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/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2017 Scott Shawcroft for Adafruit Industries
* Copyright (c) 2016 Damien P. George
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include <stdint.h>
#include "py/runtime.h"
#include "common-hal/pulseio/PWMOut.h"
#include "shared-bindings/pulseio/PWMOut.h"
#include "shared-bindings/microcontroller/Processor.h"
#include "timer_handler.h"
#include "atmel_start_pins.h"
#include "hal/utils/include/utils_repeat_macro.h"
#include "samd/timers.h"
#include "supervisor/shared/translate.h"
#include "samd/pins.h"
#undef ENABLE
# define _TCC_SIZE(unused, n) TCC ## n ## _SIZE,
# define TCC_SIZES { REPEAT_MACRO(_TCC_SIZE, 0, TCC_INST_NUM) }
static uint32_t tcc_periods[TCC_INST_NUM];
static uint32_t tc_periods[TC_INST_NUM];
uint32_t target_tcc_frequencies[TCC_INST_NUM];
uint8_t tcc_refcount[TCC_INST_NUM];
// This bitmask keeps track of which channels of a TCC are currently claimed.
#ifdef SAMD21
uint8_t tcc_channels[3]; // Set by pwmout_reset() to {0xf0, 0xfc, 0xfc} initially.
#endif
#ifdef SAMD51
uint8_t tcc_channels[5]; // Set by pwmout_reset() to {0xc0, 0xf0, 0xf8, 0xfc, 0xfc} initially.
#endif
static uint8_t never_reset_tc_or_tcc[TC_INST_NUM + TCC_INST_NUM];
STATIC void timer_refcount(int index, bool is_tc, int increment) {
if (is_tc) {
never_reset_tc_or_tcc[index] += increment;
} else {
never_reset_tc_or_tcc[TC_INST_NUM + index] += increment;
}
}
void timer_never_reset(int index, bool is_tc) {
timer_refcount(index, is_tc, 1);
}
void timer_reset_ok(int index, bool is_tc) {
timer_refcount(index, is_tc, -1);
}
void common_hal_pulseio_pwmout_never_reset(pulseio_pwmout_obj_t *self) {
timer_never_reset(self->timer->index, self->timer->is_tc);
never_reset_pin_number(self->pin->number);
}
void common_hal_pulseio_pwmout_reset_ok(pulseio_pwmout_obj_t *self) {
timer_reset_ok(self->timer->index, self->timer->is_tc);
}
void pwmout_reset(void) {
// Reset all timers
for (int i = 0; i < TCC_INST_NUM; i++) {
target_tcc_frequencies[i] = 0;
tcc_refcount[i] = 0;
}
Tcc *tccs[TCC_INST_NUM] = TCC_INSTS;
for (int i = 0; i < TCC_INST_NUM; i++) {
if (never_reset_tc_or_tcc[TC_INST_NUM + i] > 0) {
continue;
}
// Disable the module before resetting it.
if (tccs[i]->CTRLA.bit.ENABLE == 1) {
tccs[i]->CTRLA.bit.ENABLE = 0;
while (tccs[i]->SYNCBUSY.bit.ENABLE == 1) {
}
}
uint8_t mask = 0xff;
for (uint8_t j = 0; j < tcc_cc_num[i]; j++) {
mask <<= 1;
}
tcc_channels[i] = mask;
tccs[i]->CTRLA.bit.SWRST = 1;
while (tccs[i]->CTRLA.bit.SWRST == 1) {
}
}
Tc *tcs[TC_INST_NUM] = TC_INSTS;
for (int i = 0; i < TC_INST_NUM; i++) {
if (never_reset_tc_or_tcc[i] > 0) {
continue;
}
tcs[i]->COUNT16.CTRLA.bit.SWRST = 1;
while (tcs[i]->COUNT16.CTRLA.bit.SWRST == 1) {
}
}
}
static uint8_t tcc_channel(const pin_timer_t* t) {
// For the SAMD51 this hardcodes the use of OTMX == 0x0, the output matrix mapping, which uses
// SAMD21-style modulo mapping.
