Add Pico W and lwIP support

.gitmodules

 [submodule "tinyusb"]
 	path = lib/tinyusb
 	url = https://github.com/hathach/tinyusb.git
+[submodule "lib/cyw43-driver"]
+	path = lib/cyw43-driver
+	url = https://github.com/georgerobotics/cyw43-driver.git
+[submodule "lib/lwip"]
+	path = lib/lwip
+	url = https://github.com/lwip-tcpip/lwip.git

README.md

@@ -110,6 +110,24 @@ instructions for other platforms, and just in general, we recommend you see [Ras
 
           ```
 
+   * Or by cloning the SDK locally, but without copying `pico_sdk_import.cmake`:
+       1. `git clone` this Raspberry Pi Pico SDK repository
+       2. Setup a `CMakeLists.txt` like:
+
+           ```cmake
+           cmake_minimum_required(VERSION 3.13)
+ 
+           # initialize the SDK directly
+           include(/path/to/pico-sdk/pico_sdk_init.cmake)
+ 
+           project(my_project)
+ 
+           # initialize the Raspberry Pi Pico SDK
+           pico_sdk_init()
+ 
+           # rest of your project
+ 
+           ```
 1. Write your code (see [pico-examples](https://github.com/raspberrypi/pico-examples) or the [Raspberry Pi Pico C/C++ SDK](https://rptl.io/pico-c-sdk) documentation for more information)
 
    About the simplest you can do is a single source file (e.g. hello_world.c)

docs/Doxyfile.in

@@ -60,4 +60,5 @@ PREDEFINED             = __not_in_flash_func(x) \
                          __time_critical_func(x) \
                          __not_in_flash(x)= \
                          __no_inline_not_in_flash(x)= \
-                         __attribute__(x)=
+                         __attribute__(x)= \
+                         DOXYGEN_GENERATION=

docs/index.h

@@ -56,6 +56,13 @@
  * \defgroup tinyusb_host tinyusb_host
  * @}
  *
+ * \defgroup networking Networking Libraries
+ * Functions for implementing networking
+ * @{
+ * \defgroup pico_lwip pico_lwip
+ * \defgroup pico_cyw43_arch pico_cyw43_arch
+ * @}
+ *
  * \defgroup runtime Runtime Infrastructure
  * Libraries that are used to provide efficient implementation of certain
  * language level and C library functions, as well as CMake INTERFACE libraries

