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/* $OpenBSD: process.S,v 1.1 2004/04/21 15:24:13 aoyama Exp $ */
/*
* Copyright (c) 1996 Nivas Madhur
* 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 Nivas Madhur.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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.h"
#include <machine/asm.h>
#include <machine/psl.h>
#include <machine/intr.h>
data
align 4
ASLOCAL(swchanpanic)
string "switch wchan %x\0"
align 4
ASLOCAL(swsrunpanic)
string "switch SRUN %x\0"
#ifdef DEBUG
align 4
ASLOCAL(boguspsr)
string "Invalid PSR in idle loop 0x%x\n\0"
#endif
text
align 8
ASLOCAL(Lswchanpanic)
or.u r2, r0, hi16(_ASM_LABEL(swchanpanic))
or r2, r2, lo16(_ASM_LABEL(swchanpanic))
bsr.n _C_LABEL(panic)
or r3, r0, r9
ASLOCAL(Lswsrunpanic)
or.u r2, r0, hi16(_ASM_LABEL(swsrunpanic))
or r2, r2, lo16(_ASM_LABEL(swsrunpanic))
bsr.n _C_LABEL(panic)
or r3, r0, r9
/*
* At exit of a process, do a cpu_switch for the last time.
* The mapping of the pcb at p->p_addr has already been deleted,
* and the memory for the pcb+stack has been freed.
* The ipl is high enough to prevent the memory from being reallocated.
* switch_exit(proc * p)
*/
ENTRY(switch_exit)
/*
* Change pcb to idle u. area, i.e., set r31 to top of stack
* and set curpcb to point to _idle_u. r2 contains proc *p.
*/
or.u r30, r0, hi16(_C_LABEL(idle_u))
or r30, r30,lo16(_C_LABEL(idle_u))
addu r31, r30, USIZE /* now on idle_u stack */
or.u r10, r0, hi16(_C_LABEL(curpcb))
st r30, r10,lo16(_C_LABEL(curpcb)) /* curpcb = &idle_u */
or.u r10, r0, hi16(_C_LABEL(curproc))
st r0, r10, lo16(_C_LABEL(curproc)) /* curproc = NULL */
/* Schedule the vmspace and stack to be freed. */
bsr.n _C_LABEL(exit2)
subu r31, r31, 48 /* allocate stack */
addu r31, r31, 48 /* restore stack */
bsr _C_LABEL(cpu_switch) /* goto final switch */
/*
* cpu_switch()
* XXX - Arg 1 is a proc pointer (curproc) but this doesn't use it.
* XXX - how about using stack for saving spl and last proc?
* XXX rewrite this whole mess in C nivas
*/
ENTRY(cpu_switch)
/*
* Save state of previous process in its pcb.
*/
or.u r2, r0, hi16(_C_LABEL(curpcb))
ld r2, r2, lo16(_C_LABEL(curpcb))
st r1, r2, PCB_PC /* save return address */
bsr _ASM_LABEL(__savectx)
/* note that we don't need to recover r1 at this point */
or.u r11, r0, hi16(_C_LABEL(curproc))
ld r2, r11, lo16(_C_LABEL(curproc))
bcnd eq0, r2, 1f
bsr.n _C_LABEL(pmap_deactivate)
subu r31, r31,48
addu r31, r31,48
or.u r11, r0, hi16(_C_LABEL(curproc))
1:
st r0, r11, lo16(_C_LABEL(curproc)) /* curproc = NULL */
ASLOCAL(Lidleloop)
/*
* Find the highest-priority queue that isn't empty,
* then take the first proc from that queue.
