mm: fix exec activate_mm vs TLB shootdown and lazy tlb switching race

[linux/fpc-iii.git] / arch / ia64 / kernel / setup.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Architecture-specific setup.
 *
 * Copyright (C) 1998-2001, 2003-2004 Hewlett-Packard Co
 *      David Mosberger-Tang <davidm@hpl.hp.com>
 *      Stephane Eranian <eranian@hpl.hp.com>
 * Copyright (C) 2000, 2004 Intel Corp
 *      Rohit Seth <rohit.seth@intel.com>
 *      Suresh Siddha <suresh.b.siddha@intel.com>
 *      Gordon Jin <gordon.jin@intel.com>
 * Copyright (C) 1999 VA Linux Systems
 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
 *
 * 12/26/04 S.Siddha, G.Jin, R.Seth
 *                      Add multi-threading and multi-core detection
 * 11/12/01 D.Mosberger Convert get_cpuinfo() to seq_file based show_cpuinfo().
 * 04/04/00 D.Mosberger renamed cpu_initialized to cpu_online_map
 * 03/31/00 R.Seth      cpu_initialized and current->processor fixes
 * 02/04/00 D.Mosberger some more get_cpuinfo fixes...
 * 02/01/00 R.Seth      fixed get_cpuinfo for SMP
 * 01/07/99 S.Eranian   added the support for command line argument
 * 06/24/99 W.Drummond  added boot_cpu_data.
 * 05/28/05 Z. Menyhart Dynamic stride size for "flush_icache_range()"
 */
#include <linux/module.h>
#include <linux/init.h>

#include <linux/acpi.h>
#include <linux/bootmem.h>
#include <linux/console.h>
#include <linux/delay.h>
#include <linux/cpu.h>
#include <linux/kernel.h>
#include <linux/reboot.h>
#include <linux/sched/mm.h>
#include <linux/sched/clock.h>
#include <linux/sched/task_stack.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/threads.h>
#include <linux/screen_info.h>
#include <linux/dmi.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/efi.h>
#include <linux/initrd.h>
#include <linux/pm.h>
#include <linux/cpufreq.h>
#include <linux/kexec.h>
#include <linux/crash_dump.h>

#include <asm/machvec.h>
#include <asm/mca.h>
#include <asm/meminit.h>
#include <asm/page.h>
#include <asm/patch.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/sal.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/smp.h>
#include <asm/tlbflush.h>
#include <asm/unistd.h>
#include <asm/hpsim.h>

#if defined(CONFIG_SMP) && (IA64_CPU_SIZE > PAGE_SIZE)
# error "struct cpuinfo_ia64 too big!"
#endif

#ifdef CONFIG_SMP
unsigned long __per_cpu_offset[NR_CPUS];
EXPORT_SYMBOL(__per_cpu_offset);
#endif

DEFINE_PER_CPU(struct cpuinfo_ia64, ia64_cpu_info);
EXPORT_SYMBOL(ia64_cpu_info);
DEFINE_PER_CPU(unsigned long, local_per_cpu_offset);
#ifdef CONFIG_SMP
EXPORT_SYMBOL(local_per_cpu_offset);
#endif
unsigned long ia64_cycles_per_usec;
struct ia64_boot_param *ia64_boot_param;
struct screen_info screen_info;
unsigned long vga_console_iobase;
unsigned long vga_console_membase;

static struct resource data_resource = {
        .name   = "Kernel data",
        .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
};

static struct resource code_resource = {
        .name   = "Kernel code",
        .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
};

static struct resource bss_resource = {
        .name   = "Kernel bss",
        .flags  = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
};

unsigned long ia64_max_cacheline_size;

unsigned long ia64_iobase;      /* virtual address for I/O accesses */
EXPORT_SYMBOL(ia64_iobase);
struct io_space io_space[MAX_IO_SPACES];
EXPORT_SYMBOL(io_space);
unsigned int num_io_spaces;

/*
 * "flush_icache_range()" needs to know what processor dependent stride size to use
 * when it makes i-cache(s) coherent with d-caches.
 */
#define I_CACHE_STRIDE_SHIFT    5       /* Safest way to go: 32 bytes by 32 bytes */
unsigned long ia64_i_cache_stride_shift = ~0;
/*
 * "clflush_cache_range()" needs to know what processor dependent stride size to
 * use when it flushes cache lines including both d-cache and i-cache.
 */
/* Safest way to go: 32 bytes by 32 bytes */
#define CACHE_STRIDE_SHIFT      5
unsigned long ia64_cache_stride_shift = ~0;