cyw43-driver @ 195dfcc1

+Subproject commit 195dfcc10bb6f379e3dea45147590db2203d3c7b

lwip @ 239918cc

+Subproject commit 239918ccc173cb2c2a62f41a40fd893f57faf1d6

src/boards/include/boards/pico_w.h

+/*
+ * Copyright (c) 2022 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+// -----------------------------------------------------
+// NOTE: THIS HEADER IS ALSO INCLUDED BY ASSEMBLER SO
+//       SHOULD ONLY CONSIST OF PREPROCESSOR DIRECTIVES
+// -----------------------------------------------------
+
+// This header may be included by other board headers as "boards/pico.h"
+
+#ifndef _BOARDS_PICO_W_H
+#define _BOARDS_PICO_W_H
+
+// For board detection
+#define RASPBERRYPI_PICO_W
+
+// --- UART ---
+#ifndef PICO_DEFAULT_UART
+#define PICO_DEFAULT_UART 0
+#endif
+#ifndef PICO_DEFAULT_UART_TX_PIN
+#define PICO_DEFAULT_UART_TX_PIN 0
+#endif
+#ifndef PICO_DEFAULT_UART_RX_PIN
+#define PICO_DEFAULT_UART_RX_PIN 1
+#endif
+
+// --- LED ---
+// no PICO_DEFAULT_LED_PIN - LED is on Wireless chip
+// no PICO_DEFAULT_WS2812_PIN
+
+// --- I2C ---
+#ifndef PICO_DEFAULT_I2C
+#define PICO_DEFAULT_I2C 0
+#endif
+#ifndef PICO_DEFAULT_I2C_SDA_PIN
+#define PICO_DEFAULT_I2C_SDA_PIN 4
+#endif
+#ifndef PICO_DEFAULT_I2C_SCL_PIN
+#define PICO_DEFAULT_I2C_SCL_PIN 5
+#endif
+
+// --- SPI ---
+#ifndef PICO_DEFAULT_SPI
+#define PICO_DEFAULT_SPI 0
+#endif
+#ifndef PICO_DEFAULT_SPI_SCK_PIN
+#define PICO_DEFAULT_SPI_SCK_PIN 18
+#endif
+#ifndef PICO_DEFAULT_SPI_TX_PIN
+#define PICO_DEFAULT_SPI_TX_PIN 19
+#endif
+#ifndef PICO_DEFAULT_SPI_RX_PIN
+#define PICO_DEFAULT_SPI_RX_PIN 16
+#endif
+#ifndef PICO_DEFAULT_SPI_CSN_PIN
+#define PICO_DEFAULT_SPI_CSN_PIN 17
+#endif
+
+// --- FLASH ---
+
+#define PICO_BOOT_STAGE2_CHOOSE_W25Q080 1
+
+#ifndef PICO_FLASH_SPI_CLKDIV
+#define PICO_FLASH_SPI_CLKDIV 2
+#endif
+
+#ifndef PICO_FLASH_SIZE_BYTES
+#define PICO_FLASH_SIZE_BYTES (2 * 1024 * 1024)
+#endif
+
+// note the SMSP mode pin is on WL_GPIO1
+// #define PICO_SMPS_MODE_PIN
+
+#ifndef PICO_RP2040_B0_SUPPORTED
+#define PICO_RP2040_B0_SUPPORTED 0
+#endif
+
+#ifndef PICO_RP2040_B1_SUPPORTED
+#define PICO_RP2040_B1_SUPPORTED 0
+#endif
+
+#ifndef CYW43_PIN_WL_HOST_WAKE
+#define CYW43_PIN_WL_HOST_WAKE 24
+#endif
+
+#ifndef CYW43_PIN_WL_REG_ON
+#define CYW43_PIN_WL_REG_ON 23
+#endif
+
+#ifndef CYW43_WL_GPIO_COUNT
+#define CYW43_WL_GPIO_COUNT 3
+#endif
+
+#ifndef CYW43_WL_GPIO_LED_PIN
+#define CYW43_WL_GPIO_LED_PIN 0
+#endif
+
+#endif

src/boards/pico_w.cmake

+set(PICO_CYW43_SUPPORTED "1" CACHE INTERNAL "Try to add support for PICO_CYW43")
+include(${CMAKE_CURRENT_LIST_DIR}/generic_board.cmake)

src/common/pico_base/include/pico/error.h

@@ -10,14 +10,18 @@
 #ifndef __ASSEMBLER__
 
 /*!
- * Common return codes from pico_sdk methods that return a status
+ * \brief Common return codes from pico_sdk methods that return a status
+ * \ingroup pico_base
  */
-enum {
+enum pico_error_codes {
     PICO_OK = 0,
     PICO_ERROR_NONE = 0,
     PICO_ERROR_TIMEOUT = -1,
     PICO_ERROR_GENERIC = -2,
     PICO_ERROR_NO_DATA = -3,
+    PICO_ERROR_NOT_PERMITTED = -4,
+    PICO_ERROR_INVALID_ARG = -5,
+    PICO_ERROR_IO = -6,
 };
 
 #endif // !__ASSEMBLER__

src/rp2_common/CMakeLists.txt

@@ -58,6 +58,10 @@ if (NOT PICO_BARE_METAL)
     pico_add_subdirectory(tinyusb)
     pico_add_subdirectory(pico_stdio_usb)
 
