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path: root/os/hal/ports/NRF5/NRF51822/hal_pwm_lld.c
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Diffstat (limited to 'os/hal/ports/NRF5/NRF51822/hal_pwm_lld.c')
-rw-r--r--os/hal/ports/NRF5/NRF51822/hal_pwm_lld.c132
1 files changed, 92 insertions, 40 deletions
diff --git a/os/hal/ports/NRF5/NRF51822/hal_pwm_lld.c b/os/hal/ports/NRF5/NRF51822/hal_pwm_lld.c
index 378525f..f446fd3 100644
--- a/os/hal/ports/NRF5/NRF51822/hal_pwm_lld.c
+++ b/os/hal/ports/NRF5/NRF51822/hal_pwm_lld.c
@@ -30,6 +30,7 @@
/* Driver local definitions. */
/*===========================================================================*/
+#define PWM_GPIOTE_PPI_CC 3
/*===========================================================================*/
/* Driver exported variables. */
@@ -63,19 +64,23 @@ PWMDriver PWMD3;
/* Driver local variables and types. */
/*===========================================================================*/
+static const uint8_t pwm_margin_by_prescaler[] = {
+ 80, 40, 20, 15, 10, 5, 2, 1, 1, 1
+};
+
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
static void pwm_lld_serve_interrupt(PWMDriver *pwmp) {
- // Deal with PWM channels
- uint8_t n;
- for (n = 0 ; n < pwmp->channels ; n++) {
- if (pwmp->timer->EVENTS_COMPARE[n]) {
- pwmp->timer->EVENTS_COMPARE[n] = 0;
-
- if (pwmp->config->channels[n].callback != NULL) {
- pwmp->config->channels[n].callback(pwmp);
+ uint8_t channel;
+ // Deal with PWM channels
+ for (channel = 0 ; channel < pwmp->channels ; channel++) {
+ if (pwmp->timer->EVENTS_COMPARE[channel]) {
+ pwmp->timer->EVENTS_COMPARE[channel] = 0;
+
+ if (pwmp->config->channels[channel].callback != NULL) {
+ pwmp->config->channels[channel].callback(pwmp);
}
}
}
@@ -88,7 +93,14 @@ static void pwm_lld_serve_interrupt(PWMDriver *pwmp) {
pwmp->config->callback(pwmp);
}
}
+}
+static inline
+bool pwm_within_safe_margins(PWMDriver *pwmp, uint32_t timer, uint32_t width) {
+ const uint32_t margin = pwm_margin_by_prescaler[pwmp->timer->PRESCALER];
+ return (width <= margin)
+ ? ((width <= timer) && (timer < (pwmp->period + width - margin)))
+ : ((width <= timer) || (timer < (width - margin)));
}
/*===========================================================================*/
@@ -245,7 +257,7 @@ void pwm_lld_start(PWMDriver *pwmp) {
* @notapi
*/
void pwm_lld_stop(PWMDriver *pwmp) {
- pwmp->timer->TASKS_STOP = 1;
+ pwmp->timer->TASKS_SHUTDOWN = 1;
#if NRF5_PWM_USE_TIMER0
if (&PWMD1 == pwmp) {
@@ -284,41 +296,81 @@ void pwm_lld_enable_channel(PWMDriver *pwmp,
pwmcnt_t width) {
#if NRF5_PWM_USE_GPIOTE_PPI
const PWMChannelConfig *cfg_channel = &pwmp->config->channels[channel];
-
+ const uint8_t gpiote_channel = cfg_channel->gpiote_channel;
+ const uint8_t *ppi_channel = cfg_channel->ppi_channel;
+
uint32_t outinit;
switch(cfg_channel->mode & PWM_OUTPUT_MASK) {
- case PWM_OUTPUT_ACTIVE_LOW:
- outinit = GPIOTE_CONFIG_OUTINIT_Low;
- break;
- case PWM_OUTPUT_ACTIVE_HIGH:
- outinit = GPIOTE_CONFIG_OUTINIT_High;
- break;
- case PWM_OUTPUT_DISABLED:
- default:
- goto no_output_config;
+ case PWM_OUTPUT_ACTIVE_LOW : outinit = GPIOTE_CONFIG_OUTINIT_Low; break;
+ case PWM_OUTPUT_ACTIVE_HIGH: outinit = GPIOTE_CONFIG_OUTINIT_High; break;
+ case PWM_OUTPUT_DISABLED : /* fall-through */
+ default : goto no_output_config;
}
- const uint32_t gpio_pin = PAL_PAD(cfg_channel->ioline);
