misc.s

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

	addi	r4,r4,-4
	li	r5,4

#ifndef CONFIG_8xx
#if MAX_L1_COPY_PREFETCH > 1
	li	r0,MAX_L1_COPY_PREFETCH
	li	r11,4
	mtctr	r0
11:	dcbt	r11,r4
	addi	r11,r11,L1_CACHE_LINE_SIZE
	bdnz	11b
#else /* MAX_L1_COPY_PREFETCH == 1 */
	dcbt	r5,r4
	li	r11,L1_CACHE_LINE_SIZE+4
#endif /* MAX_L1_COPY_PREFETCH */
#endif /* CONFIG_8xx */

	li	r0,4096/L1_CACHE_LINE_SIZE
	mtctr	r0
1:
#ifndef CONFIG_8xx
	dcbt	r11,r4
	dcbz	r5,r3
#endif
	COPY_16_BYTES
#if L1_CACHE_LINE_SIZE >= 32
	COPY_16_BYTES
#if L1_CACHE_LINE_SIZE >= 64
	COPY_16_BYTES
	COPY_16_BYTES
#if L1_CACHE_LINE_SIZE >= 128
	COPY_16_BYTES
	COPY_16_BYTES
	COPY_16_BYTES
	COPY_16_BYTES
#endif
#endif
#endif
	bdnz	1b
	blr

/*
 * Atomic [test&set] exchange
 *
 *	unsigned long xchg_u32(void *ptr, unsigned long val)
 * Changes the memory location '*ptr' to be val and returns
 * the previous value stored there.
 */
_GLOBAL(xchg_u32)
	mr	r5,r3		/* Save pointer */
10:	lwarx	r3,0,r5		/* Fetch old value & reserve */
	stwcx.	r4,0,r5		/* Update with new value */
	bne-	10b		/* Retry if "reservation" (i.e. lock) lost */
	blr

/*
 * void atomic_clear_mask(atomic_t mask, atomic_t *addr)
 * void atomic_set_mask(atomic_t mask, atomic_t *addr);
 */
_GLOBAL(atomic_clear_mask)
10:	lwarx	r5,0,r4
	andc	r5,r5,r3
	stwcx.	r5,0,r4
	bne-	10b
	blr
_GLOBAL(atomic_set_mask)
10:	lwarx	r5,0,r4
	or	r5,r5,r3
	stwcx.	r5,0,r4
	bne-	10b
	blr

/*
 * I/O string operations
 *
 * insb(port, buf, len)
 * outsb(port, buf, len)
 * insw(port, buf, len)
 * outsw(port, buf, len)
 * insl(port, buf, len)
 * outsl(port, buf, len)
 * insw_ns(port, buf, len)
 * outsw_ns(port, buf, len)
 * insl_ns(port, buf, len)
 * outsl_ns(port, buf, len)
 *
 * The *_ns versions don't do byte-swapping.
 */
_GLOBAL(_insb)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,1
	blelr-
00:	lbz	r5,0(r3)
	eieio
	stbu	r5,1(r4)
	bdnz	00b
	blr

_GLOBAL(_outsb)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,1
	blelr-
00:	lbzu	r5,1(r4)
	stb	r5,0(r3)
	eieio
	bdnz	00b
	blr	

_GLOBAL(_insw)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,2
	blelr-
00:	lhbrx	r5,0,r3
	eieio
	sthu	r5,2(r4)
	bdnz	00b
	blr

_GLOBAL(_outsw)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,2
	blelr-
00:	lhzu	r5,2(r4)
	eieio
	sthbrx	r5,0,r3	
	bdnz	00b
	blr	

_GLOBAL(_insl)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,4
	blelr-
00:	lwbrx	r5,0,r3
	eieio
	stwu	r5,4(r4)
	bdnz	00b
	blr

_GLOBAL(_outsl)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,4
	blelr-
00:	lwzu	r5,4(r4)
	stwbrx	r5,0,r3
	eieio
	bdnz	00b
	blr	

_GLOBAL(ide_insw)
_GLOBAL(_insw_ns)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,2
	blelr-
00:	lhz	r5,0(r3)
	eieio
	sthu	r5,2(r4)
	bdnz	00b
	blr

