11da177e4SLinus Torvalds/* 21da177e4SLinus Torvalds * This file is subject to the terms and conditions of the GNU General Public 31da177e4SLinus Torvalds * License. See the file "COPYING" in the main directory of this archive 41da177e4SLinus Torvalds * for more details. 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle 71da177e4SLinus Torvalds * Copyright (C) 1999, 2000 Silicon Graphics, Inc. 81da177e4SLinus Torvalds * Copyright (C) 2001 MIPS Technologies, Inc. 91da177e4SLinus Torvalds */ 101da177e4SLinus Torvalds 111da177e4SLinus Torvalds#include <asm/asm.h> 121da177e4SLinus Torvalds#include <asm/asmmacro.h> 131da177e4SLinus Torvalds#include <asm/regdef.h> 141da177e4SLinus Torvalds#include <asm/mipsregs.h> 151da177e4SLinus Torvalds#include <asm/stackframe.h> 161da177e4SLinus Torvalds#include <asm/isadep.h> 171da177e4SLinus Torvalds#include <asm/thread_info.h> 181da177e4SLinus Torvalds#include <asm/war.h> 191da177e4SLinus Torvalds 20f431baa5SAtsushi Nemoto#ifndef CONFIG_PREEMPT 211da177e4SLinus Torvalds#define resume_kernel restore_all 227da8a581SFranck Bui-Huu#else 237da8a581SFranck Bui-Huu#define __ret_from_irq ret_from_exception 241da177e4SLinus Torvalds#endif 251da177e4SLinus Torvalds 261da177e4SLinus Torvalds .text 271da177e4SLinus Torvalds .align 5 287da8a581SFranck Bui-Huu#ifndef CONFIG_PREEMPT 297da8a581SFranck Bui-HuuFEXPORT(ret_from_exception) 307da8a581SFranck Bui-Huu local_irq_disable # preempt stop 317da8a581SFranck Bui-Huu b __ret_from_irq 327da8a581SFranck Bui-Huu#endif 33f431baa5SAtsushi NemotoFEXPORT(ret_from_irq) 34f431baa5SAtsushi Nemoto LONG_S s0, TI_REGS($28) 357da8a581SFranck Bui-HuuFEXPORT(__ret_from_irq) 36c90e6fbbSDmitry Adamushko/* 37c90e6fbbSDmitry Adamushko * We can be coming here from a syscall done in the kernel space, 38c90e6fbbSDmitry Adamushko * e.g. a failed kernel_execve(). 39c90e6fbbSDmitry Adamushko */ 40c90e6fbbSDmitry Adamushkoresume_userspace_check: 411da177e4SLinus Torvalds LONG_L t0, PT_STATUS(sp) # returning to kernel mode? 421da177e4SLinus Torvalds andi t0, t0, KU_USER 431da177e4SLinus Torvalds beqz t0, resume_kernel 441da177e4SLinus Torvalds 45c2648527SThiemo Seuferresume_userspace: 46c2648527SThiemo Seufer local_irq_disable # make sure we dont miss an 471da177e4SLinus Torvalds # interrupt setting need_resched 481da177e4SLinus Torvalds # between sampling and return 49*7c151d3dSMarkos Chandras#ifdef CONFIG_MIPSR2_TO_R6_EMULATOR 50*7c151d3dSMarkos Chandras lw k0, TI_R2_EMUL_RET($28) 51*7c151d3dSMarkos Chandras bnez k0, restore_all_from_r2_emul 52*7c151d3dSMarkos Chandras#endif 53*7c151d3dSMarkos Chandras 541da177e4SLinus Torvalds LONG_L a2, TI_FLAGS($28) # current->work 55c2648527SThiemo Seufer andi t0, a2, _TIF_WORK_MASK # (ignoring syscall_trace) 56c2648527SThiemo Seufer bnez t0, work_pending 571da177e4SLinus Torvalds j restore_all 581da177e4SLinus Torvalds 591da177e4SLinus Torvalds#ifdef CONFIG_PREEMPT 60c2648527SThiemo Seuferresume_kernel: 61a18815abSRalf Baechle local_irq_disable 621da177e4SLinus Torvalds lw t0, TI_PRE_COUNT($28) 631da177e4SLinus Torvalds