Merge from kseries.
[bertos.git] / drv / timer_avr.h
index 296215db3625001841ae395bf1a0a1f370d798c8..0155ecc7d9a0287b2310b26b50b77fda1103017e 100755 (executable)
-/*!
+/**
  * \file
  * <!--
- * Copyright 2003,2004 Develer S.r.l. (http://www.develer.com/)
+ * Copyright 2003, 2004, 2005 Develer S.r.l. (http://www.develer.com/)
  * Copyright 2000 Bernardo Innocenti <bernie@develer.com>
- * This file is part of DevLib - See devlib/README for information.
+ * This file is part of DevLib - See README.devlib for information.
  * -->
  *
  * \version $Id$
  *
  * \author Bernardo Innocenti <bernie@develer.com>
+ * \author Francesco Sacchi <batt@develer.com>
  *
- * \brief Low-level timer module for AVR
+ * \brief Low-level timer module for AVR (interface).
  */
 
-/*
- * $Log$
- * Revision 1.2  2004/06/03 11:27:09  bernie
- * Add dual-license information.
+/*#*
+ *#* $Log$
+ *#* Revision 1.30  2007/06/07 14:35:12  batt
+ *#* Merge from project_ks.
+ *#*
+ *#* Revision 1.29  2007/03/21 11:01:36  batt
+ *#* Add missing support for ATMega1281.
+ *#*
+ *#* Revision 1.28  2006/07/19 12:56:26  bernie
+ *#* Convert to new Doxygen style.
+ *#*
+ *#* Revision 1.27  2006/05/18 00:38:24  bernie
+ *#* Use hw_cpu.h instead of ubiquitous hw.h.
+ *#*
+ *#* Revision 1.26  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 1.25  2005/07/19 07:26:37  bernie
+ *#* Refactor to decouple timer ticks from milliseconds.
+ *#*
+ *#* Revision 1.24  2005/04/11 19:10:28  bernie
+ *#* Include top-level headers from cfg/ subdir.
+ *#*
+ *#* Revision 1.23  2005/03/01 23:24:51  bernie
+ *#* Tweaks for avr-libc 1.2.x.
+ *#*
+ *#* Revision 1.21  2004/12/13 12:07:06  bernie
+ *#* DISABLE_IRQSAVE/ENABLE_IRQRESTORE: Convert to IRQ_SAVE_DISABLE/IRQ_RESTORE.
+ *#*
+ *#* Revision 1.20  2004/11/16 20:59:46  bernie
+ *#* Include <avr/io.h> explicitly.
+ *#*
+ *#* Revision 1.19  2004/10/19 08:56:41  bernie
+ *#* TIMER_STROBE_ON, TIMER_STROBE_OFF, TIMER_STROBE_INIT: Move from timer_avr.h to timer.h, where they really belong.
+ *#*
+ *#* Revision 1.18  2004/09/20 03:31:03  bernie
+ *#* Fix racy racy code.
+ *#*/
+#ifndef DRV_TIMER_AVR_H
+#define DRV_TIMER_AVR_H
+
+#include <appconfig.h>     /* CONFIG_TIMER */
+#include <cfg/compiler.h>  /* uint8_t */
+#include <hw_cpu.h>        /* CLOCK_FREQ */
+
+/**
+ * \name Values for CONFIG_TIMER.
  *
- * Revision 1.1  2004/05/23 18:23:30  bernie
- * Import drv/timer module.
+ * Select which hardware timer interrupt to use for system clock and softtimers.
+ * \note The timer 1 overflow mode set the timer as a 24 kHz PWM.
  *
+ * \{
  */
+#define TIMER_ON_OUTPUT_COMPARE0  1
+#define TIMER_ON_OVERFLOW1        2
+#define TIMER_ON_OUTPUT_COMPARE2  3
+#define TIMER_ON_OVERFLOW3        4
+/* \} */
 
