circuitpython/ports/nrf/mphalport.c

375 lines
11 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2015 Glenn Ruben Bakke
*
* 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 <string.h>
#include "py/mpstate.h"
#include "py/mphal.h"
#include "py/mperrno.h"
#include "py/runtime.h"
#include "py/stream.h"
#include "uart.h"
#include "nrfx_errors.h"
#include "nrfx_config.h"
#if MICROPY_PY_TIME_TICKS
#include "nrfx_rtc.h"
#include "nrf_clock.h"
#endif
#if MICROPY_PY_TIME_TICKS
// Use RTC1 for time ticks generation (ms and us) with 32kHz tick resolution
// and overflow handling in RTC IRQ.
#define RTC_TICK_INCREASE_MSEC (33)
#define RTC_RESCHEDULE_CC(rtc, cc_nr, ticks) \
do { \
nrfx_rtc_cc_set(&rtc, cc_nr, nrfx_rtc_counter_get(&rtc) + ticks, true); \
} while (0);
// RTC overflow irq handling notes:
// - If has_overflowed is set it could be before or after COUNTER is read.
// If before then an adjustment must be made, if after then no adjustment is necessary.
// - The before case is when COUNTER is very small (because it just overflowed and was set to zero),
// the after case is when COUNTER is very large (because it's just about to overflow
// but we read it right before it overflows).
// - The extra check for counter is to distinguish these cases. 1<<23 because it's halfway
// between min and max values of COUNTER.
#define RTC1_GET_TICKS_ATOMIC(rtc, overflows, counter) \
do { \
rtc.p_reg->INTENCLR = RTC_INTENCLR_OVRFLW_Msk; \
overflows = rtc_overflows; \
counter = rtc.p_reg->COUNTER; \
uint32_t has_overflowed = rtc.p_reg->EVENTS_OVRFLW; \
if (has_overflowed && counter < (1 << 23)) { \
overflows += 1; \
} \
rtc.p_reg->INTENSET = RTC_INTENSET_OVRFLW_Msk; \
} while (0);
nrfx_rtc_t rtc1 = NRFX_RTC_INSTANCE(1);
volatile mp_uint_t rtc_overflows = 0;
const nrfx_rtc_config_t rtc_config_time_ticks = {
.prescaler = 0,
.reliable = 0,
.tick_latency = 0,
#ifdef NRF51
.interrupt_priority = 1,
#else
.interrupt_priority = 3,
#endif
};
STATIC void rtc_irq_time(nrfx_rtc_int_type_t event) {
// irq handler for overflow
if (event == NRFX_RTC_INT_OVERFLOW) {
rtc_overflows += 1;
}
// irq handler for wakeup from WFI (~1msec)
if (event == NRFX_RTC_INT_COMPARE0) {
RTC_RESCHEDULE_CC(rtc1, 0, RTC_TICK_INCREASE_MSEC)
}
}
void rtc1_init_time_ticks(void) {
// Start the low-frequency clock (if it hasn't been started already)
if (!nrf_clock_lf_is_running(NRF_CLOCK)) {
nrf_clock_task_trigger(NRF_CLOCK, NRF_CLOCK_TASK_LFCLKSTART);
}
// Uninitialize first, then set overflow IRQ and first CC event
nrfx_rtc_uninit(&rtc1);
nrfx_rtc_init(&rtc1, &rtc_config_time_ticks, rtc_irq_time);
nrfx_rtc_overflow_enable(&rtc1, true);
RTC_RESCHEDULE_CC(rtc1, 0, RTC_TICK_INCREASE_MSEC)
nrfx_rtc_enable(&rtc1);
}
mp_uint_t mp_hal_ticks_ms(void) {
// Compute: (rtc_overflows << 24 + COUNTER) * 1000 / 32768
//
// Note that COUNTER * 1000 / 32768 would overflow during calculation, so use
// the less obvious * 125 / 4096 calculation (overflow secure).
