/*
 * 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) 1995 Linus Torvalds
 * Copyright (C) 1995 Waldorf Electronics
 * Copyright (C) 1994, 95, 96, 97, 98, 99, 2000, 01, 02, 03  Ralf Baechle
 * Copyright (C) 1996 Stoned Elipot
 * Copyright (C) 1999 Silicon Graphics, Inc.
 * Copyright (C) 2000, 2001, 2002, 2007  Maciej W. Rozycki
 */
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/export.h>
#include <linux/screen_info.h>
#include <linux/memblock.h>
#include <linux/bootmem.h>
#include <linux/initrd.h>
#include <linux/root_dev.h>
#include <linux/highmem.h>
#include <linux/console.h>
#include <linux/pfn.h>
#include <linux/debugfs.h>
#include <linux/kexec.h>
#include <linux/sizes.h>

#include <asm/addrspace.h>
#include <asm/bootinfo.h>
#include <asm/bugs.h>
#include <asm/cache.h>
#include <asm/cpu.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/smp-ops.h>
#include <asm/prom.h>

struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;

EXPORT_SYMBOL(cpu_data);

#ifdef CONFIG_VT
struct screen_info screen_info;
#endif

/*
 * Despite it's name this variable is even if we don't have PCI
 */
unsigned int PCI_DMA_BUS_IS_PHYS;

EXPORT_SYMBOL(PCI_DMA_BUS_IS_PHYS);

/*
 * Setup information
 *
 * These are initialized so they are in the .data section
 */
unsigned long mips_machtype __read_mostly = MACH_UNKNOWN;

EXPORT_SYMBOL(mips_machtype);

struct boot_mem_map boot_mem_map;

static char __initdata command_line[COMMAND_LINE_SIZE];
char __initdata arcs_cmdline[COMMAND_LINE_SIZE];

#ifdef CONFIG_CMDLINE_BOOL
static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
#endif

/*
 * mips_io_port_base is the begin of the address space to which x86 style
 * I/O ports are mapped.
 */
const unsigned long mips_io_port_base = -1;
EXPORT_SYMBOL(mips_io_port_base);

static struct resource code_resource = { .name = "Kernel code", };
static struct resource data_resource = { .name = "Kernel data", };

static void *detect_magic __initdata = detect_memory_region;

void __init add_memory_region(phys_t start, phys_t size, long type)
{
        int x = boot_mem_map.nr_map;
        int i;

        /* Sanity check */
        if (start + size < start) {
                pr_warning("Trying to add an invalid memory region, skipped\n");
                return;
        }

        /*
         * Try to merge with existing entry, if any.
         */
        for (i = 0; i < boot_mem_map.nr_map; i++) {
                struct boot_mem_map_entry *entry = boot_mem_map.map + i;
                unsigned long top;

                if (entry->type != type)
                        continue;

                if (start + size < entry->addr)
                        continue;                       /* no overlap */

                if (entry->addr + entry->size < start)
                        continue;                       /* no overlap */

                top = max(entry->addr + entry->size, start + size);
                entry->addr = min(entry->addr, start);
                entry->size = top - entry->addr;

                return;
        }

        if (boot_mem_map.nr_map == BOOT_MEM_MAP_MAX) {
                pr_err("Ooops! Too many entries in the memory map!\n");
                return;
        }

        boot_mem_map.map[x].addr = start;
        boot_mem_map.map[x].size = size;
        boot_mem_map.map[x].type = type;
        boot_mem_map.nr_map++;
}

void __init detect_memory_region(phys_t start, phys_t sz_min, phys_t sz_max)
{
        void *dm = &detect_magic;
        phys_t size;

        for (size = sz_min; size < sz_max; size <<= 1) {
                if (!memcmp(dm, dm + size, sizeof(detect_magic)))
                        break;
        }

        pr_debug("Memory: %lluMB of RAM detected at 0x%llx (min: %lluMB, max: %lluMB)\n",
                ((unsigned long long) size) / SZ_1M,
                (unsigned long long) start,
                ((unsigned long long) sz_min) / SZ_1M,
                ((unsigned long long) sz_max) / SZ_1M);

        add_memory_region(start, size, BOOT_MEM_RAM);
}

static void __init print_memory_map(void)
{
        int i;
        const int field = 2 * sizeof(unsigned long);

        for (i = 0; i < boot_mem_map.nr_map; i++) {
                printk(KERN_INFO " memory: %0*Lx @ %0*Lx ",
                       field, (unsigned long long) boot_mem_map.map[i].size,
                       field, (unsigned long long) boot_mem_map.map[i].addr);