/*
 * The merge_mask variable needs to be set to (max(iommu_page_size(iommu)) - 1).  This
 * mask specifies a mask of address bits that must be 0 in order for two buffers to be
 * mergeable by the I/O MMU (i.e., the end address of the first buffer and the start
 * address of the second buffer must be aligned to (merge_mask+1) in order to be
 * mergeable).  By default, we assume there is no I/O MMU which can merge physically
 * discontiguous buffers, so we set the merge_mask to ~0UL, which corresponds to a iommu
 * page-size of 2^64.
 */
unsigned long ia64_max_iommu_merge_mask = ~0UL;
EXPORT_SYMBOL(ia64_max_iommu_merge_mask);

/*
 * We use a special marker for the end of memory and it uses the extra (+1) slot
 */
struct rsvd_region rsvd_region[IA64_MAX_RSVD_REGIONS + 1] __initdata;
int num_rsvd_regions __initdata;


/*
 * Filter incoming memory segments based on the primitive map created from the boot
 * parameters. Segments contained in the map are removed from the memory ranges. A
 * caller-specified function is called with the memory ranges that remain after filtering.
 * This routine does not assume the incoming segments are sorted.
 */
int __init
filter_rsvd_memory (u64 start, u64 end, void *arg)
{
        u64 range_start, range_end, prev_start;
        void (*func)(unsigned long, unsigned long, int);
        int i;

#if IGNORE_PFN0
        if (start == PAGE_OFFSET) {
                printk(KERN_WARNING "warning: skipping physical page 0\n");
                start += PAGE_SIZE;
                if (start >= end) return 0;
        }
#endif
        /*
         * lowest possible address(walker uses virtual)
         */
        prev_start = PAGE_OFFSET;
        func = arg;

        for (i = 0; i < num_rsvd_regions; ++i) {
                range_start = max(start, prev_start);
                range_end   = min(end, rsvd_region[i].start);

                if (range_start < range_end)
                        call_pernode_memory(__pa(range_start), range_end - range_start, func);

                /* nothing more available in this segment */
                if (range_end == end) return 0;

                prev_start = rsvd_region[i].end;
        }
        /* end of memory marker allows full processing inside loop body */
        return 0;
}

/*
 * Similar to "filter_rsvd_memory()", but the reserved memory ranges
 * are not filtered out.
 */
int __init
filter_memory(u64 start, u64 end, void *arg)
{
        void (*func)(unsigned long, unsigned long, int);

#if IGNORE_PFN0
        if (start == PAGE_OFFSET) {
                printk(KERN_WARNING "warning: skipping physical page 0\n");
                start += PAGE_SIZE;
                if (start >= end)
                        return 0;
        }
#endif
        func = arg;
        if (start < end)
                call_pernode_memory(__pa(start), end - start, func);
        return 0;
}

static void __init
sort_regions (struct rsvd_region *rsvd_region, int max)
{
        int j;

        /* simple bubble sorting */
        while (max--) {
                for (j = 0; j < max; ++j) {
                        if (rsvd_region[j].start > rsvd_region[j+1].start) {
                                struct rsvd_region tmp;
                                tmp = rsvd_region[j];
                                rsvd_region[j] = rsvd_region[j + 1];
                                rsvd_region[j + 1] = tmp;
                        }
                }
        }
}

/* merge overlaps */
static int __init
merge_regions (struct rsvd_region *rsvd_region, int max)
{
        int i;
        for (i = 1; i < max; ++i) {
                if (rsvd_region[i].start >= rsvd_region[i-1].end)
                        continue;
                if (rsvd_region[i].end > rsvd_region[i-1].end)
                        rsvd_region[i-1].end = rsvd_region[i].end;
                --max;
                memmove(&rsvd_region[i], &rsvd_region[i+1],
                        (max - i) * sizeof(struct rsvd_region));
        }
        return max;
}

/*
 * Request address space for all standard resources
 */
static int __init register_memory(void)
{
        code_resource.start = ia64_tpa(_text);
        code_resource.end   = ia64_tpa(_etext) - 1;
        data_resource.start = ia64_tpa(_etext);
        data_resource.end   = ia64_tpa(_edata) - 1;
        bss_resource.start  = ia64_tpa(__bss_start);
        bss_resource.end    = ia64_tpa(_end) - 1;
        efi_initialize_iomem_resources(&code_resource, &data_resource,
                        &bss_resource);

        return 0;
}

__initcall(register_memory);


#ifdef CONFIG_KEXEC

/*
 * This function checks if the reserved crashkernel is allowed on the specific
 * IA64 machine flavour. Machines without an IO TLB use swiotlb and require
 * some memory below 4 GB (i.e. in 32 bit area), see the implementation of
 * lib/swiotlb.c. The hpzx1 architecture has an IO TLB but cannot use that
 * in kdump case. See the comment in sba_init() in sba_iommu.c.
 *
 * So, the only machvec that really supports loading the kdump kernel
 * over 4 GB is "sn2".
 */
static int __init check_crashkernel_memory(unsigned long pbase, size_t size)
{
        if (ia64_platform_is("sn2") || ia64_platform_is("uv"))
                return 1;
        else
                return pbase < (1UL << 32);
}

