/**
* @brief Configure the controllers clock system
*/
static void cpu_clock_init(void)
{
/* setup system prescalers */
SIM->CLKDIV1 = (uint32_t)SIM_CLKDIV1_OUTDIV4(1);
modem_clock_init();
kinetis_mcg_set_mode(KINETIS_MCG_PEE);
}
void board_init(void)
{
/* initialize the boards LEDs, this is done first for debugging purposes */
leds_init();
/* Initialize power control pins */
power_pins_init();
/* Turn on Vperiph for peripherals */
gpio_set(MULLE_POWER_VPERIPH);
/* Turn on AVDD for reading voltages */
gpio_set(MULLE_POWER_AVDD);
LED_RED_ON;
/* Initialize RTC oscillator as early as possible since we are using it as a
* base clock for the FLL.
* It takes a while to stabilize the oscillator, therefore we do this as
* soon as possible during boot in order to let it stabilize while other
* stuff is initializing. */
/* If the clock is not stable then the UART will have the wrong baud rate
* for debug prints as well */
rtt_init();
/* Set up clocks */
set_safe_clock_dividers();
set_fll_source();
kinetis_mcg_set_mode(KINETIS_MCG_FEE);
/* At this point we need to wait for 1 ms until the clock is stable.
* Since the clock is not yet stable we can only guess how long we must
* wait. I have tried to make this as short as possible but still being able
* to read the initialization messages written on the UART.
* (If the clock is not stable all UART output is garbled until it has
* stabilized) */
for (int i = 0; i < 100000; ++i) {
asm volatile("nop\n");
}
/* Update SystemCoreClock global var */
SystemCoreClockUpdate();
/* initialize the CPU */
cpu_init();
}
/**
* @brief Configure the controllers clock system
*/
static void cpu_clock_init(void)
{
/* setup system prescalers */
SIM->CLKDIV1 = (uint32_t)SIM_CLKDIV1_OUTDIV4(1);
modem_clock_init();
kinetis_mcg_set_mode(KINETIS_MCG_PEE);
/*
* Setup USBFSOTG clock
* USB clock should be 48 MHz, use MCGPLLCLK as clock source
* usb_clk = (pll_clk * 1 / 1) = 48MHz * 1 / 1 = 48MHz
*/
#if MODULE_USBDEV
SIM->SOPT2 &= ~(SIM_SOPT2_USBSRC_MASK | SIM_SOPT2_PLLFLLSEL_MASK);
SIM->SOPT2 |= SIM_SOPT2_USBSRC_MASK | SIM_SOPT2_PLLFLLSEL_MASK;
SIM->CLKDIV2 = 0;
#endif
}
void board_init(void)
{
int status;
/* initialize the boards LEDs */
gpio_init(LED0_PIN, GPIO_OUT);
gpio_init(LED1_PIN, GPIO_OUT);
gpio_init(LED2_PIN, GPIO_OUT);
/* Initialize power control pins */
power_pins_init();
/* Turn on Vperiph for peripherals */
/*
* By turning on Vperiph first, and before waiting for the clocks to
* stabilize, we will have used enough time to have let the FRAM start up
* properly when we want to access it later without having to add any extra
* delays.
*/
gpio_set(MULLE_POWER_VPERIPH);
/* Turn on AVDD for reading voltages */
gpio_set(MULLE_POWER_AVDD);
/* Initialize RTC oscillator as early as possible since we are using it as a
* base clock for the FLL.
* It takes a while to stabilize the oscillator, therefore we do this as
* soon as possible during boot in order to let it stabilize while other
* stuff is initializing. */
/* If the clock is not stable then the UART will have the wrong baud rate
* for debug prints as well */
rtt_init();
/* Set up clocks */
set_safe_clock_dividers();
set_fll_source();
kinetis_mcg_set_mode(KINETIS_MCG_FEE);
/* At this point we need to wait for 1 ms until the clock is stable.
* Since the clock is not yet stable we can only guess how long we must
* wait. I have tried to make this as short as possible but still being able
* to read the initialization messages written on the UART.
* (If the clock is not stable all UART output is garbled until it has
* stabilized) */
for (int i = 0; i < 100000; ++i) {
__asm__ volatile("nop\n");
}
/* Update SystemCoreClock global var */
SystemCoreClockUpdate();
/* initialize the CPU */
cpu_init();
/* NVRAM requires xtimer for timing */
xtimer_init();
/* Initialize NVRAM */
status = mulle_nvram_init();
if (status == 0) {
/* Increment boot counter */
increase_boot_count();
}
}