                switch (boot_mem_map.map[i].type) {
                case BOOT_MEM_RAM:
                        printk(KERN_CONT "(usable)\n");
                        break;
                case BOOT_MEM_INIT_RAM:
                        printk(KERN_CONT "(usable after init)\n");
                        break;
                case BOOT_MEM_ROM_DATA:
                        printk(KERN_CONT "(ROM data)\n");
                        break;
                case BOOT_MEM_RESERVED:
                        printk(KERN_CONT "(reserved)\n");
                        break;
                default:
                        printk(KERN_CONT "type %lu\n", boot_mem_map.map[i].type);
                        break;
                }
        }
}

/*
 * Manage initrd
 */
#ifdef CONFIG_BLK_DEV_INITRD

static int __init rd_start_early(char *p)
{
        unsigned long start = memparse(p, &p);

#ifdef CONFIG_64BIT
        /* Guess if the sign extension was forgotten by bootloader */
        if (start < XKPHYS)
                start = (int)start;
#endif
        initrd_start = start;
        initrd_end += start;
        return 0;
}
early_param("rd_start", rd_start_early);

static int __init rd_size_early(char *p)
{
        initrd_end += memparse(p, &p);
        return 0;
}
early_param("rd_size", rd_size_early);

/* it returns the next free pfn after initrd */
static unsigned long __init init_initrd(void)
{
        unsigned long end;

        /*
         * Board specific code or command line parser should have
         * already set up initrd_start and initrd_end. In these cases
         * perfom sanity checks and use them if all looks good.
         */
        if (!initrd_start || initrd_end <= initrd_start)
                goto disable;

        if (initrd_start & ~PAGE_MASK) {
                pr_err("initrd start must be page aligned\n");
                goto disable;
        }
        if (initrd_start < PAGE_OFFSET) {
                pr_err("initrd start < PAGE_OFFSET\n");
                goto disable;
        }

        /*
         * Sanitize initrd addresses. For example firmware
         * can't guess if they need to pass them through
         * 64-bits values if the kernel has been built in pure
         * 32-bit. We need also to switch from KSEG0 to XKPHYS
         * addresses now, so the code can now safely use __pa().
         */
        end = __pa(initrd_end);
        initrd_end = (unsigned long)__va(end);
        initrd_start = (unsigned long)__va(__pa(initrd_start));

        ROOT_DEV = Root_RAM0;
        return PFN_UP(end);
disable:
        initrd_start = 0;
        initrd_end = 0;
        return 0;
}

static void __init finalize_initrd(void)
{
        unsigned long size = initrd_end - initrd_start;

        if (size == 0) {
                printk(KERN_INFO "Initrd not found or empty");
                goto disable;
        }
        if (__pa(initrd_end) > PFN_PHYS(max_low_pfn)) {
                printk(KERN_ERR "Initrd extends beyond end of memory");
                goto disable;
        }

        reserve_bootmem(__pa(initrd_start), size, BOOTMEM_DEFAULT);
        initrd_below_start_ok = 1;

        pr_info("Initial ramdisk at: 0x%lx (%lu bytes)\n",
                initrd_start, size);
        return;
disable:
        printk(KERN_CONT " - disabling initrd\n");
        initrd_start = 0;
        initrd_end = 0;
}

#else  /* !CONFIG_BLK_DEV_INITRD */

static unsigned long __init init_initrd(void)
{
        return 0;
}

#define finalize_initrd()       do {} while (0)

#endif

/*
 * Initialize the bootmem allocator. It also setup initrd related data
 * if needed.
 */
#ifdef CONFIG_SGI_IP27

static void __init bootmem_init(void)
{
        init_initrd();
        finalize_initrd();
}

#else  /* !CONFIG_SGI_IP27 */

static void __init bootmem_init(void)
{
        unsigned long reserved_end;
        unsigned long mapstart = ~0UL;
        unsigned long bootmap_size;
        int i;

        /*
         * Init any data related to initrd. It's a nop if INITRD is
         * not selected. Once that done we can determine the low bound
         * of usable memory.
         */
        reserved_end = max(init_initrd(),
                           (unsigned long) PFN_UP(__pa_symbol(&_end)));

        /*
         * max_low_pfn is not a number of pages. The number of pages
         * of the system is given by 'max_low_pfn - min_low_pfn'.
         */
        min_low_pfn = ~0UL;
        max_low_pfn = 0;

