Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * handle transition of Linux booting another kernel

 * Copyright (C) 2002-2005 Eric Biederman  <ebiederm@xmission.com>

 *

 * This source code is licensed under the GNU General Public License,

 * Version 2.  See the file COPYING for more details.

 */

#include <linux/mm.h>

#include <linux/kexec.h>

#include <linux/delay.h>

#include <linux/init.h>

#include <linux/numa.h>

#include <asm/pgtable.h>

#include <asm/pgalloc.h>

#include <asm/tlbflush.h>

#include <asm/mmu_context.h>

#include <asm/io.h>

#include <asm/apic.h>

#include <asm/cpufeature.h>

#include <asm/desc.h>

#include <asm/system.h>

#define PAGE_ALIGNED __attribute__ ((__aligned__(PAGE_SIZE)))

static u32 kexec_pgd[1024] PAGE_ALIGNED;

#ifdef CONFIG_X86_PAE

static u32 kexec_pmd0[1024] PAGE_ALIGNED;

static u32 kexec_pmd1[1024] PAGE_ALIGNED;

#endif

static u32 kexec_pte0[1024] PAGE_ALIGNED;

static u32 kexec_pte1[1024] PAGE_ALIGNED;

static void set_idt(void *newidt, __u16 limit)

{

        struct Xgt_desc_struct curidt;

        /* ia32 supports unaliged loads & stores */

        curidt.size    = limit;

        curidt.address = (unsigned long)newidt;

        load_idt(&curidt);

};

static void set_gdt(void *newgdt, __u16 limit)

{

        struct Xgt_desc_struct curgdt;

        /* ia32 supports unaligned loads & stores */

        curgdt.size    = limit;

        curgdt.address = (unsigned long)newgdt;

        load_gdt(&curgdt);

};

static void load_segments(void)

{

#define __STR(X) #X

#define STR(X) __STR(X)

        __asm__ __volatile__ (

                "\tljmp $"STR(__KERNEL_CS)",$1f\n"

                "\t1:\n"

                "\tmovl $"STR(__KERNEL_DS)",%%eax\n"

                "\tmovl %%eax,%%ds\n"

                "\tmovl %%eax,%%es\n"

                "\tmovl %%eax,%%fs\n"

                "\tmovl %%eax,%%gs\n"

                "\tmovl %%eax,%%ss\n"

                ::: "eax", "memory");

#undef STR

#undef __STR

}

/*

 * A architecture hook called to validate the

 * proposed image and prepare the control pages

 * as needed.  The pages for KEXEC_CONTROL_CODE_SIZE

 * have been allocated, but the segments have yet

 * been copied into the kernel.

 *

 * Do what every setup is needed on image and the

 * reboot code buffer to allow us to avoid allocations

 * later.

 *

 * Currently nothing.

 */

int machine_kexec_prepare(struct kimage *image)

{

        return 0;

}

/*

 * Undo anything leftover by machine_kexec_prepare

 * when an image is freed.

 */

void machine_kexec_cleanup(struct kimage *image)

{

}

/*

 * Do not allocate memory (or fail in any way) in machine_kexec().

 * We are past the point of no return, committed to rebooting now.

 */

NORET_TYPE void machine_kexec(struct kimage *image)

{

        unsigned long page_list[PAGES_NR];

        void *control_page;

        /* Interrupts aren't acceptable while we reboot */

        local_irq_disable();

        control_page = page_address(image->control_code_page);

        memcpy(control_page, relocate_kernel, PAGE_SIZE);

        page_list[PA_CONTROL_PAGE] = __pa(control_page);

        page_list[VA_CONTROL_PAGE] = (unsigned long)relocate_kernel;

        page_list[PA_PGD] = __pa(kexec_pgd);

        page_list[VA_PGD] = (unsigned long)kexec_pgd;

#ifdef CONFIG_X86_PAE

        page_list[PA_PMD_0] = __pa(kexec_pmd0);

        page_list[VA_PMD_0] = (unsigned long)kexec_pmd0;

        page_list[PA_PMD_1] = __pa(kexec_pmd1);

        page_list[VA_PMD_1] = (unsigned long)kexec_pmd1;

#endif

        page_list[PA_PTE_0] = __pa(kexec_pte0);

        page_list[VA_PTE_0] = (unsigned long)kexec_pte0;

        page_list[PA_PTE_1] = __pa(kexec_pte1);

        page_list[VA_PTE_1] = (unsigned long)kexec_pte1;

        /* The segment registers are funny things, they have both a

         * visible and an invisible part.  Whenever the visible part is

         * set to a specific selector, the invisible part is loaded

         * with from a table in memory.  At no other time is the

         * descriptor table in memory accessed.

         *

         * I take advantage of this here by force loading the

         * segments, before I zap the gdt with an invalid value.

         */

        load_segments();

        /* The gdt & idt are now invalid.

         * If you want to load them you must set up your own idt & gdt.

         */

        set_gdt(phys_to_virt(0),0);

        set_idt(phys_to_virt(0),0);

        /* now call it */

        relocate_kernel((unsigned long)image->head, (unsigned long)page_list,

                        image->start, cpu_has_pae);

}

void arch_crash_save_vmcoreinfo(void)

{

#ifdef CONFIG_ARCH_DISCONTIGMEM_ENABLE

        VMCOREINFO_SYMBOL(node_data);

        VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);

#endif

#ifdef CONFIG_X86_PAE

        VMCOREINFO_CONFIG(X86_PAE);

#endif

}