swtch64.S revision 183088
1/* $FreeBSD: head/sys/powerpc/aim/swtch.S 183088 2008-09-16 17:03:52Z marcel $ */
2/* $NetBSD: locore.S,v 1.24 2000/05/31 05:09:17 thorpej Exp $ */
3
4/*-
5 * Copyright (C) 2001 Benno Rice
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY Benno Rice ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
25 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
26 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27*/
28/*-
29 * Copyright (C) 1995, 1996 Wolfgang Solfrank.
30 * Copyright (C) 1995, 1996 TooLs GmbH.
31 * All rights reserved.
32 *
33 * Redistribution and use in source and binary forms, with or without
34 * modification, are permitted provided that the following conditions
35 * are met:
36 * 1. Redistributions of source code must retain the above copyright
37 *    notice, this list of conditions and the following disclaimer.
38 * 2. Redistributions in binary form must reproduce the above copyright
39 *    notice, this list of conditions and the following disclaimer in the
40 *    documentation and/or other materials provided with the distribution.
41 * 3. All advertising materials mentioning features or use of this software
42 *    must display the following acknowledgement:
43 *	This product includes software developed by TooLs GmbH.
44 * 4. The name of TooLs GmbH may not be used to endorse or promote products
45 *    derived from this software without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
48 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
49 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
50 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
51 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
52 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
53 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
54 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
55 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
56 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
57 */
58
59#include "assym.s"
60
61#include <sys/syscall.h>
62
63#include <machine/trap.h>
64#include <machine/param.h>
65#include <machine/sr.h>
66#include <machine/psl.h>
67#include <machine/asm.h>
68
69/*
70 * void cpu_throw(struct thread *old, struct thread *new)
71 */
72ENTRY(cpu_throw)
73	mr	%r15, %r4
74	b	cpu_switchin
75
76/*
77 * void cpu_switch(struct thread *old,
78 *		   struct thread *new,
79 *		   struct mutex *mtx);
80 *
81 * Switch to a new thread saving the current state in the old thread.
82 */
83ENTRY(cpu_switch)
84	stw	%r5,TD_LOCK(%r3)	/* ULE:	update old thread's lock */
85					/* XXX needs to change for MP */
86
87	lwz	%r5,TD_PCB(%r3)		/* Get the old thread's PCB ptr */
88	mr	%r12,%r2
89	stmw	%r12,PCB_CONTEXT(%r5)	/* Save the non-volatile GP regs.
90					   These can now be used for scratch */
91
92	mfcr	%r16			/* Save the condition register */
93	stw	%r16,PCB_CR(%r5)
94	mflr	%r16			/* Save the link register */
95	stw	%r16,PCB_LR(%r5)
96	mfsr	%r16,USER_SR		/* Save USER_SR for copyin/out */
97	isync
98	stw	%r16,PCB_AIM_USR(%r5)
99	stw	%r1,PCB_SP(%r5)		/* Save the stack pointer */
100
101	mr	%r14,%r3		/* Copy the old thread ptr... */
102	mr	%r15,%r4		/* and the new thread ptr in scratch */
103
104	lwz	%r6,PCB_FLAGS(%r5)
105	/* Save FPU context if needed */
106	andi.	%r6, %r6, PCB_FPU
107	beq	.L1
108	bl	save_fpu
109	mr	%r3,%r14		/* restore old thread ptr */
110.L1:
111	bl	pmap_deactivate		/* Deactivate the current pmap */
112
113cpu_switchin:
114	mfsprg	%r7,0			/* Get the pcpu pointer */
115	stw	%r15,PC_CURTHREAD(%r7)	/* Store new current thread */
116	lwz	%r17,TD_PCB(%r15)	/* Store new current PCB */
117	stw	%r17,PC_CURPCB(%r7)
118
119	mr	%r3,%r15		/* Get new thread ptr */
120	bl	pmap_activate		/* Activate the new address space */
121
122	lwz	%r6, PCB_FLAGS(%r17)
123	/* Restore FPU context if needed */
124	andi.	%r6, %r6, PCB_FPU
125	beq	.L2
126	mr	%r3,%r15		/* Pass curthread to enable_fpu */
127	bl	enable_fpu
128
129	/* thread to restore is in r3 */
130.L2:
131	mr	%r3,%r17		/* Recover PCB ptr */
132	lmw	%r12,PCB_CONTEXT(%r3)	/* Load the non-volatile GP regs */
133	mr	%r2,%r12
134	lwz	%r5,PCB_CR(%r3)		/* Load the condition register */
135	mtcr	%r5
136	lwz	%r5,PCB_LR(%r3)		/* Load the link register */
137	mtlr	%r5
138	lwz	%r5,PCB_AIM_USR(%r3)	/* Load the USER_SR segment reg */
139	mtsr	USER_SR,%r5
140	isync
141	lwz	%r1,PCB_SP(%r3)		/* Load the stack pointer */
142	blr
143
144/*
145 * savectx(pcb)
146 * Update pcb, saving current processor state
147 */
148ENTRY(savectx)
149	mr	%r12,%r2
150	stmw	%r12,PCB_CONTEXT(%r3)	/* Save the non-volatile GP regs */
151	mfcr	%r4			/* Save the condition register */
152	stw	%r4,PCB_CONTEXT(%r3)
153	blr
154
155/*
156 * fork_trampoline()
157 * Set up the return from cpu_fork()
158 */
159ENTRY(fork_trampoline)
160	lwz	%r3,CF_FUNC(%r1)
161	lwz	%r4,CF_ARG0(%r1)
162	lwz	%r5,CF_ARG1(%r1)
163	bl	fork_exit
164	addi	%r1,%r1,CF_SIZE-FSP	/* Allow 8 bytes in front of
165					   trapframe to simulate FRAME_SETUP
166					   does when allocating space for
167					   a frame pointer/saved LR */
168	b	trapexit
169