/* ---------------------------------------------------------------------------- | |
* ATMEL Microcontroller Software Support | |
* ---------------------------------------------------------------------------- | |
* Copyright (c) 2009, Atmel Corporation | |
* | |
* All rights reserved. | |
* | |
* Redistribution and use in source and binary forms, with or without | |
* modification, are permitted provided that the following conditions are met: | |
* | |
* - Redistributions of source code must retain the above copyright notice, | |
* this list of conditions and the disclaimer below. | |
* | |
* Atmel's name may not be used to endorse or promote products derived from | |
* this software without specific prior written permission. | |
* | |
* DISCLAIMER: THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR | |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF | |
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE | |
* DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT, | |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | |
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, | |
* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF | |
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING | |
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, | |
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
* ---------------------------------------------------------------------------- | |
*/ | |
/** | |
* \file | |
* | |
* Provides the low-level initialization function that called on chip startup. | |
*/ | |
/*---------------------------------------------------------------------------- | |
* Headers | |
*----------------------------------------------------------------------------*/ | |
#include "board.h" | |
/*---------------------------------------------------------------------------- | |
* Local definitions | |
*----------------------------------------------------------------------------*/ | |
#define BOARD_OSCOUNT (CKGR_MOR_MOSCXTST(0x8)) | |
#define BOARD_MCKR (PMC_MCKR_PRES_CLK | PMC_MCKR_CSS_PLLA_CLK) | |
#if (BOARD_MCK == 48000000) | |
#if (BOARD_MAINOSC == 18432000) | |
/* Clock settings at 48MHz for 18 MHz crystal */ | |
#define BOARD_PLLAR (CKGR_PLLAR_STUCKTO1 \ | |
| CKGR_PLLAR_MULA(13-1) \ | |
| CKGR_PLLAR_PLLACOUNT(0x1) \ | |
| CKGR_PLLAR_DIVA(5)) | |
#elif (BOARD_MAINOSC == 12000000) | |
/* QMod has 12 MHz clock, so multply by 8 (96 MHz) and divide by 2 */ | |
#define BOARD_PLLAR (CKGR_PLLAR_STUCKTO1 \ | |
| CKGR_PLLAR_MULA(8-1) \ | |
| CKGR_PLLAR_PLLACOUNT(0x1) \ | |
| CKGR_PLLAR_DIVA(2)) | |
#else | |
#error "Please define PLLA config for your MAINOSC frequency" | |
#endif /* MAINOSC */ | |
#elif (BOARD_MCK == 64000000) | |
#if (BOARD_MAINOSC == 18432000) | |
/* Clock settings at 64MHz for 18 MHz crystal: 64.512 MHz */ | |
#define BOARD_PLLAR (CKGR_PLLAR_STUCKTO1 \ | |
| CKGR_PLLAR_MULA(7-1) \ | |
| CKGR_PLLAR_PLLACOUNT(0x1) \ | |
| CKGR_PLLAR_DIVA(2)) | |
#elif (BOARD_MAINOSC == 12000000) | |
/* QMod has 12 MHz clock, so multply by 10 / div by 2: 60 MHz */ | |
#define BOARD_PLLAR (CKGR_PLLAR_STUCKTO1 \ | |
| CKGR_PLLAR_MULA(10-1) \ | |
| CKGR_PLLAR_PLLACOUNT(0x1) \ | |
| CKGR_PLLAR_DIVA(2)) | |
#error "Please define PLLA config for your MAINOSC frequency" | |
#endif /* MAINOSC */ | |
#else | |
#error "No PLL settings for current BOARD_MCK." | |
#endif | |
#if (BOARD_MAINOSC == 12000000) | |
#define PLLB_CFG (CKGR_PLLBR_DIVB(2)|CKGR_PLLBR_MULB(8-1)|CKGR_PLLBR_PLLBCOUNT_Msk) | |
#elif (BOARD_MAINOSC == 18432000) | |
#define PLLB_CFG (CKGR_PLLBR_DIVB(5)|CKGR_PLLBR_MULB(13-1)|CKGR_PLLBR_PLLBCOUNT_Msk) | |
#else | |
#error "Please configure PLLB for your MAINOSC freq" | |
#endif | |
/* Define clock timeout */ | |
#define CLOCK_TIMEOUT 0xFFFFFFFF | |
/** | |
* \brief Configure 48MHz Clock for USB | |
*/ | |
static void _ConfigureUsbClock(void) | |
{ | |
/* Enable PLLB for USB */ | |
PMC->CKGR_PLLBR = PLLB_CFG; | |
while ((PMC->PMC_SR & PMC_SR_LOCKB) == 0) ; | |
