blob: 1bca06ee98c6bea8298998f2eef0530179c5dc0e [file] [log] [blame]
* Copyright (c) 2017 Intel Corporation
* SPDX-License-Identifier: Apache-2.0
#include <zephyr/kernel.h>
#include <zephyr/arch/cpu.h>
#include <zephyr/device.h>
#include <zephyr/drivers/timer/system_timer.h>
#include <altera_common.h>
#include "altera_avalon_timer_regs.h"
#include "altera_avalon_timer.h"
/* The old driver "now" API would return a full uptime value. The new
* one only requires the driver to track ticks since the last announce
* call. Implement the new call in terms of the old one on legacy
* drivers by keeping (yet another) uptime value locally.
static uint32_t driver_uptime;
static uint32_t accumulated_cycle_count;
static int32_t _sys_idle_elapsed_ticks = 1;
#if defined(CONFIG_TEST)
const int32_t z_sys_timer_irq_for_test = TIMER_0_IRQ;
static void wrapped_announce(int32_t ticks)
driver_uptime += ticks;
static void timer_irq_handler(const void *unused)
accumulated_cycle_count += k_ticks_to_cyc_floor32(1);
/* Clear the interrupt */
alt_handle_irq((void *)TIMER_0_BASE, TIMER_0_IRQ);
uint32_t sys_clock_cycle_get_32(void)
/* Per the Altera Embedded IP Peripherals guide, you cannot
* use a timer instance for both the system clock and timestamps
* at the same time.
* Having this function return accumulated_cycle_count + get_snapshot()
* does not work reliably. It's possible for the current countdown
* to reset to the next interval before the timer interrupt is
* delivered (and accumulated cycle count gets updated). The result
* is an unlucky call to this function will appear to jump backward
* in time.
* To properly obtain timestamps, the CPU must be configured with
* a second timer peripheral instance that is configured to
* count down from some large initial 64-bit value. This
* is currently unimplemented.
return accumulated_cycle_count;
uint32_t sys_clock_elapsed(void)
return 0;
static int sys_clock_driver_init(const struct device *dev)
k_ticks_to_cyc_floor32(1) & 0xFFFF);
(k_ticks_to_cyc_floor32(1) >> 16) & 0xFFFF);
IRQ_CONNECT(TIMER_0_IRQ, 0, timer_irq_handler, NULL, 0);
alt_avalon_timer_sc_init((void *)TIMER_0_BASE, 0,
TIMER_0_IRQ, k_ticks_to_cyc_floor32(1));
return 0;
SYS_INIT(sys_clock_driver_init, PRE_KERNEL_2,