        /*
         * Find the highest page frame number we have available.
         */
        for (i = 0; i < boot_mem_map.nr_map; i++) {
                unsigned long start, end;

                if (boot_mem_map.map[i].type != BOOT_MEM_RAM)
                        continue;

                start = PFN_UP(boot_mem_map.map[i].addr);
                end = PFN_DOWN(boot_mem_map.map[i].addr
                                + boot_mem_map.map[i].size);

                if (end > max_low_pfn)
                        max_low_pfn = end;
                if (start < min_low_pfn)
                        min_low_pfn = start;
                if (end <= reserved_end)
                        continue;
                if (start >= mapstart)
                        continue;
                mapstart = max(reserved_end, start);
        }

        if (min_low_pfn >= max_low_pfn)
                panic("Incorrect memory mapping !!!");
        if (min_low_pfn > ARCH_PFN_OFFSET) {
                pr_info("Wasting %lu bytes for tracking %lu unused pages\n",
                        (min_low_pfn - ARCH_PFN_OFFSET) * sizeof(struct page),
                        min_low_pfn - ARCH_PFN_OFFSET);
        } else if (min_low_pfn < ARCH_PFN_OFFSET) {
                pr_info("%lu free pages won't be used\n",
                        ARCH_PFN_OFFSET - min_low_pfn);
        }
        min_low_pfn = ARCH_PFN_OFFSET;

        /*
         * Determine low and high memory ranges
         */
        max_pfn = max_low_pfn;
        if (max_low_pfn > PFN_DOWN(HIGHMEM_START)) {
#ifdef CONFIG_HIGHMEM
                highstart_pfn = PFN_DOWN(HIGHMEM_START);
                highend_pfn = max_low_pfn;
#endif
                max_low_pfn = PFN_DOWN(HIGHMEM_START);
        }

        /*
         * Initialize the boot-time allocator with low memory only.
         */
        bootmap_size = init_bootmem_node(NODE_DATA(0), mapstart,
                                         min_low_pfn, max_low_pfn);


        for (i = 0; i < boot_mem_map.nr_map; i++) {
                unsigned long start, end;

                start = PFN_UP(boot_mem_map.map[i].addr);
                end = PFN_DOWN(boot_mem_map.map[i].addr
                                + boot_mem_map.map[i].size);

                if (start <= min_low_pfn)
                        start = min_low_pfn;
                if (start >= end)
                        continue;

#ifndef CONFIG_HIGHMEM
                if (end > max_low_pfn)
                        end = max_low_pfn;

                /*
                 * ... finally, is the area going away?
                 */
                if (end <= start)
                        continue;
#endif

                memblock_add_node(PFN_PHYS(start), PFN_PHYS(end - start), 0);
        }

        /*
         * Register fully available low RAM pages with the bootmem allocator.
         */
        for (i = 0; i < boot_mem_map.nr_map; i++) {
                unsigned long start, end, size;

                start = PFN_UP(boot_mem_map.map[i].addr);
                end   = PFN_DOWN(boot_mem_map.map[i].addr
                                    + boot_mem_map.map[i].size);

                /*
                 * Reserve usable memory.
                 */
                switch (boot_mem_map.map[i].type) {
                case BOOT_MEM_RAM:
                        break;
                case BOOT_MEM_INIT_RAM:
                        memory_present(0, start, end);
                        continue;
                default:
                        /* Not usable memory */
                        continue;
                }

                /*
                 * We are rounding up the start address of usable memory
                 * and at the end of the usable range downwards.
                 */
                if (start >= max_low_pfn)
                        continue;
                if (start < reserved_end)
                        start = reserved_end;
                if (end > max_low_pfn)
                        end = max_low_pfn;

                /*
                 * ... finally, is the area going away?
                 */
                if (end <= start)
                        continue;
                size = end - start;

                /* Register lowmem ranges */
                free_bootmem(PFN_PHYS(start), size << PAGE_SHIFT);
                memory_present(0, start, end);
        }

        /*
         * Reserve the bootmap memory.
         */
        reserve_bootmem(PFN_PHYS(mapstart), bootmap_size, BOOTMEM_DEFAULT);

        /*
         * Reserve initrd memory if needed.
         */
        finalize_initrd();
}