_GLOBAL(ide_outsw)
_GLOBAL(_outsw_ns)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,2
	blelr-
00:	lhzu	r5,2(r4)
	sth	r5,0(r3)
	eieio
	bdnz	00b
	blr	

_GLOBAL(_insl_ns)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,4
	blelr-
00:	lwz	r5,0(r3)
	eieio
	stwu	r5,4(r4)
	bdnz	00b
	blr

_GLOBAL(_outsl_ns)
	cmpwi	0,r5,0
	mtctr	r5
	subi	r4,r4,4
	blelr-
00:	lwzu	r5,4(r4)
	stw	r5,0(r3)
	eieio
	bdnz	00b
	blr	

/*
 * Extended precision shifts.
 * 
 * Updated to be valid for shift counts from 0 to 63 inclusive.
 * -- Gabriel
 *
 * R3/R4 has 64 bit value
 * R5    has shift count
 * result in R3/R4
 *
 *  ashrdi3: arithmetic right shift (sign propagation)	    
 *  lshrdi3: logical right shift	
 *  ashldi3: left shift
 */
_GLOBAL(__ashrdi3)
	subfic	r6,r5,32	
	srw	r4,r4,r5	# LSW = count > 31 ? 0 : LSW >> count
	addi	r7,r5,32	# could be xori, or addi with -32
	slw	r6,r3,r6	# t1 = count > 31 ? 0 : MSW << (32-count)
	rlwinm	r8,r7,0,32	# t3 = (count < 32) ? 32 : 0
	sraw	r7,r3,r7	# t2 = MSW >> (count-32)
	or	r4,r4,r6	# LSW |= t1
	slw	r7,r7,r8	# t2 = (count < 32) ? 0 : t2
	sraw	r3,r3,r5	# MSW = MSW >> count
	or	r4,r4,r7	# LSW |= t2
	blr

_GLOBAL(__ashldi3)
	subfic	r6,r5,32	
	slw	r3,r3,r5	# MSW = count > 31 ? 0 : MSW << count
	addi	r7,r5,32	# could be xori, or addi with -32
	srw	r6,r4,r6	# t1 = count > 31 ? 0 : LSW >> (32-count)
	slw	r7,r4,r7	# t2 = count < 32 ? 0 : LSW << (count-32)
	or	r3,r3,r6	# MSW |= t1
	slw	r4,r4,r5	# LSW = LSW << count
	or	r3,r3,r7	# MSW |= t2
	blr

_GLOBAL(__lshrdi3)
	subfic	r6,r5,32	
	srw	r4,r4,r5	# LSW = count > 31 ? 0 : LSW >> count
	addi	r7,r5,32	# could be xori, or addi with -32
	slw	r6,r3,r6	# t1 = count > 31 ? 0 : MSW << (32-count)
	srw	r7,r3,r7	# t2 = count < 32 ? 0 : MSW >> (count-32)
	or	r4,r4,r6	# LSW |= t1
	srw	r3,r3,r5	# MSW = MSW >> count
	or	r4,r4,r7	# LSW |= t2 
	blr

_GLOBAL(abs)
	srawi	r4,r3,31
	xor	r3,r3,r4
	sub	r3,r3,r4
	blr

_GLOBAL(_get_SP)
	mr	r3,r1		/* Close enough */
	blr
	
/*
 * These are used in the alignment trap handler when emulating
 * single-precision loads and stores.
 * We restore and save the fpscr so the task gets the same result
 * and exceptions as if the cpu had performed the load or store.
 */

#if defined(CONFIG_4xx)
_GLOBAL(cvt_fd)
	lfs	0,0(r3)
	stfd	0,0(r4)
	blr

_GLOBAL(cvt_df)
	lfd	0,0(r3)
	stfs	0,0(r4)
	blr
#else
_GLOBAL(cvt_fd)
	lfd	0,-4(r5)	/* load up fpscr value */
	mtfsf	0xff,0
	lfs	0,0(r3)
	stfd	0,0(r4)
	mffs	0		/* save new fpscr value */
	stfd	0,-4(r5)
	blr

_GLOBAL(cvt_df)
	lfd	0,-4(r5)	/* load up fpscr value */
	mtfsf	0xff,0
	lfd	0,0(r3)
	stfs	0,0(r4)
	mffs	0		/* save new fpscr value */
	stfd	0,-4(r5)
	blr
#endif

