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earlephilhowerearlephilhower
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Support Bluetooth under FreeRTOS (#3095)
Integrate the BTStack run loop into the new LWIP work thread for CYW43 processing. Remove the async_context and use alarms and FreeRTOS primitves to do the work. FreeRTOS binary semaphores are a better way of not wasting time or burning CPU when waiting for the BTStack run loop to complete.
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‎cores/rp2040/cyw43_wrappers.cpp

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@@ -159,11 +159,19 @@ extern "C" void init_cyw43_wifi() {
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}
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extern "C" void __lockBluetooth() {
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#ifdef __FREERTOS
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cyw43_thread_enter();
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#else
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async_context_acquire_lock_blocking(cyw43_arch_async_context());
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#endif
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}
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extern "C" void __unlockBluetooth() {
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#ifdef __FREERTOS
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cyw43_thread_exit();
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#else
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async_context_release_lock(cyw43_arch_async_context());
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#endif
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}
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extern "C" void __pinMode(pin_size_t pin, PinMode mode);

‎cores/rp2040/lwip_wrap.cpp

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@@ -31,6 +31,7 @@
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#include <sys/lock.h>
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#include "_xoshiro.h"
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#include "lwip_wrap.h"
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#include <pico/btstack_run_loop_async_context.h>
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//auto_init_recursive_mutex(__lwipMutex); // Only for case with no Ethernet or PicoW, but still doing LWIP (PPP?)
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recursive_mutex_t __lwipMutex;
@@ -900,6 +901,11 @@ extern "C" {
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__real_cyw43_arch_gpio_put(wl_gpio, value);
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}
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extern const btstack_run_loop_t *__real_btstack_run_loop_async_context_get_instance(async_context_t *async_context);
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const btstack_run_loop_t *__wrap_btstack_run_loop_async_context_get_instance(async_context_t *async_context) {
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return __real_btstack_run_loop_async_context_get_instance(async_context);
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}
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#endif
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‎cores/rp2040/sdkoverride/btstack_run_loop_async_context.cpp

