[apple/xnu.git] / osfmk / i386 / cswitch.s

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990 Carnegie Mellon University
 * All Rights Reserved.
 * 
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 * 
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 * 
 * any improvements or extensions that they make and grant Carnegie Mellon
 * the rights to redistribute these changes.
 */
/*
 */

#include <platforms.h>

#include <i386/asm.h>
#include <i386/proc_reg.h>
#include <assym.s>

#ifdef	SYMMETRY
#include <sqt/asm_macros.h>
#endif

#if	AT386
#include <i386/mp.h>
#endif	/* AT386 */

#define	CX(addr, reg)	addr(,reg,4)

/*
 * Context switch routines for i386.
 */

Entry(Load_context)
	movl	S_ARG0,%ecx			/* get thread */
	movl	TH_KERNEL_STACK(%ecx),%ecx	/* get kernel stack */
	lea	KERNEL_STACK_SIZE-IKS_SIZE-IEL_SIZE(%ecx),%edx
						/* point to stack top */
	movl	%ecx,%gs:CPU_ACTIVE_STACK	/* store stack address */
	movl	%edx,%gs:CPU_KERNEL_STACK	/* store stack top */

	movl	%edx,%esp
	movl	%edx,%ebp

	xorl	%eax,%eax			/* return zero (no old thread) */
	pushl	%eax
	call	EXT(thread_continue)

/*
 *	This really only has to save registers
 *	when there is no explicit continuation.
 */

Entry(Switch_context)
	movl	%gs:CPU_ACTIVE_STACK,%ecx /* get old kernel stack */

	movl	%ebx,KSS_EBX(%ecx)		/* save registers */
	movl	%ebp,KSS_EBP(%ecx)
	movl	%edi,KSS_EDI(%ecx)
	movl	%esi,KSS_ESI(%ecx)
	popl	KSS_EIP(%ecx)			/* save return PC */
	movl	%esp,KSS_ESP(%ecx)		/* save SP */

	movl	0(%esp),%eax			/* return old thread */
	movl	8(%esp),%ebx			/* get new thread */
	movl    %ebx,%gs:CPU_ACTIVE_THREAD                /* new thread is active */
	movl	TH_KERNEL_STACK(%ebx),%ecx	/* get its kernel stack */
	lea	KERNEL_STACK_SIZE-IKS_SIZE-IEL_SIZE(%ecx),%ebx
						/* point to stack top */

	movl	%ecx,%gs:CPU_ACTIVE_STACK	/* set current stack */
	movl	%ebx,%gs:CPU_KERNEL_STACK	/* set stack top */


	movl	$0,%gs:CPU_ACTIVE_KLOADED

	movl	KSS_ESP(%ecx),%esp		/* switch stacks */
	movl	KSS_ESI(%ecx),%esi		/* restore registers */
	movl	KSS_EDI(%ecx),%edi
	movl	KSS_EBP(%ecx),%ebp
	movl	KSS_EBX(%ecx),%ebx
	jmp	*KSS_EIP(%ecx)			/* return old thread */

Entry(Thread_continue)
	pushl	%eax				/* push the thread argument */
	xorl	%ebp,%ebp			/* zero frame pointer */
	call	*%ebx				/* call real continuation */

/*
 * void machine_processor_shutdown(thread_t thread,
 *				   void (*routine)(processor_t),
 *				   processor_t processor)
 *
 * saves the kernel context of the thread,
 * switches to the interrupt stack,
 * continues the thread (with thread_continue),
 * then runs routine on the interrupt stack.
 *
 * Assumes that the thread is a kernel thread (thus
 * has no FPU state)
 */
Entry(machine_processor_shutdown)
	movl	%gs:CPU_ACTIVE_STACK,%ecx /* get old kernel stack */
	movl	%ebx,KSS_EBX(%ecx)		/* save registers */
	movl	%ebp,KSS_EBP(%ecx)
	movl	%edi,KSS_EDI(%ecx)
	movl	%esi,KSS_ESI(%ecx)
	popl	KSS_EIP(%ecx)			/* save return PC */
	movl	%esp,KSS_ESP(%ecx)		/* save SP */

	movl	0(%esp),%eax			/* get old thread */
	movl	%ecx,TH_KERNEL_STACK(%eax)	/* save old stack */
	movl	4(%esp),%ebx			/* get routine to run next */
	movl	8(%esp),%esi			/* get its argument */

	movl	%gs:CPU_INT_STACK_TOP,%esp 	/* switch to interrupt stack */

	pushl	%esi				/* push argument */
	call	*%ebx				/* call routine to run */
	hlt					/* (should never return) */


