| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 2 | /* |
| 3 | * Access to the shared data page by the vDSO & syscall map |
| 4 | * |
| 5 | * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp. |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 6 | */ |
| 7 | |
| 8 | #include <asm/processor.h> |
| 9 | #include <asm/ppc_asm.h> |
| 10 | #include <asm/asm-offsets.h> |
| 11 | #include <asm/unistd.h> |
| 12 | #include <asm/vdso.h> |
| 13 | |
| 14 | .text |
| 15 | .global __kernel_datapage_offset; |
| 16 | __kernel_datapage_offset: |
| 17 | .long 0 |
| 18 | |
| 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,data_page_branch |
| 31 | data_page_branch: |
| 32 | mflr r3 |
| 33 | mtlr r0 |
| 34 | addi r3, r3, __kernel_datapage_offset-data_page_branch |
| 35 | lwz r0,0(r3) |
| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 36 | .cfi_restore lr |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 37 | add r3,r0,r3 |
| 38 | blr |
| 39 | .cfi_endproc |
| 40 | V_FUNCTION_END(__get_datapage) |
| 41 | |
| 42 | /* |
| 43 | * void *__kernel_get_syscall_map(unsigned int *syscall_count) ; |
| 44 | * |
| 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. |
| 50 | */ |
| 51 | V_FUNCTION_BEGIN(__kernel_get_syscall_map) |
| 52 | .cfi_startproc |
| 53 | mflr r12 |
| 54 | .cfi_register lr,r12 |
| 55 | mr r4,r3 |
| 56 | bl __get_datapage@local |
| 57 | mtlr r12 |
| 58 | addi r3,r3,CFG_SYSCALL_MAP32 |
| 59 | cmpli cr0,r4,0 |
| 60 | beqlr |
| 61 | li r0,NR_syscalls |
| 62 | stw r0,0(r4) |
| 63 | crclr cr0*4+so |
| 64 | blr |
| 65 | .cfi_endproc |
| 66 | V_FUNCTION_END(__kernel_get_syscall_map) |
| 67 | |
| 68 | /* |
| 69 | * void unsigned long long __kernel_get_tbfreq(void); |
| 70 | * |
| 71 | * returns the timebase frequency in HZ |
| 72 | */ |
| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 73 | #ifndef CONFIG_PPC_BOOK3S_601 |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 74 | V_FUNCTION_BEGIN(__kernel_get_tbfreq) |
| 75 | .cfi_startproc |
| 76 | mflr r12 |
| 77 | .cfi_register lr,r12 |
| 78 | bl __get_datapage@local |
| 79 | lwz r4,(CFG_TB_TICKS_PER_SEC + 4)(r3) |
| 80 | lwz r3,CFG_TB_TICKS_PER_SEC(r3) |
| 81 | mtlr r12 |
| 82 | crclr cr0*4+so |
| 83 | blr |
| 84 | .cfi_endproc |
| 85 | V_FUNCTION_END(__kernel_get_tbfreq) |
| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 86 | #endif |