//
// Make sure not to call this function within an irq with higher prio than the
// RTC's irq. This would introduce the danger of preempting the RTC irq and
// calling mp_hal_ticks_ms() at that time would return a false result.
uint32_t overflows;
uint32_t counter;
// guard against overflow irq
RTC1_GET_TICKS_ATOMIC(rtc1, overflows, counter)
return (overflows << 9) * 1000 + (counter * 125 / 4096);
}
mp_uint_t mp_hal_ticks_us(void) {
// Compute: ticks_us = (overflows << 24 + counter) * 1000000 / 32768
// = (overflows << 15 * 15625) + (counter * 15625 / 512)
// Since this function is likely to be called in a poll loop it must
// be fast, using an optimized 64bit mult/divide.
uint32_t overflows;
uint32_t counter;
// guard against overflow irq
RTC1_GET_TICKS_ATOMIC(rtc1, overflows, counter)
// first compute counter * 15625
uint32_t counter_lo = (counter & 0xffff) * 15625;
uint32_t counter_hi = (counter >> 16) * 15625;
// actual value is counter_hi << 16 + counter_lo
return ((overflows << 15) * 15625) + ((counter_hi << 7) + (counter_lo >> 9));
}
#else
mp_uint_t mp_hal_ticks_ms(void) {
return 0;
}
#endif
// this table converts from HAL_StatusTypeDef to POSIX errno
const byte mp_hal_status_to_errno_table[4] = {
[HAL_OK] = 0,
[HAL_ERROR] = MP_EIO,
[HAL_BUSY] = MP_EBUSY,
[HAL_TIMEOUT] = MP_ETIMEDOUT,
};
NORETURN void mp_hal_raise(HAL_StatusTypeDef status) {
mp_raise_OSError(mp_hal_status_to_errno_table[status]);
}
#if !MICROPY_KBD_EXCEPTION
void mp_hal_set_interrupt_char(int c) {
}
#endif
#if !MICROPY_PY_BLE_NUS
uintptr_t mp_hal_stdio_poll(uintptr_t poll_flags) {
uintptr_t ret = 0;
if ((poll_flags & MP_STREAM_POLL_RD) && MP_STATE_PORT(board_stdio_uart) != NULL
&& uart_rx_any(MP_STATE_PORT(board_stdio_uart))) {
ret |= MP_STREAM_POLL_RD;
}
return ret;
}
#endif
#if !MICROPY_PY_BLE_NUS && !MICROPY_HW_USB_CDC
int mp_hal_stdin_rx_chr(void) {
for (;;) {
if (MP_STATE_PORT(board_stdio_uart) != NULL && uart_rx_any(MP_STATE_PORT(board_stdio_uart))) {
return uart_rx_char(MP_STATE_PORT(board_stdio_uart));
}
MICROPY_EVENT_POLL_HOOK
}
return 0;
}
void mp_hal_stdout_tx_strn(const char *str, mp_uint_t len) {
if (MP_STATE_PORT(board_stdio_uart) != NULL) {
uart_tx_strn(MP_STATE_PORT(board_stdio_uart), str, len);
}
}
void mp_hal_stdout_tx_strn_cooked(const char *str, mp_uint_t len) {
if (MP_STATE_PORT(board_stdio_uart) != NULL) {
uart_tx_strn_cooked(MP_STATE_PORT(board_stdio_uart), str, len);
}
}
#endif
void mp_hal_stdout_tx_str(const char *str) {
mp_hal_stdout_tx_strn(str, strlen(str));
}
#if MICROPY_PY_TIME_TICKS
void mp_hal_delay_us(mp_uint_t us) {
uint32_t now;
if (us == 0) {
return;
}
now = mp_hal_ticks_us();
while (mp_hal_ticks_us() - now < us) {
}
}
void mp_hal_delay_ms(mp_uint_t ms) {
uint32_t now;
if (ms == 0) {
return;
}
now = mp_hal_ticks_ms();
while (mp_hal_ticks_ms() - now < ms) {
MICROPY_EVENT_POLL_HOOK
}
}
#else
void mp_hal_delay_us(mp_uint_t us) {
if (us == 0) {
return;
}
