2N/A/* rtc_get_time_ms.c - get_time_ms implementation using platform RTC.
2N/A * The generic implementation of these functions can be used for architectures
2N/A * or platforms that do not have a more specialized implementation. */
2N/A/*
2N/A * GRUB -- GRand Unified Bootloader
2N/A * Copyright (C) 2008 Free Software Foundation, Inc.
2N/A *
2N/A * GRUB is free software: you can redistribute it and/or modify
2N/A * it under the terms of the GNU General Public License as published by
2N/A * the Free Software Foundation, either version 3 of the License, or
2N/A * (at your option) any later version.
2N/A *
2N/A * GRUB is distributed in the hope that it will be useful,
2N/A * but WITHOUT ANY WARRANTY; without even the implied warranty of
2N/A * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
2N/A * GNU General Public License for more details.
2N/A *
2N/A * You should have received a copy of the GNU General Public License
2N/A * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
2N/A */
2N/A
2N/A#include <grub/time.h>
2N/A#include <grub/misc.h>
2N/A
2N/A/* Calculate the time in milliseconds since the epoch based on the RTC. */
2N/Agrub_uint64_t
2N/Agrub_rtc_get_time_ms (void)
2N/A{
2N/A /* By dimensional analysis:
2N/A
2N/A 1000 ms N rtc ticks 1 s
2N/A ------- * ----------- * ----------- = 1000*N/T ms
2N/A 1 s 1 T rtc ticks
2N/A */
2N/A grub_uint64_t ticks_ms_per_sec = ((grub_uint64_t) 1000) * grub_get_rtc ();
2N/A return grub_divmod64 (ticks_ms_per_sec, GRUB_TICKS_PER_SECOND, 0);
2N/A}