diff options
Diffstat (limited to 'src/soc/marvell/armada38x/monotonic_timer.c')
-rw-r--r-- | src/soc/marvell/armada38x/monotonic_timer.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/src/soc/marvell/armada38x/monotonic_timer.c b/src/soc/marvell/armada38x/monotonic_timer.c new file mode 100644 index 0000000000..b314f1185e --- /dev/null +++ b/src/soc/marvell/armada38x/monotonic_timer.c @@ -0,0 +1,58 @@ +/* + * This file is part of the coreboot project. + * + * Copyright 2015 Google Inc. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * 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. + */ + +#include <arch/io.h> +#include <timer.h> +#include <delay.h> + +#define TIMER_CTRL_REG 0xf1020300 +#define TIMER_RELOAD_REG 0xf1020310 +#define TIMER_REG 0xf1020314 +#define TIMER_RELOAD_VALUE 0xffffffff + +#define MHZ_NUM 25 + +void init_timer(void) +{ + unsigned int reg; + + /* Set the reload timer */ + write32((void *)TIMER_RELOAD_REG, TIMER_RELOAD_VALUE); + /* Set the initial value to TIMER_RELOAD_VALUE - 1 + * (instead of TIMER_RELOAD_VALUE) to avoid 'fake' + * overflow being detected in timer_monotonic_get + * if it's called close enough with 'this' function */ + write32((void *)TIMER_REG, TIMER_RELOAD_VALUE - 1); + reg = read32((const void *)TIMER_CTRL_REG); + /* Let it start counting */ + reg |= 0x3; + write32((void *)TIMER_CTRL_REG, reg); +} + +void timer_monotonic_get(struct mono_time *mt) +{ + static uint64_t total_ticks = 0; + uint64_t overflow = 0; + uint32_t current_ticks = + TIMER_RELOAD_VALUE - read32((const void *)TIMER_REG); + + /* Assuming at most one overflow happened since last call */ + if (current_ticks <= total_ticks) + overflow = 1ULL << 32; + + total_ticks = (((total_ticks + overflow) >> 32) << 32) + current_ticks; + mono_time_set_usecs(mt, total_ticks / MHZ_NUM); +} + |