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/blackfin.h>
  34 #include <asm/asm-offsets.h>
  35
  36 #include <asm/context.S>
  37
  38 #ifdef CONFIG_EXCPT_IRQ_SYSC_L1
  39 .section .l1.text
  40 #else
  41 .text
  42 #endif
  43
  44 ENTRY(_ret_from_fork)
  45 #ifdef CONFIG_IPIPE
  46         [--sp] = reti;          /* IRQs on. */
  47         SP += 4;
  48 #endif /* CONFIG_IPIPE */
  49         SP += -12;
  50         call _schedule_tail;
  51         SP += 12;
  52         r0 = [sp + PT_IPEND];
  53         cc = bittst(r0,1);
  54         if cc jump .Lin_kernel;
  55         RESTORE_CONTEXT
  56         rti;
  57 .Lin_kernel:
  58         bitclr(r0,1);
  59         [sp + PT_IPEND] = r0;
  60         /* do a 'fake' RTI by jumping to [RETI]
  61          * to avoid clearing supervisor mode in child
  62          */
  63         r0 = [sp + PT_PC];
  64         [sp + PT_P0] = r0;
  65
  66         RESTORE_ALL_SYS
  67         jump (p0);
  68 ENDPROC(_ret_from_fork)
  69
  70 ENTRY(_sys_fork)
  71         r0 = -EINVAL;
  72 #if (ANOMALY_05000371)
  73         nop;
  74         nop;
  75         nop;
  76 #endif
  77         rts;
  78 ENDPROC(_sys_fork)
  79
  80 ENTRY(_sys_vfork)
  81         r0 = sp;
  82         r0 += 24;
  83         [--sp] = rets;
  84         SP += -12;
  85         call _bfin_vfork;
  86         SP += 12;
  87         rets = [sp++];
  88         rts;
  89 ENDPROC(_sys_vfork)
  90
  91 ENTRY(_sys_clone)
  92         r0 = sp;
  93         r0 += 24;
  94         [--sp] = rets;
  95         SP += -12;
  96         call _bfin_clone;
  97         SP += 12;
  98         rets = [sp++];
  99         rts;
 100 ENDPROC(_sys_clone)
 101
 102 ENTRY(_sys_rt_sigreturn)
 103         r0 = sp;
 104         r0 += 24;
 105         [--sp] = rets;
 106         SP += -12;
 107         call _do_rt_sigreturn;
 108         SP += 12;
 109         rets = [sp++];
 110         rts;
 111 ENDPROC(_sys_rt_sigreturn)