-#ifndef DRV_TIMER_AVR_H
-#define DRV_TIMER_AVR_H
-
-#include <avr/wdt.h>
-
-#      define TIMER_RETRIGGER /* Not needed, timer retriggers automatically  */
-
-       /*!
-        * System timer: additional division after the prescaler
-        * 12288000 / 64 / 192 (0..191) = 1 ms
-        */
-#      define OCR_DIVISOR 191
-
-       /*! HW dependent timer initialization  */
-#if defined(CONFIG_TIMER_ON_TIMER0)
-
-#              define TIMER_INIT \
-               do { \
-                       DISABLE_INTS; \
-                       \
-                       /* Reset Timer flags */ \
-                       TIFR = BV(OCF0) | BV(TOV0); \
-                       \
-                       /* Setup Timer/Counter interrupt */ \
-                       ASSR = 0x00;                  /* internal system clock */ \
-                       TCCR0 = BV(WGM01) | BV(CS02); /* Clear on Compare match & prescaler = 64 */ \
-                       TCNT0 = 0x00;                 /* initialization of Timer/Counter */ \
-                       OCR0 = OCR_DIVISOR;           /* Timer/Counter Output Compare Register */ \
-                       \
-                       /* Enable timer interrupts: Timer/Counter2 Output Compare (OCIE2) */ \
-                       TIMSK &= ~BV(TOIE0); \
-                       TIMSK |= BV(OCIE0); \
-                       \
-                       ENABLE_INTS; \
-               } while (0)
-
-#elif defined(CONFIG_TIMER_ON_TIMER1_OVERFLOW)
-
-#              define TIMER_INIT \
-               do { \
-                       DISABLE_INTS; \
-                       \
-                       /* Reset Timer overflow flag */ \
-                       TIFR |= BV(TOV1); \
-                       \
-                       /* Fast PWM mode, 24 kHz, no prescaling */ \
-                       TCCR1A |= BV(WGM11); \
-                       TCCR1A &= ~BV(WGM10); \
-                       TCCR1B |= BV(WGM12) | BV(CS10); \
-                       TCCR1B &= ~(BV(WGM13) | BV(CS11) | BV(CS12)); \
-                       \
-                       TCNT1 = 0x00;         /* initialization of Timer/Counter */ \
-                       \
-                       /* Enable timer interrupt: Timer/Counter1 Overflow */ \
-                       TIMSK |= BV(TOIE1); \
-                       \
-                       ENABLE_INTS; \
-               } while (0)
-
-#elif defined(CONFIG_TIMER_ON_TIMER2)
-
-#              define TIMER_INIT \
-               do { \
-                       DISABLE_INTS; \
-                       \
-                       /* Reset Timer flags */ \
-                       TIFR = BV(OCF2) | BV(TOV2); \
-                       \
-                       /* Setup Timer/Counter interrupt */ \
-                       TCCR2 = BV(WGM21) | BV(CS21) | BV(CS20); \
-                                             /* Clear on Compare match & prescaler = 64, internal sys clock */ \
-                       TCNT2 = 0x00;         /* initialization of Timer/Counter */ \
-                       OCR2 = OCR_DIVISOR;   /* Timer/Counter Output Compare Register */ \
-                       \
-                       /* Enable timer interrupts: Timer/Counter2 Output Compare (OCIE2) */ \
-                       TIMSK &= ~BV(TOIE2); \
-                       TIMSK |= BV(OCIE2); \
-                       \
-                       ENABLE_INTS; \
-               } while (0)
+/*
+ * Hardware dependent timer initialization.
+ */
+#if (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE0)
 
-#else
-#              error Choose witch timer to use with CONFIG_TIMER_ON_TIMERx
-#endif /* CONFIG_TIMER_ON_TIMERx */
+       #define TIMER_PRESCALER      64
+       #define TIMER_HW_BITS        8
+       #define DEFINE_TIMER_ISR     SIGNAL(SIG_OUTPUT_COMPARE0)
+       #define TIMER_TICKS_PER_SEC  1000
+       #define TIMER_HW_CNT         OCR_DIVISOR
 
+       /// Type of time expressed in ticks of the hardware high-precision timer
+       typedef uint8_t hptime_t;
 
-#if defined(CONFIG_TIMER_ON_TIMER1_OVERFLOW)
+#elif (CONFIG_TIMER == TIMER_ON_OVERFLOW1)
 
