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[/] [or1k/] [trunk/] [rc203soc/] [sw/] [uClinux/] [arch/] [alpha/] [kernel/] [entry.S] - Rev 1765
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/** alpha/entry.S** kernel entry-points*/#include <linux/config.h>#include <asm/system.h>#define halt .long PAL_halt#define rti .long PAL_rti#define SIGCHLD 20#define NR_SYSCALLS 350#define osf_vfork sys_fork/** These offsets must match with "struct hae" in io.h:*/#define HAE_CACHE 0#define HAE_REG 8/** stack offsets*/#define SP_OFF 184#define SWITCH_STACK_SIZE 320/** task structure offsets*/#define TASK_STATE 0#define TASK_COUNTER 8#define TASK_PRIORITY 16#define TASK_SIGNAL 24#define TASK_BLOCKED 32#define TASK_FLAGS 40/** task flags (must match include/linux/sched.h):*/#define PF_PTRACED 0x00000010/** This defines the normal kernel pt-regs layout.** regs 9-15 preserved by C code* regs 16-18 saved by PAL-code* regs 29-30 saved and set up by PAL-code* JRP - Save regs 16-18 in a special area of the stack, so that* the palcode-provided values are available to the signal handler.*/#define SAVE_ALL \subq $30,184,$30; \stq $0,0($30); \stq $1,8($30); \stq $2,16($30); \stq $3,24($30); \stq $4,32($30); \stq $5,40($30); \stq $6,48($30); \stq $7,56($30); \stq $8,64($30); \stq $19,72($30); \stq $20,80($30); \stq $21,88($30); \stq $22,96($30); \stq $23,104($30); \stq $24,112($30); \stq $25,120($30); \stq $26,128($30); \stq $27,136($30); \stq $28,144($30); \lda $2,hae; \ldq $2,HAE_CACHE($2); \stq $2,152($30); \stq $16,160($30); \stq $17,168($30); \stq $18,176($30)#define RESTORE_ALL \lda $8,hae; \ldq $7,HAE_CACHE($8); \ldq $6,152($30); \subq $7,$6,$5; \beq $5,99f; \ldq $7,HAE_REG($8); \addq $31,7,$16; \call_pal PAL_swpipl; \stq $6,HAE_CACHE($8); \stq $6,0($7); \mb; \bis $0,$0,$16; \call_pal PAL_swpipl; \99:; \ldq $0,0($30); \ldq $1,8($30); \ldq $2,16($30); \ldq $3,24($30); \ldq $4,32($30); \ldq $5,40($30); \ldq $6,48($30); \ldq $7,56($30); \ldq $8,64($30); \ldq $19,72($30); \ldq $20,80($30); \ldq $21,88($30); \ldq $22,96($30); \ldq $23,104($30); \ldq $24,112($30); \ldq $25,120($30); \ldq $26,128($30); \ldq $27,136($30); \ldq $28,144($30); \addq $30,184,$30.text.set noat#if defined(__linux__) && !defined(__ELF__).set singlegp#endif.align 3.globl entInt.ent entIntentInt:SAVE_ALL/* start atomic operation with respect to software interrupts */lda $0,intr_countldq $1,0($0)addq $1,1,$1stq $1,0($0)/* set up the arguments to the C interrupt handler */lda $27,do_entIntjsr $26,($27),do_entInt/* ok, return */lda $0,intr_countldq $1,0($0)subq $1,1,$1stq $1,0($0)br $31,ret_from_sys_call.end entInt.align 3.globl entMM.ent entMMentMM:SAVE_ALLlda $27,do_page_faultlda $26,ret_from_sys_calljsr $31,($27),do_page_fault.end entMM.align 3.globl entArith.ent entArithentArith:SAVE_ALLlda $27,do_entArithlda $26,ret_from_sys_calljsr $31,($27),do_entArith.end entArith.align 3.globl entIF.ent entIFentIF:#ifdef CONFIG_KGDBbne $16,1f /* not a bpt trap -> *//** Call kgdb if it's enabled and if "current" is not being* traced or if we get a bpt in kernel mode (the architecture* manual defines the values of $17 and $18 as "unpredictable",* so they are fair game).