1 /* 2 * SPDX-FileCopyrightText: 2015-2019 Cadence Design Systems, Inc. 3 * 4 * SPDX-License-Identifier: MIT 5 * 6 * SPDX-FileContributor: 2016-2022 Espressif Systems (Shanghai) CO LTD 7 */ 8 9 /* 10 * Copyright (c) 2015-2019 Cadence Design Systems, Inc. 11 * 12 * Permission is hereby granted, free of charge, to any person obtaining 13 * a copy of this software and associated documentation files (the 14 * "Software"), to deal in the Software without restriction, including 15 * without limitation the rights to use, copy, modify, merge, publish, 16 * distribute, sublicense, and/or sell copies of the Software, and to 17 * permit persons to whom the Software is furnished to do so, subject to 18 * the following conditions: 19 * 20 * The above copyright notice and this permission notice shall be included 21 * in all copies or substantial portions of the Software. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 26 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 27 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 28 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 29 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 30 */ 31 32 /******************************************************************************* 33 * 34 * XTENSA INFORMATION FOR RTOS TICK TIMER AND CLOCK FREQUENCY 35 * 36 * This header contains definitions and macros for use primarily by Xtensa 37 * RTOS assembly coded source files. It includes and uses the Xtensa hardware 38 * abstraction layer (HAL) to deal with config specifics. It may also be 39 * included in C source files. 40 * 41 * User may edit to modify timer selection and to specify clock frequency and 42 * tick duration to match timer interrupt to the real-time tick duration. 43 * 44 * If the RTOS has no timer interrupt, then there is no tick timer and the 45 * clock frequency is irrelevant, so all of these macros are left undefined 46 * and the Xtensa core configuration need not have a timer. 47 * 48 *******************************************************************************/ 49 50 #ifndef XTENSA_TIMER_H 51 #define XTENSA_TIMER_H 52 53 #ifdef __ASSEMBLER__ 54 #include <xtensa/coreasm.h> 55 #endif 56 57 #include <xtensa/corebits.h> 58 #include <xtensa/config/system.h> 59 60 #include "xtensa_rtos.h" /* in case this wasn't included directly */ 61 62 #include "FreeRTOSConfig.h" 63 64 /* 65 * Select timer to use for periodic tick, and determine its interrupt number 66 * and priority. User may specify a timer by defining XT_TIMER_INDEX with -D, 67 * in which case its validity is checked (it must exist in this core and must 68 * not be on a high priority interrupt - an error will be reported in invalid). 69 * Otherwise select the first low or medium priority interrupt timer available. 70 */ 71 #if XCHAL_NUM_TIMERS == 0 72 73 #error "This Xtensa configuration is unsupported, it has no timers." 