| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* | 
 | 2 |  * Access to the shared data page by the vDSO & syscall map | 
 | 3 |  * | 
 | 4 |  * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp. | 
 | 5 |  * | 
 | 6 |  * This program is free software; you can redistribute it and/or | 
 | 7 |  * modify it under the terms of the GNU General Public License | 
 | 8 |  * as published by the Free Software Foundation; either version | 
 | 9 |  * 2 of the License, or (at your option) any later version. | 
 | 10 |  */ | 
 | 11 |  | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <asm/processor.h> | 
 | 13 | #include <asm/ppc_asm.h> | 
| Sam Ravnborg | 0013a85 | 2005-09-09 20:57:26 +0200 | [diff] [blame] | 14 | #include <asm/asm-offsets.h> | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <asm/unistd.h> | 
 | 16 | #include <asm/vdso.h> | 
 | 17 |  | 
 | 18 | 	.text | 
 | 19 | V_FUNCTION_BEGIN(__get_datapage) | 
 | 20 |   .cfi_startproc | 
 | 21 | 	/* We don't want that exposed or overridable as we want other objects | 
 | 22 | 	 * to be able to bl directly to here | 
 | 23 | 	 */ | 
 | 24 | 	.protected __get_datapage | 
 | 25 | 	.hidden __get_datapage | 
 | 26 |  | 
 | 27 | 	mflr	r0 | 
 | 28 |   .cfi_register lr,r0 | 
 | 29 |  | 
 | 30 | 	bcl	20,31,1f | 
 | 31 | 	.global	__kernel_datapage_offset; | 
 | 32 | __kernel_datapage_offset: | 
 | 33 | 	.long	0 | 
 | 34 | 1: | 
 | 35 | 	mflr	r3 | 
 | 36 | 	mtlr	r0 | 
 | 37 | 	lwz	r0,0(r3) | 
 | 38 | 	add	r3,r0,r3 | 
 | 39 | 	blr | 
 | 40 |   .cfi_endproc | 
 | 41 | V_FUNCTION_END(__get_datapage) | 
 | 42 |  | 
 | 43 | /* | 
 | 44 |  * void *__kernel_get_syscall_map(unsigned int *syscall_count) ; | 
 | 45 |  * | 
 | 46 |  * returns a pointer to the syscall map. the map is agnostic to the | 
 | 47 |  * size of "long", unlike kernel bitops, it stores bits from top to | 
 | 48 |  * bottom so that memory actually contains a linear bitmap | 
 | 49 |  * check for syscall N by testing bit (0x80000000 >> (N & 0x1f)) of | 
 | 50 |  * 32 bits int at N >> 5. | 
 | 51 |  */ | 
 | 52 | V_FUNCTION_BEGIN(__kernel_get_syscall_map) | 
 | 53 |   .cfi_startproc | 
 | 54 | 	mflr	r12 | 
 | 55 |   .cfi_register lr,r12 | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 56 | 	mr	r4,r3 | 
 | 57 | 	bl	__get_datapage@local | 
 | 58 | 	mtlr	r12 | 
 | 59 | 	addi	r3,r3,CFG_SYSCALL_MAP32 | 
 | 60 | 	cmpli	cr0,r4,0 | 
 | 61 | 	beqlr | 
 | 62 | 	li	r0,__NR_syscalls | 
 | 63 | 	stw	r0,0(r4) | 
| Benjamin Herrenschmidt | 5d66da3 | 2005-11-16 13:54:32 +1100 | [diff] [blame] | 64 | 	crclr	cr0*4+so | 
| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | 	blr | 
 | 66 |   .cfi_endproc | 
 | 67 | V_FUNCTION_END(__kernel_get_syscall_map) | 
| Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 68 |  | 
 | 69 | /* | 
 | 70 |  * void unsigned long long  __kernel_get_tbfreq(void); | 
 | 71 |  * | 
 | 72 |  * returns the timebase frequency in HZ | 
 | 73 |  */ | 
 | 74 | V_FUNCTION_BEGIN(__kernel_get_tbfreq) | 
 | 75 |   .cfi_startproc | 
 | 76 | 	mflr	r12 | 
 | 77 |   .cfi_register lr,r12 | 
 | 78 | 	bl	__get_datapage@local | 
| Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 79 | 	lwz	r4,(CFG_TB_TICKS_PER_SEC + 4)(r3) | 
| Benjamin Herrenschmidt | 0c37ec2 | 2005-11-14 14:55:58 +1100 | [diff] [blame] | 80 | 	lwz	r3,CFG_TB_TICKS_PER_SEC(r3) | 
| Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 81 | 	mtlr	r12 | 
| Benjamin Herrenschmidt | 5d66da3 | 2005-11-16 13:54:32 +1100 | [diff] [blame] | 82 | 	crclr	cr0*4+so | 
| Benjamin Herrenschmidt | 0c37ec2 | 2005-11-14 14:55:58 +1100 | [diff] [blame] | 83 | 	blr | 
| Benjamin Herrenschmidt | a7f290d | 2005-11-11 21:15:21 +1100 | [diff] [blame] | 84 |   .cfi_endproc | 
 | 85 | V_FUNCTION_END(__kernel_get_tbfreq) |