/*
 * Create a kernel thread
 *   kernel_thread(fn, arg, flags)
 */
_GLOBAL(kernel_thread)
	mr	r6,r3		/* function */
	ori	r3,r5,CLONE_VM	/* flags */
	li	r0,__NR_clone
	sc
	cmpi	0,r3,0		/* parent or child? */
	bnelr			/* return if parent */
	li	r0,0		/* make top-level stack frame */
	stwu	r0,-16(r1)
	mtlr	r6              /* fn addr in lr */
	mr	r3,r4	        /* load arg and call fn */
	blrl
	li	r0,__NR_exit	/* exit after child exits */
	li	r3,0
	sc

/*
 * This routine is just here to keep GCC happy - sigh...
 */	
_GLOBAL(__main)
	blr

#define SYSCALL(name) \
_GLOBAL(name) \
	li	r0,__NR_##name; \
	sc; \
	bnslr; \
	lis	r4,errno@ha; \
	stw	r3,errno@l(r4); \
	li	r3,-1; \
	blr

#define __NR__exit __NR_exit

SYSCALL(sync)
SYSCALL(setsid)
SYSCALL(write)
SYSCALL(dup)
SYSCALL(execve)
SYSCALL(open)
SYSCALL(close)
SYSCALL(waitpid)
SYSCALL(fork)
SYSCALL(delete_module)
SYSCALL(_exit)
SYSCALL(lseek)
SYSCALL(read)