+    pico_add_subdirectory(cyw43_driver)
+    pico_add_subdirectory(pico_lwip)
+    pico_add_subdirectory(pico_cyw43_arch)
+
     pico_add_subdirectory(pico_stdlib)
 
     pico_add_subdirectory(pico_cxx_options)

src/rp2_common/cyw43_driver/CMakeLists.txt

+if (DEFINED ENV{PICO_CYW43_DRIVER_PATH} AND (NOT PICO_CYW43_DRIVER_PATH))
+    set(PICO_CYW43_DRIVER_PATH $ENV{PICO_CYW43_DRIVER_PATH})
+    message("Using PICO_CYW43_DRIVER_PATH from environment ('${PICO_CYW43_DRIVER_PATH}')")
+endif()
+
+set(CYW43_DRIVER_TEST_FILE "src/cyw43.h")
+
+if (NOT PICO_CYW43_DRIVER_PATH)
+    set(PICO_CYW43_DRIVER_PATH ${PICO_SDK_PATH}/lib/cyw43-driver)
+    if (PICO_CYW43_SUPPORTED AND NOT EXISTS ${PICO_CYW43_DRIVER_PATH}/${CYW43_DRIVER_TEST_FILE})
+        message(WARNING "cyw43-driver submodule has not been initialized; Pico W wireless support will be unavailable
+hint: try 'git submodule update --init' from your SDK directory (${PICO_SDK_PATH}).")
+    endif()
+elseif (NOT EXISTS ${PICO_CYW43_DRIVER_PATH}/${CYW43_DRIVER_TEST_FILE})
+    message(WARNING "PICO_CYW43_DRIVER_PATH specified but content not present.")
+endif()
+
+if (EXISTS ${PICO_CYW43_DRIVER_PATH}/${CYW43_DRIVER_TEST_FILE})
+    message("cyw43-driver available at ${PICO_CYW43_DRIVER_PATH}")
+
+    pico_register_common_scope_var(PICO_CYW43_DRIVER_PATH)
+
+    # base driver without our bus
+    add_library(cyw43_driver_base INTERFACE)
+    target_sources(cyw43_driver_base INTERFACE
+            ${PICO_CYW43_DRIVER_PATH}/src/cyw43_ll.c
+            ${PICO_CYW43_DRIVER_PATH}/src/cyw43_stats.c
+            ${PICO_CYW43_DRIVER_PATH}/src/cyw43_lwip.c
+            ${PICO_CYW43_DRIVER_PATH}/src/cyw43_ctrl.c
+            )
+    target_include_directories(cyw43_driver_base INTERFACE
+            ${PICO_CYW43_DRIVER_PATH}/src
+            ${PICO_CYW43_DRIVER_PATH}/firmware
+            )
+
+    # Build the driver for cyw43 for pico w
+
+    # Firmware stuff
+    set(CYW43_FIRMWARE_BIN 43439A0-7.95.49.00.combined)
+    string(REGEX REPLACE [\\\.\-] _ CYW43_FIRMWARE_BIN_ ${CYW43_FIRMWARE_BIN})
+    string(REGEX MATCH [^_]+_?[^_]*_?[^_]*_?[^_]*_?[^_]* CYW43_FIRMWARE_PRETTY ${CYW43_FIRMWARE_BIN_})
+    set(CYW43_FIRMWARE_PRETTY fw_${CYW43_FIRMWARE_PRETTY})
+    set(RESOURCE_SECNAME .big_const)
+    set(RESOURCE_SECFLAGS contents,alloc,load,readonly,data)
+    set(CYW43_FIRMWARE_OBJ ${CMAKE_CURRENT_BINARY_DIR}/cyw43_resource.o)
+
+    add_custom_target(cyw43_firmware_package DEPENDS ${CYW43_FIRMWARE_OBJ})
+
+    # cyw43_resource.o contains the WiFi and BT firmware as a binary blob
+    add_custom_command(
+            OUTPUT ${CYW43_FIRMWARE_OBJ}
+            DEPENDS ${PICO_CYW43_DRIVER_PATH}/firmware/${CYW43_FIRMWARE_BIN}
+            WORKING_DIRECTORY ${PICO_CYW43_DRIVER_PATH}/firmware
+            COMMAND ${CMAKE_OBJCOPY} -I binary -O elf32-littlearm -B arm
+            --readonly-text
+            --rename-section .data=${RESOURCE_SECNAME},${RESOURCE_SECFLAGS}
+            --redefine-sym _binary_${CYW43_FIRMWARE_BIN_}_start=${CYW43_FIRMWARE_PRETTY}_start
+            --redefine-sym _binary_${CYW43_FIRMWARE_BIN_}_end=${CYW43_FIRMWARE_PRETTY}_end
+            --redefine-sym _binary_${CYW43_FIRMWARE_BIN_}_size=${CYW43_FIRMWARE_PRETTY}_size
+            ${CYW43_FIRMWARE_BIN} ${CYW43_FIRMWARE_OBJ}
+    )
+
+    add_library(cyw43_driver_picow INTERFACE)
+    target_sources(cyw43_driver_picow INTERFACE
+            ${CMAKE_CURRENT_LIST_DIR}/cyw43_bus_pio_spi.c
+            )
+    pico_generate_pio_header(cyw43_driver_picow ${CMAKE_CURRENT_LIST_DIR}/cyw43_bus_pio_spi.pio)
+    add_dependencies(cyw43_driver_picow INTERFACE cyw43_firmware_package)
+    target_link_libraries(cyw43_driver_picow INTERFACE
+            ${CYW43_FIRMWARE_OBJ}
+            )
+    target_link_libraries(cyw43_driver_picow INTERFACE
+            cyw43_driver_base
+            pico_stdlib
+            hardware_pio
+            hardware_dma
+            hardware_exception
+            )
+
+    pico_promote_common_scope_vars()
+endif()

