src/main/drivers/system.c

   1 /*
   2  * This file is part of Cleanflight and Betaflight.
   3  *
   4  * Cleanflight and Betaflight are free software. You can redistribute
   5  * this software and/or modify this software under the terms of the
   6  * GNU General Public License as published by the Free Software
   7  * Foundation, either version 3 of the License, or (at your option)
   8  * any later version.
   9  *
  10  * Cleanflight and Betaflight are distributed in the hope that they
  11  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  12  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  13  * See the GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this software.
  17  *
  18  * If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <stdbool.h>
  22 #include <stdint.h>
  23 #include <string.h>
  24
  25 #include "platform.h"
  26
  27 #include "build/atomic.h"
  28
  29 #include "drivers/io.h"
  30 #include "drivers/light_led.h"
  31 #include "drivers/nvic.h"
  32 #include "drivers/resource.h"
  33 #include "drivers/sound_beeper.h"
  34
  35
  36 #include "system.h"
  37
  38 #if defined(STM32F4) || defined(STM32F7) || defined(STM32H7)
  39 // See "RM CoreSight Architecture Specification"
  40 // B2.3.10  "LSR and LAR, Software Lock Status Register and Software Lock Access Register"
  41 // "E1.2.11  LAR, Lock Access Register"
  42
  43 #define DWT_LAR_UNLOCK_VALUE 0xC5ACCE55
  44
  45 #endif
  46
  47 // cycles per microsecond
  48 static uint32_t usTicks = 0;
  49 // current uptime for 1kHz systick timer. will rollover after 49 days. hopefully we won't care.
  50 static volatile uint32_t sysTickUptime = 0;
  51 static volatile uint32_t sysTickValStamp = 0;
  52 // cached value of RCC->CSR
  53 uint32_t cachedRccCsrValue;
  54 static uint32_t cpuClockFrequency = 0;
  55
  56 void cycleCounterInit(void)
  57 {
  58 #if defined(USE_HAL_DRIVER)
  59     cpuClockFrequency = HAL_RCC_GetSysClockFreq();
  60 #else
  61     RCC_ClocksTypeDef clocks;
  62     RCC_GetClocksFreq(&clocks);
  63     cpuClockFrequency = clocks.SYSCLK_Frequency;
  64 #endif
  65     usTicks = cpuClockFrequency / 1000000;
  66
  67     CoreDebug->DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
  68
  69 #if defined(DWT_LAR_UNLOCK_VALUE)
  70 #if defined(STM32H7)
  71     ITM->LAR = DWT_LAR_UNLOCK_VALUE;
  72 #elif defined(STM32F7)
  73     DWT->LAR = DWT_LAR_UNLOCK_VALUE;
  74 #elif defined(STM32F4)
  75     // Note: DWT_Type does not contain LAR member.
  76 #define DWT_LAR
  77     __O uint32_t *DWTLAR = (uint32_t *)(DWT_BASE + 0x0FB0);
  78     *(DWTLAR) = DWT_LAR_UNLOCK_VALUE;
  79 #endif
  80 #endif
  81
  82     DWT->CYCCNT = 0;
  83     DWT->CTRL |= DWT_CTRL_CYCCNTENA_Msk;
  84 }
  85
  86 // SysTick
  87
  88 static volatile int sysTickPending = 0;
  89
  90 void SysTick_Handler(void)
  91 {
  92     ATOMIC_BLOCK(NVIC_PRIO_MAX) {
  93         sysTickUptime++;
  94         sysTickValStamp = SysTick->VAL;
  95         sysTickPending = 0;
  96         (void)(SysTick->CTRL);
  97     }
  98 #ifdef USE_HAL_DRIVER
  99     // used by the HAL for some timekeeping and timeouts, should always be 1ms
 100     HAL_IncTick();
 101 #endif
 102 }
 103
 104 // Return system uptime in microseconds (rollover in 70minutes)
 105
 106 uint32_t microsISR(void)
 107 {
 108     register uint32_t ms, pending, cycle_cnt;
 109
 110     ATOMIC_BLOCK(NVIC_PRIO_MAX) {
 111         cycle_cnt = SysTick->VAL;
 112
 113         if (SysTick->CTRL & SysTick_CTRL_COUNTFLAG_Msk) {
 114             // Update pending.
 115             // Record it for multiple calls within the same rollover period
 116             // (Will be cleared when serviced).
 117             // Note that multiple rollovers are not considered.
 118
 119             sysTickPending = 1;
 120
 121             // Read VAL again to ensure the value is read after the rollover.
