X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=cpu%2Fdsp56k%2Fdrv%2Ftimer_dsp56k.h;fp=cpu%2Fdsp56k%2Fdrv%2Ftimer_dsp56k.h;h=f86cb50b2c202aefb5a10111356e04144dbac487;hb=9adb3869a6b8756fbba9ff8a9f7924623e62800d;hp=0000000000000000000000000000000000000000;hpb=059ef38329c43c90936cd9eb36e1ed0cd3b7caea;p=bertos.git diff --git a/cpu/dsp56k/drv/timer_dsp56k.h b/cpu/dsp56k/drv/timer_dsp56k.h new file mode 100644 index 00000000..f86cb50b --- /dev/null +++ b/cpu/dsp56k/drv/timer_dsp56k.h @@ -0,0 +1,148 @@ +#error This code must be revised for the new timer API +/** + * \file + * + * + * \version $Id$ + * + * \author Giovanni Bajo + * + * \brief Driver module for DSP56K + */ + +/*#* + *#* $Log$ + *#* Revision 1.10 2006/07/19 12:56:26 bernie + *#* Convert to new Doxygen style. + *#* + *#* Revision 1.9 2006/02/21 21:28:02 bernie + *#* New time handling based on TIMER_TICKS_PER_SEC to support slow timers with ticks longer than 1ms. + *#* + *#* Revision 1.8 2005/11/04 16:20:02 bernie + *#* Fix reference to README.devlib in header. + *#* + *#* Revision 1.7 2005/04/11 19:10:28 bernie + *#* Include top-level headers from cfg/ subdir. + *#* + *#* Revision 1.6 2004/11/16 22:37:14 bernie + *#* Replace IPTR with iptr_t. + *#* + *#* Revision 1.5 2004/08/25 14:12:08 rasky + *#* Aggiornato il comment block dei log RCS + *#* + *#* Revision 1.4 2004/07/30 14:27:49 rasky + *#* Aggiornati alcuni file DSP56k per la nuova libreria di IRQ management + *#* + *#* Revision 1.3 2004/06/06 18:30:34 bernie + *#* Import DSP56800 changes from SC. + *#* + *#* Revision 1.2 2004/06/03 11:27:09 bernie + *#* Add dual-license information. + *#* + *#* Revision 1.1 2004/05/23 18:23:30 bernie + *#* Import drv/timer module. + *#* + *#*/ + +#ifndef DRV_TIMER_DSP56K_H +#define DRV_TIMER_DSP56K_H + +#include "timer.h" +#include +#include +#include +#include + +// Calculate register pointer and irq vector from hw.h setting +#define REG_SYSTEM_TIMER PP_CAT(REG_TIMER_, SYSTEM_TIMER) +#define SYSTEM_TIMER_IRQ_VECTOR PP_CAT(IRQ_TIMER_, SYSTEM_TIMER) + +/// Prescaler for the system timer +#define TIMER_PRESCALER 16 + +/// Frequency of the hardware high precision timer +#define TIMER_HW_HPTICKS_PER_SEC (IPBUS_FREQ / TIMER_PRESCALER) + +/// Type of time expressed in ticks of the hardware high precision timer +typedef uint16_t hptime_t; + +static void system_timer_isr(UNUSED(iptr_t, arg)); + +static void timer_hw_init(void) +{ + uint16_t compare; + + // Clear compare flag status and enable interrupt on compare + REG_SYSTEM_TIMER->SCR &= ~REG_TIMER_SCR_TCF; + REG_SYSTEM_TIMER->SCR |= REG_TIMER_SCR_TCFIE; + + // Calculate the compare value needed to generate an interrupt exactly + // TICKS_PER_SEC times each second (usually, every millisecond). Check that + // the calculation is accurate, otherwise there is a precision error + // (probably the prescaler is too big or too small). + compare = TIMER_HW_HPTICKS_PER_SEC / TICKS_PER_SEC; + ASSERT((uint32_t)compare * TICKS_PER_SEC == IPBUS_FREQ / TIMER_PRESCALER); + REG_SYSTEM_TIMER->CMP1 = compare; + + // The value for reload (at initializationa and after compare is met) is zero + REG_SYSTEM_TIMER->LOAD = 0; + + // Set the interrupt handler and priority + irq_install(SYSTEM_TIMER_IRQ_VECTOR, &system_timer_isr, NULL); + irq_setpriority(SYSTEM_TIMER_IRQ_VECTOR, IRQ_PRIORITY_SYSTEM_TIMER); + + // Small preprocessor trick to generate the REG_TIMER_CTRL_PRIMARY_IPBYNN macro + // needed to set the prescaler + #define REG_CONTROL_PRESCALER PP_CAT(REG_TIMER_CTRL_PRIMARY_IPBY, TIMER_PRESCALER) + + // Setup the counter and start counting + REG_SYSTEM_TIMER->CTRL = + REG_TIMER_CTRL_MODE_RISING | // count rising edges (normal) + REG_CONTROL_PRESCALER | // frequency (IPbus / TIMER_PRESCALER) + REG_TIMER_CTRL_LENGTH; // up to CMP1, then reload +} + +INLINE void timer_hw_irq(void) +{ + // Clear the overflow flag so that we are ready for another interrupt + REG_SYSTEM_TIMER->SCR &= ~REG_TIMER_SCR_TCF; +} + +INLINE hptime_t timer_hw_hpread(void) +{ + return REG_SYSTEM_TIMER->CNTR; +} + +#define DEFINE_TIMER_ISR \ + static void system_timer_isr(UNUSED(iptr_t, arg)) + +#endif /* DRV_TIMER_DSP56_H */