        .text

	.globl	EXT(locore_end)
LEXT(locore_end)
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
8f6c56a5	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
8f6c56a5 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
8ad349bb	24	* limitations under the License.
8f6c56a5 A	25	*
8f6c56a5 A	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/*
	29	* @OSF_COPYRIGHT@
	30	*/
	31	/*
	32	* Mach Operating System
	33	* Copyright (c) 1991,1990 Carnegie Mellon University
	34	* All Rights Reserved.
	35	*
	36	* Permission to use, copy, modify and distribute this software and its
	37	* documentation is hereby granted, provided that both the copyright
	38	* notice and this permission notice appear in all copies of the
	39	* software, derivative works or modified versions, and any portions
	40	* thereof, and that both notices appear in supporting documentation.
	41	*
	42	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	43	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	44	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	45	*
	46	* Carnegie Mellon requests users of this software to return to
	47	*
	48	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	49	* School of Computer Science
	50	* Carnegie Mellon University
	51	* Pittsburgh PA 15213-3890
	52	*
	53	* any improvements or extensions that they make and grant Carnegie Mellon
	54	* the rights to redistribute these changes.
	55	*/
	56	/*
	57	*/
	58
1c79356b A	59	#include <platforms.h>
	60
	61	#include <i386/asm.h>
	62	#include <i386/proc_reg.h>
	63	#include <assym.s>
	64
1c79356b A	65	#ifdef SYMMETRY
	66	#include <sqt/asm_macros.h>
	67	#endif
	68
	69	#if AT386
55e303ae	70	#include <i386/mp.h>
1c79356b A	71	#endif /* AT386 */
	72
	73	#define CX(addr, reg) addr(,reg,4)
	74
1c79356b A	75	/*
	76	* Context switch routines for i386.
	77	*/
	78
	79	Entry(Load_context)
	80	movl S_ARG0,%ecx /* get thread */
	81	movl TH_KERNEL_STACK(%ecx),%ecx /* get kernel stack */
	82	lea KERNEL_STACK_SIZE-IKS_SIZE-IEL_SIZE(%ecx),%edx
	83	/* point to stack top */
91447636 A	84	movl %ecx,%gs:CPU_ACTIVE_STACK /* store stack address */
	85	movl %edx,%gs:CPU_KERNEL_STACK /* store stack top */
	86
	87	movl %edx,%esp
	88	movl %edx,%ebp
1c79356b	89
1c79356b	90	xorl %eax,%eax /* return zero (no old thread) */
91447636 A	91	pushl %eax
91447636 A	92	call EXT(thread_continue)
1c79356b A	93
1c79356b A	94	/*
21362eb3	95	* This really only has to save registers
1c79356b A	96	* when there is no explicit continuation.
	97	*/
	98
	99	Entry(Switch_context)
21362eb3	100	movl %gs:CPU_ACTIVE_STACK,%ecx /* get old kernel stack */
1c79356b A	101
	102	movl %ebx,KSS_EBX(%ecx) /* save registers */
	103	movl %ebp,KSS_EBP(%ecx)
	104	movl %edi,KSS_EDI(%ecx)
	105	movl %esi,KSS_ESI(%ecx)
21362eb3	106	popl KSS_EIP(%ecx) /* save return PC */
1c79356b	107	movl %esp,KSS_ESP(%ecx) /* save SP */
21362eb3	108
55e303ae	109	movl 0(%esp),%eax /* return old thread */
91447636	110	movl 8(%esp),%ebx /* get new thread */
21362eb3	111	movl %ebx,%gs:CPU_ACTIVE_THREAD /* new thread is active */
91447636	112	movl TH_KERNEL_STACK(%ebx),%ecx /* get its kernel stack */
1c79356b A	113	lea KERNEL_STACK_SIZE-IKS_SIZE-IEL_SIZE(%ecx),%ebx
	114	/* point to stack top */
	115
91447636 A	116	movl %ecx,%gs:CPU_ACTIVE_STACK /* set current stack */
91447636 A	117	movl %ebx,%gs:CPU_KERNEL_STACK /* set stack top */
1c79356b	118
21362eb3 A	119
	120	movl $0,%gs:CPU_ACTIVE_KLOADED
	121
1c79356b A	122	movl KSS_ESP(%ecx),%esp /* switch stacks */
	123	movl KSS_ESI(%ecx),%esi /* restore registers */
	124	movl KSS_EDI(%ecx),%edi
	125	movl KSS_EBP(%ecx),%ebp
	126	movl KSS_EBX(%ecx),%ebx
	127	jmp KSS_EIP(%ecx) / return old thread */
	128
	129	Entry(Thread_continue)
	130	pushl %eax /* push the thread argument */
	131	xorl %ebp,%ebp /* zero frame pointer */
	132	call %ebx / call real continuation */
	133
1c79356b	134	/*
21362eb3 A	135	* void machine_processor_shutdown(thread_t thread,
	136	* void (*routine)(processor_t),
	137	* processor_t processor)
1c79356b A	138	*
	139	* saves the kernel context of the thread,
	140	* switches to the interrupt stack,
	141	* continues the thread (with thread_continue),
	142	* then runs routine on the interrupt stack.
	143	*
21362eb3 A	144	* Assumes that the thread is a kernel thread (thus
21362eb3 A	145	* has no FPU state)
1c79356b	146	*/
21362eb3	147	Entry(machine_processor_shutdown)
91447636	148	movl %gs:CPU_ACTIVE_STACK,%ecx /* get old kernel stack */
1c79356b A	149	movl %ebx,KSS_EBX(%ecx) /* save registers */
	150	movl %ebp,KSS_EBP(%ecx)
	151	movl %edi,KSS_EDI(%ecx)
	152	movl %esi,KSS_ESI(%ecx)
	153	popl KSS_EIP(%ecx) /* save return PC */
	154	movl %esp,KSS_ESP(%ecx) /* save SP */
	155
	156	movl 0(%esp),%eax /* get old thread */
1c79356b A	157	movl %ecx,TH_KERNEL_STACK(%eax) /* save old stack */
	158	movl 4(%esp),%ebx /* get routine to run next */
	159	movl 8(%esp),%esi /* get its argument */
	160
91447636	161	movl %gs:CPU_INT_STACK_TOP,%esp /* switch to interrupt stack */
1c79356b A	162
	163	pushl %esi /* push argument */
	164	call %ebx / call routine to run */
	165	hlt /* (should never return) */
21362eb3 A	166
	167
	168	.text
	169
	170	.globl EXT(locore_end)
	171	LEXT(locore_end)
	172