 122
 123             cycle_cnt = SysTick->VAL;
 124         }
 125
 126         ms = sysTickUptime;
 127         pending = sysTickPending;
 128     }
 129
 130     return ((ms + pending) * 1000) + (usTicks * 1000 - cycle_cnt) / usTicks;
 131 }
 132
 133 uint32_t micros(void)
 134 {
 135     register uint32_t ms, cycle_cnt;
 136
 137     // Call microsISR() in interrupt and elevated (non-zero) BASEPRI context
 138
 139     if ((SCB->ICSR & SCB_ICSR_VECTACTIVE_Msk) || (__get_BASEPRI())) {
 140         return microsISR();
 141     }
 142
 143     do {
 144         ms = sysTickUptime;
 145         cycle_cnt = SysTick->VAL;
 146     } while (ms != sysTickUptime || cycle_cnt > sysTickValStamp);
 147
 148     return (ms * 1000) + (usTicks * 1000 - cycle_cnt) / usTicks;
 149 }
 150
 151 uint32_t getCycleCounter(void)
 152 {
 153     return DWT->CYCCNT;
 154 }
 155
 156 int32_t clockCyclesToMicros(int32_t clockCycles)
 157 {
 158     return clockCycles / usTicks;
 159 }
 160
 161 // Note that this conversion is signed as this is used for periods rather than absolute timestamps
 162 int32_t clockCyclesTo10thMicros(int32_t clockCycles)
 163 {
 164     return 10 * clockCycles / (int32_t)usTicks;
 165 }
 166
 167 uint32_t clockMicrosToCycles(uint32_t micros)
 168 {
 169     return micros * usTicks;
 170 }
 171
 172 // Return system uptime in milliseconds (rollover in 49 days)
 173 uint32_t millis(void)
 174 {
 175     return sysTickUptime;
 176 }
 177
 178 #if 1
 179 void delayMicroseconds(uint32_t us)
 180 {
 181     uint32_t now = micros();
 182     while (micros() - now < us);
 183 }
 184 #else
 185 void delayMicroseconds(uint32_t us)
 186 {
 187     uint32_t elapsed = 0;
 188     uint32_t lastCount = SysTick->VAL;
 189
 190     for (;;) {
 191         register uint32_t current_count = SysTick->VAL;
 192         uint32_t elapsed_us;
 193
 194         // measure the time elapsed since the last time we checked
 195         elapsed += current_count - lastCount;
 196         lastCount = current_count;
 197
 198         // convert to microseconds
 199         elapsed_us = elapsed / usTicks;
 200         if (elapsed_us >= us)
 201             break;
 202
 203         // reduce the delay by the elapsed time
 204         us -= elapsed_us;
 205
 206         // keep fractional microseconds for the next iteration
 207         elapsed %= usTicks;
 208     }
 209 }
 210 #endif
 211
 212 void delay(uint32_t ms)
 213 {
 214     while (ms--)
 215         delayMicroseconds(1000);
 216 }
 217
 218 static void indicate(uint8_t count, uint16_t duration)
 219 {
 220     if (count) {
 221         LED1_ON;
 222         LED0_OFF;
 223
 224         while (count--) {
 225             LED1_TOGGLE;
 226             LED0_TOGGLE;
 227             BEEP_ON;
 228             delay(duration);
 229
 230             LED1_TOGGLE;
 231             LED0_TOGGLE;
 232             BEEP_OFF;
 233             delay(duration);
 234         }
 235     }
 236 }
 237
 238 void indicateFailure(failureMode_e mode, int codeRepeatsRemaining)
 239 {
 240     while (codeRepeatsRemaining--) {
 241         indicate(WARNING_FLASH_COUNT, WARNING_FLASH_DURATION_MS);
 242
 243         delay(WARNING_PAUSE_DURATION_MS);
 244
 245         indicate(mode + 1, WARNING_CODE_DURATION_LONG_MS);
 246
 247         delay(1000);
 248     }
 249 }
 250
 251 void failureMode(failureMode_e mode)
 252 {
 253     indicateFailure(mode, 10);
 254
 255 #ifdef DEBUG
 256     systemReset();
 257 #else
 258     systemResetToBootloader(BOOTLOADER_REQUEST_ROM);
 259 #endif
 260 }
 261
 262 void initialiseMemorySections(void)
 263 {
 264 #ifdef USE_ITCM_RAM
 265     /* Load functions into ITCM RAM */
 266     extern uint8_t tcm_code_start;
 267     extern uint8_t tcm_code_end;
 268     extern uint8_t tcm_code;
 269     memcpy(&tcm_code_start, &tcm_code, (size_t) (&tcm_code_end - &tcm_code_start));
 270 #endif
 271
 272 #ifdef USE_CCM_CODE
 273     /* Load functions into RAM */
 274     extern uint8_t ccm_code_start;
 275     extern uint8_t ccm_code_end;
 276     extern uint8_t ccm_code;
 277     memcpy(&ccm_code_start, &ccm_code, (size_t) (&ccm_code_end - &ccm_code_start));
 278 #endif
 279
 280 #ifdef USE_FAST_DATA
 281     /* Load FAST_DATA variable initializers into DTCM RAM */
 282     extern uint8_t _sfastram_data;
 283     extern uint8_t _efastram_data;
 284     extern uint8_t _sfastram_idata;
 285     memcpy(&_sfastram_data, &_sfastram_idata, (size_t) (&_efastram_data - &_sfastram_data));
 286 #endif
 287 }
 288
 289 #ifdef STM32H7
 290 void initialiseD2MemorySections(void)
 291 {
 292     /* Load DMA_DATA variable intializers into D2 RAM */
 293     extern uint8_t _sdmaram_bss;
 294     extern uint8_t _edmaram_bss;
 295     extern uint8_t _sdmaram_data;
 296     extern uint8_t _edmaram_data;
 297     extern uint8_t _sdmaram_idata;
 298     bzero(&_sdmaram_bss, (size_t) (&_edmaram_bss - &_sdmaram_bss));
 299     memcpy(&_sdmaram_data, &_sdmaram_idata, (size_t) (&_edmaram_data - &_sdmaram_data));
 300 }
 301 #endif
 302
 303 static void unusedPinInit(IO_t io)
 304 {
 305     if (IOGetOwner(io) == OWNER_FREE) {
 306         IOConfigGPIO(io, IOCFG_IPU);
 307     }
 308 }
 309
 310 void unusedPinsInit(void)
 311 {
 312     IOTraversePins(unusedPinInit);
 313 }