Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * Access to the shared data page by the vDSO & syscall map

 *

 * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version

 * 2 of the License, or (at your option) any later version.

 */

#include 

#include 

#include 

#include 

#include 

        .text

V_FUNCTION_BEGIN(__get_datapage)

  .cfi_startproc

        /* We don't want that exposed or overridable as we want other objects

         * to be able to bl directly to here

         */

        .protected __get_datapage

        .hidden __get_datapage

        mflr    r0

  .cfi_register lr,r0

        bcl     20,31,1f

        .global __kernel_datapage_offset;

__kernel_datapage_offset:

        .long   0

1:

        mflr    r3

        mtlr    r0

        lwz     r0,0(r3)

        add     r3,r0,r3

        blr

  .cfi_endproc

V_FUNCTION_END(__get_datapage)

/*

 * void *__kernel_get_syscall_map(unsigned int *syscall_count) ;

 *

 * returns a pointer to the syscall map. the map is agnostic to the

 * size of "long", unlike kernel bitops, it stores bits from top to

 * bottom so that memory actually contains a linear bitmap

 * check for syscall N by testing bit (0x80000000 >> (N & 0x1f)) of

 * 32 bits int at N >> 5.

 */

V_FUNCTION_BEGIN(__kernel_get_syscall_map)

  .cfi_startproc

        mflr    r12

  .cfi_register lr,r12

        mr      r4,r3

        bl      V_LOCAL_FUNC(__get_datapage)

        mtlr    r12

        addi    r3,r3,CFG_SYSCALL_MAP64

        cmpli   cr0,r4,0

        crclr   cr0*4+so

        beqlr

        li      r0,__NR_syscalls

        stw     r0,0(r4)

        blr

  .cfi_endproc

V_FUNCTION_END(__kernel_get_syscall_map)

/*

 * void unsigned long  __kernel_get_tbfreq(void);

 *

 * returns the timebase frequency in HZ

 */

V_FUNCTION_BEGIN(__kernel_get_tbfreq)

  .cfi_startproc

        mflr    r12

  .cfi_register lr,r12

        bl      V_LOCAL_FUNC(__get_datapage)

        ld      r3,CFG_TB_TICKS_PER_SEC(r3)

        mtlr    r12

        crclr   cr0*4+so

        blr

  .cfi_endproc

V_FUNCTION_END(__kernel_get_tbfreq)