swtch64.S revision 99659
1/* $FreeBSD: head/sys/powerpc/aim/swtch.S 99659 2002-07-09 12:57:23Z benno $ */
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_switch()
71 * Find a runnable thread and switch to it.
72 */
73ENTRY(cpu_switch)
74	mfsprg	%r3,0			/* Get the pcpu pointer */
75	lwz	%r4,PC_CURTHREAD(%r3)	/* Get the current thread */
76	lwz	%r3,TD_PCB(%r4)		/* Get a pointer to the PCB */
77
78	mr	%r12,%r2
79	stmw	%r12,PCB_CONTEXT(%r3)	/* Save the non-volatile GP regs */
80	mr	%r14,%r3		/* Copy the current pcb pointer */
81	mr	%r15,%r4		/* ... and the curthread pointer */
82	mfcr	%r16			/* Save the condition register */
83	stw	%r16,PCB_CR(%r3)
84	mflr	%r16			/* Save the link register */
85	stw	%r16,PCB_LR(%r3)
86	stw	%r1,PCB_SP(%r3)		/* Save the stack pointer */
87
88#if 0
89	lwz	%r29,PCB_FLAGS(%r3)
90	andi.	%r9, %r29, 1		/* XXX - don't hard code */
91	beq	.L1
92	bl	save_fpu
93#endif
94
95.L1:
96	bl	choosethread		/* Find a new thread to run */
97	cmplw	0,%r3,%r15		/* Compare to curthread */
98	beq	.L2			/* If it's the same, we're done */
99
100	mr	%r16,%r3		/* Save off the (struct thread *) */
101
102	mr	%r3,%r15
103	bl	pmap_deactivate		/* Deactivate the current pmap */
104
105	mr	%r3,%r16
106	bl	pmap_activate		/* Activate the new address space */
107
108	mfsprg	%r4,0			/* Get the pcpu pointer */
109	stw	%r16,PC_CURTHREAD(%r4)	/* Store new current thread */
110	mr	%r3,%r16		/*   and save in r3 */
111	lwz	%r16,TD_PCB(%r16)	/* Store new current PCB */
112	stw	%r16,PC_CURPCB(%r4)
113
114#if 0
115	lwz	%r29, PCB_FLAGS(%r4)	/* Restore FPU regs if needed */
116	andi.	%r9, %r29, 1
117	beq	.L2
118	mr	%r3, %r4
119	bl	enable_fpu
120#endif
121
122	/* thread to restore is in r3 */
123.L2:
124	li      %r15,TDS_RUNNING
125	stw     %r15,TD_STATE(%r3)      /* Set KSE state */
126	lwz	%r3, TD_PCB(%r3)
127	lmw	%r12,PCB_CONTEXT(%r3)	/* Load the non-volatile GP regs */
128	mr	%r2,%r12
129	lwz	%r5,PCB_CR(%r3)		/* Load the condition register */
130	mtcr	%r5
131	lwz	%r5,PCB_LR(%r3)		/* Load the link register */
132	mtlr	%r5
133	lwz	%r1,PCB_SP(%r3)		/* Load the stack pointer */
134	blr
135
136/*
137 * savectx(pcb)
138 * Update pcb, saving current processor state
139 */
140ENTRY(savectx)
141	mr	%r12,%r2
142	stmw	%r12,PCB_CONTEXT(%r3)	/* Save the non-volatile GP regs */
143	mfcr	%r4			/* Save the condition register */
144	stw	%r4,PCB_CONTEXT(%r3)
145	blr
146
147/*
148 * fork_trampoline()
149 * Set up the return from cpu_fork()
150 */
151ENTRY(fork_trampoline)
152	lwz	%r3,CF_FUNC(%r1)
153	lwz	%r4,CF_ARG0(%r1)
154	lwz	%r5,CF_ARG1(%r1)
155	bl	fork_exit
156	addi	%r1,%r1,4
157	b	trapexit
158