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Bryan Wu1394f032007-05-06 14:50:22 -07001/*
Robin Getz96f10502009-09-24 14:11:24 +00002 * Copyright 2004-2009 Analog Devices Inc.
Bryan Wu1394f032007-05-06 14:50:22 -07003 *
Robin Getz96f10502009-09-24 14:11:24 +00004 * Licensed under the GPL-2 or later
Bryan Wu1394f032007-05-06 14:50:22 -07005 */
6
7#include <linux/linkage.h>
8#include <asm/thread_info.h>
9#include <asm/errno.h>
Graf Yang8f658732008-11-18 17:48:22 +080010#include <asm/blackfin.h>
Bryan Wu1394f032007-05-06 14:50:22 -070011#include <asm/asm-offsets.h>
12
Bryan Wu639f6572008-08-27 10:51:02 +080013#include <asm/context.S>
Bryan Wu1394f032007-05-06 14:50:22 -070014
15#ifdef CONFIG_EXCPT_IRQ_SYSC_L1
16.section .l1.text
17#else
18.text
19#endif
20
21ENTRY(_ret_from_fork)
Yi Li6a01f232009-01-07 23:14:39 +080022#ifdef CONFIG_IPIPE
Philippe Gerum6b8019c82009-06-22 18:23:32 +020023 /*
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;
Yi Li6a01f232009-01-07 23:14:39 +080045#endif /* CONFIG_IPIPE */
Bryan Wu1394f032007-05-06 14:50:22 -070046 SP += -12;
Barry Songd86bfb12010-01-07 04:11:17 +000047 pseudo_long_call _schedule_tail, p5;
Bryan Wu1394f032007-05-06 14:50:22 -070048 SP += 12;
Al Viroee1e17c2012-10-13 03:22:53 -040049 p1 = [sp++];
50 r0 = [sp++];
51 cc = p1 == 0;
52 if cc jump .Lfork;
53 sp += -12;
54 call (p1);
55 sp += 12;
56.Lfork:
Bryan Wu1394f032007-05-06 14:50:22 -070057 RESTORE_CONTEXT
58 rti;
Mike Frysinger51be24c2007-06-11 15:31:30 +080059ENDPROC(_ret_from_fork)