/* USB Clock uses PLLB */ | |
PMC->PMC_USB = PMC_USB_USBDIV(0) /* /1 (no divider) */ | |
| PMC_USB_USBS; /* PLLB */ | |
} | |
/*---------------------------------------------------------------------------- | |
* Exported functions | |
*----------------------------------------------------------------------------*/ | |
/** | |
* \brief Performs the low-level initialization of the chip. | |
* This includes EFC and master clock configuration. | |
* It also enable a low level on the pin NRST triggers a user reset. | |
*/ | |
extern WEAK void LowLevelInit( void ) | |
{ | |
uint32_t timeout = 0; | |
/* Configure the Supply Monitor to reset the CPU in case VDDIO is | |
* lower than 3.0V. As we run the board on 3.3V, any lower voltage | |
* might be some kind of leakage that creeps in some way, but is not | |
* the "official" power supply */ | |
SUPC->SUPC_SMMR = SUPC_SMMR_SMTH_3_0V | SUPC_SMMR_SMSMPL_CSM | | |
SUPC_SMMR_SMRSTEN_ENABLE; | |
/* enable both LED and green LED */ | |
PIOA->PIO_PER |= PIO_LED_RED | PIO_LED_GREEN; | |
PIOA->PIO_OER |= PIO_LED_RED | PIO_LED_GREEN; | |
PIOA->PIO_CODR |= PIO_LED_RED | PIO_LED_GREEN; | |
/* Set 3 FWS for Embedded Flash Access */ | |
EFC->EEFC_FMR = EEFC_FMR_FWS(3); | |
/* Select external slow clock */ | |
/* if ((SUPC->SUPC_SR & SUPC_SR_OSCSEL) != SUPC_SR_OSCSEL_CRYST) | |
{ | |
SUPC->SUPC_CR = (uint32_t)(SUPC_CR_XTALSEL_CRYSTAL_SEL | SUPC_CR_KEY(0xA5)); | |
timeout = 0; | |
while (!(SUPC->SUPC_SR & SUPC_SR_OSCSEL_CRYST) ); | |
} | |
*/ | |
#ifndef qmod | |
/* Initialize main oscillator */ | |
if ( !(PMC->CKGR_MOR & CKGR_MOR_MOSCSEL) ) | |
{ | |
PMC->CKGR_MOR = CKGR_MOR_KEY(0x37) | BOARD_OSCOUNT | CKGR_MOR_MOSCRCEN | CKGR_MOR_MOSCXTEN; | |
timeout = 0; | |
while (!(PMC->PMC_SR & PMC_SR_MOSCXTS) && (timeout++ < CLOCK_TIMEOUT)); | |
} | |
/* Switch to 3-20MHz Xtal oscillator */ | |
PIOB->PIO_PDR = (1 << 8) | (1 << 9); | |
PIOB->PIO_PUDR = (1 << 8) | (1 << 9); | |
PIOB->PIO_PPDDR = (1 << 8) | (1 << 9); | |
PMC->CKGR_MOR = CKGR_MOR_KEY(0x37) | BOARD_OSCOUNT | CKGR_MOR_MOSCRCEN | CKGR_MOR_MOSCXTEN | CKGR_MOR_MOSCSEL; | |
/* wait for Main XTAL oscillator stabilization */ | |
timeout = 0; | |
while (!(PMC->PMC_SR & PMC_SR_MOSCSELS) && (timeout++ < CLOCK_TIMEOUT)); | |
#else | |
/* QMOD has external 12MHz clock source */ | |
PIOB->PIO_PDR = (1 << 9); | |
PIOB->PIO_PUDR = (1 << 9); | |
PIOB->PIO_PPDDR = (1 << 9); | |
PMC->CKGR_MOR = CKGR_MOR_KEY(0x37) | CKGR_MOR_MOSCRCEN | CKGR_MOR_MOSCXTBY| CKGR_MOR_MOSCSEL; | |
#endif | |
/* disable the red LED after main clock initialization */ | |
PIOA->PIO_SODR = PIO_LED_RED; | |
/* "switch" to main clock as master clock source (should already be the case */ | |
PMC->PMC_MCKR = (PMC->PMC_MCKR & ~(uint32_t)PMC_MCKR_CSS_Msk) | PMC_MCKR_CSS_MAIN_CLK; | |
/* wait for master clock to be ready */ | |
for ( timeout = 0; !(PMC->PMC_SR & PMC_SR_MCKRDY) && (timeout++ < CLOCK_TIMEOUT) ; ); | |
/* Initialize PLLA */ | |
PMC->CKGR_PLLAR = BOARD_PLLAR; | |
/* Wait for PLLA to lock */ | |
timeout = 0; | |
while (!(PMC->PMC_SR & PMC_SR_LOCKA) && (timeout++ < CLOCK_TIMEOUT)); | |
/* Switch to main clock (again ?!?) */ | |
PMC->PMC_MCKR = (BOARD_MCKR & ~PMC_MCKR_CSS_Msk) | PMC_MCKR_CSS_MAIN_CLK; | |
/* wait for master clock to be ready */ | |
for ( timeout = 0; !(PMC->PMC_SR & PMC_SR_MCKRDY) && (timeout++ < CLOCK_TIMEOUT) ; ); | |
/* switch to PLLA as master clock source */ | |
PMC->PMC_MCKR = BOARD_MCKR ; | |
/* wait for master clock to be ready */ | |
for ( timeout = 0; !(PMC->PMC_SR & PMC_SR_MCKRDY) && (timeout++ < CLOCK_TIMEOUT) ; ); | |
/* Configure SysTick for 1ms */ | |
SysTick_Config(BOARD_MCK/1000); | |
_ConfigureUsbClock(); | |
} | |
/* SysTick based delay function */ | |
volatile uint32_t jiffies; | |
/* Interrupt handler for SysTick interrupt */ | |
void SysTick_Handler(void) | |
{ | |
jiffies++; | |
} | |
void mdelay(unsigned int msecs) | |
{ | |
uint32_t jiffies_start = jiffies; | |
do { | |
} while ((jiffies - jiffies_start) < msecs); | |
} |