static void __init setup_crashkernel(unsigned long total, int *n)
{
        unsigned long long base = 0, size = 0;
        int ret;

        ret = parse_crashkernel(boot_command_line, total,
                        &size, &base);
        if (ret == 0 && size > 0) {
                if (!base) {
                        sort_regions(rsvd_region, *n);
                        *n = merge_regions(rsvd_region, *n);
                        base = kdump_find_rsvd_region(size,
                                        rsvd_region, *n);
                }

                if (!check_crashkernel_memory(base, size)) {
                        pr_warning("crashkernel: There would be kdump memory "
                                "at %ld GB but this is unusable because it "
                                "must\nbe below 4 GB. Change the memory "
                                "configuration of the machine.\n",
                                (unsigned long)(base >> 30));
                        return;
                }

                if (base != ~0UL) {
                        printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
                                        "for crashkernel (System RAM: %ldMB)\n",
                                        (unsigned long)(size >> 20),
                                        (unsigned long)(base >> 20),
                                        (unsigned long)(total >> 20));
                        rsvd_region[*n].start =
                                (unsigned long)__va(base);
                        rsvd_region[*n].end =
                                (unsigned long)__va(base + size);
                        (*n)++;
                        crashk_res.start = base;
                        crashk_res.end = base + size - 1;
                }
        }
        efi_memmap_res.start = ia64_boot_param->efi_memmap;
        efi_memmap_res.end = efi_memmap_res.start +
                ia64_boot_param->efi_memmap_size;
        boot_param_res.start = __pa(ia64_boot_param);
        boot_param_res.end = boot_param_res.start +
                sizeof(*ia64_boot_param);
}
#else
static inline void __init setup_crashkernel(unsigned long total, int *n)
{}
#endif

/**
 * reserve_memory - setup reserved memory areas
 *
 * Setup the reserved memory areas set aside for the boot parameters,
 * initrd, etc.  There are currently %IA64_MAX_RSVD_REGIONS defined,
 * see arch/ia64/include/asm/meminit.h if you need to define more.
 */
void __init
reserve_memory (void)
{
        int n = 0;
        unsigned long total_memory;

        /*
         * none of the entries in this table overlap
         */
        rsvd_region[n].start = (unsigned long) ia64_boot_param;
        rsvd_region[n].end   = rsvd_region[n].start + sizeof(*ia64_boot_param);
        n++;

        rsvd_region[n].start = (unsigned long) __va(ia64_boot_param->efi_memmap);
        rsvd_region[n].end   = rsvd_region[n].start + ia64_boot_param->efi_memmap_size;
        n++;

        rsvd_region[n].start = (unsigned long) __va(ia64_boot_param->command_line);
        rsvd_region[n].end   = (rsvd_region[n].start
                                + strlen(__va(ia64_boot_param->command_line)) + 1);
        n++;

        rsvd_region[n].start = (unsigned long) ia64_imva((void *)KERNEL_START);
        rsvd_region[n].end   = (unsigned long) ia64_imva(_end);
        n++;

#ifdef CONFIG_BLK_DEV_INITRD
        if (ia64_boot_param->initrd_start) {
                rsvd_region[n].start = (unsigned long)__va(ia64_boot_param->initrd_start);
                rsvd_region[n].end   = rsvd_region[n].start + ia64_boot_param->initrd_size;
                n++;
        }
#endif

#ifdef CONFIG_CRASH_DUMP
        if (reserve_elfcorehdr(&rsvd_region[n].start,
                               &rsvd_region[n].end) == 0)
                n++;
#endif

        total_memory = efi_memmap_init(&rsvd_region[n].start, &rsvd_region[n].end);
        n++;

        setup_crashkernel(total_memory, &n);

        /* end of memory marker */
        rsvd_region[n].start = ~0UL;
        rsvd_region[n].end   = ~0UL;
        n++;

        num_rsvd_regions = n;
        BUG_ON(IA64_MAX_RSVD_REGIONS + 1 < n);

        sort_regions(rsvd_region, num_rsvd_regions);
        num_rsvd_regions = merge_regions(rsvd_region, num_rsvd_regions);
}


