MIPS: Let early memblock_alloc*() allocate memories bottom-up

[mirror_ubuntu-hirsute-kernel.git] / arch / mips / kernel / setup.c

/*
 * 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/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 <linux/device.h>
#include <linux/dma-contiguous.h>
#include <linux/decompress/generic.h>
#include <linux/of_fdt.h>

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

#ifdef CONFIG_MIPS_ELF_APPENDED_DTB
const char __section(.appended_dtb) __appended_dtb[0x100000];
#endif /* CONFIG_MIPS_ELF_APPENDED_DTB */

struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;

EXPORT_SYMBOL(cpu_data);

#ifdef CONFIG_VT
struct screen_info screen_info;
#endif

/*
 * 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 struct resource bss_resource = { .name = "Kernel bss", };

static void *detect_magic __initdata = detect_memory_region;

#ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
unsigned long ARCH_PFN_OFFSET;
EXPORT_SYMBOL(ARCH_PFN_OFFSET);
#endif

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

        /*
         * If the region reaches the top of the physical address space, adjust
         * the size slightly so that (start + size) doesn't overflow
         */
        if (start + size - 1 == PHYS_ADDR_MAX)
                --size;

        /* Sanity check */
        if (start + size < start) {
                pr_warn("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_addr_t start, phys_addr_t sz_min, phys_addr_t sz_max)
{
        void *dm = &detect_magic;
        phys_addr_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 bool __init __maybe_unused memory_region_available(phys_addr_t start,
                                                          phys_addr_t size)
{
        int i;
        bool in_ram = false, free = true;

        for (i = 0; i < boot_mem_map.nr_map; i++) {
                phys_addr_t start_, end_;

                start_ = boot_mem_map.map[i].addr;
                end_ = boot_mem_map.map[i].addr + boot_mem_map.map[i].size;

                switch (boot_mem_map.map[i].type) {
                case BOOT_MEM_RAM:
                        if (start >= start_ && start + size <= end_)
                                in_ram = true;
                        break;
                case BOOT_MEM_RESERVED:
                        if ((start >= start_ && start < end_) ||
                            (start < start_ && start + size >= start_))
                                free = false;
                        break;
                default:
                        continue;
                }
        }

        return in_ram && free;
}

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;
}

/* In some conditions (e.g. big endian bootloader with a little endian
   kernel), the initrd might appear byte swapped.  Try to detect this and
   byte swap it if needed.  */
static void __init maybe_bswap_initrd(void)
{
#if defined(CONFIG_CPU_CAVIUM_OCTEON)
        u64 buf;

        /* Check for CPIO signature */
        if (!memcmp((void *)initrd_start, "070701", 6))
                return;

        /* Check for compressed initrd */
        if (decompress_method((unsigned char *)initrd_start, 8, NULL))
                return;

        /* Try again with a byte swapped header */
        buf = swab64p((u64 *)initrd_start);
        if (!memcmp(&buf, "070701", 6) ||
            decompress_method((unsigned char *)(&buf), 8, NULL)) {
                unsigned long i;

                pr_info("Byteswapped initrd detected\n");
                for (i = initrd_start; i < ALIGN(initrd_end, 8); i += 8)
                        swab64s((u64 *)i);
        }
#endif
}

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;
        }

        maybe_bswap_initrd();

        memblock_reserve(__pa(initrd_start), size);
        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.
 */
#if defined(CONFIG_SGI_IP27) || (defined(CONFIG_CPU_LOONGSON3) && defined(CONFIG_NUMA))

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

#else  /* !CONFIG_SGI_IP27 */

static void __init bootmem_init(void)
{
        unsigned long reserved_end;
        phys_addr_t ramstart = PHYS_ADDR_MAX;
        int i;

        /*
         * Sanity check any INITRD first. We don't take it into account
         * for bootmem setup initially, rely on the end-of-kernel-code
         * as our memory range starting point. Once bootmem is inited we
         * will reserve the area used for the initrd.
         */
        init_initrd();
        reserved_end = (unsigned long) PFN_UP(__pa_symbol(&_end));

        memblock_reserve(PHYS_OFFSET, reserved_end << PAGE_SHIFT);

        /*
         * 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
         * and the lowest used RAM address
         */
        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);

                ramstart = min(ramstart, boot_mem_map.map[i].addr);

#ifndef CONFIG_HIGHMEM
                /*
                 * Skip highmem here so we get an accurate max_low_pfn if low
                 * memory stops short of high memory.
                 * If the region overlaps HIGHMEM_START, end is clipped so
                 * max_pfn excludes the highmem portion.
                 */
                if (start >= PFN_DOWN(HIGHMEM_START))
                        continue;
                if (end > PFN_DOWN(HIGHMEM_START))
                        end = PFN_DOWN(HIGHMEM_START);
#endif

                if (end > max_low_pfn)
                        max_low_pfn = end;
                if (start < min_low_pfn)
                        min_low_pfn = start;
                if (end <= reserved_end)
                        continue;
#ifdef CONFIG_BLK_DEV_INITRD
                /* Skip zones before initrd and initrd itself */
                if (initrd_end && end <= (unsigned long)PFN_UP(__pa(initrd_end)))
                        continue;
#endif
        }

        if (min_low_pfn >= max_low_pfn)
                panic("Incorrect memory mapping !!!");

