| /* |
| * 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 <delay.h> |
| #include <soc/addressmap.h> |
| #include <timer.h> |
| |
| #define TIMER_GLB_TIM_CTRL_PRESC_MASK 0x0000FF00 |
| #define TIMER_GLB_TIM_CTRL_TIM_EN 0x00000001 |
| #define TIMER_GLB_TIM_CTRL_PRESC 0x0 |
| /* |
| * arm clk is 1GHz, periph_clk=arm_clk/2, tick per usec. |
| * arm clk is set by the bootrom. See util/broadcom/unauth.cfg for details. |
| */ |
| #define PERIPH_CLOCK 500 |
| #define CLOCKS_PER_USEC (PERIPH_CLOCK / \ |
| (((TIMER_GLB_TIM_CTRL_PRESC & TIMER_GLB_TIM_CTRL_PRESC_MASK) >> 8) + 1)) |
| |
| struct cygnus_timer { |
| u32 gtim_glob_low; |
| u32 gtim_glob_hi; |
| u32 gtim_glob_ctrl; |
| }; |
| |
| static struct cygnus_timer * const timer_ptr = |
| (void *)IPROC_PERIPH_GLB_TIM_REG_BASE; |
| |
| static inline uint64_t timer_raw_value(void) |
| { |
| uint64_t cur_tick; |
| uint32_t count_h; |
| uint32_t count_l; |
| |
| do { |
| count_h = read32(&timer_ptr->gtim_glob_hi); |
| count_l = read32(&timer_ptr->gtim_glob_low); |
| cur_tick = read32(&timer_ptr->gtim_glob_hi); |
| } while (cur_tick != count_h); |
| |
| return (cur_tick << 32) + count_l; |
| } |
| |
| void timer_monotonic_get(struct mono_time *mt) |
| { |
| mono_time_set_usecs(mt, timer_raw_value() / CLOCKS_PER_USEC); |
| } |
| |
| void init_timer(void) |
| { |
| write32(&timer_ptr->gtim_glob_ctrl, TIMER_GLB_TIM_CTRL_PRESC); |
| write32(&timer_ptr->gtim_glob_low, 0); |
| write32(&timer_ptr->gtim_glob_hi, 0); |
| write32(&timer_ptr->gtim_glob_ctrl, TIMER_GLB_TIM_CTRL_TIM_EN); |
| } |