/**
 * find_initrd - get initrd parameters from the boot parameter structure
 *
 * Grab the initrd start and end from the boot parameter struct given us by
 * the boot loader.
 */
void __init
find_initrd (void)
{
#ifdef CONFIG_BLK_DEV_INITRD
        if (ia64_boot_param->initrd_start) {
                initrd_start = (unsigned long)__va(ia64_boot_param->initrd_start);
                initrd_end   = initrd_start+ia64_boot_param->initrd_size;

                printk(KERN_INFO "Initial ramdisk at: 0x%lx (%llu bytes)\n",
                       initrd_start, ia64_boot_param->initrd_size);
        }
#endif
}

static void __init
io_port_init (void)
{
        unsigned long phys_iobase;

        /*
         * Set `iobase' based on the EFI memory map or, failing that, the
         * value firmware left in ar.k0.
         *
         * Note that in ia32 mode, IN/OUT instructions use ar.k0 to compute
         * the port's virtual address, so ia32_load_state() loads it with a
         * user virtual address.  But in ia64 mode, glibc uses the
         * *physical* address in ar.k0 to mmap the appropriate area from
         * /dev/mem, and the inX()/outX() interfaces use MMIO.  In both
         * cases, user-mode can only use the legacy 0-64K I/O port space.
         *
         * ar.k0 is not involved in kernel I/O port accesses, which can use
         * any of the I/O port spaces and are done via MMIO using the
         * virtual mmio_base from the appropriate io_space[].
         */
        phys_iobase = efi_get_iobase();
        if (!phys_iobase) {
                phys_iobase = ia64_get_kr(IA64_KR_IO_BASE);
                printk(KERN_INFO "No I/O port range found in EFI memory map, "
                        "falling back to AR.KR0 (0x%lx)\n", phys_iobase);
        }
        ia64_iobase = (unsigned long) ioremap(phys_iobase, 0);
        ia64_set_kr(IA64_KR_IO_BASE, __pa(ia64_iobase));

        /* setup legacy IO port space */
        io_space[0].mmio_base = ia64_iobase;
        io_space[0].sparse = 1;
        num_io_spaces = 1;
}

/**
 * early_console_setup - setup debugging console
 *
 * Consoles started here require little enough setup that we can start using
 * them very early in the boot process, either right after the machine
 * vector initialization, or even before if the drivers can detect their hw.
 *
 * Returns non-zero if a console couldn't be setup.
 */
static inline int __init
early_console_setup (char *cmdline)
{
        int earlycons = 0;

#ifdef CONFIG_SERIAL_SGI_L1_CONSOLE
        {
                extern int sn_serial_console_early_setup(void);
                if (!sn_serial_console_early_setup())
                        earlycons++;
        }
#endif
#ifdef CONFIG_EFI_PCDP
        if (!efi_setup_pcdp_console(cmdline))
                earlycons++;
#endif
        if (!simcons_register())
                earlycons++;

        return (earlycons) ? 0 : -1;
}

static inline void
mark_bsp_online (void)
{
#ifdef CONFIG_SMP
        /* If we register an early console, allow CPU 0 to printk */
        set_cpu_online(smp_processor_id(), true);
#endif
}

static __initdata int nomca;
static __init int setup_nomca(char *s)
{
        nomca = 1;
        return 0;
}
early_param("nomca", setup_nomca);

#ifdef CONFIG_CRASH_DUMP
int __init reserve_elfcorehdr(u64 *start, u64 *end)
{
        u64 length;

        /* We get the address using the kernel command line,
         * but the size is extracted from the EFI tables.
         * Both address and size are required for reservation
         * to work properly.
         */

        if (!is_vmcore_usable())
                return -EINVAL;

        if ((length = vmcore_find_descriptor_size(elfcorehdr_addr)) == 0) {
                vmcore_unusable();
                return -EINVAL;
        }

        *start = (unsigned long)__va(elfcorehdr_addr);
        *end = *start + length;
        return 0;
}

#endif /* CONFIG_PROC_VMCORE */

void __init
setup_arch (char **cmdline_p)
{
        unw_init();

        ia64_patch_vtop((u64) __start___vtop_patchlist, (u64) __end___vtop_patchlist);

        *cmdline_p = __va(ia64_boot_param->command_line);
        strlcpy(boot_command_line, *cmdline_p, COMMAND_LINE_SIZE);

        efi_init();
        io_port_init();

#ifdef CONFIG_IA64_GENERIC
        /* machvec needs to be parsed from the command line
         * before parse_early_param() is called to ensure
         * that ia64_mv is initialised before any command line
         * settings may cause console setup to occur
         */
        machvec_init_from_cmdline(*cmdline_p);
#endif

        parse_early_param();

        if (early_console_setup(*cmdline_p) == 0)
                mark_bsp_online();

