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

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_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. 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_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	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
ff6e181a 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. Please obtain a copy of the License at
	10	* http://www.opensource.apple.com/apsl/ and read it before using this
	11	* file.
1c79356b	12	*
ff6e181a A	13	* The Original Code and all software distributed under the License are
ff6e181a A	14	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	15	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	16	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
ff6e181a A	17	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	18	* Please see the License for the specific language governing rights and
	19	* limitations under the License.
1c79356b A	20	*
	21	* @APPLE_LICENSE_HEADER_END@
	22	*/
	23	/*
	24	* @OSF_COPYRIGHT@
	25	*/
	26	/*
	27	* Mach Operating System
	28	* Copyright (c) 1991,1990 Carnegie Mellon University
	29	* All Rights Reserved.
	30	*
	31	* Permission to use, copy, modify and distribute this software and its
	32	* documentation is hereby granted, provided that both the copyright
	33	* notice and this permission notice appear in all copies of the
	34	* software, derivative works or modified versions, and any portions
	35	* thereof, and that both notices appear in supporting documentation.
	36	*
	37	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	38	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	39	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	40	*
	41	* Carnegie Mellon requests users of this software to return to
	42	*
	43	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	44	* School of Computer Science
	45	* Carnegie Mellon University
	46	* Pittsburgh PA 15213-3890
	47	*
	48	* any improvements or extensions that they make and grant Carnegie Mellon
	49	* the rights to redistribute these changes.
	50	*/
	51	/*
	52	*/
	53
1c79356b A	54	#include <platforms.h>
	55
	56	#include <i386/asm.h>
	57	#include <i386/proc_reg.h>
	58	#include <assym.s>
	59
1c79356b A	60	#ifdef SYMMETRY
	61	#include <sqt/asm_macros.h>
	62	#endif
	63
	64	#if AT386
55e303ae	65	#include <i386/mp.h>
1c79356b A	66	#endif /* AT386 */
	67
	68	#define CX(addr, reg) addr(,reg,4)
	69
1c79356b A	70	/*
	71	* Context switch routines for i386.
	72	*/
	73
	74	Entry(Load_context)
	75	movl S_ARG0,%ecx /* get thread */
	76	movl TH_KERNEL_STACK(%ecx),%ecx /* get kernel stack */
	77	lea KERNEL_STACK_SIZE-IKS_SIZE-IEL_SIZE(%ecx),%edx
	78	/* point to stack top */
91447636 A	79	movl %ecx,%gs:CPU_ACTIVE_STACK /* store stack address */
	80	movl %edx,%gs:CPU_KERNEL_STACK /* store stack top */
	81
	82	movl %edx,%esp
	83	movl %edx,%ebp
1c79356b	84
1c79356b	85	xorl %eax,%eax /* return zero (no old thread) */
91447636 A	86	pushl %eax
91447636 A	87	call EXT(thread_continue)
1c79356b A	88
	89	/*
	90	* This really only has to save registers
	91	* when there is no explicit continuation.
	92	*/
	93
	94	Entry(Switch_context)
91447636	95	movl %gs:CPU_ACTIVE_STACK,%ecx /* get old kernel stack */
1c79356b A	96
	97	movl %ebx,KSS_EBX(%ecx) /* save registers */
	98	movl %ebp,KSS_EBP(%ecx)
	99	movl %edi,KSS_EDI(%ecx)
	100	movl %esi,KSS_ESI(%ecx)
	101	popl KSS_EIP(%ecx) /* save return PC */
	102	movl %esp,KSS_ESP(%ecx) /* save SP */
	103
55e303ae	104	movl 0(%esp),%eax /* return old thread */
91447636 A	105	movl 8(%esp),%ebx /* get new thread */
	106	movl %ebx,%gs:CPU_ACTIVE_THREAD /* new thread is active */
	107	movl TH_KERNEL_STACK(%ebx),%ecx /* get its kernel stack */
1c79356b A	108	lea KERNEL_STACK_SIZE-IKS_SIZE-IEL_SIZE(%ecx),%ebx
	109	/* point to stack top */
	110
91447636 A	111	movl %ecx,%gs:CPU_ACTIVE_STACK /* set current stack */
91447636 A	112	movl %ebx,%gs:CPU_KERNEL_STACK /* set stack top */
1c79356b	113
55e303ae	114
91447636	115	movl $0,%gs:CPU_ACTIVE_KLOADED
55e303ae	116
1c79356b A	117	movl KSS_ESP(%ecx),%esp /* switch stacks */
	118	movl KSS_ESI(%ecx),%esi /* restore registers */
	119	movl KSS_EDI(%ecx),%edi
	120	movl KSS_EBP(%ecx),%ebp
	121	movl KSS_EBX(%ecx),%ebx
	122	jmp KSS_EIP(%ecx) / return old thread */
	123
	124	Entry(Thread_continue)
	125	pushl %eax /* push the thread argument */
	126	xorl %ebp,%ebp /* zero frame pointer */
	127	call %ebx / call real continuation */
	128
1c79356b	129	/*
91447636	130	* void machine_processor_shutdown(thread_t thread,
1c79356b A	131	* void (*routine)(processor_t),
	132	* processor_t processor)
	133	*
	134	* saves the kernel context of the thread,
	135	* switches to the interrupt stack,
	136	* continues the thread (with thread_continue),
	137	* then runs routine on the interrupt stack.
	138	*
	139	* Assumes that the thread is a kernel thread (thus
	140	* has no FPU state)
	141	*/
91447636 A	142	Entry(machine_processor_shutdown)
91447636 A	143	movl %gs:CPU_ACTIVE_STACK,%ecx /* get old kernel stack */
1c79356b A	144	movl %ebx,KSS_EBX(%ecx) /* save registers */
	145	movl %ebp,KSS_EBP(%ecx)
	146	movl %edi,KSS_EDI(%ecx)
	147	movl %esi,KSS_ESI(%ecx)
	148	popl KSS_EIP(%ecx) /* save return PC */
	149	movl %esp,KSS_ESP(%ecx) /* save SP */
	150
	151	movl 0(%esp),%eax /* get old thread */
1c79356b A	152	movl %ecx,TH_KERNEL_STACK(%eax) /* save old stack */
	153	movl 4(%esp),%ebx /* get routine to run next */
	154	movl 8(%esp),%esi /* get its argument */
	155
91447636	156	movl %gs:CPU_INT_STACK_TOP,%esp /* switch to interrupt stack */
1c79356b A	157
	158	pushl %esi /* push argument */
	159	call %ebx / call routine to run */
	160	hlt /* (should never return) */
	161
1c79356b A	162
	163	.text
	164
	165	.globl EXT(locore_end)
	166	LEXT(locore_end)
	167