- const uint8_t gpiote_channel = cfg_channel->gpiote_channel;
- const uint8_t *ppi_channel = cfg_channel->ppi_channel;
- const uint32_t polarity = GPIOTE_CONFIG_POLARITY_Toggle;
-
- // Create GPIO Task
- NRF_GPIOTE->CONFIG[gpiote_channel] = GPIOTE_CONFIG_MODE_Task |
- ((gpio_pin << GPIOTE_CONFIG_PSEL_Pos ) & GPIOTE_CONFIG_PSEL_Msk) |
- ((polarity << GPIOTE_CONFIG_POLARITY_Pos) & GPIOTE_CONFIG_POLARITY_Msk) |
- ((outinit << GPIOTE_CONFIG_OUTINIT_Pos ) & GPIOTE_CONFIG_OUTINIT_Msk);
-
- // Program tasks (one for duty cycle, one for periode)
- NRF_PPI->CH[ppi_channel[0]].EEP =
- (uint32_t)&pwmp->timer->EVENTS_COMPARE[channel];
- NRF_PPI->CH[ppi_channel[0]].TEP =
- (uint32_t)&NRF_GPIOTE->TASKS_OUT[gpiote_channel];
- NRF_PPI->CH[ppi_channel[1]].EEP =
- (uint32_t)&pwmp->timer->EVENTS_COMPARE[pwmp->channels];
- NRF_PPI->CH[ppi_channel[1]].TEP =
- (uint32_t)&NRF_GPIOTE->TASKS_OUT[gpiote_channel];
- NRF_PPI->CHENSET = ((1 << ppi_channel[0]) | (1 << ppi_channel[1]));
+ // Deal with corner case: 0% and 100%
+ if ((width <= 0) || (width >= pwmp->period)) {
+ // Disable GPIOTE/PPI task
+ NRF_GPIOTE->CONFIG[gpiote_channel] = GPIOTE_CONFIG_MODE_Disabled;
+ NRF_PPI->CHENCLR = ((1 << ppi_channel[0]) | (1 << ppi_channel[1]));
+ // Set Line
+ palWriteLine(cfg_channel->ioline,
+ ((width <= 0) ^
+ ((cfg_channel->mode & PWM_OUTPUT_MASK) == PWM_OUTPUT_ACTIVE_HIGH)));
+
+ // Really doing PWM
+ } else {
+ const uint32_t gpio_pin = PAL_PAD(cfg_channel->ioline);
+ const uint32_t polarity = GPIOTE_CONFIG_POLARITY_Toggle;
+
+ // Program tasks (one for duty cycle, one for periode)
+ NRF_PPI->CH[ppi_channel[0]].EEP =
+ (uint32_t)&pwmp->timer->EVENTS_COMPARE[channel];
+ NRF_PPI->CH[ppi_channel[0]].TEP =
+ (uint32_t)&NRF_GPIOTE->TASKS_OUT[gpiote_channel];
+ NRF_PPI->CH[ppi_channel[1]].EEP =
+ (uint32_t)&pwmp->timer->EVENTS_COMPARE[pwmp->channels];
+ NRF_PPI->CH[ppi_channel[1]].TEP =
+ (uint32_t)&NRF_GPIOTE->TASKS_OUT[gpiote_channel];
+ NRF_PPI->CHENSET = ((1 << ppi_channel[0]) | (1 << ppi_channel[1]));
+
+ // Something Old, something New
+ const uint32_t old_width = pwmp->timer->CC[channel];
+ const uint32_t new_width = width;
+
+ // Check GPIOTE state
+ const bool gpiote = (NRF_GPIOTE->CONFIG[gpiote_channel] &
+ GPIOTE_CONFIG_MODE_Msk) != GPIOTE_CONFIG_MODE_Disabled;
+
+ // GPIOTE is currently running
+ if (gpiote) {
+ uint32_t current;
+ while (true) {
+ pwmp->timer->TASKS_CAPTURE[PWM_GPIOTE_PPI_CC] = 1;
+ current = pwmp->timer->CC[PWM_GPIOTE_PPI_CC];
+
+ if (pwm_within_safe_margins(pwmp, current, old_width) &&
+ pwm_within_safe_margins(pwmp, current, new_width))
+ break;
+ }
+ if (((old_width <= current) && (current < new_width)) ||
+ ((new_width <= current) && (current < old_width))) {
+ NRF_GPIOTE->TASKS_OUT[gpiote_channel] = 1;
+ }
+
+ // GPIOTE need to be restarted
+ } else {
+ // Create GPIO Task
+ NRF_GPIOTE->CONFIG[gpiote_channel] =
+ (GPIOTE_CONFIG_MODE_Task << GPIOTE_CONFIG_MODE_Pos) |
+ ((gpio_pin << GPIOTE_CONFIG_PSEL_Pos ) & GPIOTE_CONFIG_PSEL_Msk )|
+ ((polarity << GPIOTE_CONFIG_POLARITY_Pos) & GPIOTE_CONFIG_POLARITY_Msk)|
+ ((outinit << GPIOTE_CONFIG_OUTINIT_Pos ) & GPIOTE_CONFIG_OUTINIT_Msk );
+
+ pwmp->timer->TASKS_CAPTURE[PWM_GPIOTE_PPI_CC] = 1;
+ if (pwmp->timer->CC[PWM_GPIOTE_PPI_CC] > width)
+ NRF_GPIOTE->TASKS_OUT[gpiote_channel] = 1;
+ }
+ }
no_output_config:
#endif
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-08 16:38:30 +0000