r4k_switch.S (1546B)
1/* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file "COPYING" in the main directory of this archive 4 * for more details. 5 * 6 * Copyright (C) 1994, 1995, 1996, 1998, 1999, 2002, 2003 Ralf Baechle 7 * Copyright (C) 1996 David S. Miller (davem@davemloft.net) 8 * Copyright (C) 1994, 1995, 1996, by Andreas Busse 9 * Copyright (C) 1999 Silicon Graphics, Inc. 10 * Copyright (C) 2000 MIPS Technologies, Inc. 11 * written by Carsten Langgaard, carstenl@mips.com 12 */ 13#include <asm/asm.h> 14#include <asm/cachectl.h> 15#include <asm/mipsregs.h> 16#include <asm/asm-offsets.h> 17#include <asm/regdef.h> 18#include <asm/stackframe.h> 19#include <asm/thread_info.h> 20 21#include <asm/asmmacro.h> 22 23/* 24 * task_struct *resume(task_struct *prev, task_struct *next, 25 * struct thread_info *next_ti) 26 */ 27 .align 5 28 LEAF(resume) 29 mfc0 t1, CP0_STATUS 30 LONG_S t1, THREAD_STATUS(a0) 31 cpu_save_nonscratch a0 32 LONG_S ra, THREAD_REG31(a0) 33 34#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) 35 PTR_LA t8, __stack_chk_guard 36 LONG_L t9, TASK_STACK_CANARY(a1) 37 LONG_S t9, 0(t8) 38#endif 39 40 /* 41 * The order of restoring the registers takes care of the race 42 * updating $28, $29 and kernelsp without disabling ints. 43 */ 44 move $28, a2 45 cpu_restore_nonscratch a1 46 47 PTR_ADDU t0, $28, _THREAD_SIZE - 32 48 set_saved_sp t0, t1, t2 49 mfc0 t1, CP0_STATUS /* Do we really need this? */ 50 li a3, 0xff01 51 and t1, a3 52 LONG_L a2, THREAD_STATUS(a1) 53 nor a3, $0, a3 54 and a2, a3 55 or a2, t1 56 mtc0 a2, CP0_STATUS 57 move v0, a0 58 jr ra 59 END(resume)