#ifdef CONFIG_ACPI
        /* Initialize the ACPI boot-time table parser */
        acpi_table_init();
        early_acpi_boot_init();
# ifdef CONFIG_ACPI_NUMA
        acpi_numa_init();
        acpi_numa_fixup();
#  ifdef CONFIG_ACPI_HOTPLUG_CPU
        prefill_possible_map();
#  endif
        per_cpu_scan_finalize((cpumask_weight(&early_cpu_possible_map) == 0 ?
                32 : cpumask_weight(&early_cpu_possible_map)),
                additional_cpus > 0 ? additional_cpus : 0);
# endif
#endif /* CONFIG_APCI_BOOT */

#ifdef CONFIG_SMP
        smp_build_cpu_map();
#endif
        find_memory();

        /* process SAL system table: */
        ia64_sal_init(__va(efi.sal_systab));

#ifdef CONFIG_ITANIUM
        ia64_patch_rse((u64) __start___rse_patchlist, (u64) __end___rse_patchlist);
#else
        {
                unsigned long num_phys_stacked;

                if (ia64_pal_rse_info(&num_phys_stacked, 0) == 0 && num_phys_stacked > 96)
                        ia64_patch_rse((u64) __start___rse_patchlist, (u64) __end___rse_patchlist);
        }
#endif

#ifdef CONFIG_SMP
        cpu_physical_id(0) = hard_smp_processor_id();
#endif

        cpu_init();     /* initialize the bootstrap CPU */
        mmu_context_init();     /* initialize context_id bitmap */

#ifdef CONFIG_VT
        if (!conswitchp) {
# if defined(CONFIG_DUMMY_CONSOLE)
                conswitchp = &dummy_con;
# endif
# if defined(CONFIG_VGA_CONSOLE)
                /*
                 * Non-legacy systems may route legacy VGA MMIO range to system
                 * memory.  vga_con probes the MMIO hole, so memory looks like
                 * a VGA device to it.  The EFI memory map can tell us if it's
                 * memory so we can avoid this problem.
                 */
                if (efi_mem_type(0xA0000) != EFI_CONVENTIONAL_MEMORY)
                        conswitchp = &vga_con;
# endif
        }
#endif

        /* enable IA-64 Machine Check Abort Handling unless disabled */
        if (!nomca)
                ia64_mca_init();

        platform_setup(cmdline_p);
#ifndef CONFIG_IA64_HP_SIM
        check_sal_cache_flush();
#endif
        paging_init();

        clear_sched_clock_stable();
}

/*
 * Display cpu info for all CPUs.
 */
static int
show_cpuinfo (struct seq_file *m, void *v)
{
#ifdef CONFIG_SMP
#       define lpj      c->loops_per_jiffy
#       define cpunum   c->cpu
#else
#       define lpj      loops_per_jiffy
#       define cpunum   0
#endif
        static struct {
                unsigned long mask;
                const char *feature_name;
        } feature_bits[] = {
                { 1UL << 0, "branchlong" },
                { 1UL << 1, "spontaneous deferral"},
                { 1UL << 2, "16-byte atomic ops" }
        };
        char features[128], *cp, *sep;
        struct cpuinfo_ia64 *c = v;
        unsigned long mask;
        unsigned long proc_freq;
        int i, size;

        mask = c->features;

        /* build the feature string: */
        memcpy(features, "standard", 9);
        cp = features;
        size = sizeof(features);
        sep = "";
        for (i = 0; i < ARRAY_SIZE(feature_bits) && size > 1; ++i) {
                if (mask & feature_bits[i].mask) {
                        cp += snprintf(cp, size, "%s%s", sep,
                                       feature_bits[i].feature_name),
                        sep = ", ";
                        mask &= ~feature_bits[i].mask;
                        size = sizeof(features) - (cp - features);
                }
        }
        if (mask && size > 1) {
                /* print unknown features as a hex value */
                snprintf(cp, size, "%s0x%lx", sep, mask);
        }

        proc_freq = cpufreq_quick_get(cpunum);
        if (!proc_freq)
                proc_freq = c->proc_freq / 1000;

        seq_printf(m,
                   "processor  : %d\n"
                   "vendor     : %s\n"
                   "arch       : IA-64\n"
                   "family     : %u\n"
                   "model      : %u\n"
                   "model name : %s\n"
                   "revision   : %u\n"
                   "archrev    : %u\n"
                   "features   : %s\n"
                   "cpu number : %lu\n"
                   "cpu regs   : %u\n"
                   "cpu MHz    : %lu.%03lu\n"
                   "itc MHz    : %lu.%06lu\n"
                   "BogoMIPS   : %lu.%02lu\n",
                   cpunum, c->vendor, c->family, c->model,
                   c->model_name, c->revision, c->archrev,
                   features, c->ppn, c->number,
                   proc_freq / 1000, proc_freq % 1000,
                   c->itc_freq / 1000000, c->itc_freq % 1000000,
                   lpj*HZ/500000, (lpj*HZ/5000) % 100);
#ifdef CONFIG_SMP
        seq_printf(m, "siblings   : %u\n",
                   cpumask_weight(&cpu_core_map[cpunum]));
        if (c->socket_id != -1)
                seq_printf(m, "physical id: %u\n", c->socket_id);
        if (c->threads_per_core > 1 || c->cores_per_socket > 1)
                seq_printf(m,
                           "core id    : %u\n"
                           "thread id  : %u\n",
                           c->core_id, c->thread_id);
#endif
        seq_printf(m,"\n");