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@@ -0,0 +1,158 @@
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// Hacked by EFP3 to with FreeRTOS native, no async context.
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#ifdef __FREERTOS
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/*
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Copyright (c) 2023 Raspberry Pi (Trading) Ltd.
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SPDX-License-Identifier: BSD-3-Clause
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*/
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#include <Arduino.h>
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#include <lwip_wrap.h>
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#include "FreeRTOS.h"
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#include "semphr.h"
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#include "pico/btstack_run_loop_async_context.h"
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#include "hardware/sync.h"
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static void btstack_work_pending(async_context_t *context, async_when_pending_worker_t *worker);
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static SemaphoreHandle_t _run_loop_exit_binary;
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static void do_btstack_work_pending(void *data) {
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btstack_work_pending(NULL, NULL);
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}
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static void btstack_run_loop_freertos_native_init(void) {
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_run_loop_exit_binary = xSemaphoreCreateBinary();
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btstack_run_loop_base_init();
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}
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static void btstack_run_loop_freertos_native_add_data_source(btstack_data_source_t * data_source) {
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cyw43_thread_enter();
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btstack_run_loop_base_add_data_source(data_source);
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cyw43_thread_exit();
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}
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static bool btstack_run_loop_freertos_native_remove_data_source(btstack_data_source_t * data_source) {
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cyw43_thread_enter();
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bool rc = btstack_run_loop_base_remove_data_source(data_source);
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cyw43_thread_exit();
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return rc;
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}
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static void btstack_run_loop_freertos_native_enable_data_source_callbacks(btstack_data_source_t * data_source, uint16_t callbacks) {
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cyw43_thread_enter();
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btstack_run_loop_base_enable_data_source_callbacks(data_source, callbacks);
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cyw43_thread_exit();
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}
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static void btstack_run_loop_freertos_native_disable_data_source_callbacks(btstack_data_source_t * data_source, uint16_t callbacks) {
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cyw43_thread_enter();
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btstack_run_loop_base_disable_data_source_callbacks(data_source, callbacks);
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cyw43_thread_exit();
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}
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static void btstack_run_loop_freertos_native_set_timer(btstack_timer_source_t *ts, uint32_t timeout_in_ms) {
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cyw43_thread_enter();
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ts->timeout = to_ms_since_boot(get_absolute_time()) + timeout_in_ms + 1;
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lwip_callback(do_btstack_work_pending, NULL);
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cyw43_thread_exit();
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}
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static void btstack_run_loop_freertos_native_add_timer(btstack_timer_source_t *timer) {
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cyw43_thread_enter();
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btstack_run_loop_base_add_timer(timer);
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lwip_callback(do_btstack_work_pending, NULL);
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cyw43_thread_exit();
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}
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static bool btstack_run_loop_freertos_native_remove_timer(btstack_timer_source_t *timer) {
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cyw43_thread_enter();
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bool rc = btstack_run_loop_base_remove_timer(timer);
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cyw43_thread_exit();
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return rc;
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}
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static void btstack_run_loop_freertos_native_dump_timer(void) {
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cyw43_thread_enter();
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btstack_run_loop_base_dump_timer();
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cyw43_thread_exit();
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}
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static uint32_t btstack_run_loop_freertos_native_get_time_ms(void) {
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return to_ms_since_boot(get_absolute_time());
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}
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static void btstack_run_loop_freertos_native_execute(void) {
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// Try and take a binary semaphore that only the done-loop will give
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xSemaphoreTake(_run_loop_exit_binary, portMAX_DELAY);
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}
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static void btstack_run_loop_async_context_trigger_exit(void) {
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xSemaphoreGive(_run_loop_exit_binary);
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}
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static void btstack_run_loop_freertos_native_execute_on_main_thread(btstack_context_callback_registration_t *callback_registration) {
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cyw43_thread_enter();
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btstack_run_loop_base_add_callback(callback_registration);
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lwip_callback(do_btstack_work_pending, NULL);
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cyw43_thread_exit();
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}
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static void btstack_run_loop_freertos_native_poll_data_sources_from_irq(void) {
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lwip_callback(do_btstack_work_pending, NULL);
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}
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static const btstack_run_loop_t btstack_run_loop_freertos_native = {
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&btstack_run_loop_freertos_native_init,
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&btstack_run_loop_freertos_native_add_data_source,
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&btstack_run_loop_freertos_native_remove_data_source,
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&btstack_run_loop_freertos_native_enable_data_source_callbacks,
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&btstack_run_loop_freertos_native_disable_data_source_callbacks,
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&btstack_run_loop_freertos_native_set_timer,
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&btstack_run_loop_freertos_native_add_timer,
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&btstack_run_loop_freertos_native_remove_timer,
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&btstack_run_loop_freertos_native_execute,
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&btstack_run_loop_freertos_native_dump_timer,
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&btstack_run_loop_freertos_native_get_time_ms,
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&btstack_run_loop_freertos_native_poll_data_sources_from_irq,
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&btstack_run_loop_freertos_native_execute_on_main_thread,
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&btstack_run_loop_async_context_trigger_exit,
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};
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static alarm_id_t _timeout = -1;
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static int64_t cb_btstack_timeout_worker(alarm_id_t id, void *user_data) {
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static __callback_req _timeoutIRQBuffer;
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// This will be in IRQ context, so do a lwip callback. Only one at a time can be outstanding so this single struct is good enough
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_timeout = -1;
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lwip_callback(do_btstack_work_pending, NULL, &_timeoutIRQBuffer);
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return 0; // Don't reschedule
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}
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static void btstack_work_pending(__unused async_context_t *context, __unused async_when_pending_worker_t *worker) {
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// poll data sources
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btstack_run_loop_base_poll_data_sources();
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// execute callbacks
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btstack_run_loop_base_execute_callbacks();
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uint32_t now = to_ms_since_boot(get_absolute_time());
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// process timers
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btstack_run_loop_base_process_timers(now);
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now = to_ms_since_boot(get_absolute_time());
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int ms = btstack_run_loop_base_get_time_until_timeout(now);
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if (ms == -1) {
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if (_timeout != -1) {
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cancel_alarm(_timeout);
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_timeout = -1;
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}
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} else {
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_timeout = add_alarm_in_ms(ms, cb_btstack_timeout_worker, NULL, true);
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}
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}
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// The only exported function here...
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extern "C" const btstack_run_loop_t *__wrap_btstack_run_loop_async_context_get_instance(async_context_t *freertos_native) {
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return &btstack_run_loop_freertos_native;
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}
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#endif

‎lib/core_wrap.txt

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@@ -93,3 +93,4 @@
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-Wl,--wrap=cyw43_arch_wifi_connect_bssid_timeout_ms
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-Wl,--wrap=cyw43_arch_wifi_connect_timeout_ms
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-Wl,--wrap=cyw43_arch_gpio_put
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-Wl,--wrap=btstack_run_loop_async_context_get_instance

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