1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * Access to the shared data page by the vDSO & syscall map
5 * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp.
8 #include <asm/processor.h>
9 #include <asm/ppc_asm.h>
10 #include <asm/asm-offsets.h>
11 #include <asm/unistd.h>
15 .global __kernel_datapage_offset;
16 __kernel_datapage_offset:
19 V_FUNCTION_BEGIN(__get_datapage)
21 /* We don't want that exposed or overridable as we want other objects
22 * to be able to bl directly to here
24 .protected __get_datapage
25 .hidden __get_datapage
30 bcl 20,31,data_page_branch
34 addi r3, r3, __kernel_datapage_offset-data_page_branch
40 V_FUNCTION_END(__get_datapage)
43 * void *__kernel_get_syscall_map(unsigned int *syscall_count) ;
45 * returns a pointer to the syscall map. the map is agnostic to the
46 * size of "long", unlike kernel bitops, it stores bits from top to
47 * bottom so that memory actually contains a linear bitmap
48 * check for syscall N by testing bit (0x80000000 >> (N & 0x1f)) of
49 * 32 bits int at N >> 5.
51 V_FUNCTION_BEGIN(__kernel_get_syscall_map)
56 bl __get_datapage@local
58 addi r3,r3,CFG_SYSCALL_MAP32
66 V_FUNCTION_END(__kernel_get_syscall_map)
69 * void unsigned long long __kernel_get_tbfreq(void);
71 * returns the timebase frequency in HZ
73 V_FUNCTION_BEGIN(__kernel_get_tbfreq)
77 bl __get_datapage@local
78 lwz r4,(CFG_TB_TICKS_PER_SEC + 4)(r3)
79 lwz r3,CFG_TB_TICKS_PER_SEC(r3)
84 V_FUNCTION_END(__kernel_get_tbfreq)