-       #define DEFINE_TIMER_ISR        \
-               static void timer_handler(void)
+       #define TIMER_PRESCALER      1
+       #define TIMER_HW_BITS        8
+       /** This value is the maximum in overflow based timers. */
+       #define TIMER_HW_CNT         (1 << TIMER_HW_BITS)
+       #define DEFINE_TIMER_ISR     SIGNAL(SIG_OVERFLOW1)
+       #define TIMER_TICKS_PER_SEC  ((TIMER_HW_HPTICKS_PER_SEC + TIMER_HW_CNT / 2) / TIMER_HW_CNT)
 
-       /*
-       * Timer 1 overflow irq handler.
-       */
-       SIGNAL(SIG_OVERFLOW1)
-       {
-               /*!
-               * How many overflow we have to count before calling the true timer handler.
-               * If timer overflow is at 24 kHz, with a value of 24 we have 1 ms between
-               * each call.
-               */
-       #define TIMER1_OVF_COUNT 24
+       /// Type of time expressed in ticks of the hardware high precision timer
+       typedef uint16_t hptime_t;
 
-               static uint8_t count = TIMER1_OVF_COUNT;
+#elif (CONFIG_TIMER == TIMER_ON_OUTPUT_COMPARE2)
 
-               count--;
-               if (!count)
-               {
-                       timer_handler();
-                       count = TIMER1_OVF_COUNT;
-               }
-       }
+       #define TIMER_PRESCALER      64
+       #define TIMER_HW_BITS        8
+       #if CPU_AVR_ATMEGA1281 || CPU_AVR_ATMEGA168
+               #define DEFINE_TIMER_ISR     SIGNAL(SIG_OUTPUT_COMPARE2A)
+       #else
+               #define DEFINE_TIMER_ISR     SIGNAL(SIG_OUTPUT_COMPARE2)
+       #endif
+       #define TIMER_TICKS_PER_SEC  1000
+       /** Value for OCR register in output-compare based timers. */
+       #define TIMER_HW_CNT         OCR_DIVISOR
 
-#elif defined (CONFIG_TIMER_ON_TIMER0)
 
-       #define DEFINE_TIMER_ISR        \
-               SIGNAL(SIG_OUTPUT_COMPARE0)
+       /// Type of time expressed in ticks of the hardware high precision timer
+       typedef uint8_t hptime_t;
 
-#elif defined(CONFIG_TIMER_ON_TIMER2)
+#elif (CONFIG_TIMER == TIMER_ON_OVERFLOW3)
 
-       #define DEFINE_TIMER_ISR        \
-               SIGNAL(SIG_OUTPUT_COMPARE2)
+       #define TIMER_PRESCALER      1
+       #define TIMER_HW_BITS        8
+       /** This value is the maximum in overflow based timers. */
+       #define TIMER_HW_CNT         (1 << TIMER_HW_BITS)
+       #define DEFINE_TIMER_ISR     SIGNAL(SIG_OVERFLOW3)
+       #define TIMER_TICKS_PER_SEC  ((TIMER_HW_HPTICKS_PER_SEC + TIMER_HW_CNT / 2) / TIMER_HW_CNT)
 
+       /// Type of time expressed in ticks of the hardware high precision timer
+       typedef uint16_t hptime_t;
 #else
-#      error Choose witch timer to use with CONFIG_TIMER_ON_TIMERx
-#endif /* CONFIG_TIMER_ON_TIMERx */
+
+       #error Unimplemented value for CONFIG_TIMER
+#endif /* CONFIG_TIMER */
+
+
+/** Frequency of the hardware high precision timer. */
+#define TIMER_HW_HPTICKS_PER_SEC  ((CLOCK_FREQ + TIMER_PRESCALER / 2) / TIMER_PRESCALER)
+
+/**
+ * System timer: additional division after the prescaler
+ * 12288000 / 64 / 192 (0..191) = 1 ms
+ */
+#define OCR_DIVISOR  (((CLOCK_FREQ + TIMER_PRESCALER / 2) / TIMER_PRESCALER + TIMER_TICKS_PER_SEC / 2) / TIMER_TICKS_PER_SEC - 1)
+
+/** Not needed, IRQ timer flag cleared automatically */
+#define timer_hw_irq() do {} while (0)
+
 
 #endif /* DRV_TIMER_AVR_H */