1/* 2 * Copyright 2004-2009 Analog Devices Inc. 3 * 4 * Licensed under the GPL-2 or later 5 */ 6 7#include <linux/linkage.h> 8#include <asm/thread_info.h> 9#include <asm/errno.h> 10#include <asm/blackfin.h> 11#include <asm/asm-offsets.h> 12 13#include <asm/context.S> 14 15#ifdef CONFIG_EXCPT_IRQ_SYSC_L1 16.section .l1.text 17#else 18.text 19#endif 20 21ENTRY(_ret_from_fork) 22#ifdef CONFIG_IPIPE 23 /* 24 * Hw IRQs are off on entry, and we don't want the scheduling tail 25 * code to starve high priority domains from interrupts while it 26 * runs. Therefore we first stall the root stage to have the 27 * virtual interrupt state reflect IMASK. 28 */ 29 p0.l = ___ipipe_root_status; 30 p0.h = ___ipipe_root_status; 31 r4 = [p0]; 32 bitset(r4, 0); 33 [p0] = r4; 34 /* 35 * Then we may enable hw IRQs, allowing preemption from high 36 * priority domains. schedule_tail() will do local_irq_enable() 37 * since Blackfin does not define __ARCH_WANT_UNLOCKED_CTXSW, so 38 * there is no need to unstall the root domain by ourselves 39 * afterwards. 40 */ 41 p0.l = _bfin_irq_flags; 42 p0.h = _bfin_irq_flags; 43 r4 = [p0]; 44 sti r4; 45#endif /* CONFIG_IPIPE */ 46 SP += -12; 47 pseudo_long_call _schedule_tail, p5; 48 SP += 12; 49 r0 = [sp + PT_IPEND]; 50 cc = bittst(r0,1); 51 if cc jump .Lin_kernel; 52 RESTORE_CONTEXT 53 rti; 54.Lin_kernel: 55 bitclr(r0,1); 56 [sp + PT_IPEND] = r0; 57 /* do a 'fake' RTI by jumping to [RETI] 58 * to avoid clearing supervisor mode in child 59 */ 60 r0 = [sp + PT_PC]; 61 [sp + PT_P0] = r0; 62 63 RESTORE_ALL_SYS 64 jump (p0); 65ENDPROC(_ret_from_fork) 66 67ENTRY(_sys_fork) 68 r0 = -EINVAL; 69#if ANOMALY_05000371 70 nop; 71 nop; 72 nop; 73#endif 74 rts; 75ENDPROC(_sys_fork) 76 77ENTRY(_sys_vfork) 78 r0 = sp; 79 r0 += 24; 80 [--sp] = rets; 81 SP += -12; 82 pseudo_long_call _bfin_vfork, p2; 83 SP += 12; 84 rets = [sp++]; 85 rts; 86ENDPROC(_sys_vfork) 87 88ENTRY(_sys_clone) 89 r0 = sp; 90 r0 += 24; 91 [--sp] = rets; 92 SP += -12; 93 pseudo_long_call _bfin_clone, p2; 94 SP += 12; 95 rets = [sp++]; 96 rts; 97ENDPROC(_sys_clone) 98 99ENTRY(_sys_rt_sigreturn) 100 r0 = sp; 101 r0 += 24; 102 [--sp] = rets; 103 SP += -12; 104 pseudo_long_call _do_rt_sigreturn, p2; 105 SP += 12; 106 rets = [sp++]; 107 rts; 108ENDPROC(_sys_rt_sigreturn) 109