return t->wave_output % tcc_cc_num[t->index];
}
bool channel_ok(const pin_timer_t* t) {
uint8_t channel_bit = 1 << tcc_channel(t);
return (!t->is_tc && ((tcc_channels[t->index] & channel_bit) == 0)) ||
t->is_tc;
}
pwmout_result_t common_hal_pulseio_pwmout_construct(pulseio_pwmout_obj_t* self,
const mcu_pin_obj_t* pin,
uint16_t duty,
uint32_t frequency,
bool variable_frequency) {
self->pin = pin;
self->variable_frequency = variable_frequency;
self->duty_cycle = duty;
if (pin->timer[0].index >= TC_INST_NUM &&
pin->timer[1].index >= TCC_INST_NUM
#ifdef SAMD51
&& pin->timer[2].index >= TCC_INST_NUM
#endif
) {
return PWMOUT_INVALID_PIN;
}
if (frequency == 0 || frequency > 6000000) {
return PWMOUT_INVALID_FREQUENCY;
}
// Figure out which timer we are using.
// First see if a tcc is already going with the frequency we want and our
// channel is unused. tc's don't have enough channels to share.
const pin_timer_t* timer = NULL;
uint8_t mux_position = 0;
if (!variable_frequency) {
for (uint8_t i = 0; i < TCC_INST_NUM && timer == NULL; i++) {
if (target_tcc_frequencies[i] != frequency) {
continue;
}
for (uint8_t j = 0; j < NUM_TIMERS_PER_PIN && timer == NULL; j++) {
const pin_timer_t* t = &pin->timer[j];
if (t->index != i || t->is_tc || t->index >= TCC_INST_NUM) {
continue;
}
Tcc* tcc = tcc_insts[t->index];
if (tcc->CTRLA.bit.ENABLE == 1 && channel_ok(t)) {
timer = t;
mux_position = j;
// Claim channel.
tcc_channels[timer->index] |= (1 << tcc_channel(timer));
}
}
}
}
// No existing timer has been found, so find a new one to use and set it up.
if (timer == NULL) {
// By default, with fixed frequency we want to share a TCC because its likely we'll have
// other outputs at the same frequency. If the frequency is variable then we'll only have
// one output so we start with the TCs to see if they work.
int8_t direction = -1;
uint8_t start = NUM_TIMERS_PER_PIN - 1;
bool found = false;
if (variable_frequency) {
direction = 1;
start = 0;
}
for (int8_t i = start; i >= 0 && i < NUM_TIMERS_PER_PIN && timer == NULL; i += direction) {
const pin_timer_t* t = &pin->timer[i];
if ((!t->is_tc && t->index >= TCC_INST_NUM) ||
(t->is_tc && t->index >= TC_INST_NUM)) {
continue;
}
if (t->is_tc) {
found = true;
Tc* tc = tc_insts[t->index];
if (tc->COUNT16.CTRLA.bit.ENABLE == 0 && t->wave_output == 1) {
timer = t;
mux_position = i;
}
} else {
Tcc* tcc = tcc_insts[t->index];
if (tcc->CTRLA.bit.ENABLE == 0 && channel_ok(t)) {
timer = t;
mux_position = i;
}
}
}
if (timer == NULL) {
if (found) {
return PWMOUT_ALL_TIMERS_ON_PIN_IN_USE;
}
return PWMOUT_ALL_TIMERS_IN_USE;
}
uint8_t resolution = 0;
if (timer->is_tc) {
resolution = 16;
} else {
// TCC resolution varies so look it up.
const uint8_t _tcc_sizes[TCC_INST_NUM] = TCC_SIZES;
resolution = _tcc_sizes[timer->index];
}
// First determine the divisor that gets us the highest resolution.
uint32_t system_clock = common_hal_mcu_processor_get_frequency();
uint32_t top;
uint8_t divisor;
for (divisor = 0; divisor < 8; divisor++) {
top = (system_clock / prescaler[divisor] / frequency) - 1;
if (top < (1u << resolution)) {
break;
}
}
set_timer_handler(timer->is_tc, timer->index, TC_HANDLER_NO_INTERRUPT);
// We use the zeroeth clock on either port to go full speed.
