */
	if (io_hole_start)
		printk("IO Hole assumed to be %lx -> %lx\n",
		       io_hole_start, io_hole_start + io_hole_size - 1);

	ppc64_boot_msg(0x100, "MM Init Done");
}

void free_initmem(void)
{
	unsigned long addr;

	addr = (unsigned long)__init_begin;
	for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
		memset((void *)addr, 0xcc, PAGE_SIZE);
		ClearPageReserved(virt_to_page(addr));
		set_page_count(virt_to_page(addr), 1);
		free_page(addr);
		totalram_pages++;
	}
	printk ("Freeing unused kernel memory: %luk freed\n",
		((unsigned long)__init_end - (unsigned long)__init_begin) >> 10);
}

#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));
		set_page_count(virt_to_page(start), 1);
		free_page(start);
		totalram_pages++;
	}
}
#endif

/*
 * Initialize the bootmem system and give it all the memory we
 * have available.
 */
#ifndef CONFIG_NEED_MULTIPLE_NODES
void __init do_init_bootmem(void)
{
	unsigned long i;
	unsigned long start, bootmap_pages;
	unsigned long total_pages = lmb_end_of_DRAM() >> PAGE_SHIFT;
	int boot_mapsize;

	/*
	 * Find an area to use for the bootmem bitmap.  Calculate the size of
	 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE.
	 * Add 1 additional page in case the address isn't page-aligned.
	 */
	bootmap_pages = bootmem_bootmap_pages(total_pages);

	start = lmb_alloc(bootmap_pages<<PAGE_SHIFT, PAGE_SIZE);
	BUG_ON(!start);

	boot_mapsize = init_bootmem(start >> PAGE_SHIFT, total_pages);

	max_pfn = max_low_pfn;

	/* Add all physical memory to the bootmem map, mark each area
	 * present.
	 */
	for (i=0; i < lmb.memory.cnt; i++)
		free_bootmem(lmb.memory.region[i].base,
			     lmb_size_bytes(&lmb.memory, i));

	/* reserve the sections we're already using */
	for (i=0; i < lmb.reserved.cnt; i++)
		reserve_bootmem(lmb.reserved.region[i].base,
				lmb_size_bytes(&lmb.reserved, i));

	for (i=0; i < lmb.memory.cnt; i++)
		memory_present(0, lmb_start_pfn(&lmb.memory, i),
			       lmb_end_pfn(&lmb.memory, i));
}

/*
 * paging_init() sets up the page tables - in fact we've already done this.
 */
void __init paging_init(void)
{
	unsigned long zones_size[MAX_NR_ZONES];
	unsigned long zholes_size[MAX_NR_ZONES];
	unsigned long total_ram = lmb_phys_mem_size();
	unsigned long top_of_ram = lmb_end_of_DRAM();

	printk(KERN_INFO "Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
	       top_of_ram, total_ram);
	printk(KERN_INFO "Memory hole size: %ldMB\n",
	       (top_of_ram - total_ram) >> 20);
	/*
	 * All pages are DMA-able so we put them all in the DMA zone.
	 */
	memset(zones_size, 0, sizeof(zones_size));
	memset(zholes_size, 0, sizeof(zholes_size));

	zones_size[ZONE_DMA] = top_of_ram >> PAGE_SHIFT;
	zholes_size[ZONE_DMA] = (top_of_ram - total_ram) >> PAGE_SHIFT;

	free_area_init_node(0, NODE_DATA(0), zones_size,
			    __pa(PAGE_OFFSET) >> PAGE_SHIFT, zholes_size);
}
#endif /* ! CONFIG_NEED_MULTIPLE_NODES */

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, size;
		struct kcore_list *kcore_mem;

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

		/* GFP_ATOMIC to avoid might_sleep warnings during boot */
		kcore_mem = kmalloc(sizeof(struct kcore_list), GFP_ATOMIC);
		if (!kcore_mem)
			panic("mem_init: kmalloc failed\n");

