+/**
+ * \file
+ * <!--
+ * This file is part of BeRTOS.
+ *
+ * Bertos is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction. Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License. This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ *
+ * Copyright 2008 Develer S.r.l. (http://www.develer.com/)
+ * All Rights Reserved.
+ * -->
+ *
+ * \brief Stepper driver interface implementation.
+ *
+ * This module use the three timer on the at91 family, to generate a
+ * six periodic variable pwm waveform. The pulse width is fix, and could
+ * change by setting the STEPPER_DELAY_ON_COMPARE_C define, but you make
+ * an attention to do this, becouse the pulse width is not exactly
+ * STEPPER_DELAY_ON_COMPARE_C. The pulse width depend also to latency
+ * time of cpu to serve an interrupt, this generate an pwm waveform affect
+ * to noise. This noise not effect the period but only the pulse width,
+ * becouse the raising edge is generate by hardware comply with the our
+ * period settings.
+ *
+ * Note: is most important to set STEPPER_DELAY_ON_COMPARE_C value minor
+ * than a interrupt time service, becouse the falling edge must be happen
+ * inside to inerrupt service to guarantee a correct functionaly of pwm
+ * generator.
+ *
+ *
+ * \version $Id$
+ *
+ * \author Daniele Basile <asterix@develer.com>
+ */
+
+#include "stepper_at91.h"
+
+#include <cfg/macros.h>
+#include <cfg/debug.h>
+
+#include <cpu/types.h>
+#include <cpu/irq.h>
+
+#include <io/arm.h>
+
+#include "appconfig.h"
+
+/*
+ * Delay to set C compare to clear output
+ * on select TIO output
+ */
+#define STEPPER_DELAY_ON_COMPARE_C 20
+
+/*
+ * Forward declaration for interrupt handler
+ */
+static void stepper_tc0_irq(void);
+static void stepper_tc1_irq(void);
+static void stepper_tc2_irq(void);
+
+///< Static array of timer counter struct for stepper.
+static struct TimerCounter stepper_timers[CONFIG_TC_STEPPER_MAX_NUM] =
+{
+ { //Timer Counter settings for TIOA0 output pin
+ .timer_id = TC0_ID,
+ .blk_ctrl_set = TC_NONEXC0,
+ .chl_mode_reg = &TC0_CMR,
+ .chl_ctrl_reg = &TC0_CCR,
+ .comp_effect_mask = TC_ACPA_MASK,
+ .comp_effect_set = TC_ACPA_SET_OUTPUT,
+ .comp_effect_clear = TC_ACPA_CLEAR_OUTPUT,
+ .comp_effect_c_mask = TC_ACPC_MASK,
+ .comp_effect_c_clear = TC_ACPC_CLEAR_OUTPUT,
+ .ext_event_set = TC_EEVT_XC0,
+ .comp_reg = &TC0_RA,
+ .comp_c_reg = &TC0_RC,
+ .count_val_reg = &TC0_CV,
+ .irq_enable_reg = &TC0_IER,
+ .irq_disable_reg = &TC0_IDR,
+ .irq_set_mask = BV(TC_CPAS),
+ .irq_mask_reg = &TC0_IMR,
+ .isr = stepper_tc0_irq,
+ .status_reg = &TC0_SR,
+ .tio_pin = TIOA0,
+ .callback = NULL,
+ .motor = NULL,
+ },
+ { //Timer Counter settings for TIOB0 output pin
+ .timer_id = TC0_ID,
+ .blk_ctrl_set = TC_NONEXC0,
+ .chl_mode_reg = &TC0_CMR,
+ .chl_ctrl_reg = &TC0_CCR,
+ .comp_reg = &TC0_RB,
+ .comp_c_reg = &TC0_RC,
+ .count_val_reg = &TC0_CV,
+ .comp_effect_mask = TC_BCPB_MASK,
+ .comp_effect_set = TC_BCPB_SET_OUTPUT,
+ .comp_effect_clear = TC_BCPB_CLEAR_OUTPUT,
+ .comp_effect_c_mask = TC_BCPC_MASK,
+ .comp_effect_c_clear = TC_BCPC_CLEAR_OUTPUT,
+ .ext_event_set = TC_EEVT_XC0,