#endif  /* CONFIG_SGI_IP27 */

/*
 * arch_mem_init - initialize memory management subsystem
 *
 *  o plat_mem_setup() detects the memory configuration and will record detected
 *    memory areas using add_memory_region.
 *
 * At this stage the memory configuration of the system is known to the
 * kernel but generic memory management system is still entirely uninitialized.
 *
 *  o bootmem_init()
 *  o sparse_init()
 *  o paging_init()
 *
 * At this stage the bootmem allocator is ready to use.
 *
 * NOTE: historically plat_mem_setup did the entire platform initialization.
 *       This was rather impractical because it meant plat_mem_setup had to
 * get away without any kind of memory allocator.  To keep old code from
 * breaking plat_setup was just renamed to plat_setup and a second platform
 * initialization hook for anything else was introduced.
 */

static int usermem __initdata;

static int __init early_parse_mem(char *p)
{
        unsigned long start, size;

        /*
         * If a user specifies memory size, we
         * blow away any automatically generated
         * size.
         */
        if (usermem == 0) {
                boot_mem_map.nr_map = 0;
                usermem = 1;
        }
        start = 0;
        size = memparse(p, &p);
        if (*p == '@')
                start = memparse(p + 1, &p);

        add_memory_region(start, size, BOOT_MEM_RAM);
        return 0;
}
early_param("mem", early_parse_mem);

#ifdef CONFIG_PROC_VMCORE
unsigned long setup_elfcorehdr, setup_elfcorehdr_size;
static int __init early_parse_elfcorehdr(char *p)
{
        int i;

        setup_elfcorehdr = memparse(p, &p);

        for (i = 0; i < boot_mem_map.nr_map; i++) {
                unsigned long start = boot_mem_map.map[i].addr;
                unsigned long end = (boot_mem_map.map[i].addr +
                                     boot_mem_map.map[i].size);
                if (setup_elfcorehdr >= start && setup_elfcorehdr < end) {
                        /*
                         * Reserve from the elf core header to the end of
                         * the memory segment, that should all be kdump
                         * reserved memory.
                         */
                        setup_elfcorehdr_size = end - setup_elfcorehdr;
                        break;
                }
        }
        /*
         * If we don't find it in the memory map, then we shouldn't
         * have to worry about it, as the new kernel won't use it.
         */
        return 0;
}
early_param("elfcorehdr", early_parse_elfcorehdr);
#endif

static void __init arch_mem_addpart(phys_t mem, phys_t end, int type)
{
        phys_t size;
        int i;

        size = end - mem;
        if (!size)
                return;

        /* Make sure it is in the boot_mem_map */
        for (i = 0; i < boot_mem_map.nr_map; i++) {
                if (mem >= boot_mem_map.map[i].addr &&
                    mem < (boot_mem_map.map[i].addr +
                           boot_mem_map.map[i].size))
                        return;
        }
        add_memory_region(mem, size, type);
}

static void __init arch_mem_init(char **cmdline_p)
{
        extern void plat_mem_setup(void);

        /* call board setup routine */
        plat_mem_setup();

        /*
         * Make sure all kernel memory is in the maps.  The "UP" and
         * "DOWN" are opposite for initdata since if it crosses over
         * into another memory section you don't want that to be
         * freed when the initdata is freed.
         */
        arch_mem_addpart(PFN_DOWN(__pa_symbol(&_text)) << PAGE_SHIFT,
                         PFN_UP(__pa_symbol(&_edata)) << PAGE_SHIFT,
                         BOOT_MEM_RAM);
        arch_mem_addpart(PFN_UP(__pa_symbol(&__init_begin)) << PAGE_SHIFT,
                         PFN_DOWN(__pa_symbol(&__init_end)) << PAGE_SHIFT,
                         BOOT_MEM_INIT_RAM);

        pr_info("Determined physical RAM map:\n");
        print_memory_map();

#ifdef CONFIG_CMDLINE_BOOL
#ifdef CONFIG_CMDLINE_OVERRIDE
        strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
#else
        if (builtin_cmdline[0]) {
                strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
                strlcat(arcs_cmdline, builtin_cmdline, COMMAND_LINE_SIZE);
        }
        strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
#endif
#else
        strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
#endif
        strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);