src/rp2_common/cyw43_driver/cyw43_bus_pio_spi.pio

+;
+; Copyright (c) 2020 Raspberry Pi (Trading) Ltd.
+;
+; SPDX-License-Identifier: BSD-3-Clause
+;
+
+.program spi_gap0_sample1
+.side_set 1
+
+; always transmit multiple of 32 bytes
+lp: out pins, 1             side 0
+    jmp x-- lp              side 1
+public lp1_end:
+    set pindirs, 0          side 0
+lp2:
+    in pins, 1              side 1
+    jmp y-- lp2             side 0
+public end:
+
+.program spi_gap01_sample0
+.side_set 1
+
+; always transmit multiple of 32 bytes
+lp: out pins, 1             side 0
+    jmp x-- lp              side 1
+public lp1_end:
+    set pindirs, 0          side 0
+    nop                     side 1
+lp2:
+    in pins, 1              side 0
+    jmp y-- lp2             side 1
+public end:
+
+.program spi_gap010_sample1
+.side_set 1
+
+; always transmit multiple of 32 bytes
+lp: out pins, 1             side 0
+    jmp x-- lp              side 1
+public lp1_end:
+    set pindirs, 0          side 0
+    nop                     side 1
+    nop                     side 0
+lp2:
+    in pins, 1              side 1
+    jmp y-- lp2             side 0
+public end:
+
+.program spi_gap0_sample1_regular
+.side_set 1
+
+; always transmit multiple of 32 bytes
+lp: out pins, 1             side 0
+    jmp x-- lp              side 1
+public lp1_end:
+    set pindirs, 0          side 0
+lp2:
+    in pins, 1              side 1
+    jmp y-- lp2             side 0
+public end:
+

src/rp2_common/hardware_dma/dma.c

@@ -36,6 +36,12 @@ void dma_channel_unclaim(uint channel) {
     hw_claim_clear((uint8_t *) &_claimed, channel);
 }
 
+void dma_unclaim_mask(uint32_t mask) {
+    for(uint i = 0; mask; i++, mask >>= 1u) {
+        if (mask & 1u) dma_channel_unclaim(i);
+    }
+}
+
 int dma_claim_unused_channel(bool required) {
     return hw_claim_unused_from_range((uint8_t*)&_claimed, required, 0, NUM_DMA_CHANNELS-1, "No DMA channels are available");
 }

src/rp2_common/hardware_dma/include/hardware/dma.h

@@ -88,12 +88,17 @@ void dma_claim_mask(uint32_t channel_mask);
 /*! \brief Mark a dma channel as no longer used
  *  \ingroup hardware_dma
  *
- * Method for cooperative claiming of hardware.
- *
  * \param channel the dma channel to release
  */
 void dma_channel_unclaim(uint channel);
 