register uint32_t delay __ASM("r0") = us;
__ASM volatile (
"1:\n"
#ifdef NRF51
" SUB %0, %0, #1\n"
#else
" SUBS %0, %0, #1\n"
#endif
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
#if defined(NRF52) || defined(NRF9160_XXAA)
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
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" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
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" NOP\n"
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" NOP\n"
" NOP\n"
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" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
" NOP\n"
#endif
" BNE 1b\n"
: "+r" (delay));
}
void mp_hal_delay_ms(mp_uint_t ms) {
for (mp_uint_t i = 0; i < ms; i++)
{
mp_hal_delay_us(999);
}
}
#endif
#if defined(NRFX_LOG_ENABLED) && (NRFX_LOG_ENABLED == 1)
static const char nrfx_error_unknown[1] = "";
static const char nrfx_error_success[] = "NRFX_SUCCESS";
static const char nrfx_error_internal[] = "NRFX_ERROR_INTERNAL";
static const char nrfx_error_no_mem[] = "NRFX_ERROR_NO_MEM";
static const char nrfx_error_not_supported[] = "NRFX_ERROR_NOT_SUPPORTED";
static const char nrfx_error_invalid_param[] = "NRFX_ERROR_INVALID_PARAM";
static const char nrfx_error_invalid_state[] = "NRFX_ERROR_INVALID_STATE";
static const char nrfx_error_invalid_length[] = "NRFX_ERROR_INVALID_LENGTH";
static const char nrfx_error_timeout[] = "NRFX_ERROR_TIMEOUT";
static const char nrfx_error_forbidden[] = "NRFX_ERROR_FORBIDDEN";
static const char nrfx_error_null[] = "NRFX_ERROR_NULL";
static const char nrfx_error_invalid_addr[] = "NRFX_ERROR_INVALID_ADDR";
static const char nrfx_error_busy[] = "NRFX_ERROR_BUSY";
static const char nrfx_error_already_initalized[] = "NRFX_ERROR_ALREADY_INITIALIZED";
static const char *nrfx_error_strings[13] = {
nrfx_error_success,
nrfx_error_internal,
nrfx_error_no_mem,
nrfx_error_not_supported,
nrfx_error_invalid_param,
nrfx_error_invalid_state,
nrfx_error_invalid_length,
nrfx_error_timeout,
nrfx_error_forbidden,
nrfx_error_null,
nrfx_error_invalid_addr,
nrfx_error_busy,
nrfx_error_already_initalized
};
static const char nrfx_drv_error_twi_err_overrun[] = "NRFX_ERROR_DRV_TWI_ERR_OVERRUN";
static const char nrfx_drv_error_twi_err_anack[] = "NRFX_ERROR_DRV_TWI_ERR_ANACK";
static const char nrfx_drv_error_twi_err_dnack[] = "NRFX_ERROR_DRV_TWI_ERR_DNACK";
static const char *nrfx_drv_error_strings[3] = {
nrfx_drv_error_twi_err_overrun,
nrfx_drv_error_twi_err_anack,
nrfx_drv_error_twi_err_dnack
};
const char *nrfx_error_code_lookup(uint32_t err_code) {
if (err_code >= NRFX_ERROR_BASE_NUM && err_code <= NRFX_ERROR_BASE_NUM + 13) {
return nrfx_error_strings[err_code - NRFX_ERROR_BASE_NUM];
} else if (err_code >= NRFX_ERROR_DRIVERS_BASE_NUM && err_code <= NRFX_ERROR_DRIVERS_BASE_NUM + 3) {
return nrfx_drv_error_strings[err_code - NRFX_ERROR_DRIVERS_BASE_NUM];
}
return nrfx_error_unknown;
}
#endif // NRFX_LOG_ENABLED