diff options
Diffstat (limited to 'arch/arm64/kernel/vdso/gettimeofday.S')
| -rw-r--r-- | arch/arm64/kernel/vdso/gettimeofday.S | 244 |
1 files changed, 0 insertions, 244 deletions
diff --git a/arch/arm64/kernel/vdso/gettimeofday.S b/arch/arm64/kernel/vdso/gettimeofday.S deleted file mode 100644 index f0a6d10b5211..000000000000 --- a/arch/arm64/kernel/vdso/gettimeofday.S +++ /dev/null @@ -1,244 +0,0 @@ -/* - * Userspace implementations of gettimeofday() and friends. - * - * Copyright (C) 2012 ARM Limited - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - * - * Author: Will Deacon <will.deacon@arm.com> - */ - -#include <linux/linkage.h> -#include <asm/asm-offsets.h> -#include <asm/unistd.h> - -#define NSEC_PER_SEC_LO16 0xca00 -#define NSEC_PER_SEC_HI16 0x3b9a - -vdso_data .req x6 -use_syscall .req w7 -seqcnt .req w8 - - .macro seqcnt_acquire -9999: ldr seqcnt, [vdso_data, #VDSO_TB_SEQ_COUNT] - tbnz seqcnt, #0, 9999b - dmb ishld - ldr use_syscall, [vdso_data, #VDSO_USE_SYSCALL] - .endm - - .macro seqcnt_read, cnt - dmb ishld - ldr \cnt, [vdso_data, #VDSO_TB_SEQ_COUNT] - .endm - - .macro seqcnt_check, cnt, fail - cmp \cnt, seqcnt - b.ne \fail - .endm - - .text - -/* int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz); */ -ENTRY(__kernel_gettimeofday) - .cfi_startproc - mov x2, x30 - .cfi_register x30, x2 - - /* Acquire the sequence counter and get the timespec. */ - adr vdso_data, _vdso_data -1: seqcnt_acquire - cbnz use_syscall, 4f - - /* If tv is NULL, skip to the timezone code. */ - cbz x0, 2f - bl __do_get_tspec - seqcnt_check w9, 1b - - /* Convert ns to us. */ - mov x13, #1000 - lsl x13, x13, x12 - udiv x11, x11, x13 - stp x10, x11, [x0, #TVAL_TV_SEC] -2: - /* If tz is NULL, return 0. */ - cbz x1, 3f - ldp w4, w5, [vdso_data, #VDSO_TZ_MINWEST] - stp w4, w5, [x1, #TZ_MINWEST] -3: - mov x0, xzr - ret x2 -4: - /* Syscall fallback. */ - mov x8, #__NR_gettimeofday - svc #0 - ret x2 - .cfi_endproc -ENDPROC(__kernel_gettimeofday) - -/* int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp); */ -ENTRY(__kernel_clock_gettime) - .cfi_startproc - cmp w0, #CLOCK_REALTIME - ccmp w0, #CLOCK_MONOTONIC, #0x4, ne - b.ne 2f - - mov x2, x30 - .cfi_register x30, x2 - - /* Get kernel timespec. */ - adr vdso_data, _vdso_data -1: seqcnt_acquire - cbnz use_syscall, 7f - - bl __do_get_tspec - seqcnt_check w9, 1b - - cmp w0, #CLOCK_MONOTONIC - b.ne 6f - - /* Get wtm timespec. */ - ldp x13, x14, [vdso_data, #VDSO_WTM_CLK_SEC] - - /* Check the sequence counter. */ - seqcnt_read w9 - seqcnt_check w9, 1b - b 4f -2: - cmp w0, #CLOCK_REALTIME_COARSE - ccmp w0, #CLOCK_MONOTONIC_COARSE, #0x4, ne - b.ne 8f - - /* Get coarse timespec. */ - adr vdso_data, _vdso_data -3: seqcnt_acquire - ldp x10, x11, [vdso_data, #VDSO_XTIME_CRS_SEC] - - /* Get wtm timespec. */ - ldp x13, x14, [vdso_data, #VDSO_WTM_CLK_SEC] - - /* Check the sequence counter. */ - seqcnt_read w9 - seqcnt_check w9, 3b - - cmp w0, #CLOCK_MONOTONIC_COARSE - b.ne 6f -4: - /* Add on wtm timespec. */ - add x10, x10, x13 - lsl x14, x14, x12 - add x11, x11, x14 - - /* Normalise the new timespec. */ - mov x15, #NSEC_PER_SEC_LO16 - movk x15, #NSEC_PER_SEC_HI16, lsl #16 - lsl x15, x15, x12 - cmp x11, x15 - b.lt 5f - sub x11, x11, x15 - add x10, x10, #1 -5: - cmp x11, #0 - b.ge 6f - add x11, x11, x15 - sub x10, x10, #1 - -6: /* Store to the user timespec. */ - lsr x11, x11, x12 - stp x10, x11, [x1, #TSPEC_TV_SEC] - mov x0, xzr - ret x2 -7: - mov x30, x2 -8: /* Syscall fallback. */ - mov x8, #__NR_clock_gettime - svc #0 - ret - .cfi_endproc -ENDPROC(__kernel_clock_gettime) - -/* int __kernel_clock_getres(clockid_t clock_id, struct timespec *res); */ -ENTRY(__kernel_clock_getres) - .cfi_startproc - cbz w1, 3f - - cmp w0, #CLOCK_REALTIME - ccmp w0, #CLOCK_MONOTONIC, #0x4, ne - b.ne 1f - - ldr x2, 5f - b 2f -1: - cmp w0, #CLOCK_REALTIME_COARSE - ccmp w0, #CLOCK_MONOTONIC_COARSE, #0x4, ne - b.ne 4f - ldr x2, 6f -2: - stp xzr, x2, [x1] - -3: /* res == NULL. */ - mov w0, wzr - ret - -4: /* Syscall fallback. */ - mov x8, #__NR_clock_getres - svc #0 - ret -5: - .quad CLOCK_REALTIME_RES -6: - .quad CLOCK_COARSE_RES - .cfi_endproc -ENDPROC(__kernel_clock_getres) - -/* - * Read the current time from the architected counter. - * Expects vdso_data to be initialised. - * Clobbers the temporary registers (x9 - x15). - * Returns: - * - w9 = vDSO sequence counter - * - (x10, x11) = (ts->tv_sec, shifted ts->tv_nsec) - * - w12 = cs_shift - */ -ENTRY(__do_get_tspec) - .cfi_startproc - - /* Read from the vDSO data page. */ - ldr x10, [vdso_data, #VDSO_CS_CYCLE_LAST] - ldp x13, x14, [vdso_data, #VDSO_XTIME_CLK_SEC] - ldp w11, w12, [vdso_data, #VDSO_CS_MULT] - seqcnt_read w9 - - /* Read the virtual counter. */ - isb - mrs x15, cntvct_el0 - - /* Calculate cycle delta and convert to ns. */ - sub x10, x15, x10 - /* We can only guarantee 56 bits of precision. */ - movn x15, #0xff00, lsl #48 - and x10, x15, x10 - mul x10, x10, x11 - - /* Use the kernel time to calculate the new timespec. */ - mov x11, #NSEC_PER_SEC_LO16 - movk x11, #NSEC_PER_SEC_HI16, lsl #16 - lsl x11, x11, x12 - add x15, x10, x14 - udiv x14, x15, x11 - add x10, x13, x14 - mul x13, x14, x11 - sub x11, x15, x13 - - ret - .cfi_endproc -ENDPROC(__do_get_tspec) |