+/*! \brief Mark multiple dma channels as no longer used
+ *  \ingroup hardware_dma
+ *
+ * \param channel_mask Bitfield of all channels to unclaim (bit 0 == channel 0, bit 1 == channel 1 etc)
+ */
+void dma_unclaim_mask(uint32_t channel_mask);
+
 /*! \brief Claim a free dma channel
  *  \ingroup hardware_dma
  *

src/rp2_common/pico_cyw43_arch/CMakeLists.txt

+if (PICO_CYW43_SUPPORTED) # set by BOARD=pico-w
+    if (TARGET cyw43_driver_picow)
+        message("Enabling build support for Pico W wireless.")
+
+        pico_add_impl_library(pico_cyw43_arch)
+        target_sources(pico_cyw43_arch INTERFACE
+                ${CMAKE_CURRENT_LIST_DIR}/cyw43_arch.c
+                ${CMAKE_CURRENT_LIST_DIR}/cyw43_arch_poll.c
+                ${CMAKE_CURRENT_LIST_DIR}/cyw43_arch_threadsafe_background.c
+                ${CMAKE_CURRENT_LIST_DIR}/cyw43_arch_freertos.c
+                )
+
+        target_include_directories(pico_cyw43_arch INTERFACE
+                ${CMAKE_CURRENT_LIST_DIR}/include)
+
+        target_link_libraries(pico_cyw43_arch INTERFACE
+                pico_unique_id
+                cyw43_driver_picow)
+
+        if (NOT TARGET pico_lwip)
+            message(WARNING "lwIP is not available; Full Pico W wireless support will be unavailable too")
+        else()
+            add_library(pico_cyw43_arch_lwip_poll INTERFACE)
+            target_link_libraries(pico_cyw43_arch_lwip_poll INTERFACE
+                    pico_cyw43_arch
+                    pico_lwip
+                    pico_lwip_nosys)
+            target_compile_definitions(pico_cyw43_arch_lwip_poll INTERFACE
+                    CYW43_LWIP=1
+                    PICO_CYW43_ARCH_POLL=1
+                    )
+
+            add_library(pico_cyw43_arch_lwip_threadsafe_background INTERFACE)
+            target_link_libraries(pico_cyw43_arch_lwip_threadsafe_background INTERFACE
+                    pico_cyw43_arch
+                    pico_lwip
+                    pico_lwip_nosys)
+            target_compile_definitions(pico_cyw43_arch_lwip_threadsafe_background INTERFACE
+                    CYW43_LWIP=1
+                    PICO_CYW43_ARCH_THREADSAFE_BACKGROUND=1
+                    )
+
+            add_library(pico_cyw43_arch_lwip_sys_freertos INTERFACE)
+            target_link_libraries(pico_cyw43_arch_lwip_sys_freertos INTERFACE
+                    pico_cyw43_arch
+                    pico_lwip
+                    pico_lwip_contrib_freertos)
+            target_compile_definitions(pico_cyw43_arch_lwip_sys_freertos INTERFACE
+                    CYW43_LWIP=1
+                    LWIP_PROVIDE_ERRNO=1
+                    PICO_CYW43_ARCH_FREERTOS=1
+                    )
+        endif()
+
+        add_library(pico_cyw43_arch_none INTERFACE)
+        target_link_libraries(pico_cyw43_arch_none INTERFACE pico_cyw43_arch)
+        target_compile_definitions(pico_cyw43_arch_none INTERFACE
+                CYW43_LWIP=0
+                PICO_CYW43_ARCH_THREADSAFE_BACKGROUND=1 # none still uses threadsafe_background to make gpio use easy
+                )
+    endif()
+endif()
+
+if (PICO_CYW43_DRIVER_PATH AND EXISTS "${PICO_CYW43_DRIVER_PATH}")
+    pico_add_doxygen(${PICO_CYW43_DRIVER_PATH}/src)
+endif()
\ No newline at end of file

