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Diffstat (limited to 'arch/mips/kernel/r2300_switch.S')
| -rw-r--r-- | arch/mips/kernel/r2300_switch.S | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/arch/mips/kernel/r2300_switch.S b/arch/mips/kernel/r2300_switch.S new file mode 100644 index 000000000..71b1aafae --- /dev/null +++ b/arch/mips/kernel/r2300_switch.S @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * r2300_switch.S: R2300 specific task switching code. + * + * Copyright (C) 1994, 1995, 1996, 1999 by Ralf Baechle + * Copyright (C) 1994, 1995, 1996 by Andreas Busse + * + * Multi-cpu abstraction and macros for easier reading: + * Copyright (C) 1996 David S. Miller (davem@davemloft.net) + * + * Further modifications to make this work: + * Copyright (c) 1998-2000 Harald Koerfgen + */ +#include <asm/asm.h> +#include <asm/cachectl.h> +#include <asm/export.h> +#include <asm/fpregdef.h> +#include <asm/mipsregs.h> +#include <asm/asm-offsets.h> +#include <asm/regdef.h> +#include <asm/stackframe.h> +#include <asm/thread_info.h> + +#include <asm/asmmacro.h> + + .set mips1 + .align 5 + +/* + * task_struct *resume(task_struct *prev, task_struct *next, + * struct thread_info *next_ti) + */ +LEAF(resume) + mfc0 t1, CP0_STATUS + sw t1, THREAD_STATUS(a0) + cpu_save_nonscratch a0 + sw ra, THREAD_REG31(a0) + +#if defined(CONFIG_STACKPROTECTOR) && !defined(CONFIG_SMP) + PTR_LA t8, __stack_chk_guard + LONG_L t9, TASK_STACK_CANARY(a1) + LONG_S t9, 0(t8) +#endif + + /* + * The order of restoring the registers takes care of the race + * updating $28, $29 and kernelsp without disabling ints. + */ + move $28, a2 + cpu_restore_nonscratch a1 + + addiu t1, $28, _THREAD_SIZE - 32 + sw t1, kernelsp + + mfc0 t1, CP0_STATUS /* Do we really need this? */ + li a3, 0xff01 + and t1, a3 + lw a2, THREAD_STATUS(a1) + nor a3, $0, a3 + and a2, a3 + or a2, t1 + mtc0 a2, CP0_STATUS + move v0, a0 + jr ra + END(resume) |