+ .irq_enable_reg = &TC0_IER,
+ .irq_disable_reg = &TC0_IDR,
+ .irq_set_mask = BV(TC_CPBS),
+ .irq_mask_reg = &TC0_IMR,
+ .isr = stepper_tc0_irq,
+ .status_reg = &TC0_SR,
+ .tio_pin = TIOB0,
+ .callback = NULL,
+ .motor = NULL,
+ },
+ { //Timer Counter settings for TIOA1 output pin
+ .timer_id = TC1_ID,
+ .blk_ctrl_set = TC_NONEXC1,
+ .chl_mode_reg = &TC1_CMR,
+ .chl_ctrl_reg = &TC1_CCR,
+ .comp_reg = &TC1_RA,
+ .comp_c_reg = &TC1_RC,
+ .count_val_reg = &TC1_CV,
+ .comp_effect_mask = TC_ACPA_MASK,
+ .comp_effect_set = TC_ACPA_SET_OUTPUT,
+ .comp_effect_clear = TC_ACPA_CLEAR_OUTPUT,
+ .comp_effect_c_mask = TC_ACPC_MASK,
+ .comp_effect_c_clear = TC_ACPC_CLEAR_OUTPUT,
+ .ext_event_set = TC_EEVT_XC1,
+ .irq_enable_reg = &TC1_IER,
+ .irq_disable_reg = &TC1_IDR,
+ .irq_set_mask = BV(TC_CPAS),
+ .irq_mask_reg = &TC1_IMR,
+ .isr = stepper_tc1_irq,
+ .status_reg = &TC1_SR,
+ .tio_pin = TIOA1,
+ .callback = NULL,
+ .motor = NULL,
+ },
+ { //Timer Counter settings for TIOB1 output pin
+ .timer_id = TC1_ID,
+ .blk_ctrl_set = TC_NONEXC1,
+ .chl_mode_reg = &TC1_CMR,
+ .chl_ctrl_reg = &TC1_CCR,
+ .comp_reg = &TC1_RB,
+ .comp_c_reg = &TC1_RC,
+ .count_val_reg = &TC1_CV,
+ .comp_effect_mask = TC_BCPB_MASK,
+ .comp_effect_set = TC_BCPB_SET_OUTPUT,
+ .comp_effect_clear = TC_BCPB_CLEAR_OUTPUT,
+ .comp_effect_c_mask = TC_BCPC_MASK,
+ .comp_effect_c_clear = TC_BCPC_CLEAR_OUTPUT,
+ .ext_event_set = TC_EEVT_XC1,
+ .irq_enable_reg = &TC1_IER,
+ .irq_disable_reg = &TC1_IDR,
+ .irq_set_mask = BV(TC_CPBS),
+ .irq_mask_reg = &TC1_IMR,
+ .isr = stepper_tc1_irq,
+ .status_reg = &TC1_SR,
+ .tio_pin = TIOB1,
+ .callback = NULL,
+ .motor = NULL,
+ },
+ { //Timer Counter settings for TIOA2 output pin
+ .timer_id = TC2_ID,
+ .blk_ctrl_set = TC_NONEXC2,
+ .chl_mode_reg = &TC2_CMR,
+ .chl_ctrl_reg = &TC2_CCR,
+ .comp_reg = &TC2_RA,
+ .comp_c_reg = &TC2_RC,
+ .count_val_reg = &TC2_CV,
+ .comp_effect_mask = TC_ACPA_MASK,
+ .comp_effect_set = TC_ACPA_SET_OUTPUT,
+ .comp_effect_clear = TC_ACPA_CLEAR_OUTPUT,
+ .comp_effect_c_mask = TC_ACPC_MASK,
+ .comp_effect_c_clear = TC_ACPC_CLEAR_OUTPUT,
+ .ext_event_set = TC_EEVT_XC2,
+ .irq_enable_reg = &TC2_IER,
+ .irq_disable_reg = &TC2_IDR,
+ .irq_set_mask = BV(TC_CPAS),
+ .irq_mask_reg = &TC2_IMR,
+ .isr = stepper_tc2_irq,
+ .status_reg = &TC2_SR,
+ .tio_pin = TIOA2,
+ .callback = NULL,
+ .motor = NULL,
+ },
+ { //Timer Counter settings for TIOB2 output pin
+ .timer_id = TC2_ID,
+ .blk_ctrl_set = TC_NONEXC2,
+ .chl_mode_reg = &TC2_CMR,
+ .chl_ctrl_reg = &TC2_CCR,
+ .comp_reg = &TC2_RB,
+ .comp_c_reg = &TC2_RC,
+ .count_val_reg = &TC2_CV,
+ .comp_effect_mask = TC_BCPB_MASK,
+ .comp_effect_set = TC_BCPB_SET_OUTPUT,
+ .comp_effect_clear = TC_BCPB_CLEAR_OUTPUT,
+ .comp_effect_c_mask = TC_BCPC_MASK,
+ .comp_effect_c_clear = TC_BCPC_CLEAR_OUTPUT,
+ .ext_event_set = TC_EEVT_XC2,
+ .irq_enable_reg = &TC2_IER,
+ .irq_disable_reg = &TC2_IDR,
+ .irq_set_mask = BV(TC_CPBS),
+ .irq_mask_reg = &TC2_IMR,
+ .isr = stepper_tc2_irq,
+ .status_reg = &TC2_SR,
+ .tio_pin = TIOB2,
+ .callback = NULL,
+ .motor = NULL,
+ }
+};
+
+/**
+ * Generic TIO interrupt handler.