74 75 #else 76 77 #ifndef XT_TIMER_INDEX 78 #if XCHAL_TIMER3_INTERRUPT != XTHAL_TIMER_UNCONFIGURED 79 #if XCHAL_INT_LEVEL( XCHAL_TIMER3_INTERRUPT ) <= XCHAL_EXCM_LEVEL 80 #undef XT_TIMER_INDEX 81 #define XT_TIMER_INDEX 3 82 #endif 83 #endif 84 #if XCHAL_TIMER2_INTERRUPT != XTHAL_TIMER_UNCONFIGURED 85 #if XCHAL_INT_LEVEL( XCHAL_TIMER2_INTERRUPT ) <= XCHAL_EXCM_LEVEL 86 #undef XT_TIMER_INDEX 87 #define XT_TIMER_INDEX 2 88 #endif 89 #endif 90 #if XCHAL_TIMER1_INTERRUPT != XTHAL_TIMER_UNCONFIGURED 91 #if XCHAL_INT_LEVEL( XCHAL_TIMER1_INTERRUPT ) <= XCHAL_EXCM_LEVEL 92 #undef XT_TIMER_INDEX 93 #define XT_TIMER_INDEX 1 94 #endif 95 #endif 96 #if XCHAL_TIMER0_INTERRUPT != XTHAL_TIMER_UNCONFIGURED 97 #if XCHAL_INT_LEVEL( XCHAL_TIMER0_INTERRUPT ) <= XCHAL_EXCM_LEVEL 98 #undef XT_TIMER_INDEX 99 #define XT_TIMER_INDEX 0 100 #endif 101 #endif 102 #endif /* ifndef XT_TIMER_INDEX */ 103 #ifndef XT_TIMER_INDEX 104 #error "There is no suitable timer in this Xtensa configuration." 105 #endif 106 107 #define XT_CCOMPARE ( CCOMPARE + XT_TIMER_INDEX ) 108 #define XT_TIMER_INTNUM XCHAL_TIMER_INTERRUPT( XT_TIMER_INDEX ) 109 #define XT_TIMER_INTPRI XCHAL_INT_LEVEL( XT_TIMER_INTNUM ) 110 #define XT_TIMER_INTEN ( 1 << XT_TIMER_INTNUM ) 111 112 #if XT_TIMER_INTNUM == XTHAL_TIMER_UNCONFIGURED 113 #error "The timer selected by XT_TIMER_INDEX does not exist in this core." 114 #elif XT_TIMER_INTPRI > XCHAL_EXCM_LEVEL 115 #error "The timer interrupt cannot be high priority (use medium or low)." 116 #endif 117 118 #endif /* XCHAL_NUM_TIMERS */ 119 120 /* 121 * Set processor clock frequency, used to determine clock divisor for timer tick. 122 * User should BE SURE TO ADJUST THIS for the Xtensa platform being used. 123 * If using a supported board via the board-independent API defined in xtbsp.h, 124 * this may be left undefined and frequency and tick divisor will be computed 125 * and cached during run-time initialization. 126 * 127 * NOTE ON SIMULATOR: 128 * Under the Xtensa instruction set simulator, the frequency can only be estimated 129 * because it depends on the speed of the host and the version of the simulator. 130 * Also because it runs much slower than hardware, it is not possible to achieve 131 * real-time performance for most applications under the simulator. A frequency 132 * too low does not allow enough time between timer interrupts, starving threads. 133 * To obtain a more convenient but non-real-time tick duration on the simulator, 134 * compile with xt-xcc option "-DXT_SIMULATOR". 135 * Adjust this frequency to taste (it's not real-time anyway!). 136 */ 137 #if defined( XT_SIMULATOR ) && !defined( XT_CLOCK_FREQ ) 138 #define XT_CLOCK_FREQ configCPU_CLOCK_HZ 139 #endif 140 141 #if !defined( XT_CLOCK_FREQ ) && !defined( XT_BOARD ) 142 #error "XT_CLOCK_FREQ must be defined for the target platform." 143 #endif 144 145 /* 146 * Default number of timer "ticks" per second (default 100 for 10ms tick). 147 * RTOS may define this in its own way (if applicable) in xtensa_rtos.h. 148 * User may redefine this to an optimal value for the application, either by 149 * editing this here or in xtensa_rtos.h, or compiling with xt-xcc option 150 * "-DXT_TICK_PER_SEC=<value>" where <value> is a suitable number. 151 */ 152 #ifndef XT_TICK_PER_SEC 153 #define XT_TICK_PER_SEC configTICK_RATE_HZ /* 10 ms tick = 100 ticks per second */ 154 #endif 155 156 /* 157 * Derivation of clock divisor for timer tick and interrupt (one per tick). 158 */ 159 #ifdef XT_CLOCK_FREQ 160 #define XT_TICK_DIVISOR ( XT_CLOCK_FREQ / XT_TICK_PER_SEC ) 161 #endif 162 163 #ifndef __ASSEMBLER__ 164 extern unsigned _xt_tick_divisor; 165 extern void _xt_tick_divisor_init( void ); 166 #endif 167 168 #endif /* XTENSA_TIMER_H */ 169
