static void mpc55xx_clock_initialize(void)
{
volatile struct EMIOS_CH_tag *regs = &EMIOS.CH [MPC55XX_CLOCK_EMIOS_CHANNEL];
union EMIOS_CCR_tag ccr = MPC55XX_ZERO_FLAGS;
union EMIOS_CSR_tag csr = MPC55XX_ZERO_FLAGS;
unsigned prescaler = mpc55xx_emios_global_prescaler();
uint64_t reference_clock = bsp_clock_speed;
uint64_t us_per_tick = rtems_configuration_get_microseconds_per_tick();
uint64_t interval = (reference_clock * us_per_tick) / 1000000;
/* Apply prescaler */
if (prescaler > 0) {
interval /= (uint64_t) prescaler;
} else {
bsp_fatal(MPC55XX_FATAL_CLOCK_EMIOS_PRESCALER);
}
/* Check interval */
if (interval == 0 || interval > MPC55XX_EMIOS_VALUE_MAX) {
bsp_fatal(MPC55XX_FATAL_CLOCK_EMIOS_INTERVAL);
}
/* Configure eMIOS channel */
/* Set channel in GPIO mode */
ccr.B.MODE = MPC55XX_EMIOS_MODE_GPIO_INPUT;
regs->CCR.R = ccr.R;
/* Clear status flags */
csr.B.OVR = 1;
csr.B.OVFL = 1;
csr.B.FLAG = 1;
regs->CSR.R = csr.R;
/* Set internal counter start value */
regs->CCNTR.R = 1;
/* Set timer period */
regs->CADR.R = (uint32_t) interval - 1;
/* Set control register */
#if MPC55XX_CHIP_FAMILY == 551
ccr.B.MODE = MPC55XX_EMIOS_MODE_MCB_UP_INT_CLK;
#else
ccr.B.MODE = MPC55XX_EMIOS_MODE_MC_UP_INT_CLK;
#endif
ccr.B.UCPREN = 1;
ccr.B.FEN = 1;
ccr.B.FREN = 1;
regs->CCR.R = ccr.R;
rtems_timecounter_simple_install(
&mpc55xx_tc,
reference_clock,
interval,
mpc55xx_tc_get_timecount
);
}
static void mpc55xx_clock_initialize( void)
{
volatile struct EMIOS_CH_tag *regs = &EMIOS.CH [MPC55XX_CLOCK_EMIOS_CHANNEL];
union EMIOS_CCR_tag ccr = MPC55XX_ZERO_FLAGS;
union EMIOS_CSR_tag csr = MPC55XX_ZERO_FLAGS;
unsigned prescaler = mpc55xx_emios_global_prescaler();
uint64_t interval = ((uint64_t) bsp_clock_speed
* (uint64_t) rtems_configuration_get_microseconds_per_tick()) / 1000000;
/* Apply prescaler */
if (prescaler > 0) {
interval /= (uint64_t) prescaler;
} else {
RTEMS_SYSLOG_ERROR( "unexpected global eMIOS prescaler\n");
}
/* Check interval */
if (interval == 0 || interval > MPC55XX_EMIOS_VALUE_MAX) {
interval = MPC55XX_EMIOS_VALUE_MAX;
RTEMS_SYSLOG_ERROR( "clock timer interval out of range\n");
}
/* Configure eMIOS channel */
/* Set channel in GPIO mode */
ccr.B.MODE = MPC55XX_EMIOS_MODE_GPIO_INPUT;
regs->CCR.R = ccr.R;
/* Clear status flags */
csr.B.OVR = 1;
csr.B.OVFL = 1;
csr.B.FLAG = 1;
regs->CSR.R = csr.R;
/* Set timer period */
regs->CADR.R = (uint32_t) interval - 1;
/* Set unused registers */
regs->CBDR.R = 0;
regs->CCNTR.R = 0;
regs->ALTCADR.R = 0;
/* Set control register */
ccr.B.MODE = MPC55XX_EMIOS_MODE_MCB_UP_INT_CLK;
ccr.B.UCPREN = 1;
ccr.B.FEN = 1;
ccr.B.FREN = 1;
regs->CCR.R = ccr.R;
}