+ */
+INLINE void stepper_tc_tio_irq(struct TimerCounter * t)
+{
+ //
+ *t->chl_mode_reg &= ~t->comp_effect_c_mask;
+ *t->chl_mode_reg |= t->comp_effect_c_clear;
+
+ /*
+ * Cleat TIO output on c register compare.
+ * This generate an pulse with variable lenght, this
+ * depend to delay that interrupt is realy service.
+ */
+ *t->comp_c_reg = *t->count_val_reg + STEPPER_DELAY_ON_COMPARE_C;
+
+ //Call the associate callback
+ t->callback(t->motor);
+
+ *t->chl_mode_reg &= ~t->comp_effect_c_mask;
+}
+
+
+/*
+ * Interrupt handler for timer counter TCKL0
+ */
+static void ISR_FUNC stepper_tc0_irq(void)
+{
+ /*
+ * Warning: when we read the status_reg register, we reset it.
+ * That mean if is occur an interrupt event we can read only
+ * the last that has been occur. To not miss an interrupt event
+ * we save the status_reg register and then we read it.
+ */
+ uint32_t status_reg = TC0_SR & TC0_IMR;
+
+ if ((status_reg & BV(TC_CPBS)) && (status_reg & BV(TC_CPAS)))
+ STEPPER_STROBE_ON;
+
+ if (status_reg & BV(TC_CPAS))
+ stepper_tc_tio_irq(&stepper_timers[TC_TIOA0]);
+
+ if (status_reg & BV(TC_CPBS))
+ stepper_tc_tio_irq(&stepper_timers[TC_TIOB0]);
+
+ STEPPER_STROBE_OFF;
+ /* Inform hw that we have served the IRQ */
+ AIC_EOICR = 0;
+
+}
+
+/*
+ * Interrupt handler for timer counter TCKL1
+ */
+static void ISR_FUNC stepper_tc1_irq(void)
+{
+ STEPPER_STROBE_ON_1;
+ /*
+ * Warning: when we read the status_reg register, we reset it.
+ * That mean if is occur an interrupt event we can read only
+ * the last that has been occur. To not miss an interrupt event
+ * we save the status_reg register and then we read it.
+ */
+ uint32_t status_reg = TC1_SR & TC1_IMR;
+
+ if (status_reg & BV(TC_CPAS))
+ stepper_tc_tio_irq(&stepper_timers[TC_TIOA1]);
+
+ if (status_reg & BV(TC_CPBS))
+ stepper_tc_tio_irq(&stepper_timers[TC_TIOB1]);
+
+
+ /* Inform hw that we have served the IRQ */
+ AIC_EOICR = 0;
+ STEPPER_STROBE_OFF_1;
+}
+
+
+/*
+ * Interrupt handler for timer counter TCKL2
+ */
+static void ISR_FUNC stepper_tc2_irq(void)
+{
+
+ /*
+ * Warning: when we read the status_reg register, we reset it.
+ * That mean if is occur an interrupt event we can read only
+ * the last that has been occur. To not miss an interrupt event
+ * we save the status_reg register and then we read it.
