diff options
Diffstat (limited to 'arch/blackfin/kernel/entry.S')
| -rw-r--r-- | arch/blackfin/kernel/entry.S | 51 |
1 files changed, 24 insertions, 27 deletions
diff --git a/arch/blackfin/kernel/entry.S b/arch/blackfin/kernel/entry.S index a9cfba9946b5..f27dc2292e1b 100644 --- a/arch/blackfin/kernel/entry.S +++ b/arch/blackfin/kernel/entry.S @@ -1,30 +1,7 @@ /* - * File: arch/blackfin/kernel/entry.S - * Based on: - * Author: + * Copyright 2004-2009 Analog Devices Inc. * - * Created: - * Description: - * - * Modified: - * Copyright 2004-2006 Analog Devices Inc. - * - * Bugs: Enter bugs at http://blackfin.uclinux.org/ - * - * 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. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, see the file COPYING, or write - * to the Free Software Foundation, Inc., - * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * Licensed under the GPL-2 or later */ #include <linux/linkage.h> @@ -43,8 +20,28 @@ ENTRY(_ret_from_fork) #ifdef CONFIG_IPIPE - [--sp] = reti; /* IRQs on. */ - SP += 4; + /* + * Hw IRQs are off on entry, and we don't want the scheduling tail + * code to starve high priority domains from interrupts while it + * runs. Therefore we first stall the root stage to have the + * virtual interrupt state reflect IMASK. + */ + p0.l = ___ipipe_root_status; + p0.h = ___ipipe_root_status; + r4 = [p0]; + bitset(r4, 0); + [p0] = r4; + /* + * Then we may enable hw IRQs, allowing preemption from high + * priority domains. schedule_tail() will do local_irq_enable() + * since Blackfin does not define __ARCH_WANT_UNLOCKED_CTXSW, so + * there is no need to unstall the root domain by ourselves + * afterwards. + */ + p0.l = _bfin_irq_flags; + p0.h = _bfin_irq_flags; + r4 = [p0]; + sti r4; #endif /* CONFIG_IPIPE */ SP += -12; call _schedule_tail; |