Merge pull request #410 from ADVANSEE/cc2538-sys_ctrl

cc2538: sys_ctrl: Make it possible to use the 32-kHz crystal
This commit is contained in:
George Oikonomou 2013-11-15 07:42:45 -08:00
commit d08a87880c
3 changed files with 46 additions and 5 deletions

View file

@ -35,20 +35,39 @@
* \file * \file
* Implementation of the cc2538 System Control driver * Implementation of the cc2538 System Control driver
*/ */
#include "contiki.h"
#include "reg.h" #include "reg.h"
#include "cpu.h" #include "cpu.h"
#include "dev/sys-ctrl.h" #include "dev/sys-ctrl.h"
#include "dev/gpio.h"
#include "dev/ioc.h"
#include <stdint.h> #include <stdint.h>
#if SYS_CTRL_OSC32K_USE_XTAL
#define SYS_CTRL_OSCS 0
#else
#define SYS_CTRL_OSCS SYS_CTRL_CLOCK_CTRL_OSC32K
#endif
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
void void
sys_ctrl_init() sys_ctrl_init()
{ {
uint32_t val; uint32_t val;
#if SYS_CTRL_OSC32K_USE_XTAL
/* Set the XOSC32K_Q pads to analog for crystal */
GPIO_SOFTWARE_CONTROL(GPIO_PORT_TO_BASE(GPIO_D_NUM), GPIO_PIN_MASK(6));
GPIO_SET_INPUT(GPIO_PORT_TO_BASE(GPIO_D_NUM), GPIO_PIN_MASK(6));
ioc_set_over(GPIO_D_NUM, 6, IOC_OVERRIDE_ANA);
GPIO_SOFTWARE_CONTROL(GPIO_PORT_TO_BASE(GPIO_D_NUM), GPIO_PIN_MASK(7));
GPIO_SET_INPUT(GPIO_PORT_TO_BASE(GPIO_D_NUM), GPIO_PIN_MASK(7));
ioc_set_over(GPIO_D_NUM, 7, IOC_OVERRIDE_ANA);
#endif
/* /*
* Desired Clock Ctrl configuration: * Desired Clock Ctrl configuration:
* 32KHz source: RC * 32KHz source: RC or crystal, according to SYS_CTRL_OSC32K_USE_XTAL
* System Clock: 32 MHz * System Clock: 32 MHz
* Power Down Unused * Power Down Unused
* I/O Div: 16MHz * I/O Div: 16MHz
@ -56,11 +75,18 @@ sys_ctrl_init()
* Rest: Don't care * Rest: Don't care
*/ */
val = SYS_CTRL_CLOCK_CTRL_OSC32K | SYS_CTRL_CLOCK_CTRL_OSC_PD val = SYS_CTRL_OSCS | SYS_CTRL_CLOCK_CTRL_OSC_PD
| SYS_CTRL_CLOCK_CTRL_IO_DIV_16MHZ | SYS_CTRL_CLOCK_CTRL_SYS_DIV_16MHZ; | SYS_CTRL_CLOCK_CTRL_IO_DIV_16MHZ | SYS_CTRL_CLOCK_CTRL_SYS_DIV_16MHZ;
REG(SYS_CTRL_CLOCK_CTRL) = val; REG(SYS_CTRL_CLOCK_CTRL) = val;
while((REG(SYS_CTRL_CLOCK_STA) & SYS_CTRL_CLOCK_STA_OSC) != 0); while((REG(SYS_CTRL_CLOCK_STA) & (SYS_CTRL_CLOCK_STA_OSC32K |
SYS_CTRL_CLOCK_STA_OSC)) != SYS_CTRL_OSCS);
#if SYS_CTRL_OSC32K_USE_XTAL
/* Wait for the 32-kHz crystal oscillator to stabilize */
while(REG(SYS_CTRL_CLOCK_STA) & SYS_CTRL_CLOCK_STA_SYNC_32K);
while(!(REG(SYS_CTRL_CLOCK_STA) & SYS_CTRL_CLOCK_STA_SYNC_32K));
#endif
} }
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
void void

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@ -228,11 +228,26 @@
#define SYS_CTRL_PMCTL_PM0 0x00000000 /**< PM0 */ #define SYS_CTRL_PMCTL_PM0 0x00000000 /**< PM0 */
/** @} */ /** @} */
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
/** \name SysCtrl 32-kHz oscillator selection
*
* Prefer the crystal oscillator for time accuracy, and the RC oscillator for
* cost and power consumption
* @{
*/
/* Defaults to RC oscillator unless the configuration tells us otherwise */
#ifdef SYS_CTRL_CONF_OSC32K_USE_XTAL
#define SYS_CTRL_OSC32K_USE_XTAL SYS_CTRL_CONF_OSC32K_USE_XTAL
#else
#define SYS_CTRL_OSC32K_USE_XTAL 0
#endif
/** @} */
/*---------------------------------------------------------------------------*/
/** \name SysCtrl functions /** \name SysCtrl functions
* @{ * @{
*/ */
/** \brief Initialises the System Control Driver. The main purpose of this /** \brief Initialises the System Control Driver. The main purpose of this
* function is to power up and select clocks and oscillators */ * function is to power up and select clocks and oscillators
* \note This function depends on ioc_init() having been called beforehand. */
void sys_ctrl_init(); void sys_ctrl_init();
/** \brief Generates a warm reset through the SYS_CTRL_PWRDBG register */ /** \brief Generates a warm reset through the SYS_CTRL_PWRDBG register */

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@ -127,12 +127,12 @@ int
main(void) main(void)
{ {
nvic_init(); nvic_init();
ioc_init();
sys_ctrl_init(); sys_ctrl_init();
clock_init(); clock_init();
lpm_init(); lpm_init();
rtimer_init(); rtimer_init();
gpio_init(); gpio_init();
ioc_init();
leds_init(); leds_init();
fade(LEDS_YELLOW); fade(LEDS_YELLOW);