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

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

	return 0;
}
module_init(setup_kcore);

void __init mem_init(void)
{
#ifdef CONFIG_NEED_MULTIPLE_NODES
	int nid;
#endif
	pg_data_t *pgdat;
	unsigned long i;
	struct page *page;
	unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize;

	num_physpages = max_low_pfn;	/* RAM is assumed contiguous */
	high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);

#ifdef CONFIG_NEED_MULTIPLE_NODES
        for_each_online_node(nid) {
		if (NODE_DATA(nid)->node_spanned_pages != 0) {
			printk("freeing bootmem node %x\n", nid);
			totalram_pages +=
				free_all_bootmem_node(NODE_DATA(nid));
		}
	}
#else
	max_mapnr = num_physpages;
	totalram_pages += free_all_bootmem();
#endif

	for_each_pgdat(pgdat) {
		for (i = 0; i < pgdat->node_spanned_pages; i++) {
			page = pgdat_page_nr(pgdat, i);
			if (PageReserved(page))
				reservedpages++;
		}
	}

	codesize = (unsigned long)&_etext - (unsigned long)&_stext;
	initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin;
	datasize = (unsigned long)&_edata - (unsigned long)&__init_end;
	bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start;

	printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, "
	       "%luk reserved, %luk data, %luk bss, %luk init)\n",
		(unsigned long)nr_free_pages() << (PAGE_SHIFT-10),
		num_physpages << (PAGE_SHIFT-10),
		codesize >> 10,
		reservedpages << (PAGE_SHIFT-10),
		datasize >> 10,
		bsssize >> 10,
		initsize >> 10);

	mem_init_done = 1;

	/* Initialize the vDSO */
	vdso_init();
}

void __iomem * reserve_phb_iospace(unsigned long size)
{
	void __iomem *virt_addr;
		
	if (phbs_io_bot >= IMALLOC_BASE) 
		panic("reserve_phb_iospace(): phb io space overflow\n");
			
	virt_addr = (void __iomem *) phbs_io_bot;
	phbs_io_bot += size;

	return virt_addr;
}

static void zero_ctor(void *addr, kmem_cache_t *cache, unsigned long flags)
{
	memset(addr, 0, kmem_cache_size(cache));
}

static const int pgtable_cache_size[2] = {
	PTE_TABLE_SIZE, PMD_TABLE_SIZE
};
static const char *pgtable_cache_name[ARRAY_SIZE(pgtable_cache_size)] = {
	"pgd_pte_cache", "pud_pmd_cache",
};

kmem_cache_t *pgtable_cache[ARRAY_SIZE(pgtable_cache_size)];

void pgtable_cache_init(void)
{
	int i;

	BUILD_BUG_ON(PTE_TABLE_SIZE != pgtable_cache_size[PTE_CACHE_NUM]);
	BUILD_BUG_ON(PMD_TABLE_SIZE != pgtable_cache_size[PMD_CACHE_NUM]);
	BUILD_BUG_ON(PUD_TABLE_SIZE != pgtable_cache_size[PUD_CACHE_NUM]);
	BUILD_BUG_ON(PGD_TABLE_SIZE != pgtable_cache_size[PGD_CACHE_NUM]);

	for (i = 0; i < ARRAY_SIZE(pgtable_cache_size); i++) {
		int size = pgtable_cache_size[i];
		const char *name = pgtable_cache_name[i];

		pgtable_cache[i] = kmem_cache_create(name,
						     size, size,
						     SLAB_HWCACHE_ALIGN
						     | SLAB_MUST_HWCACHE_ALIGN,
						     zero_ctor,
						     NULL);
		if (! pgtable_cache[i])
			panic("pgtable_cache_init(): could not create %s!\n",
			      name);
	}
}

pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr,
			      unsigned long size, pgprot_t vma_prot)
{
	if (ppc_md.phys_mem_access_prot)
		return ppc_md.phys_mem_access_prot(file, addr, size, vma_prot);

	if (!page_is_ram(addr >> PAGE_SHIFT))
		vma_prot = __pgprot(pgprot_val(vma_prot)
				    | _PAGE_GUARDED | _PAGE_NO_CACHE);
	return vma_prot;
}
EXPORT_SYMBOL(phys_mem_access_prot);