*/lda $17,kgdb_enabledldl $17,0($17)beq $17,1f /* kgdb not enabled -> */#ifndef CONFIG_ALPHA_CABRIOLET/** MILO on Cabriolet doesn't seem to setup the PS in the* PALframe correctly. (davidm@azstarnet.com)*/ldq $18,0($30) /* get ps */and $18,8,$18beq $18,entKGDB#endiflda $17,current_setldq $17,0($17)bis $31,PF_PTRACED,$18ldq $17,TASK_FLAGS($17)and $17,$18,$17beq $17,entKGDB1:#endifSAVE_ALLlda $27,do_entIFlda $26,ret_from_sys_calljsr $31,($27),do_entIF.end entIF/** Fork() is one of the special system calls: it needs to* save the callee-saved regs so that the regs can be found* for the new process.. We save them in the "context switch"* stack format (see arch/alpha/kernel/process.c).** Also, for the kernel fork, we need to fake the system call* stack buildup, as we can't do system calls from kernel space.*/.align 3.ent kernel_clonekernel_clone:subq $30,6*8,$30stq $31,0($30)stq $26,8($30)stq $29,16($30)stq $16,24($30)stq $17,32($30)stq $18,40($30)bis $31,2,$0 /* Register v0: syscall nr for fork() */SAVE_ALLlda $27,sys_clonejsr $26,($27),sys_clonestq $0,0($30)br $31,ret_from_sys_call.end kernel_clone/** __kernel_thread(clone_flags, fn, arg)*/.align 3.globl __kernel_thread.ent __kernel_thread__kernel_thread:subq $30,4*8,$30stq $9,0($30)stq $10,8($30)stq $26,16($30)bis $17,$17,$9 /* save fn */bis $18,$18,$10 /* save arg */bsr $26,kernel_clonebne $20,1f /* $20 is non-zero in child */ldq $9,0($30)ldq $10,8($30)ldq $26,16($30)addq $30,4*8,$30ret $31,($26),1/* this is in child: look out as we don't have any stack here.. */1: bis $9,$9,$27 /* get fn */bis $10,$10,$16 /* get arg */jsr $26,($27)bis $0,$0,$16lda $27,sys_exitjsr $26,($27),sys_exitcall_pal PAL_halt.end __kernel_thread.align 3.ent do_switch_stackdo_switch_stack:lda $30,-SWITCH_STACK_SIZE($30)stq $9,0($30)stq $10,8($30)stq $11,16($30)stq $12,24($30)stq $13,32($30)stq $14,40($30)stq $15,48($30)stq $26,56($30)stt $f0,64($30)stt $f1,72($30)stt $f2,80($30)stt $f3,88($30)stt $f4,96($30)stt $f5,104($30)stt $f6,112($30)stt $f7,120($30)stt $f8,128($30)stt $f9,136($30)stt $f10,144($30)stt $f11,152($30)stt $f12,160($30)stt $f13,168($30)stt $f14,176($30)stt $f15,184($30)stt $f16,192($30)stt $f17,200($30)stt $f18,208($30)stt $f19,216($30)stt $f20,224($30)stt $f21,232($30)stt $f22,240($30)stt $f23,248($30)stt $f24,256($30)stt $f25,264($30)stt $f26,272($30)stt $f27,280($30)mf_fpcr $f0 # get fpcrstt $f28,288($30)stt $f29,296($30)stt $f30,304($30)stt $f0,312($30) # save fpcr in slot of $f31ret $31,($1),1.end do_switch_stack.align 3.ent undo_switch_stackundo_switch_stack:ldq $9,0($30)ldq $10,8($30)ldq $11,16($30)ldq $12,24($30)ldq $13,32($30)ldq $14,40($30)ldq $15,48($30)ldq $26,56($30)ldt $f30,312($30) # get saved fpcrldt $f0,64($30)ldt $f1,72($30)ldt $f2,80($30)ldt $f3,88($30)mt_fpcr $f30 # install saved fpcrldt $f4,96($30)ldt $f5,104($30)ldt $f6,112($30)ldt $f7,120($30)ldt $f8,128($30)ldt $f9,136($30)ldt $f10,144($30)ldt $f11,152($30)ldt $f12,160($30)ldt $f13,168($30)ldt $f14,176($30)ldt $f15,184($30)ldt $f16,192($30)ldt $f17,200($30)ldt $f18,208($30)ldt $f19,216($30)ldt $f20,224($30)ldt $f21,232($30)ldt $f22,240($30)ldt $f23,248($30)ldt $f24,256($30)ldt $f25,264($30)ldt $f26,272($30)ldt $f27,280($30)ldt $f28,288($30)ldt $f29,296($30)ldt $f30,304($30)lda $30,SWITCH_STACK_SIZE($30)ret $31,($1),1.end undo_switch_stack.align 3.globl entUna.ent entUnaentUna:lda $30,-256($30)stq $0,0($30)ldq $0,256($30) /* get PS */stq $1,8($30)stq $2,16($30)stq $3,24($30)and $0,8,$0 /* user mode? */stq $4,32($30)bne $0,entUnaUser /* yup -> do user-level unaligned fault */stq $5,40($30)stq $6,48($30)stq $7,56($30)stq $8,64($30)stq $9,72($30)stq $10,80($30)stq $11,88($30)stq $12,96($30)stq $13,104($30)stq $14,112($30)stq $15,120($30)/* 16-18 PAL-saved */stq $19,152($30)stq $20,160($30)stq $21,168($30)stq $22,176($30)stq $23,184($30)stq $24,192($30)stq $25,200($30)stq $26,208($30)stq $27,216($30)stq $28,224($30)stq $29,232($30)stq $30,240($30)stq $31,248($30)lda $27,do_entUnajsr $26,($27),do_entUnaldq $0,0($30)ldq $1,8($30)ldq $2,16($30)ldq $3,24($30)ldq $4,32($30)ldq $5,40($30)ldq $6,48($30)ldq $7,56($30)ldq $8,64($30)ldq $9,72($30)ldq $10,80($30)ldq $11,88($30)ldq $12,96($30)ldq $13,104($30)ldq $14,112($30)ldq $15,120($30)/* 16-18 PAL-saved */ldq $19,152($30)ldq $20,160($30)ldq $21,168($30)ldq $22,176($30)ldq $23,184($30)ldq $24,192($30)ldq $25,200($30)ldq $26,208($30)ldq $27,216($30)ldq $28,224($30)ldq $29,232($30)ldq $30,240($30)lda $30,256($30)rti.end entUna.align 3.ent entUnaUserentUnaUser:ldq $0,0($30) /* restore original $0 */lda $30,256($30) /* pop entUna's stack frame */SAVE_ALL /* setup normal kernel stack */lda $30,-56($30)stq $9,0($30)stq $10,8($30)stq $11,16($30)stq $12,24($30)stq $13,32($30)stq $14,40($30)stq $15,48($30)lda $27,do_entUnaUserbis $31,$30,$19jsr $26,($27),do_entUnaUserldq $9,0($30)ldq $10,8($30)ldq $11,16($30)ldq $12,24($30)ldq $13,32($30)ldq $14,40($30)ldq $15,48($30)lda $30,56($30)br $31,ret_from_sys_call.end entUnaUser/** A fork is the same as clone(SIGCHLD, 0);*/.align 3.globl sys_fork.ent sys_forksys_fork:bsr $1,do_switch_stackbis $31,SIGCHLD,$16bis $31,$31,$17bis $30,$30,$18lda $27,alpha_clonejsr $26,($27),alpha_clonebsr $1,undo_switch_stackret $31,($26),1.end sys_fork.align 3.globl sys_clone.ent sys_clonesys_clone:bsr $1,do_switch_stack/* arg1 and arg2 come from the user */bis $30,$30,$18lda $27,alpha_clonejsr $26,($27),alpha_clonebsr $1,undo_switch_stackret $31,($26),1.end sys_clone.align 3.globl alpha_switch_to.ent alpha_switch_toalpha_switch_to:bsr $1,do_switch_stackcall_pal PAL_swpctxbsr $1,undo_switch_stackret $31,($26),1.end alpha_switch_to/** Oh, well.. Disassembling OSF/1 binaries to find out how the* system calls work isn't much fun.** entSys is special in that the PAL-code doesn't save a0-a2, so* we start off by doing that by hand.