#ifdef CONFIG_MIPS_AUTO_PFN_OFFSET
        ARCH_PFN_OFFSET = PFN_UP(ramstart);
#else
        /*
         * Reserve any memory between the start of RAM and PHYS_OFFSET
         */
        if (ramstart > PHYS_OFFSET) {
                add_memory_region(PHYS_OFFSET, ramstart - PHYS_OFFSET,
                                  BOOT_MEM_RESERVED);
                memblock_reserve(PHYS_OFFSET, ramstart - PHYS_OFFSET);
        }

        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 (ARCH_PFN_OFFSET - min_low_pfn > 0UL) {
                pr_info("%lu free pages won't be used\n",
                        ARCH_PFN_OFFSET - min_low_pfn);
        }
        min_low_pfn = ARCH_PFN_OFFSET;
#endif

        /*
         * 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);
        }

        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 */
                        if (start > min_low_pfn && end < max_low_pfn)
                                memblock_reserve(boot_mem_map.map[i].addr,
                                                boot_mem_map.map[i].size);

                        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 */
                memory_present(0, start, end);
        }

#ifdef CONFIG_RELOCATABLE
        /*
         * The kernel reserves all memory below its _end symbol as bootmem,
         * but the kernel may now be at a much higher address. The memory
         * between the original and new locations may be returned to the system.
         */
        if (__pa_symbol(_text) > __pa_symbol(VMLINUX_LOAD_ADDRESS)) {
                unsigned long offset;
                extern void show_kernel_relocation(const char *level);

                offset = __pa_symbol(_text) - __pa_symbol(VMLINUX_LOAD_ADDRESS);
                memblock_free(__pa_symbol(VMLINUX_LOAD_ADDRESS), offset);

#if defined(CONFIG_DEBUG_KERNEL) && defined(CONFIG_DEBUG_INFO)
                /*
                 * This information is necessary when debugging the kernel
                 * But is a security vulnerability otherwise!
                 */
                show_kernel_relocation(KERN_INFO);
#endif
        }
#endif

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

#endif  /* CONFIG_SGI_IP27 */

static int usermem __initdata;

static int __init early_parse_mem(char *p)
{
        phys_addr_t 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);

static int __init early_parse_memmap(char *p)
{
        char *oldp;
        u64 start_at, mem_size;

        if (!p)
                return -EINVAL;

        if (!strncmp(p, "exactmap", 8)) {
                pr_err("\"memmap=exactmap\" invalid on MIPS\n");
                return 0;
        }

        oldp = p;
        mem_size = memparse(p, &p);
        if (p == oldp)
                return -EINVAL;

        if (*p == '@') {
                start_at = memparse(p+1, &p);
                add_memory_region(start_at, mem_size, BOOT_MEM_RAM);
        } else if (*p == '#') {
                pr_err("\"memmap=nn#ss\" (force ACPI data) invalid on MIPS\n");
                return -EINVAL;
        } else if (*p == '$') {
                start_at = memparse(p+1, &p);
                add_memory_region(start_at, mem_size, BOOT_MEM_RESERVED);
        } else {
                pr_err("\"memmap\" invalid format!\n");
                return -EINVAL;
        }

        if (*p == '\0') {
                usermem = 1;
                return 0;
        } else
                return -EINVAL;
}
early_param("memmap", early_parse_memmap);

#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_addr_t mem, phys_addr_t end, int type)
{
        phys_addr_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);
}

#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;

        if (!memory_region_available(crash_base, crash_size)) {
                pr_warn("Invalid memory region reserved for crash kernel\n");
                return;
        }

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

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

        if (crashk_res.start == crashk_res.end)
                return;

        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)  */

#define USE_PROM_CMDLINE        IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_BOOTLOADER)
#define USE_DTB_CMDLINE         IS_ENABLED(CONFIG_MIPS_CMDLINE_FROM_DTB)
#define EXTEND_WITH_PROM        IS_ENABLED(CONFIG_MIPS_CMDLINE_DTB_EXTEND)
#define BUILTIN_EXTEND_WITH_PROM        \
        IS_ENABLED(CONFIG_MIPS_CMDLINE_BUILTIN_EXTEND)

/*
 * 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()
 *  o dma_contiguous_reserve()
 *
 * 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_mem_setup and a second platform
 * initialization hook for anything else was introduced.
 */
static void __init arch_mem_init(char **cmdline_p)
{
        struct memblock_region *reg;
        extern void plat_mem_setup(void);