        return 0;
}

static void *
c_start (struct seq_file *m, loff_t *pos)
{
#ifdef CONFIG_SMP
        while (*pos < nr_cpu_ids && !cpu_online(*pos))
                ++*pos;
#endif
        return *pos < nr_cpu_ids ? cpu_data(*pos) : NULL;
}

static void *
c_next (struct seq_file *m, void *v, loff_t *pos)
{
        ++*pos;
        return c_start(m, pos);
}

static void
c_stop (struct seq_file *m, void *v)
{
}

const struct seq_operations cpuinfo_op = {
        .start =        c_start,
        .next =         c_next,
        .stop =         c_stop,
        .show =         show_cpuinfo
};

#define MAX_BRANDS      8
static char brandname[MAX_BRANDS][128];

static char *
get_model_name(__u8 family, __u8 model)
{
        static int overflow;
        char brand[128];
        int i;

        memcpy(brand, "Unknown", 8);
        if (ia64_pal_get_brand_info(brand)) {
                if (family == 0x7)
                        memcpy(brand, "Merced", 7);
                else if (family == 0x1f) switch (model) {
                        case 0: memcpy(brand, "McKinley", 9); break;
                        case 1: memcpy(brand, "Madison", 8); break;
                        case 2: memcpy(brand, "Madison up to 9M cache", 23); break;
                }
        }
        for (i = 0; i < MAX_BRANDS; i++)
                if (strcmp(brandname[i], brand) == 0)
                        return brandname[i];
        for (i = 0; i < MAX_BRANDS; i++)
                if (brandname[i][0] == '\0')
                        return strcpy(brandname[i], brand);
        if (overflow++ == 0)
                printk(KERN_ERR
                       "%s: Table overflow. Some processor model information will be missing\n",
                       __func__);
        return "Unknown";
}

static void
identify_cpu (struct cpuinfo_ia64 *c)
{
        union {
                unsigned long bits[5];
                struct {
                        /* id 0 & 1: */
                        char vendor[16];

                        /* id 2 */
                        u64 ppn;                /* processor serial number */

                        /* id 3: */
                        unsigned number         :  8;
                        unsigned revision       :  8;
                        unsigned model          :  8;
                        unsigned family         :  8;
                        unsigned archrev        :  8;
                        unsigned reserved       : 24;

                        /* id 4: */
                        u64 features;
                } field;
        } cpuid;
        pal_vm_info_1_u_t vm1;
        pal_vm_info_2_u_t vm2;
        pal_status_t status;
        unsigned long impl_va_msb = 50, phys_addr_size = 44;    /* Itanium defaults */
        int i;
        for (i = 0; i < 5; ++i)
                cpuid.bits[i] = ia64_get_cpuid(i);

        memcpy(c->vendor, cpuid.field.vendor, 16);
#ifdef CONFIG_SMP
        c->cpu = smp_processor_id();

        /* below default values will be overwritten  by identify_siblings() 
         * for Multi-Threading/Multi-Core capable CPUs
         */
        c->threads_per_core = c->cores_per_socket = c->num_log = 1;
        c->socket_id = -1;

        identify_siblings(c);

        if (c->threads_per_core > smp_num_siblings)
                smp_num_siblings = c->threads_per_core;
#endif
        c->ppn = cpuid.field.ppn;
        c->number = cpuid.field.number;
        c->revision = cpuid.field.revision;
        c->model = cpuid.field.model;
        c->family = cpuid.field.family;
        c->archrev = cpuid.field.archrev;
        c->features = cpuid.field.features;
        c->model_name = get_model_name(c->family, c->model);

        status = ia64_pal_vm_summary(&vm1, &vm2);
        if (status == PAL_STATUS_SUCCESS) {
                impl_va_msb = vm2.pal_vm_info_2_s.impl_va_msb;
                phys_addr_size = vm1.pal_vm_info_1_s.phys_add_size;
        }
        c->unimpl_va_mask = ~((7L<<61) | ((1L << (impl_va_msb + 1)) - 1));
        c->unimpl_pa_mask = ~((1L<<63) | ((1L << phys_addr_size) - 1));
}