src/rp2_common/pico_cyw43_arch/cyw43_arch.c

+/*
+ * Copyright (c) 2022 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "pico/unique_id.h"
+#include "cyw43.h"
+#include "pico/cyw43_arch.h"
+#include "cyw43_ll.h"
+#include "cyw43_stats.h"
+
+#if CYW43_ARCH_DEBUG_ENABLED
+#define CYW43_ARCH_DEBUG(...) printf(__VA_ARGS__)
+#else
+#define CYW43_ARCH_DEBUG(...) ((void)0)
+#endif
+
+static uint32_t country_code = PICO_CYW43_ARCH_DEFAULT_COUNTRY_CODE;
+
+void cyw43_arch_enable_sta_mode() {
+    assert(cyw43_is_initialized(&cyw43_state));
+    cyw43_wifi_set_up(&cyw43_state, CYW43_ITF_STA, true, cyw43_arch_get_country_code());
+}
+
+void cyw43_arch_enable_ap_mode(const char *ssid, const char *password, uint32_t auth) {
+    assert(cyw43_is_initialized(&cyw43_state));
+    cyw43_wifi_ap_set_ssid(&cyw43_state, strlen(ssid), (const uint8_t *) ssid);
+    if (password) {
+        cyw43_wifi_ap_set_password(&cyw43_state, strlen(password), (const uint8_t *) password);
+        cyw43_wifi_ap_set_auth(&cyw43_state, auth);
+    } else {
+        cyw43_wifi_ap_set_auth(&cyw43_state, CYW43_AUTH_OPEN);
+    }
+    cyw43_wifi_set_up(&cyw43_state, CYW43_ITF_AP, true, cyw43_arch_get_country_code());
+}
+
+#if CYW43_ARCH_DEBUG_ENABLED
+// Return a string for the wireless state
+static const char* status_name(int status)
+{
+    switch (status) {
+    case CYW43_LINK_DOWN:
+        return "link down";
+    case CYW43_LINK_JOIN:
+        return "joining";
+    case CYW43_LINK_NOIP:
+        return "no ip";
+    case CYW43_LINK_UP:
+        return "link up";
+    case CYW43_LINK_FAIL:
+        return "link fail";
+    case CYW43_LINK_NONET:
+        return "network fail";
+    case CYW43_LINK_BADAUTH:
+        return "bad auth";
+    }
+    return "unknown";
+}
+#endif
+
+int cyw43_arch_wifi_connect_async(const char *ssid, const char *pw, uint32_t auth) {
+    if (!pw) auth = CYW43_AUTH_OPEN;
+    // Connect to wireless
+    return cyw43_wifi_join(&cyw43_state, strlen(ssid), (const uint8_t *)ssid, pw ? strlen(pw) : 0, (const uint8_t *)pw, auth, NULL, CYW43_ITF_STA);
+}
+
+// Connect to wireless, return with success when an IP address has been assigned
+int cyw43_arch_wifi_connect_until(const char *ssid, const char *pw, uint32_t auth, absolute_time_t until) {
+    int err = cyw43_arch_wifi_connect_async(ssid, pw, auth);
+    if (err) return err;
+
+    int status = CYW43_LINK_UP + 1;
+    while(status >= 0 && status != CYW43_LINK_UP) {
+        int new_status = cyw43_tcpip_link_status(&cyw43_state, CYW43_ITF_STA);
+        if (new_status != status) {
+            status = new_status;
+            CYW43_ARCH_DEBUG("connect status: %s\n", status_name(status));
+        }
+        // in case polling is required
+        cyw43_arch_poll();
+        best_effort_wfe_or_timeout(until);
+        if (time_reached(until)) {
+            return PICO_ERROR_TIMEOUT;
+        }
+    }
+    return status == CYW43_LINK_UP ? 0 : status;
+}
+
+int cyw43_arch_wifi_connect_blocking(const char *ssid, const char *pw, uint32_t auth) {
+    return cyw43_arch_wifi_connect_until(ssid, pw, auth, at_the_end_of_time);
+}
+
+int cyw43_arch_wifi_connect_timeout_ms(const char *ssid, const char *pw, uint32_t auth, uint32_t timeout_ms) {
+    return cyw43_arch_wifi_connect_until(ssid, pw, auth, make_timeout_time_ms(timeout_ms));
+}
+
+// todo maybe add an #ifdef in cyw43_driver
+uint32_t storage_read_blocks(__unused uint8_t *dest, __unused uint32_t block_num, __unused uint32_t num_blocks) {
+    // shouldn't be used
+    panic_unsupported();
+}
+
+// Generate a mac address if one is not set in otp
+void cyw43_hal_generate_laa_mac(__unused int idx, uint8_t buf[6]) {
+    CYW43_DEBUG("Warning. No mac in otp. Generating mac from board id\n");
+    pico_unique_board_id_t board_id;
+    pico_get_unique_board_id(&board_id);
+    memcpy(buf, &board_id.id[2], 6);
+    buf[0] &= (uint8_t)~0x1; // unicast
+    buf[0] |= 0x2; // locally administered
+}
+
+// Return mac address
+void cyw43_hal_get_mac(__unused int idx, uint8_t buf[6]) {
+    // The mac should come from cyw43 otp.
+    // This is loaded into the state after the driver is initialised
+    // cyw43_hal_generate_laa_mac is called by the driver to generate a mac if otp is not set
+    memcpy(buf, cyw43_state.mac, 6);
+}
+
+uint32_t cyw43_arch_get_country_code(void) {
+    return country_code;
+}
+
+int cyw43_arch_init_with_country(uint32_t country) {
+    country_code = country;
+    return cyw43_arch_init();
+}
+
+void cyw43_arch_gpio_put(uint wl_gpio, bool value) {
+    invalid_params_if(CYW43_ARCH, wl_gpio >= CYW43_WL_GPIO_COUNT);
+    cyw43_gpio_set(&cyw43_state, (int)wl_gpio, value);
+}
+
+bool cyw43_arch_gpio_get(uint wl_gpio) {
+    invalid_params_if(CYW43_ARCH, wl_gpio >= CYW43_WL_GPIO_COUNT);
+    bool value = false;
+    cyw43_gpio_get(&cyw43_state, (int)wl_gpio, &value);
+    return value;
+}