+ */
+ uint32_t status_reg = TC2_SR & TC2_IMR;
+
+ STEPPER_STROBE_ON_2;
+ if (status_reg & BV(TC_CPAS))
+ stepper_tc_tio_irq(&stepper_timers[TC_TIOA2]);
+
+ if (status_reg & BV(TC_CPBS))
+ stepper_tc_tio_irq(&stepper_timers[TC_TIOB2]);
+
+ STEPPER_STROBE_OFF_2;
+ /* Inform hw that we have served the IRQ */
+ AIC_EOICR = 0;
+
+}
+
+/**
+ * Timer couter setup.
+ *
+ * This function apply to select timer couter all needed settings.
+ * Every settings are stored in stepper_timers[].
+ */
+void stepper_tc_setup(int index, stepper_isr_t callback, struct Stepper *motor)
+{
+ ASSERT(index < CONFIG_TC_STEPPER_MAX_NUM);
+
+ motor->timer = &stepper_timers[index];
+
+ //Disable PIO controller and enable TIO function
+ TIO_PIO_PDR = BV(motor->timer->tio_pin);
+ TIO_PIO_ABSR = BV(motor->timer->tio_pin);
+
+ /*
+ * Sets timer counter in waveform mode.
+ * We set as default:
+ * - Waveform mode 00 (see datasheet for more detail.)
+ * - Master clock prescaler to STEPPER_MCK_PRESCALER
+ * - Set none external event
+ * - Clear pin output on comp_reg
+ * - None effect on reg C compare
+ */
+ *motor->timer->chl_mode_reg = BV(TC_WAVE);
+ *motor->timer->chl_mode_reg |= motor->timer->ext_event_set;
+ *motor->timer->chl_mode_reg &= ~TC_WAVSEL_MASK;
+ *motor->timer->chl_mode_reg |= TC_WAVSEL_UP;
+ *motor->timer->chl_mode_reg |= STEPPER_MCK_PRESCALER;
+ *motor->timer->chl_mode_reg |= motor->timer->comp_effect_clear;
+ *motor->timer->chl_mode_reg &= ~motor->timer->comp_effect_c_mask;
+
+ //Reset comp_reg and C compare register
+ *motor->timer->comp_reg = 0;
+ *motor->timer->comp_c_reg = 0;
+
+ //Register interrupt vector
+ cpuflags_t flags;
+ IRQ_SAVE_DISABLE(flags);
+
+ /*
+ * Warning: To guarantee a correct management of interrupt event, we must
+ * trig the interrupt on level sensitive. This becouse, we have only a common
+ * line for interrupt request, and if we have at the same time two interrupt
+ * request could be that the is service normaly but the second will never
+ * been detected and interrupt will stay active but never serviced.
+ */
+ AIC_SVR(motor->timer->timer_id) = motor->timer->isr;
+ AIC_SMR(motor->timer->timer_id) = AIC_SRCTYPE_INT_LEVEL_SENSITIVE;
+ AIC_IECR = BV(motor->timer->timer_id);
+
+ // Disable interrupt on select timer counter
+ stepper_tc_irq_disable(motor->timer);
+
+ IRQ_RESTORE(flags);
+
+ //Register callback
+ motor->timer->callback = callback;
+ motor->timer->motor = motor;
+}
+
+/**
+ * Timer counter init.
+ */
+void stepper_tc_init(void)
+{
+ STEPPER_STROBE_INIT;
+
+ ASSERT(CONFIG_NUM_STEPPER_MOTORS <= CONFIG_TC_STEPPER_MAX_NUM);
+
+ /*
+ * Enable timer counter:
+ * - power on all timer counter
+ * - disable all interrupt
+ * - disable all external event/timer source
+ */
+ for (int i = 0; i < CONFIG_TC_STEPPER_MAX_NUM; i++)
+ {
+ PMC_PCER = BV(stepper_timers[i].timer_id);
+ *stepper_timers[i].irq_disable_reg = 0xFFFFFFFF;
+ TC_BMR = stepper_timers[i].blk_ctrl_set;
+ }
+
+ /*
+ * Enable timer counter and start it.
+ */
+ for (int i = 0; i < CONFIG_TC_STEPPER_MAX_NUM; i++)
+ *stepper_timers[i].chl_ctrl_reg = (BV(TC_CLKEN) | BV(TC_SWTRG));
+
+}
+