freebsd-skq/sys/powerpc/aim/swtch.S
Benno Rice f9bac91b18 Bring in NetBSD code used in the PowerPC port.
Reviewed by:	obrien, dfr
Obtained from:	NetBSD
2001-06-10 02:39:37 +00:00

250 lines
6.7 KiB
ArmAsm

/* $FreeBSD$ */
/* $NetBSD: locore.S,v 1.24 2000/05/31 05:09:17 thorpej Exp $ */
/*
* Copyright (C) 2001 Benno Rice
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY Benno Rice ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (C) 1995, 1996 Wolfgang Solfrank.
* Copyright (C) 1995, 1996 TooLs GmbH.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by TooLs GmbH.
* 4. The name of TooLs GmbH may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "assym.s"
#include <sys/syscall.h>
#include <machine/trap.h>
#include <machine/param.h>
#include <machine/pmap.h>
#include <machine/psl.h>
#include <machine/asm.h>
/*
* Some instructions gas doesn't understand (yet?)
*/
#define bdneq bdnzf 2,
/*
* No processes are runnable, so loop waiting for one.
* Separate label here for accounting purposes.
*/
#if 0 /* XXX: I think this is now unneeded. Leaving it in just in case. */
ASENTRY(Idle)
mfmsr 3
andi. 3,3,~PSL_EE@l /* disable interrupts while
manipulating runque */
mtmsr 3
lis 8,sched_whichqs@ha
lwz 9,sched_whichqs@l(8)
or. 9,9,9
bne- .Lsw1 /* at least one queue non-empty */
ori 3,3,PSL_EE@l /* reenable ints again */
mtmsr 3
isync
/* Check if we can use power saving mode */
lis 8,powersave@ha
lwz 9,powersave@l(8)
or. 9,9,9
beq 1f
sync
oris 3,3,PSL_POW@h /* enter power saving mode */
mtmsr 3
isync
1:
b _ASM_LABEL(Idle)
#endif /* XXX */
/*
* switchexit gets called from cpu_exit to complete the exit procedure.
*/
ENTRY(switchexit)
/* First switch to the idle pcb/kernel stack */
#if 0 /* XXX */
lis 6,idle_u@ha
lwz 6,idle_u@l(6)
mfsprg 7,0
stw 6,GD_CURPCB(7)
#endif
addi 1,6,USPACE-16 /* 16 bytes are reserved at stack top */
/*
* Schedule the vmspace and stack to be freed (the proc arg is
* already in r3).
*/
bl sys_exit
/* Fall through to cpu_switch to actually select another proc */
li 3,0 /* indicate exited process */
/*
* void cpu_switch(struct proc *p)
* Find a runnable process and switch to it.
*/
/* XXX noprofile? --thorpej@netbsd.org */
ENTRY(cpu_switch)
mflr 0 /* save lr */
stw 0,4(1)
stwu 1,-16(1)
stw 31,12(1)
stw 30,8(1)
mr 30,3
mfsprg 3,0
xor 31,31,31
stw 31,GD_CURPROC(3) /* Zero to not accumulate cpu time */
mfsprg 3,0
lwz 31,GD_CURPCB(3)
xor 3,3,3
#if 0 /* XXX */
bl lcsplx
#endif
stw 3,PCB_SPL(31) /* save spl */
/* Find a new process */
bl chooseproc
1:
/* just did this resched thing */
xor 3,3,3
lis 4,want_resched@ha
stw 3,want_resched@l(4)
/* record new process */
mfsprg 4,0
stw 3,GD_CURPROC(4)
cmpl 0,31,30 /* is it the same process? */
beq switch_return
or. 30,30,30 /* old process was exiting? */
beq switch_exited
mfsr 10,USER_SR /* save USER_SR for copyin/copyout */
mfcr 11 /* save cr */
mr 12,2 /* save r2 */
stwu 1,-SFRAMELEN(1) /* still running on old stack */
stmw 10,8(1)
lwz 3,P_ADDR(30)
stw 1,PCB_SP(3) /* save SP */
switch_exited:
mfmsr 3
andi. 3,3,~PSL_EE@l /* disable interrupts while
actually switching */
mtmsr 3
/* indicate new pcb */
lwz 4,P_ADDR(31)
mfsprg 5,0
stw 4,GD_CURPCB(5)
#if 0 /* XXX */
/* save real pmap pointer for spill fill */
lwz 5,PCB_PMR(4)
lis 6,curpm@ha
stwu 5,curpm@l(6)
stwcx. 5,0,6 /* clear possible reservation */
#endif
addic. 5,5,64
li 6,0
mfsr 8,KERNEL_SR /* save kernel SR */
1:
addis 6,6,-0x10000000@ha /* set new procs segment registers */
or. 6,6,6 /* This is done from the real
address pmap */
lwzu 7,-4(5) /* so we don't have to worry */
mtsrin 7,6 /* about accessibility */
bne 1b
mtsr KERNEL_SR,8 /* restore kernel SR */
isync
lwz 1,PCB_SP(4) /* get new procs SP */
ori 3,3,PSL_EE@l /* interrupts are okay again */
mtmsr 3
lmw 10,8(1) /* get other regs */
lwz 1,0(1) /* get saved SP */
mr 2,12 /* get saved r2 */
mtcr 11 /* get saved cr */
isync
mtsr USER_SR,10 /* get saved USER_SR */
isync
switch_return:
mr 30,7 /* save proc pointer */
lwz 3,PCB_SPL(4)
#if 0 /* XXX */
bl lcsplx
#endif
mr 3,30 /* get curproc for special fork
returns */
lwz 31,12(1)
lwz 30,8(1)
addi 1,1,16
lwz 0,4(1)
mtlr 0
blr
/*
* Fake savectx for the time being.
*/
ENTRY(savectx)
blr