turn_on_clocks(timer->is_tc, timer->index, 0);
if (timer->is_tc) {
tc_periods[timer->index] = top;
Tc* tc = tc_insts[timer->index];
#ifdef SAMD21
tc->COUNT16.CTRLA.reg = TC_CTRLA_MODE_COUNT16 |
TC_CTRLA_PRESCALER(divisor) |
TC_CTRLA_WAVEGEN_MPWM;
tc->COUNT16.CC[0].reg = top;
#endif
#ifdef SAMD51
tc->COUNT16.CTRLA.bit.SWRST = 1;
while (tc->COUNT16.CTRLA.bit.SWRST == 1) {
}
tc_set_enable(tc, false);
tc->COUNT16.CTRLA.reg = TC_CTRLA_MODE_COUNT16 | TC_CTRLA_PRESCALER(divisor);
tc->COUNT16.WAVE.reg = TC_WAVE_WAVEGEN_MPWM;
tc->COUNT16.CCBUF[0].reg = top;
tc->COUNT16.CCBUF[1].reg = 0;
#endif
tc_set_enable(tc, true);
} else {
tcc_periods[timer->index] = top;
Tcc* tcc = tcc_insts[timer->index];
tcc_set_enable(tcc, false);
tcc->CTRLA.bit.PRESCALER = divisor;
tcc->PER.bit.PER = top;
tcc->WAVE.bit.WAVEGEN = TCC_WAVE_WAVEGEN_NPWM_Val;
tcc_set_enable(tcc, true);
target_tcc_frequencies[timer->index] = frequency;
tcc_refcount[timer->index]++;
if (variable_frequency) {
// We're changing frequency so claim all of the channels.
tcc_channels[timer->index] = 0xff;
} else {
tcc_channels[timer->index] |= (1 << tcc_channel(timer));
}
}
}
self->timer = timer;
gpio_set_pin_function(pin->number, GPIO_PIN_FUNCTION_E + mux_position);
common_hal_pulseio_pwmout_set_duty_cycle(self, duty);
return PWMOUT_OK;
}
bool common_hal_pulseio_pwmout_deinited(pulseio_pwmout_obj_t* self) {
return self->pin == NULL;
}
void common_hal_pulseio_pwmout_deinit(pulseio_pwmout_obj_t* self) {
if (common_hal_pulseio_pwmout_deinited(self)) {
return;
}
const pin_timer_t* t = self->timer;
if (t->is_tc) {
Tc* tc = tc_insts[t->index];
tc_set_enable(tc, false);
tc->COUNT16.CTRLA.bit.SWRST = true;
tc_wait_for_sync(tc);
} else {
tcc_refcount[t->index]--;
tcc_channels[t->index] &= ~(1 << tcc_channel(t));
if (tcc_refcount[t->index] == 0) {
target_tcc_frequencies[t->index] = 0;
Tcc* tcc = tcc_insts[t->index];
tcc_set_enable(tcc, false);
tcc->CTRLA.bit.SWRST = true;
while (tcc->SYNCBUSY.bit.SWRST != 0) {
/* Wait for sync */
}
}
}
reset_pin_number(self->pin->number);
self->pin = NULL;
}
extern void common_hal_pulseio_pwmout_set_duty_cycle(pulseio_pwmout_obj_t* self, uint16_t duty) {
// Store the unadjusted duty cycle. It turns out the the process of adjusting and calculating
// the duty cycle here and reading it back is lossy - the value will decay over time.
// Track it here so that if frequency is changed we can use this value to recalculate the
// proper duty cycle.
// See https://github.com/adafruit/circuitpython/issues/2086 for more details
self->duty_cycle = duty;
const pin_timer_t* t = self->timer;
if (t->is_tc) {
uint16_t adjusted_duty = tc_periods[t->index] * duty / 0xffff;
#ifdef SAMD21
tc_insts[t->index]->COUNT16.CC[t->wave_output].reg = adjusted_duty;
#endif
#ifdef SAMD51
Tc* tc = tc_insts[t->index];
while (tc->COUNT16.SYNCBUSY.bit.CC1 != 0) {}
tc->COUNT16.CCBUF[1].reg = adjusted_duty;
#endif
} else {
uint32_t adjusted_duty = ((uint64_t) tcc_periods[t->index]) * duty / 0xffff;
uint8_t channel = tcc_channel(t);
Tcc* tcc = tcc_insts[t->index];
// Write into the CC buffer register, which will be transferred to the
// CC register on an UPDATE (when period is finished).
