panda-meb/board/libc.h

#define min(a,b) \
 ({ __typeof__ (a) _a = (a); \
     __typeof__ (b) _b = (b); \
   _a < _b ? _a : _b; })

#define max(a,b) \
 ({ __typeof__ (a) _a = (a); \
     __typeof__ (b) _b = (b); \
   _a > _b ? _a : _b; })

// **** shitty libc ****

void clock_init() {
  #ifdef USE_INTERNAL_OSC
    // enable internal oscillator
    RCC->CR |= RCC_CR_HSION;
    while ((RCC->CR & RCC_CR_HSIRDY) == 0);
  #else
    // enable external oscillator
    RCC->CR |= RCC_CR_HSEON;
    while ((RCC->CR & RCC_CR_HSERDY) == 0);
  #endif

  // divide shit
  RCC->CFGR = RCC_CFGR_HPRE_DIV1 | RCC_CFGR_PPRE2_DIV2 | RCC_CFGR_PPRE1_DIV4;
  #ifdef USE_INTERNAL_OSC
    RCC->PLLCFGR = RCC_PLLCFGR_PLLQ_2 | RCC_PLLCFGR_PLLM_3 |
                   RCC_PLLCFGR_PLLN_6 | RCC_PLLCFGR_PLLN_5 | RCC_PLLCFGR_PLLSRC_HSI;
  #else
    #ifdef PANDA
      RCC->PLLCFGR = RCC_PLLCFGR_PLLQ_2 | RCC_PLLCFGR_PLLM_3 |
                     RCC_PLLCFGR_PLLN_6 | RCC_PLLCFGR_PLLN_5 | RCC_PLLCFGR_PLLSRC_HSE;
    #else
      RCC->PLLCFGR = RCC_PLLCFGR_PLLQ_2 | RCC_PLLCFGR_PLLM_3 |
                     RCC_PLLCFGR_PLLN_7 | RCC_PLLCFGR_PLLN_6 | RCC_PLLCFGR_PLLSRC_HSE;
    #endif
  #endif

  // start PLL
  RCC->CR |= RCC_CR_PLLON;
  while ((RCC->CR & RCC_CR_PLLRDY) == 0);

  // Configure Flash prefetch, Instruction cache, Data cache and wait state
  // *** without this, it breaks ***
  FLASH->ACR = FLASH_ACR_ICEN | FLASH_ACR_DCEN | FLASH_ACR_LATENCY_5WS;

  // switch to PLL
  RCC->CFGR |= RCC_CFGR_SW_PLL;
  while ((RCC->CFGR & RCC_CFGR_SWS) != RCC_CFGR_SWS_PLL);

  // *** running on PLL ***
}


void delay(int a) {
  volatile int i;
  for (i=0;i<a;i++);
}

void *memset(void *str, int c, unsigned int n) {
  int i;
  for (i = 0; i < n; i++) {
    *((uint8_t*)str) = c;
    ++str;
  }
  return str;
}

void *memcpy(void *dest, const void *src, unsigned int n) {
  int i;
  // TODO: make not slow
  for (i = 0; i < n; i++) {
    ((uint8_t*)dest)[i] = *(uint8_t*)src;
    ++src;
  }
  return dest;
}