NetBSD/sys/arch/powerpc/ibm4xx/4xx_locore.S

410 lines
11 KiB
ArmAsm

/* $NetBSD: 4xx_locore.S,v 1.1 2002/08/23 11:37:55 scw Exp $ */
/*
* Copyright 2001 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc.
*
* 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 for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
* 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.
*/
/*
* This is not a standalone file. To use it, #inlcude it at
* the end of your port's locore.S
*/
/*
* Taken straight from Walnut's locore.S, with the following attribution:
* $OpenBSD: locore.S,v 1.4 1997/01/26 09:06:38 rahnds Exp $
*/
/*
* No processes are runnable, so loop waiting for one.
* Separate label here for accounting purposes.
* When we get here, interrupts are off (MSR[EE]=0) and sched_lock is held.
*/
ASENTRY(Idle)
lis 8,_C_LABEL(sched_whichqs)@ha
lwz 9,_C_LABEL(sched_whichqs)@l(8)
or. 9,9,9
bne- .Lsw1 /* at least one queue non-empty */
wrteei 1 /* reenable ints again */
/* May do some power saving here? */
/* Check if we can use power saving mode */
lis 8,_C_LABEL(powersave)@ha
lwz 9,_C_LABEL(powersave)@l(8)
or. 9,9,9
beq 1f
/* TODO: Enter power saving mode here */
1:
wrteei 0 /* disable interrupts while manipulating runque */
b _ASM_LABEL(Idle)
/*
* switchexit gets called from cpu_exit to complete the exit procedure.
*/
ENTRY(switchexit)
/* First switch to the idle pcb/kernel stack */
lis 6,idle_u@ha
lwz 6,idle_u@l(6)
lis 7,_C_LABEL(curpcb)@ha
stw 6,_C_LABEL(curpcb)@l(7)
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 _C_LABEL(exit2)
/* 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
lis 3,_C_LABEL(curproc)@ha
xor 31,31,31
stw 31,_C_LABEL(curproc)@l(3) /* Zero to not accumulate cpu time */
lis 3,_C_LABEL(curpcb)@ha
lwz 31,_C_LABEL(curpcb)@l(3)
xor 3,3,3
bl _C_LABEL(lcsplx)
stw 3,PCB_SPL(31) /* save spl */
wrteei 0 /* disable interrupts while manipulating runque */
/* Find a new process */
lis 8,_C_LABEL(sched_whichqs)@ha
lwz 9,_C_LABEL(sched_whichqs)@l(8)
or. 9,9,9
beq- _ASM_LABEL(Idle) /* all queues empty */
.Lsw1:
cntlzw 10,9
lis 4,_C_LABEL(sched_qs)@ha
addi 4,4,_C_LABEL(sched_qs)@l
slwi 3,10,3
add 3,3,4 /* select queue */
lwz 31,P_FORW(3) /* unlink first proc from queue */
lwz 4,P_FORW(31)
stw 4,P_FORW(3)
stw 3,P_BACK(4)
cmpl 0,3,4 /* queue empty? */
bne 1f
lis 3,0x80000000@h
srw 3,3,10
andc 9,9,3
stw 9,_C_LABEL(sched_whichqs)@l(8) /* mark it empty */
1:
/* just did this resched thing */
xor 3,3,3
lis 4,_C_LABEL(want_resched)@ha
stw 3,_C_LABEL(want_resched)@l(4)
stw 3,P_BACK(31) /* probably superfluous */
/* Process now running on a processor. */
li 3,SONPROC /* p->p_stat = SONPROC */
stb 3,P_STAT(31)
/* record new process */
lis 4,_C_LABEL(curproc)@ha
stw 31,_C_LABEL(curproc)@l(4)
wrteei 1 /* Now we can interrupt again */
cmpl 0,31,30 /* is it the same process? */
beq switch_return
or. 30,30,30 /* old process was exiting? */
beq switch_exited
#ifndef PPC_IBM4XX
mfsr 10,USER_SR /* save USER_SR for copyin/copyout */
#else
li 10,0 /* no SR for 4xx CPUs */
#endif
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:
wrteei 0 /* disable interrupts while actually switching */
/* indicate new pcb */
lwz 4,P_ADDR(31)
lis 5,_C_LABEL(curpcb)@ha
stw 4,_C_LABEL(curpcb)@l(5)
/* save real pmap pointer for spill fill */
lwz 5,PCB_PMR(4)
lis 6,_C_LABEL(curpm)@ha
stwu 5,_C_LABEL(curpm)@l(6)
stwcx. 5,0,6 /* clear possible reservation */
/* Switch to the new virtual space */
/* Do not have to do anything here. TLB PID gets updated on return from trap. */
lwz 1,PCB_SP(4) /* get new procs SP */
wrteei 1 /* interrupts are okay again */
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
switch_return:
mr 30,7 /* save proc pointer */
lwz 3,PCB_SPL(4)
bl _C_LABEL(lcsplx)
0:
lis 3,_C_LABEL(curpm)@ha
addi 3,3,_C_LABEL(curpm)@l /* Do we need a context? */
lwz 4,PM_CTX(3)
cmpwi 4,0
# mtspr SPR_SPR0,4 /* Always keep the current ctx here */
mr 3,30
bne 1f
bl _C_LABEL(ctx_alloc)
mr 3,30 /* get curproc for special fork
returns */
b 0b /* Reload */
1:
lwz 31,12(1)
lwz 30,8(1)
addi 1,1,16
lwz 0,4(1)
mtlr 0
blr
/*
* Child comes here at the end of a fork.