bnez t0, restore_all 641da177e4SLinus Torvaldsneed_resched: 651da177e4SLinus Torvalds LONG_L t0, TI_FLAGS($28) 661da177e4SLinus Torvalds andi t1, t0, _TIF_NEED_RESCHED 671da177e4SLinus Torvalds beqz t1, restore_all 681da177e4SLinus Torvalds LONG_L t0, PT_STATUS(sp) # Interrupts off? 691da177e4SLinus Torvalds andi t0, 1 701da177e4SLinus Torvalds beqz t0, restore_all 71a18815abSRalf Baechle jal preempt_schedule_irq 72cdaed73aSRalf Baechle b need_resched 731da177e4SLinus Torvalds#endif 741da177e4SLinus Torvalds 758f54bcacSAl ViroFEXPORT(ret_from_kernel_thread) 768f54bcacSAl Viro jal schedule_tail # a0 = struct task_struct *prev 778f54bcacSAl Viro move a0, s1 788f54bcacSAl Viro jal s0 799b0e5d42SAl Viro j syscall_exit 808f54bcacSAl Viro 811da177e4SLinus TorvaldsFEXPORT(ret_from_fork) 8236c8b586SIngo Molnar jal schedule_tail # a0 = struct task_struct *prev 831da177e4SLinus Torvalds 841da177e4SLinus TorvaldsFEXPORT(syscall_exit) 851da177e4SLinus Torvalds local_irq_disable # make sure need_resched and 861da177e4SLinus Torvalds # signals dont change between 871da177e4SLinus Torvalds # sampling and return 881da177e4SLinus Torvalds LONG_L a2, TI_FLAGS($28) # current->work 891da177e4SLinus Torvalds li t0, _TIF_ALLWORK_MASK 901da177e4SLinus Torvalds and t0, a2, t0 911da177e4SLinus Torvalds bnez t0, syscall_exit_work 921da177e4SLinus Torvalds 9302f884edSAl Virorestore_all: # restore full frame 941da177e4SLinus Torvalds .set noat 951da177e4SLinus Torvalds RESTORE_TEMP 961da177e4SLinus Torvalds RESTORE_AT 971da177e4SLinus Torvalds RESTORE_STATIC 9802f884edSAl Virorestore_partial: # restore partial frame 99192ef366SRalf Baechle#ifdef CONFIG_TRACE_IRQFLAGS 100192ef366SRalf Baechle SAVE_STATIC 101192ef366SRalf Baechle SAVE_AT 102192ef366SRalf Baechle SAVE_TEMP 103192ef366SRalf Baechle LONG_L v0, PT_STATUS(sp) 104cbde5ebcSChris Dearman#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) 105cbde5ebcSChris Dearman and v0, ST0_IEP 106cbde5ebcSChris Dearman#else 107cbde5ebcSChris Dearman and v0, ST0_IE 108cbde5ebcSChris Dearman#endif 109192ef366SRalf Baechle beqz v0, 1f 110192ef366SRalf Baechle jal trace_hardirqs_on 111192ef366SRalf Baechle b 2f 112192ef366SRalf Baechle1: jal trace_hardirqs_off 113192ef366SRalf Baechle2: 114192ef366SRalf Baechle RESTORE_TEMP 115192ef366SRalf Baechle RESTORE_AT 116192ef366SRalf Baechle RESTORE_STATIC 117192ef366SRalf Baechle#endif 1181da177e4SLinus Torvalds RESTORE_SOME 1191da177e4SLinus Torvalds RESTORE_SP_AND_RET 1201da177e4SLinus Torvalds .set at 1211da177e4SLinus Torvalds 122*7c151d3dSMarkos Chandras#ifdef CONFIG_MIPSR2_TO_R6_EMULATOR 123*7c151d3dSMarkos Chandrasrestore_all_from_r2_emul: # restore full frame 124*7c151d3dSMarkos Chandras .set noat 125*7c151d3dSMarkos Chandras sw zero, TI_R2_EMUL_RET($28) # reset it 126*7c151d3dSMarkos Chandras RESTORE_TEMP 127*7c151d3dSMarkos Chandras RESTORE_AT 128*7c151d3dSMarkos Chandras RESTORE_STATIC 129*7c151d3dSMarkos Chandras RESTORE_SOME 130*7c151d3dSMarkos Chandras LONG_L sp, PT_R29(sp) 131*7c151d3dSMarkos Chandras eretnc 132*7c151d3dSMarkos