*/
or.u r7, r0, hi16(_C_LABEL(whichqs))
ld r7, r7, lo16(_C_LABEL(whichqs))
bcnd ne0, r7, _ASM_LABEL(Ldoneloop)
ASLOCAL(Lloopchk) /* if whichqs is zero, keep checking */
bsr.n _C_LABEL(setipl) /* unmask all ints... */
or r2, r0, IPL_NONE
ldcr r2, PSR
bb0 PSR_INTERRUPT_DISABLE_BIT, r2, 1f
#ifdef DEBUG
or r3, r2, r0
or.u r2, r0, hi16(_ASM_LABEL(boguspsr))
bsr.n _C_LABEL(printf)
or r2, r2, lo16(_ASM_LABEL(boguspsr))
ldcr r2, PSR
#endif
clr r2, r2, 1<PSR_INTERRUPT_DISABLE_BIT> /* ...and enable them */
stcr r2, PSR
FLUSH_PIPELINE
1:
br _ASM_LABEL(Lidleloop)
ASLOCAL(Ldoneloop)
bsr.n _C_LABEL(setipl) /* disable ints */
or r2, r0, IPL_HIGH
or.u r7, r0, hi16(_C_LABEL(whichqs)) /* reload whichqs */
ld r7, r7, lo16(_C_LABEL(whichqs))
bcnd eq0, r7, _ASM_LABEL(Lloopchk) /* keep spinning for whichqs to be != 0 */
xor r6, r6, r6 /* set r6 to 0 */
1: bb1 0, r7, 2f /* if rightmost bit set, done */
extu r7, r7, 0<1> /* else, right shift whichqs, */
br.n 1b /* increment r6, and repeat */
addu r6, r6, 1
2:
or.u r7, r0, hi16(_qs)
or r7, r7, lo16(_qs)
/*
* Need to make
* p->p_forw->p_back = p->p_back and
* p->p_back->p_forw = p->p_forw where
* p is q->p_forw.
* Remember that q->p_forw == p and p->p_back == q.
*/
lda.d r8, r7[r6] /* r8 = &qs[ff1(whichqs)] */
ld r9, r8, P_FORW /* r8 is q, r9 is p */
ld r12, r9, P_FORW /* r12 = p->p_forw */
st r8, r12, P_BACK /* p->p_forw->p_back = q (p->p_back) */
st r12, r8, P_FORW /* q->p_forw = p->p_forw */
lda.d r8, r7[r6] /* reload r8 with qs[ff1(whichqs)] */
ld r12, r8, P_FORW /* q->p_forw */
cmp r12, r12, r8 /* q == q->p_forw; anyone left on queue? */
bb1 ne, r12, 3f /* yes, skip clearing bit in whichqs */
or r12, r0, 1 /* r12 is 1 now */
1: bcnd eq0, r6, 2f
mak r12, r12, 0<1> /* shift left by 1 */
br.n 1b
subu r6, r6, 1 /* keep doing this while r6 != 0 */
2:
/*
* NOTE: we could have just used "mak r12, r12, r6" instead of the
* loop above. But that will break if NQS is made > 32. I can use
* preprocessor to do the right thing, but that means I have to
* include sys/proc.h in this file. XXX nivas
*/
or.u r7, r0, hi16(_C_LABEL(whichqs))
ld r8, r7, lo16(_C_LABEL(whichqs))
and.c r8, r8, r12 /* whichqs &= ~the bit */
st r8, r7, lo16(_C_LABEL(whichqs))
3:
ld r2, r9, P_WCHAN
bcnd ne0, r2, _ASM_LABEL(Lswchanpanic)
ld.b r2, r9, P_STAT
cmp r2, r2, SRUN
bb1 ne, r2, _ASM_LABEL(Lswsrunpanic)
or.u r11, r0, hi16(_C_LABEL(want_resched))
st r0, r11, lo16(_C_LABEL(want_resched)) /* clear want_resched */
or.u r11, r0, hi16(_C_LABEL(curproc))
st r9, r11,lo16(_C_LABEL(curproc)) /* curproc = p */
/* r9 is curproc */
st r0, r9, P_BACK /* p->p_back = 0 */
ld r3, r9, P_ADDR