* Return to userspace via the trap return path.
*/
.globl _C_LABEL(fork_trampoline)
_C_LABEL(fork_trampoline):
xor 3,3,3
bl _C_LABEL(lcsplx)
mtlr 31
mr 3,30
blrl /* jump indirect to r31 */
b trapexit
/*
* Pull in common trap vector code.
*/
#include <powerpc/ibm4xx/trap_subr.S>
#include <powerpc/ibm4xx/4xx_trap_subr.S>
/*
* int setfault()
*
* Similar to setjmp to setup for handling faults on accesses to user memory.
* Any routine using this may only call bcopy, either the form below,
* or the (currently used) C code optimized, so it doesn't use any non-volatile
* registers.
*/
.globl _C_LABEL(setfault)
_C_LABEL(setfault):
mflr 0
mfcr 12
lis 4,_C_LABEL(curpcb)@ha
lwz 4,_C_LABEL(curpcb)@l(4)
stw 3,PCB_FAULT(4)
stw 0,0(3)
stw 1,4(3)
stw 2,8(3)
stmw 12,12(3)
xor 3,3,3
blr
.globl _C_LABEL(ppc4xx_reset)
_C_LABEL(ppc4xx_reset):
mfspr 3,SPR_DBCR0
oris 3,r13,DBCR0_RST_SYSTEM@h
mtspr SPR_DBCR0,3
ba 0
#if 0
/*
* XXXX the following doesn't quite work right yet.
*/
/*
* void bcopy(const void *src, void *dst, size_t len);
*
* swap r3 and r4 and fall through to memcopy.
*/
.globl _C_LABEL(bcopy)
_C_LABEL(bcopy):
mr r0,r3
mr r3,r4
mr r4,r0
/* FALLTHROUGH */
/*
* void * memcpy(void *dst (r3), const void *src (r4), size_t len (r5));
*
* Copy memory (obviously)
*
* We will try to do data cache block aligned stores so we
* can use block allocate and not have to read from the
* destination.
*
* Register use:
*
* r1 stack (of course)
* r3 dst
* r4 src
* r5 len
* r6 tmp
* r7 holds 32
* r8 holds dst
* r24-r31 block move regs
*
*/
ENTRY(memcpy)
stwu r1,-(10*4)(r1) /* Allocate some RAM to save 8 regs to. */
cmpwi r5, 32 /* Less than 32 bytes ? */
stmw r24,8(r1) /* Save ALL regs (could be optimized) */
mr r8,r3 /* save dst */
li r7,32
dcbt 0,r4 /* Start bringing in cache line. */
blt 1f /* Finish up */
neg r6,r3 /* Find how far unaligned we are... */
andi. r6,r6,31 /* Cache-align dest. */
mtxer r6
sub r5,r5,r6 /* subtract count */
lswx r24,0,r4 /* Load some. */
add r4,r4,r6
dcbt 0,r4 /* Fetch next line */
stswx r24,0,r3 /* Store some */
add r3,r3,r6
addic. r6,r5,-32 /* Pre-decrement next line */
ble 1f /* Less than 32-bytes? finishup */
/* Dest should not be cache line aligned. */
/* XXX need gas 2.11 to grok dcba insn */
#ifdef GAS_2_11
dcba 0,r3 /* Allocate a line */
#else
.long 0x7c001dec /* dcba 0,r3 */
#endif
0:
dcbt r7,r4 /* Bring in the next line, too */
lswi r24,r4,32
addi r4,r4,32 /* Inc src */
mr r5,r6
addic. r6,r5,-32
stswi r24,r3,32
addi r3,r3,32 /* Inc dst */
#ifdef GAS_2_11
dcba 0,r3 /* Allocate another line */
#else
.long 0x7c071dec /* dcba r7,r3 */
#endif
bgt 0b
1:
mtxer r5 /* Store byte count */
lswx r24,0,r4 /* Load up to 32 bytes */
stswx r24,0,r3 /* Store up to 32 bytes */
mr r3,r8 /* Return dst */
lmw r24,8(r1)
addi r1,r1,(10*4)
blr
#endif