arch/blackfin/kernel/entry.S

   1 /*
   2  * File:         arch/blackfin/kernel/entry.S
   3  * Based on:
   4  * Author:
   5  *
   6  * Created:
   7  * Description:
   8  *
   9  * Modified:
  10  *               Copyright 2004-2006 Analog Devices Inc.
  11  *
  12  * Bugs:         Enter bugs at http://blackfin.uclinux.org/
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * This program is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with this program; if not, see the file COPYING, or write
  26  * to the Free Software Foundation, Inc.,
  27  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  28  */
  29
  30 #include <linux/linkage.h>
  31 #include <asm/thread_info.h>
  32 #include <asm/errno.h>
  33 #include <asm/asm-offsets.h>
  34
  35 #include <asm/context.S>
  36
  37 #ifdef CONFIG_EXCPT_IRQ_SYSC_L1
  38 .section .l1.text
  39 #else
  40 .text
  41 #endif
  42
  43 ENTRY(_ret_from_fork)
  44         SP += -12;
  45         call _schedule_tail;
  46         SP += 12;
  47         r0 = [sp + PT_IPEND];
  48         cc = bittst(r0,1);
  49         if cc jump .Lin_kernel;
  50         RESTORE_CONTEXT
  51         rti;
  52 .Lin_kernel:
  53         bitclr(r0,1);
  54         [sp + PT_IPEND] = r0;
  55         /* do a 'fake' RTI by jumping to [RETI]
  56          * to avoid clearing supervisor mode in child
  57          */
  58         r0 = [sp + PT_PC];
  59         [sp + PT_P0] = r0;
  60
  61         RESTORE_ALL_SYS
  62         jump (p0);
  63 ENDPROC(_ret_from_fork)
  64
  65 ENTRY(_sys_fork)
  66         r0 = -EINVAL;
  67 #if (ANOMALY_05000371)
  68         nop;
  69         nop;
  70         nop;
  71 #endif
  72         rts;
  73 ENDPROC(_sys_fork)
  74
  75 ENTRY(_sys_vfork)
  76         r0 = sp;
  77         r0 += 24;
  78         [--sp] = rets;
  79         SP += -12;
  80         call _bfin_vfork;
  81         SP += 12;
  82         rets = [sp++];
  83         rts;
  84 ENDPROC(_sys_vfork)
  85
  86 ENTRY(_sys_clone)
  87         r0 = sp;
  88         r0 += 24;
  89         [--sp] = rets;
  90         SP += -12;
  91         call _bfin_clone;
  92         SP += 12;
  93         rets = [sp++];
  94         rts;
  95 ENDPROC(_sys_clone)
  96
  97 ENTRY(_sys_rt_sigreturn)
  98         r0 = sp;
  99         r0 += 24;
 100         [--sp] = rets;
 101         SP += -12;
 102         call _do_rt_sigreturn;
 103         SP += 12;
 104         rets = [sp++];
 105         rts;
 106 ENDPROC(_sys_rt_sigreturn)