or.u r10, r0, hi16(_C_LABEL(curpcb))
st r3, r10, lo16(_C_LABEL(curpcb)) /* curpcb = p->p_addr */
/* pmap_activate() the process' pmap */
or r2, r0, r9 /* r2 = p */
or r14, r0, r9 /* save p in r14 */
bsr.n _C_LABEL(pmap_activate)
subu r31, r31,48
addu r31, r31,48
or r9, r0, r14 /* restore p saved in r14 */
or.u r31, r0, hi16(_ASM_LABEL(intstack_end))
or r31,r31, lo16(_ASM_LABEL(intstack_end))
subu r31, r31,48
bsr.n _C_LABEL(load_u_area)
or r2, r0, r9
addu r31, r31,48
or.u r10, r0, hi16(_C_LABEL(curpcb))
ld r10, r10, lo16(_C_LABEL(curpcb))
/* XXX Is this correct/necessary? */
st r10, r14, P_ADDR /* p->p_addr = curpcb; restore p_addr */
/* restore from the current context */
ld r2, r10, PCB_FCR62
ld r3, r10, PCB_FCR63
fstcr r2, fcr62
fstcr r3, fcr63
ld r1, r10, PCB_PC
ld r14,r10, PCB_R14
ld r15,r10, PCB_R15
ld r16,r10, PCB_R16
ld r17,r10, PCB_R17
ld r18,r10, PCB_R18
ld r19,r10, PCB_R19
ld r20,r10, PCB_R20
ld r21,r10, PCB_R21
ld r22,r10, PCB_R22
ld r23,r10, PCB_R23
ld r24,r10, PCB_R24
ld r25,r10, PCB_R25
ld r26,r10, PCB_R26
ld r27,r10, PCB_R27
ld r28,r10, PCB_R28
ld r29,r10, PCB_R29
ld r30,r10, PCB_R30 /* restore frame pointer & stack */
ld r31,r10, PCB_SP
/* XXX
* Should we postpone restoring stack till after ipl is restored?
* The stack access could fault
*/
subu r31,r31,48
st r1, r31,36 /* save r1 on stack */
bsr.n _C_LABEL(setipl)
ld r2, r10, PCB_IPL /* restore interrupt mask */
ld r1, r31,36 /* restore r1 from stack */
addu r31,r31,48
jmp.n r1
or r2, r0, 1 /* return 1 (for alternate returns) */
/*
* savectx(pcb)
* Update pcb, saving current processor state.
*/
ENTRY(savectx)
/*
* Save preserved general register set.
*/
st r1, r2, PCB_PC /* save return address */
ASENTRY(__savectx)
st r14, r2, PCB_R14
st r15, r2, PCB_R15
st r16, r2, PCB_R16
st r17, r2, PCB_R17
st r18, r2, PCB_R18
st r19, r2, PCB_R19
st r20, r2, PCB_R20
st r21, r2, PCB_R21
st r22, r2, PCB_R22
st r23, r2, PCB_R23
st r24, r2, PCB_R24
st r25, r2, PCB_R25
st r26, r2, PCB_R26
st r27, r2, PCB_R27
st r28, r2, PCB_R28
st r29, r2, PCB_R29
st r30, r2, PCB_R30 /* save frame pointer & stack pointer */
st r31, r2, PCB_SP
/*
* Get the current spl.
* We need to save r1 on the stack because we don't know if we were
* called as savectx or __savectx.
*/
subu r31, r31, 40 /* allocate stack for r1 and args */
st r1, r31, 32
bsr.n _C_LABEL(getipl) /* get the current interrupt mask */
or r14, r0, r2
st r2, r14, PCB_IPL /* save interrupt mask */
ld r1, r31, 32 /* recover return address */
addu r31, r31, 40 /* put stack pointer back */
/*
* Save FP state.
*/
fldcr r2, fcr62
fldcr r3, fcr63
st r2, r14, PCB_FCR62
jmp.n r1
st r3, r14, PCB_FCR63
|