src/rp2_common/pico_cyw43_arch/cyw43_arch_freertos.c

+/*
+ * Copyright (c) 2022 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdio.h>
+
+#include "pico/cyw43_arch.h"
+
+#include "hardware/gpio.h"
+#include "hardware/irq.h"
+#include "hardware/sync.h"
+
+#include "cyw43_stats.h"
+
+#if CYW43_LWIP
+#include <lwip/tcpip.h>
+#endif
+
+#if PICO_CYW43_ARCH_FREERTOS
+
+// FreeRTOS includes
+#include "FreeRTOS.h"
+#include "timers.h"
+#include "semphr.h"
+
+#if NO_SYS
+#error example_cyw43_arch_frertos_sys requires NO_SYS=0
+#endif
+
+#ifndef CYW43_TASK_PRIORITY
+#define CYW43_TASK_PRIORITY ( tskIDLE_PRIORITY + 4)
+#endif
+
+#ifndef CYW43_SLEEP_CHECK_MS
+#define CYW43_SLEEP_CHECK_MS 50 // How often to run lwip callback
+#endif
+
+#define CYW43_GPIO_IRQ_HANDLER_PRIORITY 0x40
+
+static void signal_cyw43_task(void);
+
+#if !LWIP_TCPIP_CORE_LOCKING_INPUT
+static SemaphoreHandle_t cyw43_mutex;
+#endif
+static TimerHandle_t timer_handle;
+static TaskHandle_t cyw43_task_handle;
+static volatile bool cyw43_task_should_exit;
+static SemaphoreHandle_t cyw43_worker_ran_sem;
+static uint8_t cyw43_core_num;
+
+// Called in low priority pendsv interrupt only to do lwip processing and check cyw43 sleep
+static void periodic_worker(__unused TimerHandle_t handle)
+{
+#if CYW43_USE_STATS
+    static uint32_t counter;
+    if (counter++ % (30000 / LWIP_SYS_CHECK_MS) == 0) {
+        cyw43_dump_stats();
+    }
+#endif
+
+    CYW43_STAT_INC(LWIP_RUN_COUNT);
+    if (cyw43_poll) {
+        if (cyw43_sleep > 0) {
+            if (--cyw43_sleep == 0) {
+                signal_cyw43_task();
+            }
+        }
+    }
+}
+
+void cyw43_await_background_or_timeout_us(uint32_t timeout_us) {
+    // if we are called from within an IRQ, then don't wait (we are only ever called in a polling loop)
+    assert(!portCHECK_IF_IN_ISR());
+    xSemaphoreTake(cyw43_worker_ran_sem, pdMS_TO_TICKS(timeout_us / 1000));
+}
+
+// GPIO interrupt handler to tell us there's cyw43 has work to do
+static void gpio_irq_handler(void)
+{
+    uint32_t events = gpio_get_irq_event_mask(CYW43_PIN_WL_HOST_WAKE);
+    if (events & GPIO_IRQ_LEVEL_HIGH) {
+        // As we use a high level interrupt, it will go off forever until it's serviced
+        // So disable the interrupt until this is done. It's re-enabled again by CYW43_POST_POLL_HOOK
+        // which is called at the end of cyw43_poll_func
+        gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, false);
+        signal_cyw43_task();
+        CYW43_STAT_INC(IRQ_COUNT);
+    }
+}
+
+// Low priority interrupt handler to perform background processing
+static void cyw43_task(__unused void *param) {