        /*
         * Initialize boot_command_line to an innocuous but non-empty string in
         * order to prevent early_init_dt_scan_chosen() from copying
         * CONFIG_CMDLINE into it without our knowledge. We handle
         * CONFIG_CMDLINE ourselves below & don't want to duplicate its
         * content because repeating arguments can be problematic.
         */
        strlcpy(boot_command_line, " ", COMMAND_LINE_SIZE);

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

        /*
         * 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();

#if defined(CONFIG_CMDLINE_BOOL) && defined(CONFIG_CMDLINE_OVERRIDE)
        strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
#else
        if ((USE_PROM_CMDLINE && arcs_cmdline[0]) ||
            (USE_DTB_CMDLINE && !boot_command_line[0]))
                strlcpy(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);

        if (EXTEND_WITH_PROM && arcs_cmdline[0]) {
                if (boot_command_line[0])
                        strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
                strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
        }

#if defined(CONFIG_CMDLINE_BOOL)
        if (builtin_cmdline[0]) {
                if (boot_command_line[0])
                        strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
                strlcat(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
        }

        if (BUILTIN_EXTEND_WITH_PROM && arcs_cmdline[0]) {
                if (boot_command_line[0])
                        strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
                strlcat(boot_command_line, arcs_cmdline, COMMAND_LINE_SIZE);
        }
#endif
#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();
        }

        early_init_fdt_reserve_self();
        early_init_fdt_scan_reserved_mem();

        bootmem_init();

        /*
         * Prevent memblock from allocating high memory.
         * This cannot be done before max_low_pfn is detected, so up
         * to this point is possible to only reserve physical memory
         * with memblock_reserve; memblock_alloc* can be used
         * only after this point
         */
        memblock_set_current_limit(PFN_PHYS(max_low_pfn));

#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);
                memblock_reserve(setup_elfcorehdr, setup_elfcorehdr_size);
        }
#endif

        mips_parse_crashkernel();
#ifdef CONFIG_KEXEC
        if (crashk_res.start != crashk_res.end)
                memblock_reserve(crashk_res.start,
                                 crashk_res.end - crashk_res.start + 1);
#endif
        device_tree_init();
        sparse_init();
        plat_swiotlb_setup();

        dma_contiguous_reserve(PFN_PHYS(max_low_pfn));
        /* Tell bootmem about cma reserved memblock section */
        for_each_memblock(reserved, reg)
                if (reg->size != 0)
                        memblock_reserve(reg->base, reg->size);

        reserve_bootmem_region(__pa_symbol(&__nosave_begin),
                        __pa_symbol(&__nosave_end)); /* Reserve for hibernation */
}

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;
        bss_resource.start = __pa_symbol(&__bss_start);
        bss_resource.end = __pa_symbol(&__bss_stop) - 1;

        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 = memblock_alloc(sizeof(struct resource), SMP_CACHE_BYTES);

                res->start = start;
                res->end = end;
                res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;

                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";
                        res->flags |= IORESOURCE_SYSRAM;
                        break;
                case BOOT_MEM_RESERVED:
                default:
                        res->name = "reserved";
                }

                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_resource(res, &bss_resource);
                request_crashkernel(res);
        }
}

#ifdef CONFIG_SMP
static void __init prefill_possible_map(void)
{
        int i, possible = num_possible_cpus();

        if (possible > nr_cpu_ids)
                possible = nr_cpu_ids;

        for (i = 0; i < possible; i++)
                set_cpu_possible(i, true);
        for (; i < NR_CPUS; i++)
                set_cpu_possible(i, false);

        nr_cpu_ids = possible;
}
#else
static inline void prefill_possible_map(void) {}
#endif

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

        setup_early_fdc_console();
#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();
        prefill_possible_map();

        cpu_cache_init();
        paging_init();
}

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

#ifdef CONFIG_USE_OF
unsigned long fw_passed_dtb;
#endif

#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

#ifdef CONFIG_DMA_MAYBE_COHERENT
/* User defined DMA coherency from command line. */
enum coherent_io_user_state coherentio = IO_COHERENCE_DEFAULT;
EXPORT_SYMBOL_GPL(coherentio);
int hw_coherentio = 0;  /* Actual hardware supported DMA coherency setting. */

static int __init setcoherentio(char *str)
{
        coherentio = IO_COHERENCE_ENABLED;
        pr_info("Hardware DMA cache coherency (command line)\n");
        return 0;
}
early_param("coherentio", setcoherentio);

static int __init setnocoherentio(char *str)
{
        coherentio = IO_COHERENCE_DISABLED;
        pr_info("Software DMA cache coherency (command line)\n");
        return 0;
}
early_param("nocoherentio", setnocoherentio);
#endif