Daniel Vizcaya / Mbed OS 04_RTOS_Embebidos

Entrega 3er corte - sistemas embebidos

mbed-os/rtos/Kernel.cpp@0:6ad07c9019fd, 2018-05-30 (annotated)

Committer:
Bethory
Date:
Wed May 30 00:01:50 2018 +0000
Revision:
0:6ad07c9019fd
Codigo de tales para todos los pasculaes

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Bethory 0:6ad07c9019fd 1 /* mbed Microcontroller Library
Bethory 0:6ad07c9019fd 2 * Copyright (c) 2017 ARM Limited
Bethory 0:6ad07c9019fd 3 *
Bethory 0:6ad07c9019fd 4 * Permission is hereby granted, free of charge, to any person obtaining a copy
Bethory 0:6ad07c9019fd 5 * of this software and associated documentation files (the "Software"), to deal
Bethory 0:6ad07c9019fd 6 * in the Software without restriction, including without limitation the rights
Bethory 0:6ad07c9019fd 7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
Bethory 0:6ad07c9019fd 8 * copies of the Software, and to permit persons to whom the Software is
Bethory 0:6ad07c9019fd 9 * furnished to do so, subject to the following conditions:
Bethory 0:6ad07c9019fd 10 *
Bethory 0:6ad07c9019fd 11 * The above copyright notice and this permission notice shall be included in
Bethory 0:6ad07c9019fd 12 * all copies or substantial portions of the Software.
Bethory 0:6ad07c9019fd 13 *
Bethory 0:6ad07c9019fd 14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
Bethory 0:6ad07c9019fd 15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
Bethory 0:6ad07c9019fd 16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
Bethory 0:6ad07c9019fd 17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
Bethory 0:6ad07c9019fd 18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
Bethory 0:6ad07c9019fd 19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
Bethory 0:6ad07c9019fd 20 * SOFTWARE.
Bethory 0:6ad07c9019fd 21 */
Bethory 0:6ad07c9019fd 22
Bethory 0:6ad07c9019fd 23 #include "rtos/Kernel.h"
Bethory 0:6ad07c9019fd 24
Bethory 0:6ad07c9019fd 25 #include "mbed.h"
Bethory 0:6ad07c9019fd 26
Bethory 0:6ad07c9019fd 27 namespace rtos {
Bethory 0:6ad07c9019fd 28
Bethory 0:6ad07c9019fd 29 uint64_t Kernel::get_ms_count() {
Bethory 0:6ad07c9019fd 30 // CMSIS-RTOS 2.1.0 and 2.1.1 differ in the time type. We assume
Bethory 0:6ad07c9019fd 31 // our header at least matches the implementation, so we don't try looking
Bethory 0:6ad07c9019fd 32 // at the run-time version report. (There's no compile-time version report)
Bethory 0:6ad07c9019fd 33
Bethory 0:6ad07c9019fd 34 // 2.1.0 uint64_t osKernelGetTickCount(void), not documented as callable from ISR (but RTX does allow)
Bethory 0:6ad07c9019fd 35 // 2.1.1 uint32_t osKernelGetTickCount(void), callable from ISR
Bethory 0:6ad07c9019fd 36 // 2.1.x who knows? We assume could go back to uint64_t
Bethory 0:6ad07c9019fd 37 if (sizeof osKernelGetTickCount() == sizeof(uint64_t)) {
Bethory 0:6ad07c9019fd 38 return osKernelGetTickCount();
Bethory 0:6ad07c9019fd 39 } else /* assume 32-bit */ {
Bethory 0:6ad07c9019fd 40 // Based on suggestion in CMSIS-RTOS 2.1.1 docs, but with reentrancy
Bethory 0:6ad07c9019fd 41 // protection for the tick memory. We use critical section rather than a
Bethory 0:6ad07c9019fd 42 // mutex, as hopefully this method can be callable from interrupt later -
Bethory 0:6ad07c9019fd 43 // only thing currently preventing it is that pre CMSIS RTOS 2.1.1, it's
Bethory 0:6ad07c9019fd 44 // not defined as safe.
Bethory 0:6ad07c9019fd 45 // We assume this is called multiple times per 32-bit wrap period (49 days).
Bethory 0:6ad07c9019fd 46 static uint32_t tick_h, tick_l;
Bethory 0:6ad07c9019fd 47
Bethory 0:6ad07c9019fd 48 core_util_critical_section_enter();
Bethory 0:6ad07c9019fd 49 // The 2.1.1 API says this is legal from an ISR - we assume this means
Bethory 0:6ad07c9019fd 50 // it's also legal with interrupts disabled. RTX implementation kind
Bethory 0:6ad07c9019fd 51 // of conflates the two.
Bethory 0:6ad07c9019fd 52 uint32_t tick32 = osKernelGetTickCount();
Bethory 0:6ad07c9019fd 53 if (tick32 < tick_l) {
Bethory 0:6ad07c9019fd 54 tick_h++;
Bethory 0:6ad07c9019fd 55 }
Bethory 0:6ad07c9019fd 56 tick_l = tick32;
Bethory 0:6ad07c9019fd 57 uint64_t ret = ((uint64_t) tick_h << 32) | tick_l;
Bethory 0:6ad07c9019fd 58 core_util_critical_section_exit();
Bethory 0:6ad07c9019fd 59 return ret;
Bethory 0:6ad07c9019fd 60 }
Bethory 0:6ad07c9019fd 61 }
Bethory 0:6ad07c9019fd 62
Bethory 0:6ad07c9019fd 63 }