/* Why isn't this a) automatic, b) written in 'C'? */	
	.data
	.align 4
_GLOBAL(sys_call_table)
	.long sys_ni_syscall	/* 0  -  old "setup()" system call */
	.long sys_exit
	.long sys_fork
	.long sys_read
	.long sys_write
	.long sys_open		/* 5 */
	.long sys_close
	.long sys_waitpid
	.long sys_creat
	.long sys_link
	.long sys_unlink	/* 10 */
	.long sys_execve
	.long sys_chdir
	.long sys_time
	.long sys_mknod
	.long sys_chmod		/* 15 */
	.long sys_lchown
	.long sys_ni_syscall			/* old break syscall holder */
	.long sys_stat
	.long sys_lseek
	.long sys_getpid	/* 20 */
	.long sys_mount
	.long sys_oldumount
	.long sys_setuid
	.long sys_getuid
	.long sys_stime		/* 25 */
	.long sys_ptrace
	.long sys_alarm
	.long sys_fstat
	.long sys_pause
	.long sys_utime		/* 30 */
	.long sys_ni_syscall			/* old stty syscall holder */
	.long sys_ni_syscall			/* old gtty syscall holder */
	.long sys_access
	.long sys_nice
	.long sys_ni_syscall	/* 35 */	/* old ftime syscall holder */
	.long sys_sync
	.long sys_kill
	.long sys_rename
	.long sys_mkdir
	.long sys_rmdir		/* 40 */
	.long sys_dup
	.long sys_pipe
	.long sys_times
	.long sys_ni_syscall			/* old prof syscall holder */
	.long sys_brk		/* 45 */
	.long sys_setgid
	.long sys_getgid
	.long sys_signal
	.long sys_geteuid
	.long sys_getegid	/* 50 */
	.long sys_acct
	.long sys_umount			/* recycled never used phys() */
	.long sys_ni_syscall			/* old lock syscall holder */
	.long sys_ioctl
	.long sys_fcntl		/* 55 */
	.long sys_ni_syscall			/* old mpx syscall holder */
	.long sys_setpgid
	.long sys_ni_syscall			/* old ulimit syscall holder */
	.long sys_olduname
	.long sys_umask		/* 60 */
	.long sys_chroot
	.long sys_ustat
	.long sys_dup2
	.long sys_getppid
	.long sys_getpgrp	/* 65 */
	.long sys_setsid
	.long sys_sigaction
	.long sys_sgetmask
	.long sys_ssetmask
	.long sys_setreuid	/* 70 */
	.long sys_setregid
	.long sys_sigsuspend
	.long sys_sigpending
	.long sys_sethostname
	.long sys_setrlimit	/* 75 */
	.long sys_old_getrlimit
	.long sys_getrusage
	.long sys_gettimeofday
	.long sys_settimeofday
	.long sys_getgroups	/* 80 */
	.long sys_setgroups
	.long ppc_select
	.long sys_symlink
	.long sys_lstat
	.long sys_readlink	/* 85 */
	.long sys_uselib
	.long sys_swapon
	.long sys_reboot
	.long old_readdir
	.long sys_mmap		/* 90 */
	.long sys_munmap
	.long sys_truncate
	.long sys_ftruncate
	.long sys_fchmod
	.long sys_fchown	/* 95 */
	.long sys_getpriority
	.long sys_setpriority
	.long sys_ni_syscall			/* old profil syscall holder */
	.long sys_statfs
	.long sys_fstatfs	/* 100 */
	.long sys_ioperm
	.long sys_socketcall
	.long sys_syslog
	.long sys_setitimer
	.long sys_getitimer	/* 105 */
	.long sys_newstat
	.long sys_newlstat
	.long sys_newfstat
	.long sys_uname
	.long sys_iopl		/* 110 */
	.long sys_vhangup
	.long sys_ni_syscall	/* old 'idle' syscall */
	.long sys_vm86
	.long sys_wait4
	.long sys_swapoff	/* 115 */
	.long sys_sysinfo
	.long sys_ipc
	.long sys_fsync
	.long sys_sigreturn
	.long sys_clone		/* 120 */
	.long sys_setdomainname
	.long sys_newuname
	.long sys_modify_ldt
	.long sys_adjtimex
	.long sys_mprotect	/* 125 */
	.long sys_sigprocmask
	.long sys_create_module
	.long sys_init_module
	.long sys_delete_module
	.long sys_get_kernel_syms	/* 130 */
	.long sys_quotactl
	.long sys_getpgid
	.long sys_fchdir
	.long sys_bdflush
	.long sys_sysfs		/* 135 */
	.long sys_personality
	.long sys_ni_syscall	/* for afs_syscall */
	.long sys_setfsuid
	.long sys_setfsgid
	.long sys_llseek	/* 140 */
	.long sys_getdents
	.long ppc_select
	.long sys_flock
	.long sys_msync
	.long sys_readv		/* 145 */
	.long sys_writev
	.long sys_getsid
	.long sys_fdatasync
	.long sys_sysctl
	.long sys_mlock		/* 150 */
	.long sys_munlock
	.long sys_mlockall
	.long sys_munlockall
	.long sys_sched_setparam
	.long sys_sched_getparam	/* 155 */
	.long sys_sched_setscheduler
	.long sys_sched_getscheduler
	.long sys_sched_yield
	.long sys_sched_get_priority_max
	.long sys_sched_get_priority_min  /* 160 */
	.long sys_sched_rr_get_interval
	.long sys_nanosleep
	.long sys_mremap
	.long sys_setresuid
	.long sys_getresuid	/* 165 */
	.long sys_query_module
	.long sys_poll
	.long sys_nfsservctl
	.long sys_setresgid
	.long sys_getresgid	/* 170 */
	.long sys_prctl
	.long sys_rt_sigreturn
	.long sys_rt_sigaction
	.long sys_rt_sigprocmask	
	.long sys_rt_sigpending	/* 175 */
	.long sys_rt_sigtimedwait
	.long sys_rt_sigqueueinfo
	.long sys_rt_sigsuspend
	.long sys_pread
	.long sys_pwrite	/* 180 */
	.long sys_chown
	.long sys_getcwd
	.long sys_capget
	.long sys_capset
	.long sys_sigaltstack	/* 185 */
	.long sys_sendfile
	.long sys_ni_syscall		/* streams1 */
	.long sys_ni_syscall		/* streams2 */
	.long sys_vfork
	.long sys_getrlimit	/* 190 */
	.long sys_readahead
	.long sys_mmap2	
	.long sys_truncate64
	.long sys_ftruncate64
	.long sys_stat64	/* 195 */
	.long sys_lstat64
	.long sys_fstat64
	.long sys_pciconfig_read
	.long sys_pciconfig_write 
	.long sys_pciconfig_iobase 	/* 200 */
	.long sys_ni_syscall		/* 201 - reserved - MacOnLinux - new */
	.long sys_getdents64
	.long sys_pivot_root
	.long sys_fcntl64
	.long sys_madvise	/* 205 */
	.long sys_mincore
	.long sys_gettid
	.rept NR_syscalls-(.-sys_call_table)/4
		.long sys_ni_syscall
	.endr