*/.align 3.globl entSys.globl ret_from_sys_call.ent entSysentSys:stq $16,24($30)stq $17,32($30)stq $18,40($30)SAVE_ALL/* FIXME: optimize */lda $1,current_setldq $2,0($1)ldq $3,TASK_FLAGS($2)and $3,PF_PTRACED,$3bne $3,strace/* end of strace */lda $1,NR_SYSCALLS($31)lda $2,sys_call_tablelda $27,do_entSyscmpult $0,$1,$1s8addq $0,$2,$2beq $1,1fldq $27,0($2)1: jsr $26,($27),do_entSysblt $0,syscall_error /* the call failed */stq $0,0($30)stq $31,72($30) /* a3=0 => no error */.align 3ret_from_sys_call:cmovne $26,0,$19 /* $19 = 0 => non-restartable *//* check bottom half interrupts */lda $0,intr_countldq $1,0($0)bne $1,ret_from_handle_bhlda $2,bh_activeldq $3,0($2)lda $2,bh_maskldq $4,0($2)addq $1,1,$1and $3,$4,$2bne $2,handle_bottom_halfret_from_handle_bh:ldq $0,SP_OFF($30)and $0,8,$0beq $0,restore_allret_from_reschedule:lda $0,need_reschedlda $1,current_setldl $2,0($0)lda $4,init_taskldq $3,0($1)bne $2,reschedulesubq $4,$3,$4beq $4,restore_allldq $4,TASK_SIGNAL($3)ldq $16,TASK_BLOCKED($3)bic $4,$16,$4bne $4,signal_returnrestore_all:RESTORE_ALLrti/* PTRACE syscall handler */.align 3strace:/* set up signal stack, call syscall_trace */bsr $1,do_switch_stacklda $27,syscall_tracejsr $26,($27),syscall_tracebsr $1,undo_switch_stack/* get the system call number and the arguments back.. */ldq $0,0($30)ldq $16,SP_OFF+24($30)ldq $17,SP_OFF+32($30)ldq $18,SP_OFF+40($30)ldq $19,72($30)ldq $20,80($30)ldq $21,88($30)/* get the system call pointer.. */lda $1,NR_SYSCALLS($31)lda $2,sys_call_tablelda $27,do_entSyscmpult $0,$1,$1s8addq $0,$2,$2beq $1,1fldq $27,0($2)1: jsr $26,($27),do_entSys/* check return.. */blt $0,strace_error /* the call failed */stq $31,72($30) /* a3=0 => no error */strace_success:stq $0,0($30) /* save return value */bsr $1,do_switch_stacklda $27,syscall_tracejsr $26,($27),syscall_tracebsr $1,undo_switch_stackbr $31,ret_from_sys_call.align 3strace_error:ldq $19,0($30) /* old syscall nr (zero if success) */beq $19,strace_successldq $20,72($30) /* .. and this a3 */subq $31,$0,$0 /* with error in v0 */addq $31,1,$1 /* set a3 for errno return */stq $0,0($30)stq $1,72($30) /* a3 for return */bsr $1,do_switch_stackbis $19,$19,$9 /* save old syscall number */bis $20,$20,$10 /* save old a3 */lda $27,syscall_tracejsr $26,($27),syscall_tracebis $9,$9,$19bis $10,$10,$20bsr $1,undo_switch_stackbis $31,$31,$26 /* tell "ret_from_sys_call" that we can restart */br $31,ret_from_sys_call.align 3handle_bottom_half:/** We're called with $0 containing the address of* 'intr_count' and $1 containing 'intr_count+1'*/stq $1,0($0) /* intr_count = 1 */subq $30,16,$30stq $19,0($30) /* save syscall nr */stq $20,8($30) /* and error indication (a3) */lda $27,do_bottom_halfjsr $26,($27),do_bottom_halflda $0,intr_countldq $19,0($30)ldq $20,8($30)addq $30,16,$30stq $31,0($0) /* intr_count = 0 */br $31,ret_from_handle_bh.align 3syscall_error:/** Some system calls (e.g., ptrace) can return arbitrary* values which might normally be mistaken as error numbers.* Those functions must zero $0 (v0) directly in the stack* frame to indicate that a negative return value wasn't an* error number..