| /* 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_CC_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) |
