[apple/xnu.git] / osfmk / i386 / commpage / commpage_mach_absolute_time.s

/*
 * Copyright (c) 2003-2006 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@
 */

#include <sys/appleapiopts.h>
#include <machine/cpu_capabilities.h>
#include <machine/commpage.h>
#include <i386/asm.h>

#include <assym.s>

        .text
        .align  2, 0x90

Lmach_absolute_time:
	int	$0x3
	ret

	COMMPAGE_DESCRIPTOR(mach_absolute_time,_COMM_PAGE_ABSOLUTE_TIME,0,0)

/* Nanotime is being moved out of the way of bcopy in the commpage.
 * First we put it in both places, old and new.  Then, when all the build
 * trains have rebuilt libSystem, we can remove the deprecated instance.
 */
 
/* return nanotime in %edx:%eax */
Lold_nanotime:
Lnanotime:
	push	%ebp
	mov	%esp,%ebp
	push	%esi
	push	%edi
	push	%ebx

0:
	mov	_COMM_PAGE_NT_TSC_BASE,%esi
	mov	_COMM_PAGE_NT_TSC_BASE+4,%edi

	rdtsc
	sub	%esi,%eax
	sbb	%edi,%edx

	mov	_COMM_PAGE_NT_SCALE,%ecx

	mov	%edx,%ebx
	mull	%ecx
	mov	%ebx,%eax
	mov	%edx,%ebx
	mull	%ecx
	add	%ebx,%eax
	adc	$0,%edx

	add	_COMM_PAGE_NT_NS_BASE,%eax
	adc	_COMM_PAGE_NT_NS_BASE+4,%edx

	cmp	_COMM_PAGE_NT_TSC_BASE,%esi
	jne	0b
	cmp	_COMM_PAGE_NT_TSC_BASE+4,%edi
	jne	0b

	pop	%ebx
	pop	%edi
	pop	%esi
	pop	%ebp
	ret

	COMMPAGE_DESCRIPTOR(nanotime,_COMM_PAGE_NANOTIME,0,0)
	COMMPAGE_DESCRIPTOR(old_nanotime,_COMM_PAGE_OLD_NANOTIME,0,0)


/* The 64-bit version.  We return the 64-bit nanotime in %rax,
 * and by convention we must preserve %r9, %r10, and %r11.
 */
	.text
	.align	2
	.code64
Lold_nanotime_64:
Lnanotime_64:				// NB: must preserve r9, r10, and r11
	pushq	%rbp			// set up a frame for backtraces
	movq	%rsp,%rbp
	movq	$_COMM_PAGE_32_TO_64(_COMM_PAGE_NT_TSC_BASE),%rsi
1:
	movq	_NT_TSC_BASE(%rsi),%r8	// r8  := base_tsc
	rdtsc				// edx:eax := tsc
	shlq	$32,%rdx		// rax := ((edx << 32) | eax), ie 64-bit tsc
	orq	%rdx,%rax
	subq	%r8, %rax		// rax := (tsc - base_tsc)
	movl	_NT_SCALE(%rsi),%ecx
	mulq	%rcx			// rdx:rax := (tsc - base_tsc) * scale
	shrdq	$32,%rdx,%rax		// _COMM_PAGE_NT_SHIFT is always 32
	addq	_NT_NS_BASE(%rsi),%rax	// (((tsc - base_tsc) * scale) >> 32) + ns_base
	
	cmpq	_NT_TSC_BASE(%rsi),%r8	// did the data change during computation?
	jne	1b
	popq	%rbp
	ret

