| /* |
| * Copyright (c) 2021-2022 Arm Limited. All rights reserved. |
| * SPDX-License-Identifier: Apache-2.0 |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| #include "timer_simple_platform.h" |
| |
| #include "log_macros.h" /* Logging macros */ |
| #include "RTE_Components.h" /* For CPU related defintiions */ |
| |
| #include <inttypes.h> |
| |
| static uint64_t cpu_cycle_count = 0; /* 64-bit cpu cycle counter */ |
| extern uint32_t SystemCoreClock; /* Expected to come from the cmsis-device lib */ |
| |
| /** |
| * @brief Gets the system tick triggered cycle counter for the CPU. |
| * @return 64-bit counter value. |
| **/ |
| static uint64_t Get_SysTick_Cycle_Count(void); |
| |
| /** |
| * SysTick initialisation |
| */ |
| static int Init_SysTick(void); |
| |
| |
| base_time_counter get_time_counter(void) |
| { |
| base_time_counter t = { |
| .counter_systick = Get_SysTick_Cycle_Count() |
| }; |
| debug("counter_systick: %" PRIu64 "\n", t.counter_systick); |
| return t; |
| } |
| |
| void timer_reset(void) |
| { |
| if (0 != Init_SysTick()) { |
| printf_err("Failed to initialise system tick config\n"); |
| } |
| debug("system tick config ready\n"); |
| } |
| |
| uint64_t get_cycle_count_diff(base_time_counter *start, |
| base_time_counter *end) |
| { |
| if (start->counter_systick > end->counter_systick) { |
| warn("start > end; counter might have overflown\n"); |
| } |
| return end->counter_systick - start->counter_systick; |
| } |
| |
| void start_cycle_counter(void) |
| { |
| /* Add any custom requirement for this platform here */ |
| } |
| |
| void stop_cycle_counter(void) |
| { |
| /* Add any custom requirement for this platform here */ |
| } |
| |
| |
| void SysTick_Handler(void) |
| { |
| /* Increment the cycle counter based on load value. */ |
| cpu_cycle_count += SysTick->LOAD + 1; |
| } |
| |
| /** |
| * Gets the current SysTick derived counter value |
| */ |
| static uint64_t Get_SysTick_Cycle_Count(void) |
| { |
| uint32_t systick_val; |
| |
| NVIC_DisableIRQ(SysTick_IRQn); |
| systick_val = SysTick->VAL & SysTick_VAL_CURRENT_Msk; |
| NVIC_EnableIRQ(SysTick_IRQn); |
| |
| return cpu_cycle_count + (SysTick->LOAD - systick_val); |
| } |
| |
| /** |
| * SysTick initialisation |
| */ |
| static int Init_SysTick(void) |
| { |
| const uint32_t ticks_10ms = SystemCoreClock/100 + 1; |
| int err = 0; |
| |
| /* Reset CPU cycle count value. */ |
| cpu_cycle_count = 0; |
| |
| /* Changing configuration for sys tick => guard from being |
| * interrupted. */ |
| NVIC_DisableIRQ(SysTick_IRQn); |
| |
| /* SysTick init - this will enable interrupt too. */ |
| err = SysTick_Config(ticks_10ms); |
| |
| /* Enable interrupt again. */ |
| NVIC_EnableIRQ(SysTick_IRQn); |
| |
| /* Wait for SysTick to kick off */ |
| while (!err && !SysTick->VAL) { |
| __NOP(); |
| } |
| |
| return err; |
| } |