        *cmdline_p = command_line;

        parse_early_param();

        if (usermem) {
                pr_info("User-defined physical RAM map:\n");
                print_memory_map();
        }

        bootmem_init();
#ifdef CONFIG_PROC_VMCORE
        if (setup_elfcorehdr && setup_elfcorehdr_size) {
                printk(KERN_INFO "kdump reserved memory at %lx-%lx\n",
                       setup_elfcorehdr, setup_elfcorehdr_size);
                reserve_bootmem(setup_elfcorehdr, setup_elfcorehdr_size,
                                BOOTMEM_DEFAULT);
        }
#endif
#ifdef CONFIG_KEXEC
        if (crashk_res.start != crashk_res.end)
                reserve_bootmem(crashk_res.start,
                                crashk_res.end - crashk_res.start + 1,
                                BOOTMEM_DEFAULT);
#endif
        device_tree_init();
        sparse_init();
        plat_swiotlb_setup();
        paging_init();
}

#ifdef CONFIG_KEXEC
static inline unsigned long long get_total_mem(void)
{
        unsigned long long total;

        total = max_pfn - min_low_pfn;
        return total << PAGE_SHIFT;
}

static void __init mips_parse_crashkernel(void)
{
        unsigned long long total_mem;
        unsigned long long crash_size, crash_base;
        int ret;

        total_mem = get_total_mem();
        ret = parse_crashkernel(boot_command_line, total_mem,
                                &crash_size, &crash_base);
        if (ret != 0 || crash_size <= 0)
                return;

        crashk_res.start = crash_base;
        crashk_res.end   = crash_base + crash_size - 1;
}

static void __init request_crashkernel(struct resource *res)
{
        int ret;

        ret = request_resource(res, &crashk_res);
        if (!ret)
                pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
                        (unsigned long)((crashk_res.end -
                                crashk_res.start + 1) >> 20),
                        (unsigned long)(crashk_res.start  >> 20));
}
#else /* !defined(CONFIG_KEXEC)  */
static void __init mips_parse_crashkernel(void)
{
}

static void __init request_crashkernel(struct resource *res)
{
}
#endif /* !defined(CONFIG_KEXEC)  */

static void __init resource_init(void)
{
        int i;

        if (UNCAC_BASE != IO_BASE)
                return;

        code_resource.start = __pa_symbol(&_text);
        code_resource.end = __pa_symbol(&_etext) - 1;
        data_resource.start = __pa_symbol(&_etext);
        data_resource.end = __pa_symbol(&_edata) - 1;

        /*
         * Request address space for all standard RAM.
         */
        mips_parse_crashkernel();

        for (i = 0; i < boot_mem_map.nr_map; i++) {
                struct resource *res;
                unsigned long start, end;

                start = boot_mem_map.map[i].addr;
                end = boot_mem_map.map[i].addr + boot_mem_map.map[i].size - 1;
                if (start >= HIGHMEM_START)
                        continue;
                if (end >= HIGHMEM_START)
                        end = HIGHMEM_START - 1;

                res = alloc_bootmem(sizeof(struct resource));
                switch (boot_mem_map.map[i].type) {
                case BOOT_MEM_RAM:
                case BOOT_MEM_INIT_RAM:
                case BOOT_MEM_ROM_DATA:
                        res->name = "System RAM";
                        break;
                case BOOT_MEM_RESERVED:
                default:
                        res->name = "reserved";
                }

                res->start = start;
                res->end = end;

                res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
                request_resource(&iomem_resource, res);

                /*
                 *  We don't know which RAM region contains kernel data,
                 *  so we try it repeatedly and let the resource manager
                 *  test it.
                 */
                request_resource(res, &code_resource);
                request_resource(res, &data_resource);
                request_crashkernel(res);
        }
}

void __init setup_arch(char **cmdline_p)
{
        cpu_probe();
        prom_init();

#ifdef CONFIG_EARLY_PRINTK
        setup_early_printk();
#endif
        cpu_report();
        check_bugs_early();

#if defined(CONFIG_VT)
#if defined(CONFIG_VGA_CONSOLE)
        conswitchp = &vga_con;
#elif defined(CONFIG_DUMMY_CONSOLE)
        conswitchp = &dummy_con;
#endif
#endif

        arch_mem_init(cmdline_p);

        resource_init();
        plat_smp_setup();

        cpu_cache_init();
}

unsigned long kernelsp[NR_CPUS];
unsigned long fw_arg0, fw_arg1, fw_arg2, fw_arg3;

#ifdef CONFIG_DEBUG_FS
struct dentry *mips_debugfs_dir;
static int __init debugfs_mips(void)
{
        struct dentry *d;

        d = debugfs_create_dir("mips", NULL);
        if (!d)
                return -ENOMEM;
        mips_debugfs_dir = d;
        return 0;
}
arch_initcall(debugfs_mips);
#endif