// Do clock domain syncing as necessary.
while (tcc->SYNCBUSY.reg != 0) {}
// Lock out double-buffering while updating the CCB value.
tcc->CTRLBSET.bit.LUPD = 1;
#ifdef SAMD21
tcc->CCB[channel].reg = adjusted_duty;
#endif
#ifdef SAMD51
tcc->CCBUF[channel].reg = adjusted_duty;
#endif
tcc->CTRLBCLR.bit.LUPD = 1;
}
}
uint16_t common_hal_pulseio_pwmout_get_duty_cycle(pulseio_pwmout_obj_t* self) {
const pin_timer_t* t = self->timer;
if (t->is_tc) {
Tc* tc = tc_insts[t->index];
tc_wait_for_sync(tc);
uint16_t cv = tc->COUNT16.CC[t->wave_output].reg;
return cv * 0xffff / tc_periods[t->index];
} else {
Tcc* tcc = tcc_insts[t->index];
uint8_t channel = tcc_channel(t);
uint32_t cv = 0;
while (tcc->SYNCBUSY.bit.CTRLB) {}
#ifdef SAMD21
// If CCBV (CCB valid) is set, the CCB value hasn't yet been copied
// to the CC value.
if ((tcc->STATUS.vec.CCBV & (1 << channel)) != 0) {
cv = tcc->CCB[channel].reg;
} else {
cv = tcc->CC[channel].reg;
}
#endif
#ifdef SAMD51
if ((tcc->STATUS.vec.CCBUFV & (1 << channel)) != 0) {
cv = tcc->CCBUF[channel].reg;
} else {
cv = tcc->CC[channel].reg;
}
#endif
uint32_t duty_cycle = ((uint64_t) cv) * 0xffff / tcc_periods[t->index];
return duty_cycle;
}
}
void common_hal_pulseio_pwmout_set_frequency(pulseio_pwmout_obj_t* self,
uint32_t frequency) {
if (frequency == 0 || frequency > 6000000) {
mp_raise_ValueError(translate("Invalid PWM frequency"));
}
const pin_timer_t* t = self->timer;
uint8_t resolution;
if (t->is_tc) {
resolution = 16;
} else {
resolution = 24;
}
uint32_t system_clock = common_hal_mcu_processor_get_frequency();
uint32_t new_top;
uint8_t new_divisor;
for (new_divisor = 0; new_divisor < 8; new_divisor++) {
new_top = (system_clock / prescaler[new_divisor] / frequency) - 1;
if (new_top < (1u << resolution)) {
break;
}
}
if (t->is_tc) {
Tc* tc = tc_insts[t->index];
uint8_t old_divisor = tc->COUNT16.CTRLA.bit.PRESCALER;
if (new_divisor != old_divisor) {
tc_set_enable(tc, false);
tc->COUNT16.CTRLA.bit.PRESCALER = new_divisor;
tc_set_enable(tc, true);
}
tc_periods[t->index] = new_top;
#ifdef SAMD21
tc->COUNT16.CC[0].reg = new_top;
#endif
#ifdef SAMD51
while (tc->COUNT16.SYNCBUSY.reg != 0) {}
tc->COUNT16.CCBUF[0].reg = new_top;
#endif
} else {
Tcc* tcc = tcc_insts[t->index];
uint8_t old_divisor = tcc->CTRLA.bit.PRESCALER;
if (new_divisor != old_divisor) {
tcc_set_enable(tcc, false);
tcc->CTRLA.bit.PRESCALER = new_divisor;
tcc_set_enable(tcc, true);
}
while (tcc->SYNCBUSY.reg != 0) {}
tcc_periods[t->index] = new_top;
#ifdef SAMD21
tcc->PERB.bit.PERB = new_top;
#endif
#ifdef SAMD51
tcc->PERBUF.bit.PERBUF = new_top;
#endif
}
common_hal_pulseio_pwmout_set_duty_cycle(self, self->duty_cycle);
}
uint32_t common_hal_pulseio_pwmout_get_frequency(pulseio_pwmout_obj_t* self) {
uint32_t system_clock = common_hal_mcu_processor_get_frequency();
const pin_timer_t* t = self->timer;
uint8_t divisor;
uint32_t top;
if (t->is_tc) {
divisor = tc_insts[t->index]->COUNT16.CTRLA.bit.PRESCALER;
top = tc_periods[t->index];
} else {
divisor = tcc_insts[t->index]->CTRLA.bit.PRESCALER;
top = tcc_periods[t->index];
}
return (system_clock / prescaler[divisor]) / (top + 1);
}
bool common_hal_pulseio_pwmout_get_variable_frequency(pulseio_pwmout_obj_t* self) {
return self->variable_frequency;
}