	COMMPAGE_DESCRIPTOR(nanotime_64,_COMM_PAGE_NANOTIME,0,0)
	COMMPAGE_DESCRIPTOR(old_nanotime_64,_COMM_PAGE_OLD_NANOTIME,0,0)
Commit	Line	Data
de355530	1	/*
89b3af67	2	* Copyright (c) 2003-2006 Apple Computer, Inc. All rights reserved.
de355530	3	*
8f6c56a5	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
de355530	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@
de355530	27	*/
de355530	28
55e303ae A	29	#include <sys/appleapiopts.h>
	30	#include <machine/cpu_capabilities.h>
	31	#include <machine/commpage.h>
91447636 A	32	#include <i386/asm.h>
	33
	34	#include <assym.s>
55e303ae A	35
	36	.text
	37	.align 2, 0x90
	38
	39	Lmach_absolute_time:
	40	int $0x3
	41	ret
	42
89b3af67	43	COMMPAGE_DESCRIPTOR(mach_absolute_time,_COMM_PAGE_ABSOLUTE_TIME,0,0)
91447636	44
89b3af67 A	45	/* Nanotime is being moved out of the way of bcopy in the commpage.
	46	* First we put it in both places, old and new. Then, when all the build
	47	* trains have rebuilt libSystem, we can remove the deprecated instance.
	48	*/
	49
	50	/* return nanotime in %edx:%eax */
	51	Lold_nanotime:
8f6c56a5	52	Lnanotime:
89b3af67 A	53	push %ebp
	54	mov %esp,%ebp
	55	push %esi
	56	push %edi
	57	push %ebx
	58
	59	0:
	60	mov _COMM_PAGE_NT_TSC_BASE,%esi
	61	mov _COMM_PAGE_NT_TSC_BASE+4,%edi
	62
	63	rdtsc
	64	sub %esi,%eax
	65	sbb %edi,%edx
	66
	67	mov _COMM_PAGE_NT_SCALE,%ecx
	68
	69	mov %edx,%ebx
	70	mull %ecx
	71	mov %ebx,%eax
	72	mov %edx,%ebx
	73	mull %ecx
	74	add %ebx,%eax
	75	adc $0,%edx
	76
	77	add _COMM_PAGE_NT_NS_BASE,%eax
	78	adc _COMM_PAGE_NT_NS_BASE+4,%edx
	79
	80	cmp _COMM_PAGE_NT_TSC_BASE,%esi
	81	jne 0b
	82	cmp _COMM_PAGE_NT_TSC_BASE+4,%edi
	83	jne 0b
	84
	85	pop %ebx
	86	pop %edi
	87	pop %esi
	88	pop %ebp
	89	ret
c0fea474	90
89b3af67 A	91	COMMPAGE_DESCRIPTOR(nanotime,_COMM_PAGE_NANOTIME,0,0)
89b3af67 A	92	COMMPAGE_DESCRIPTOR(old_nanotime,_COMM_PAGE_OLD_NANOTIME,0,0)
5d5c5d0d	93
89b3af67 A	94
	95	/* The 64-bit version. We return the 64-bit nanotime in %rax,
	96	* and by convention we must preserve %r9, %r10, and %r11.
	97	*/
	98	.text
	99	.align 2
	100	.code64
	101	Lold_nanotime_64:
	102	Lnanotime_64: // NB: must preserve r9, r10, and r11
	103	pushq %rbp // set up a frame for backtraces
	104	movq %rsp,%rbp
	105	movq $_COMM_PAGE_32_TO_64(_COMM_PAGE_NT_TSC_BASE),%rsi
91447636	106	1:
89b3af67 A	107	movq _NT_TSC_BASE(%rsi),%r8 // r8 := base_tsc
	108	rdtsc // edx:eax := tsc
	109	shlq $32,%rdx // rax := ((edx << 32) \| eax), ie 64-bit tsc
	110	orq %rdx,%rax
	111	subq %r8, %rax // rax := (tsc - base_tsc)
	112	movl _NT_SCALE(%rsi),%ecx
	113	mulq %rcx // rdx:rax := (tsc - base_tsc) * scale
	114	shrdq $32,%rdx,%rax // _COMM_PAGE_NT_SHIFT is always 32
	115	addq _NT_NS_BASE(%rsi),%rax // (((tsc - base_tsc) * scale) >> 32) + ns_base
	116
	117	cmpq _NT_TSC_BASE(%rsi),%r8 // did the data change during computation?
91447636	118	jne 1b
89b3af67	119	popq %rbp
91447636 A	120	ret
91447636 A	121
89b3af67 A	122	COMMPAGE_DESCRIPTOR(nanotime_64,_COMM_PAGE_NANOTIME,0,0)
89b3af67 A	123	COMMPAGE_DESCRIPTOR(old_nanotime_64,_COMM_PAGE_OLD_NANOTIME,0,0)