*/ldq $19,0($30) /* old syscall nr (zero if success) */beq $19,ret_successldq $20,72($30) /* .. and this a3 */subq $31,$0,$0 /* with error in v0 */addq $31,1,$1 /* set a3 for errno return */bis $31,$31,$26 /* tell "ret_from_sys_call" that we can restart */stq $1,72($30) /* a3 for return */ret_success:stq $0,0($30)br $31,ret_from_sys_call.align 3signal_return:bis $30,$30,$17br $1,do_switch_stackbis $30,$30,$18lda $27,do_signaljsr $26,($27),do_signallda $30,SWITCH_STACK_SIZE($30)br $31,restore_all.end entSys.align 3.ent reschedulereschedule:subq $30,16,$30stq $19,0($30) /* save syscall nr */stq $20,8($30) /* and error indication (a3) */lda $27,schedulejsr $26,($27),scheduleldq $19,0($30)ldq $20,8($30)addq $30,16,$30br $31,ret_from_reschedule.end reschedule.align 3.ent sys_sigreturnsys_sigreturn:bis $30,$30,$17lda $30,-SWITCH_STACK_SIZE($30)bis $30,$30,$18lda $27,do_sigreturnjsr $26,($27),do_sigreturnbr $1,undo_switch_stackbr $31,ret_from_sys_call.end sys_sigreturn.align 3.ent sys_sigsuspendsys_sigsuspend:bis $30,$30,$17br $1,do_switch_stackbis $30,$30,$18lda $27,do_sigsuspendjsr $26,($27),do_sigsuspendlda $30,SWITCH_STACK_SIZE($30)br $31,ret_from_sys_call.end sys_sigsuspend.align 3.globl sys_call_tablesys_call_table:/*0*/ .quad do_entSys, sys_exit, sys_fork, sys_read, sys_write.quad do_entSys, sys_close, sys_wait4, do_entSys, sys_link.quad sys_unlink, do_entSys, sys_chdir, sys_fchdir, sys_mknod.quad sys_chmod, sys_chown, sys_brk, do_entSys, sys_lseek.quad sys_getxpid, osf_mount, osf_umount, sys_setuid, sys_getxuid.quad do_entSys, sys_ptrace, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, sys_access, do_entSys.quad do_entSys, sys_sync, sys_kill, do_entSys, sys_setpgid.quad do_entSys, sys_dup, sys_pipe, do_entSys, do_entSys.quad sys_open, do_entSys, sys_getxgid, osf_sigprocmask, do_entSys/*50*/ .quad do_entSys, sys_acct, sys_sigpending, do_entSys, sys_ioctl.quad do_entSys, do_entSys, sys_symlink, sys_readlink, sys_execve.quad sys_umask, sys_chroot, do_entSys, sys_getpgrp, sys_getpagesize.quad do_entSys, osf_vfork, sys_newstat, sys_newlstat, do_entSys.quad do_entSys, osf_mmap, do_entSys, sys_munmap, sys_mprotect.quad sys_madvise, sys_vhangup, do_entSys, do_entSys, sys_getgroups/* map BSD's setpgrp to sys_setpgid for binary compatibility: */.quad sys_setgroups, do_entSys, sys_setpgid, sys_setitimer, do_entSys.quad do_entSys, sys_getitimer, sys_gethostname, sys_sethostname, sys_getdtablesize.quad sys_dup2, sys_newfstat, sys_fcntl, sys_select, do_entSys.quad sys_fsync, sys_setpriority, sys_socket, sys_connect, sys_accept/*100*/ .quad osf_getpriority, sys_send, sys_recv, sys_sigreturn, sys_bind.quad sys_setsockopt, sys_listen, do_entSys, do_entSys, do_entSys.quad do_entSys, sys_sigsuspend, do_entSys, sys_recvmsg, sys_sendmsg.quad do_entSys, sys_gettimeofday, sys_getrusage, sys_getsockopt, do_entSys.quad sys_readv, sys_writev, sys_settimeofday, sys_fchown, sys_fchmod.quad