/*
 * Do the following calculations:
 *
 * 1. the max. cache line size.
 * 2. the minimum of the i-cache stride sizes for "flush_icache_range()".
 * 3. the minimum of the cache stride sizes for "clflush_cache_range()".
 */
static void
get_cache_info(void)
{
        unsigned long line_size, max = 1;
        unsigned long l, levels, unique_caches;
        pal_cache_config_info_t cci;
        long status;

        status = ia64_pal_cache_summary(&levels, &unique_caches);
        if (status != 0) {
                printk(KERN_ERR "%s: ia64_pal_cache_summary() failed (status=%ld)\n",
                       __func__, status);
                max = SMP_CACHE_BYTES;
                /* Safest setup for "flush_icache_range()" */
                ia64_i_cache_stride_shift = I_CACHE_STRIDE_SHIFT;
                /* Safest setup for "clflush_cache_range()" */
                ia64_cache_stride_shift = CACHE_STRIDE_SHIFT;
                goto out;
        }

        for (l = 0; l < levels; ++l) {
                /* cache_type (data_or_unified)=2 */
                status = ia64_pal_cache_config_info(l, 2, &cci);
                if (status != 0) {
                        printk(KERN_ERR "%s: ia64_pal_cache_config_info"
                                "(l=%lu, 2) failed (status=%ld)\n",
                                __func__, l, status);
                        max = SMP_CACHE_BYTES;
                        /* The safest setup for "flush_icache_range()" */
                        cci.pcci_stride = I_CACHE_STRIDE_SHIFT;
                        /* The safest setup for "clflush_cache_range()" */
                        ia64_cache_stride_shift = CACHE_STRIDE_SHIFT;
                        cci.pcci_unified = 1;
                } else {
                        if (cci.pcci_stride < ia64_cache_stride_shift)
                                ia64_cache_stride_shift = cci.pcci_stride;

                        line_size = 1 << cci.pcci_line_size;
                        if (line_size > max)
                                max = line_size;
                }

                if (!cci.pcci_unified) {
                        /* cache_type (instruction)=1*/
                        status = ia64_pal_cache_config_info(l, 1, &cci);
                        if (status != 0) {
                                printk(KERN_ERR "%s: ia64_pal_cache_config_info"
                                        "(l=%lu, 1) failed (status=%ld)\n",
                                        __func__, l, status);
                                /* The safest setup for flush_icache_range() */
                                cci.pcci_stride = I_CACHE_STRIDE_SHIFT;
                        }
                }
                if (cci.pcci_stride < ia64_i_cache_stride_shift)
                        ia64_i_cache_stride_shift = cci.pcci_stride;
        }
  out:
        if (max > ia64_max_cacheline_size)
                ia64_max_cacheline_size = max;
}

/*
 * cpu_init() initializes state that is per-CPU.  This function acts
 * as a 'CPU state barrier', nothing should get across.
 */
void
cpu_init (void)
{
        extern void ia64_mmu_init(void *);
        static unsigned long max_num_phys_stacked = IA64_NUM_PHYS_STACK_REG;
        unsigned long num_phys_stacked;
        pal_vm_info_2_u_t vmi;
        unsigned int max_ctx;
        struct cpuinfo_ia64 *cpu_info;
        void *cpu_data;

        cpu_data = per_cpu_init();
#ifdef CONFIG_SMP
        /*
         * insert boot cpu into sibling and core mapes
         * (must be done after per_cpu area is setup)
         */
        if (smp_processor_id() == 0) {
                cpumask_set_cpu(0, &per_cpu(cpu_sibling_map, 0));
                cpumask_set_cpu(0, &cpu_core_map[0]);
        } else {
                /*
                 * Set ar.k3 so that assembly code in MCA handler can compute
                 * physical addresses of per cpu variables with a simple:
                 *   phys = ar.k3 + &per_cpu_var
                 * and the alt-dtlb-miss handler can set per-cpu mapping into
                 * the TLB when needed. head.S already did this for cpu0.
                 */
                ia64_set_kr(IA64_KR_PER_CPU_DATA,
                            ia64_tpa(cpu_data) - (long) __per_cpu_start);
        }
#endif

        get_cache_info();

        /*
         * We can't pass "local_cpu_data" to identify_cpu() because we haven't called
         * ia64_mmu_init() yet.  And we can't call ia64_mmu_init() first because it
         * depends on the data returned by identify_cpu().  We break the dependency by
         * accessing cpu_data() through the canonical per-CPU address.
         */
        cpu_info = cpu_data + ((char *) &__ia64_per_cpu_var(ia64_cpu_info) - __per_cpu_start);
        identify_cpu(cpu_info);

