diff options
Diffstat (limited to 'arch/mips/entry.S')
| -rw-r--r-- | arch/mips/entry.S | 665 |
1 files changed, 665 insertions, 0 deletions
diff --git a/arch/mips/entry.S b/arch/mips/entry.S new file mode 100644 index 000000000..ebf2c1d9c --- /dev/null +++ b/arch/mips/entry.S @@ -0,0 +1,665 @@ +/* + * linux/kernel/mips/sys_call.S + * + * Copyright (C) 1994 Waldorf GMBH + * written by Ralf Baechle + */ + +/* + * sys_call.S contains the system-call and fault low-level handling routines. + * This also contains the timer-interrupt handler, as well as all interrupts + * and faults that can result in a task-switch. + */ + +#define __ASSEMBLY__ + +#include <linux/sys.h> +#include <asm/segment.h> +#include <asm/mipsregs.h> +#include <asm/mipsconfig.h> +#include <asm/stackframe.h> +#include <asm/regdef.h> + +/* + * These are offsets into the task-struct. + */ +state = 0 +counter = 4 +priority = 8 +signal = 12 +blocked = 16 +flags = 20 +errno = 24 #/* MIPS OK */ +exec_domain = 60 #/* ??? */ + +ENOSYS = 38 + + .globl _system_call + .globl _lcall7 + .globl _device_not_available + .globl _coprocessor_error + .globl _divide_error + .globl _debug + .globl _nmi + .globl _int3 + .globl _overflow + .globl _bounds + .globl _invalid_op + .globl _double_fault + .globl _coprocessor_segment_overrun + .globl _invalid_TSS + .globl _segment_not_present + .globl _stack_segment + .globl _general_protection + .globl _reserved + .globl _alignment_check + .globl _page_fault + .globl ret_from_sys_call + .globl _sys_call_table + + .text + .set noreorder + .align 4 +handle_bottom_half: + lw s0,_intr_count + addiu s1,s0,1 + sw s1,_intr_count + mfc0 t0,CP0_STATUS # Enable IRQs + ori t0,t0,7 + xori t0,t0,6 + jal _do_bottom_half + mtc0 t0,CP0_STATUS + j 9f + sw s1,_intr_count + + .set reorder + .align 4 +reschedule: + la ra,ret_from_sys_call + j _schedule + + .set noreorder + .align 4 +_system_call: + li t1,NR_syscalls + bge t0,t1,ret_from_sys_call + .set nomacro + li t2,-ENOSYS # must be single instruction! + .set macro + lui t1,_sys_call_table + sll t0,t0,2 + addu t1,t0,t1 + lw t0,_sys_call_table(t1) + lw s0,_current + + beq zero,t0,ret_from_sys_call + lw t0,flags(s0) + sll t0,t0,2 # PF_TRACESYS + bltz t0,1f + sw zero,errno(s0) # delay slot + + jal t0 # do the real work + nop # fillme: delay slot + + sw v0,FR_REG2(sp) # save the return value + lw v0,errno(s0) + beq zero,v0,ret_from_sys_call + subu v0,zero,v0 # v0 = -v0 + # fixme: indicate error + j ret_from_sys_call + sw v0,FR_REG2(sp) + + .align 4 +1: jal _syscall_trace + nop +#if 0 + movl ORIG_EAX(%esp),%eax + call _sys_call_table(,%eax,4) + movl %eax,EAX(%esp) # save the return value + movl _current,%eax + movl errno(%eax),%edx + negl %edx + je 1f + movl %edx,EAX(%esp) + orl $(CF_MASK),EFLAGS(%esp) # set carry to indicate error +#endif +1: jal _syscall_trace + nop + + .align 4 +ret_from_sys_call: + lw t0,_intr_count # bottom half + bne zero,t0,2f + + lw t0,_bh_mask + lw t1,_bh_active + and t0,t0,t1 + bne zero,t0,handle_bottom_half +9: + mfc0 t0,CP0_STATUS # returning to supervisor ? + andi t0,t0,30 + subu t0,t0,6 + bltz t0,2f + +1: +#if 0 +/* + * Try whether this is needed or not... + */ + mfc0 t0,CP0_STATUS # enable irqs + ori t0,t0,0x7 + xori t0,t0,0x6 + mtc0 t0,CP0_STATUS +#endif + + lw t0,_need_resched + bne zero,t0,reschedule + + lw t0,_current + la t1,_task # task[0] cannot have signals + lw t2,state(s0) # state + beq t0,t1,2f + lw t0,counter(s0) # counter + beq zero,t2,reschedule # state == 0 ? + lw a0,blocked(s0) + # save blocked in a0 for + # signal handling + beq zero,t0,reschedule # counter == 0 ? + lw t0,signal(s0) + nor t1,zero,t0 + and t1,a0,t1 + beq zero,t1,skip_signal_return + nop +2: + jal _do_signal + move a1,sp + +skip_signal_return: + .set noreorder + .set noat +return: RESTORE_ALL + .set at + +/* + * Assumptions for _handle_int: + * - only bank a or b are possible interrupt sources + */ + .globl _handle_int +_handle_int: + .set noreorder + .text + la s0,PORT_BASE + li t1,0x0f + sb t1,0x20(s0) # poll command + lb t1,0x20(s0) # read result + FILL_LDS + bgtz t1,poll_second + andi t1,t1,7 + /* + * Acknowledge first pic + */ + lb t2,0x21(s0) + li s1,1 + sllv s1,s1,t1 + lb t4,_cache_21 + or t4,t4,s1 + sb t4,_cache_21 + sb t4,0x21(s0) + li t4,0x20 + sb t4,0x20(s0) + lw t0,_intr_count + addiu t0,t0,1 + sw t0,_intr_count + /* + * Now call the real handler + */ + la t0,_IRQ_vectors + sll t2,t1,2 + addu t0,t0,t2 + lw t0,(t0) + FILL_LDS + jalr t0 + nop + lw t0,_intr_count + subu t0,t0,1 + sw t0,_intr_count + /* + * Unblock first pic + */ +test1: lbu t1,0x21(s0) # tlbl exception?!? + lb t1,_cache_21 + nor s1,zero,s1 + and t1,t1,s1 + sb t1,_cache_21 + jr v0 + sb t1,0x21(s0) # delay slot + + .set at +poll_second: + li t1,0x0f + sb t1,0xa0(s0) # poll command + lb t1,0xa0(s0) # read result + FILL_LDS + bgtz t1,spurious_interrupt + andi t1,t1,7 + /* + * Acknowledge second pic + */ + lbu t2,0xa1(s0) + lbu t3,_cache_A1 + li s1,1 + sllv s1,s1,t1 + or t3,t3,s1 + sb t3,_cache_A1 + sb t3,0xa1(s0) + li t3,0x20 + sb t3,0xa0(s0) + lw t0,_intr_count + sb t3,0x20(s0) + addiu t0,t0,1 + sw t0,_intr_count + /* + * Now call the real handler + */ + la t0,_IRQ_vectors + sll t2,t1,2 + addu t0,t0,t2 + lw t0,32(t0) + FILL_LDS + jalr t0 + nop + lw t0,_intr_count + subu t0,t0,1 + sw t0,_intr_count + /* + * Unblock second pic + */ + lbu t1,0xa1(s0) + lb t1,_cache_A1 + nor s1,zero,s1 + and t1,t1,s1 + sb t1,_cache_A1 + jr v0 + sb t1,0xa1(s0) # delay slot + + .set at +spurious_interrupt: + /* + * Nothing happend... (whistle) + */ + lw t0,_spurious_count + la v0,return + addiu t0,t0,1 + sw t0,_spurious_count + jr ra + nop + + .globl _IRQ +_IRQ: move s2,ra + mfc0 t0,CP0_STATUS + ori t0,t0,0x1f + xori t0,t0,0x1e + mtc0 t0,CP0_STATUS + move a1,sp + jal _do_IRQ + move a0,t1 # Delay slot + mfc0 t0,CP0_STATUS + ori t0,t0,1 + xori t0,t0,1 + la v0,ret_from_sys_call + jr s2 + mtc0 t0,CP0_STATUS # Delay slot + + .globl _fast_IRQ +_fast_IRQ: move s2,ra + move a1,sp + jal _do_fast_IRQ + move a0,t1 # Delay slot + la v0,return + jr s2 + nop + + .globl _bad_IRQ +_bad_IRQ: + /* + * Don't return & unblock the pic + */ + j return + nop + + .bss + .globl _IRQ_vectors + +_IRQ_vectors: + .fill 16,4,0 + +/* + * Dummy handlers + */ + .text + .set noreorder + .set at + + .globl _handle_mod +_handle_mod: + la a0,mod_text + j _panic + nop + + .globl _handle_tlbl +_handle_tlbl: + la a0,badvaddr + mfc0 a1,CP0_BADVADDR + jal _printk + nop + la a0,status + lw a1,FR_STATUS(sp) + jal _printk + nop + la a0,eszero + move a1,s0 + jal _printk + nop + la a0,espe + move a1,sp + jal _printk + nop + la a0,jifftext + lw a1,_jiffies + jal _printk + nop + la a0,inttext + lw a1,_intr_count + jal _printk + nop + la a0,tlbl_msg + mfc0 a1,CP0_EPC + jal _printk + nop + la a0,tlbl_text + j _panic + nop + + .data +tlbl_msg: .asciz "tlbl exception at %x\n" +badvaddr: .asciz "accessing %x\n" +status: .asciz "cp0_status %x\n" +eszero: .asciz "s0 %x\n" +espe: .asciz "sp %x\n" +jifftext: .asciz "jiffies %d\n" +inttext: .asciz "IntNest: %d\n" + + .text + .globl _handle_tlbs +_handle_tlbs: + la a0,tlbs_text + j _panic + nop + + .globl _handle_adel +_handle_adel: + la v0,adel_text + jal _printk + nop + j _handle_tlbl + la a0,adel_text + j _panic + nop + + .globl _handle_ades +_handle_ades: + la a0,ades_text + j _panic + nop + + .globl _handle_ibe +_handle_ibe: + la a0,ibe_text + j _panic + nop + + .globl _handle_dbe +_handle_dbe: + la a0,dbe_text + j _panic + nop + + .globl _handle_sys +_handle_sys: + la a0,sys_text + j _panic + nop + + .globl _handle_bp +_handle_bp: + la a0,bp_text + j _panic + nop + + .globl _handle_ri +_handle_ri: + la a0,ri_text + j _panic + nop + + .globl _handle_cpu +_handle_cpu: + la a0,cpu_text + j _panic + nop + + .globl _handle_ov +_handle_ov: + la a0,ov_text + j _panic + nop + + .globl _handle_tr +_handle_tr: + la a0,tr_text + j _panic + nop + + .globl _handle_reserved +_handle_reserved: + la a0,reserved_text + j _panic + nop + + .globl _handle_fpe +_handle_fpe: + la a0,fpe_text + j _panic + nop + + .data +spurious_text: .asciz "Spurious interrupt" +fpe_text: .asciz "fpe exception" +reserved_text: .asciz "reserved exception" +tr_text: .asciz "tr exception" +ov_text: .asciz "ov exception" +cpu_text: .asciz "cpu exception" +ri_text: .asciz "ri exception" +bp_text: .asciz "bp exception" +sys_text: .asciz "sys exception" +dbe_text: .asciz "dbe exception" +ibe_text: .asciz "ibe exception" +ades_text: .asciz "ades exception" +adel_text: .asciz "adel exception" +tlbs_text: .asciz "tlbs exception" +mod_text: .asciz "mod exception" +tlbl_text: .asciz "tlbl exception" + +/* + * Exception handler table, 256 entries. + */ + .data + .globl _exception_handlers +_exception_handlers: + .word _handle_int /* 0 */ + .word _handle_mod + .word _handle_tlbl + .word _handle_tlbs + .word _handle_adel + .word _handle_ades + .word _handle_ibe + .word _handle_dbe + .word _handle_sys + .word _handle_bp + .word _handle_ri + .word _handle_cpu + .word _handle_ov + .word _handle_tr + .word _handle_reserved + .word _handle_fpe /* 15 */ +#if 0 + .fill 240,4,_handle_reserved +#endif + +/* + * Table of syscalls + */ + .data +_sys_call_table: + .word _sys_setup /* 0 */ + .word _sys_exit + .word _sys_fork + .word _sys_read + .word _sys_write + .word _sys_open /* 5 */ + .word _sys_close + .word _sys_waitpid + .word _sys_creat + .word _sys_link + .word _sys_unlink /* 10 */ + .word _sys_execve + .word _sys_chdir + .word _sys_time + .word _sys_mknod + .word _sys_chmod /* 15 */ + .word _sys_chown + .word _sys_break + .word _sys_stat + .word _sys_lseek + .word _sys_getpid /* 20 */ + .word _sys_mount + .word _sys_umount + .word _sys_setuid + .word _sys_getuid + .word _sys_stime /* 25 */ + .word _sys_ptrace + .word _sys_alarm + .word _sys_fstat + .word _sys_pause + .word _sys_utime /* 30 */ + .word _sys_stty + .word _sys_gtty + .word _sys_access + .word _sys_nice + .word _sys_ftime /* 35 */ + .word _sys_sync + .word _sys_kill + .word _sys_rename + .word _sys_mkdir + .word _sys_rmdir /* 40 */ + .word _sys_dup + .word _sys_pipe + .word _sys_times + .word _sys_prof + .word _sys_brk /* 45 */ + .word _sys_setgid + .word _sys_getgid + .word _sys_signal + .word _sys_geteuid + .word _sys_getegid /* 50 */ + .word _sys_acct + .word _sys_phys + .word _sys_lock + .word _sys_ioctl + .word _sys_fcntl /* 55 */ + .word _sys_mpx + .word _sys_setpgid + .word _sys_ulimit + .word _sys_olduname + .word _sys_umask /* 60 */ + .word _sys_chroot + .word _sys_ustat + .word _sys_dup2 + .word _sys_getppid + .word _sys_getpgrp /* 65 */ + .word _sys_setsid + .word _sys_sigaction + .word _sys_sgetmask + .word _sys_ssetmask + .word _sys_setreuid /* 70 */ + .word _sys_setregid + .word _sys_sigsuspend + .word _sys_sigpending + .word _sys_sethostname + .word _sys_setrlimit /* 75 */ + .word _sys_getrlimit + .word _sys_getrusage + .word _sys_gettimeofday + .word _sys_settimeofday + .word _sys_getgroups /* 80 */ + .word _sys_setgroups + .word _sys_select + .word _sys_symlink + .word _sys_lstat + .word _sys_readlink /* 85 */ + .word _sys_uselib + .word _sys_swapon + .word _sys_reboot + .word _sys_readdir + .word _sys_mmap /* 90 */ + .word _sys_munmap + .word _sys_truncate + .word _sys_ftruncate + .word _sys_fchmod + .word _sys_fchown /* 95 */ + .word _sys_getpriority + .word _sys_setpriority + .word _sys_profil + .word _sys_statfs + .word _sys_fstatfs /* 100 */ + .word _sys_ioperm + .word _sys_socketcall + .word _sys_syslog + .word _sys_setitimer + .word _sys_getitimer /* 105 */ + .word _sys_newstat + .word _sys_newlstat + .word _sys_newfstat + .word _sys_uname + .word _sys_iopl /* 110 */ + .word _sys_vhangup + .word _sys_idle + .word _sys_vm86 + .word _sys_wait4 + .word _sys_swapoff /* 115 */ + .word _sys_sysinfo + .word _sys_ipc + .word _sys_fsync + .word _sys_sigreturn + .word _sys_clone /* 120 */ + .word _sys_setdomainname + .word _sys_newuname + .word _sys_modify_ldt + .word _sys_adjtimex + .word _sys_mprotect /* 125 */ + .word _sys_sigprocmask + .word _sys_create_module + .word _sys_init_module + .word _sys_delete_module + .word _sys_get_kernel_syms /* 130 */ + .word _sys_quotactl + .word _sys_getpgid + .word _sys_fchdir + .word _sys_bdflush + .word _sys_sysfs /* 135 */ + .word _sys_personality + .word 0 /* for afs_syscall */ + .word _sys_setfsuid + .word _sys_setfsgid + .word _sys_llseek /* 140 */ + .space (NR_syscalls-140)*4 |