sys_recvfrom, sys_setreuid, sys_setregid, sys_rename, sys_truncate.quad sys_ftruncate, sys_flock, sys_setgid, sys_sendto, sys_shutdown.quad sys_socketpair, sys_mkdir, sys_rmdir, sys_utimes, do_entSys.quad do_entSys, sys_getpeername, do_entSys, do_entSys, sys_getrlimit.quad sys_setrlimit, do_entSys, sys_setsid, sys_quotactl, do_entSys/*150*/ .quad sys_getsockname, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, sys_sigaction, do_entSys, do_entSys, osf_getdirentries.quad osf_statfs, osf_fstatfs, do_entSys, do_entSys, do_entSys.quad osf_getdomainname, sys_setdomainname, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, osf_swapon/*200*/ .quad sys_msgctl, sys_msgget, sys_msgrcv, sys_msgsnd, sys_semctl.quad sys_semget, sys_semop, osf_utsname, do_entSys, osf_shmat.quad sys_shmctl, sys_shmdt, sys_shmget, do_entSys, do_entSys.quad do_entSys, do_entSys, sys_msync, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, sys_getpgid, sys_getsid.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, osf_proplist_syscall.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys/*250*/ .quad do_entSys, osf_usleep_thread, do_entSys, do_entSys, sys_sysfs.quad do_entSys, osf_getsysinfo, osf_setsysinfo, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys.quad do_entSys, do_entSys, do_entSys, do_entSys, do_entSys/* linux-specific system calls start at 300 *//*300*/ .quad sys_bdflush, sys_sethae, sys_mount, sys_adjtimex, sys_swapoff.quad sys_getdents, alpha_create_module, sys_init_module, sys_delete_module, sys_get_kernel_syms.quad sys_syslog, sys_reboot, sys_clone, sys_uselib, sys_mlock.quad sys_munlock, sys_mlockall, sys_munlockall, sys_sysinfo, sys_sysctl.quad sys_idle, sys_umount, sys_swapon, sys_times, sys_personality.quad sys_setfsuid, sys_setfsgid, sys_ustat, sys_statfs, sys_fstatfs.quad sys_sched_setparam, sys_sched_getparam, sys_sched_setscheduler, sys_sched_getscheduler, sys_sched_yield.quad sys_sched_get_priority_max, sys_sched_get_priority_min, sys_sched_rr_get_interval, do_entSys /* sys_afs_syscall */, sys_newuname.quad sys_nanosleep, sys_mremap, do_entSys, do_entSys, do_entSys.quad sys_pciconfig_read, sys_pciconfig_write, do_entSys, do_entSys, do_entSys#ifdef CONFIG_KGDB#define KGDB_STACK_SIZE (8*1024).lcomm kgdb_stack_bottom, KGDB_STACK_SIZE/** The following is the nasty part of entering KGDB. GDB assumes that* it can access the memory below the interrupted thread's stack* pointer (SP). This means that the stub cannot run on this stack* (interrupts could overwrite changes made by GDB). Similarly, we do* not want to bother the GDB user with the call chain leading from* the interrupt handler to this function. That is, the SP reported* to GDB should be the thread's SP at the point it was interrupted. We* achieve all this by switching to KGDB's own stack before saving any* registers (of course, the PAL-generated frame is already on the stack and* we copy that part explicitly). GDB does whatever it wants to the* thread's stack; and when it continues execution, we restore the* registers from the private stack and return from the interrupt.