#ifdef CONFIG_MCKINLEY
        {
#               define FEATURE_SET 16
                struct ia64_pal_retval iprv;

                if (cpu_info->family == 0x1f) {
                        PAL_CALL_PHYS(iprv, PAL_PROC_GET_FEATURES, 0, FEATURE_SET, 0);
                        if ((iprv.status == 0) && (iprv.v0 & 0x80) && (iprv.v2 & 0x80))
                                PAL_CALL_PHYS(iprv, PAL_PROC_SET_FEATURES,
                                              (iprv.v1 | 0x80), FEATURE_SET, 0);
                }
        }
#endif

        /* Clear the stack memory reserved for pt_regs: */
        memset(task_pt_regs(current), 0, sizeof(struct pt_regs));

        ia64_set_kr(IA64_KR_FPU_OWNER, 0);

        /*
         * Initialize the page-table base register to a global
         * directory with all zeroes.  This ensure that we can handle
         * TLB-misses to user address-space even before we created the
         * first user address-space.  This may happen, e.g., due to
         * aggressive use of lfetch.fault.
         */
        ia64_set_kr(IA64_KR_PT_BASE, __pa(ia64_imva(empty_zero_page)));

        /*
         * Initialize default control register to defer speculative faults except
         * for those arising from TLB misses, which are not deferred.  The
         * kernel MUST NOT depend on a particular setting of these bits (in other words,
         * the kernel must have recovery code for all speculative accesses).  Turn on
         * dcr.lc as per recommendation by the architecture team.  Most IA-32 apps
         * shouldn't be affected by this (moral: keep your ia32 locks aligned and you'll
         * be fine).
         */
        ia64_setreg(_IA64_REG_CR_DCR,  (  IA64_DCR_DP | IA64_DCR_DK | IA64_DCR_DX | IA64_DCR_DR
                                        | IA64_DCR_DA | IA64_DCR_DD | IA64_DCR_LC));
        mmgrab(&init_mm);
        current->active_mm = &init_mm;
        BUG_ON(current->mm);

        ia64_mmu_init(ia64_imva(cpu_data));
        ia64_mca_cpu_init(ia64_imva(cpu_data));

        /* Clear ITC to eliminate sched_clock() overflows in human time.  */
        ia64_set_itc(0);

        /* disable all local interrupt sources: */
        ia64_set_itv(1 << 16);
        ia64_set_lrr0(1 << 16);
        ia64_set_lrr1(1 << 16);
        ia64_setreg(_IA64_REG_CR_PMV, 1 << 16);
        ia64_setreg(_IA64_REG_CR_CMCV, 1 << 16);

        /* clear TPR & XTP to enable all interrupt classes: */
        ia64_setreg(_IA64_REG_CR_TPR, 0);

        /* Clear any pending interrupts left by SAL/EFI */
        while (ia64_get_ivr() != IA64_SPURIOUS_INT_VECTOR)
                ia64_eoi();

#ifdef CONFIG_SMP
        normal_xtp();
#endif

        /* set ia64_ctx.max_rid to the maximum RID that is supported by all CPUs: */
        if (ia64_pal_vm_summary(NULL, &vmi) == 0) {
                max_ctx = (1U << (vmi.pal_vm_info_2_s.rid_size - 3)) - 1;
                setup_ptcg_sem(vmi.pal_vm_info_2_s.max_purges, NPTCG_FROM_PAL);
        } else {
                printk(KERN_WARNING "cpu_init: PAL VM summary failed, assuming 18 RID bits\n");
                max_ctx = (1U << 15) - 1;       /* use architected minimum */
        }
        while (max_ctx < ia64_ctx.max_ctx) {
                unsigned int old = ia64_ctx.max_ctx;
                if (cmpxchg(&ia64_ctx.max_ctx, old, max_ctx) == old)
                        break;
        }

        if (ia64_pal_rse_info(&num_phys_stacked, NULL) != 0) {
                printk(KERN_WARNING "cpu_init: PAL RSE info failed; assuming 96 physical "
                       "stacked regs\n");
                num_phys_stacked = 96;
        }
        /* size of physical stacked register partition plus 8 bytes: */
        if (num_phys_stacked > max_num_phys_stacked) {
                ia64_patch_phys_stack_reg(num_phys_stacked*8 + 8);
                max_num_phys_stacked = num_phys_stacked;
        }
        platform_cpu_init();
}

void __init
check_bugs (void)
{
        ia64_patch_mckinley_e9((unsigned long) __start___mckinley_e9_bundles,
                               (unsigned long) __end___mckinley_e9_bundles);
}

static int __init run_dmi_scan(void)
{
        dmi_scan_machine();
        dmi_memdev_walk();
        dmi_set_dump_stack_arch_desc();
        return 0;
}
core_initcall(run_dmi_scan);