Chandras .set at 133*7c151d3dSMarkos Chandras#endif 134*7c151d3dSMarkos Chandras 135c2648527SThiemo Seuferwork_pending: 136c2648527SThiemo Seufer andi t0, a2, _TIF_NEED_RESCHED # a2 is preloaded with TI_FLAGS 1371da177e4SLinus Torvalds beqz t0, work_notifysig 1381da177e4SLinus Torvaldswork_resched: 1391da177e4SLinus Torvalds jal schedule 1401da177e4SLinus Torvalds 141c2648527SThiemo Seufer local_irq_disable # make sure need_resched and 1421da177e4SLinus Torvalds # signals dont change between 1431da177e4SLinus Torvalds # sampling and return 1441da177e4SLinus Torvalds LONG_L a2, TI_FLAGS($28) 1451da177e4SLinus Torvalds andi t0, a2, _TIF_WORK_MASK # is there any work to be done 1461da177e4SLinus Torvalds # other than syscall tracing? 1471da177e4SLinus Torvalds beqz t0, restore_all 1481da177e4SLinus Torvalds andi t0, a2, _TIF_NEED_RESCHED 1491da177e4SLinus Torvalds bnez t0, work_resched 1501da177e4SLinus Torvalds 1511da177e4SLinus Torvaldswork_notifysig: # deal with pending signals and 1521da177e4SLinus Torvalds # notify-resume requests 1531da177e4SLinus Torvalds move a0, sp 1541da177e4SLinus Torvalds li a1, 0 1551da177e4SLinus Torvalds jal do_notify_resume # a2 already loaded 156c90e6fbbSDmitry Adamushko j resume_userspace_check 1571da177e4SLinus Torvalds 15802f884edSAl ViroFEXPORT(syscall_exit_partial) 15902f884edSAl Viro local_irq_disable # make sure need_resched doesn't 16002f884edSAl Viro # change between and return 16102f884edSAl Viro LONG_L a2, TI_FLAGS($28) # current->work 16202f884edSAl Viro li t0, _TIF_ALLWORK_MASK 16302f884edSAl Viro and t0, a2 16402f884edSAl Viro beqz t0, restore_partial 1651da177e4SLinus Torvalds SAVE_STATIC 166c2648527SThiemo Seufersyscall_exit_work: 167f76f3308SAl Viro LONG_L t0, PT_STATUS(sp) # returning to kernel mode? 168f76f3308SAl Viro andi t0, t0, KU_USER 169f76f3308SAl Viro beqz t0, resume_kernel 170c19c20acSRalf Baechle li t0, _TIF_WORK_SYSCALL_EXIT 171c2648527SThiemo Seufer and t0, a2 # a2 is preloaded with TI_FLAGS 172c2648527SThiemo Seufer beqz t0, work_pending # trace bit set? 1738b659a39SRalf Baechle local_irq_enable # could let syscall_trace_leave() 1741da177e4SLinus Torvalds # call schedule() instead 1751da177e4SLinus Torvalds move a0, sp 1768b659a39SRalf Baechle jal syscall_trace_leave 1771da177e4SLinus Torvalds b resume_userspace 178bce1a286SRalf Baechle 1796ebb496fSMarkos Chandras#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6) || \ 1806ebb496fSMarkos Chandras defined(CONFIG_MIPS_MT) 181bce1a286SRalf Baechle 182bce1a286SRalf Baechle/* 183bce1a286SRalf Baechle * MIPS32R2 Instruction Hazard Barrier - must be called 184bce1a286SRalf Baechle * 185bce1a286SRalf Baechle * For C code use the inline version named instruction_hazard(). 186bce1a286SRalf Baechle */ 187bce1a286SRalf BaechleLEAF(mips_ihb) 188bce1a286SRalf Baechle .set mips32r2 189bce1a286SRalf Baechle jr.hb ra 190bce1a286SRalf Baechle nop 191bce1a286SRalf Baechle END(mips_ihb) 192bce1a286SRalf Baechle 1936ebb496fSMarkos Chandras#endif /* CONFIG_CPU_MIPSR2 or CONFIG_CPU_MIPSR6 or CONFIG_MIPS_MT */ 194