** This is not re-entrant---gdb on the host probably would get confused* anyway, but we probably ought to detect that case at the least...*/.align 3.globl entKGDB.ent entKGDBentKGDB:lda $16,kgdb_stack_bottomlda $16,(KGDB_STACK_SIZE-48)($16)bis $31,$30,$17 /* save real sp in a1 */bis $31,$16,$30 /* update sp atomically! */SAVE_ALL /* save regular stuff *//** Only now can we disable interrupts (swpipl may step on* t0,t8..t11, and a0):*/bis $31,7,$16call_pal PAL_swpipl/* copy PAL frame to kgdb stack: */ldq $1,0($17)ldq $2,8($17)ldq $3,16($17)ldq $4,24($17)ldq $5,32($17)ldq $6,40($17)stq $1,0+184($30)stq $2,8+184($30)stq $3,16+184($30)stq $4,24+184($30)stq $5,32+184($30)stq $6,40+184($30)/* allocate space for and save caller saved regs as well as orig sp: */lda $30,-320($30)addq $17,48,$17 /* pop PAL frame */stq $17,0($30) /* save original sp */stq $9,0x08($30); stq $10,0x10($30); stq $11,0x18($30)stq $12,0x20($30); stq $13,0x28($30); stq $14,0x30($30)stq $15,0x38($30)stt $f0,0x40($30); stt $f1,0x48($30); stt $f2,0x50($30); stt $f3,0x58($30)stt $f4,0x60($30); stt $f5,0x68($30); stt $f6,0x70($30); stt $f7,0x78($30)stt $f8,0x80($30); stt $f9,0x88($30); stt $f10,0x90($30); stt $f11,0x98($30)stt $f12,0xa0($30); stt $f13,0xa8($30); stt $f14,0xb0($30); stt $f15,0xb8($30)stt $f16,0xc0($30); stt $f17,0xc8($30); stt $f18,0xd0($30); stt $f19,0xd8($30)stt $f20,0xe0($30); stt $f21,0xe8($30); stt $f22,0xf0($30); stt $f23,0xf8($30)stt $f24,0x100($30); stt $f25,0x108($30); stt $f26,0x110($30); stt $f27,0x118($30)stt $f28,0x120($30); stt $f29,0x128($30); stt $f30,0x130($30); stt $f31,0x138($30)bis $31,$30,$16lda $27,kgdb_handle_exceptionjsr $26,($27),kgdb_handle_exceptionldq $17,0($30) /* load new sp and caller-saved registers */ldq $9,0x08($30); ldq $10,0x10($30); ldq $11,0x18($30)ldq $12,0x20($30); ldq $13,0x28($30); ldq $14,0x30($30)ldq $15,0x38($30)ldt $f0,0x40($30); ldt $f1,0x48($30); ldt $f2,0x50($30); ldt $f3,0x58($30)ldt $f4,0x60($30); ldt $f5,0x68($30); ldt $f6,0x70($30); ldt $f7,0x78($30)ldt $f8,0x80($30); ldt $f9,0x88($30); ldt $f10,0x90($30); ldt $f11,0x98($30)ldt $f12,0xa0($30); ldt $f13,0xa8($30); ldt $f14,0xb0($30); ldt $f15,0xb8($30)ldt $f16,0xc0($30); ldt $f17,0xc8($30); ldt $f18,0xd0($30); ldt $f19,0xd8($30)ldt $f20,0xe0($30); ldt $f21,0xe8($30); ldt $f22,0xf0($30); ldt $f23,0xf8($30)ldt $f24,0x100($30); ldt $f25,0x108($30); ldt $f26,0x110($30); ldt $f27,0x118($30)ldt $f28,0x120($30); ldt $f29,0x128($30); ldt $f30,0x130($30); ldt $f31,0x138($30)lda $30,320($30) /* pop extra register frame *//** Copy PAL frame from kgdb stack to new stack so we can rti* to it:*/ldq $1,0+184($30)ldq $2,8+184($30)ldq $3,16+184($30)ldq $4,24+184($30)ldq $5,32+184($30)ldq $6,40+184($30)subq $17,48,$17 /* alloc space for PAL frame on new stack */stq $1,0($17)stq $2,8($17)stq $3,16($17)stq $4,24($17)stq $5,32($17)stq $6,40($17)RESTORE_ALLbis $31,$17,$30 /* establish new sp */rti.end entKGDB#endif /* CONFIG_KGDB */