+    do {
+        ulTaskNotifyTake(pdFALSE, portMAX_DELAY);
+        if (cyw43_task_should_exit) break;
+        cyw43_thread_enter();
+        if (cyw43_poll) cyw43_poll();
+        cyw43_thread_exit();
+        xSemaphoreGive(cyw43_worker_ran_sem);
+        __sev(); // it is possible regular code is waiting on a WFE on the other core
+    } while (true);
+}
+
+static void tcpip_init_done(void *param) {
+    xSemaphoreGive((SemaphoreHandle_t)param);
+}
+
+int cyw43_arch_init(void) {
+    cyw43_core_num = get_core_num();
+#if configUSE_CORE_AFFINITY && configNUM_CORES > 1
+    TaskHandle_t task_handle = xTaskGetCurrentTaskHandle();
+    UBaseType_t affinity = vTaskCoreAffinityGet(task_handle);
+    // we must bind the main task to one core during init
+    vTaskCoreAffinitySet(task_handle, 1 << portGET_CORE_ID());
+#endif
+#if !LWIP_TCPIP_CORE_LOCKING_INPUT
+    cyw43_mutex = xSemaphoreCreateRecursiveMutex();
+#endif
+    cyw43_init(&cyw43_state);
+    cyw43_worker_ran_sem = xSemaphoreCreateBinary();
+
+#if CYW43_LWIP
+    SemaphoreHandle_t init_sem = xSemaphoreCreateBinary();
+    tcpip_init(tcpip_init_done, init_sem);
+    xSemaphoreTake(init_sem, portMAX_DELAY);
+#endif
+
+    timer_handle = xTimerCreate(    "cyw43_sleep_timer",       // Just a text name, not used by the kernel.
+                                    pdMS_TO_TICKS(CYW43_SLEEP_CHECK_MS),
+                                    pdTRUE,        // The timers will auto-reload themselves when they expire.
+                                    NULL,
+                                    periodic_worker);
+
+    if (!timer_handle) {
+        return PICO_ERROR_GENERIC;
+    }
+
+    gpio_add_raw_irq_handler_with_order_priority(IO_IRQ_BANK0, gpio_irq_handler, CYW43_GPIO_IRQ_HANDLER_PRIORITY);
+    gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, true);
+    irq_set_enabled(IO_IRQ_BANK0, true);
+
+    cyw43_task_should_exit = false;
+    xTaskCreate(cyw43_task, "CYW43 Worker", configMINIMAL_STACK_SIZE, NULL, CYW43_TASK_PRIORITY, &cyw43_task_handle);
+#if configUSE_CORE_AFFINITY && configNUM_CORES > 1
+    // the cyw43 task mus tbe on the same core so it can restore IRQs
+    vTaskCoreAffinitySet(cyw43_task_handle, 1 << portGET_CORE_ID());
+#endif
+
+#if configUSE_CORE_AFFINITY && configNUM_CORES > 1
+    vTaskCoreAffinitySet(task_handle, affinity);
+#endif
+
+    return PICO_OK;
+}
+
+void cyw43_arch_deinit(void) {
+    assert(cyw43_core_num == get_core_num());
+    if (timer_handle) {
+        xTimerDelete(timer_handle, 0);
+        timer_handle = 0;
+    }
+    if (cyw43_task_handle) {
+        cyw43_task_should_exit = true;
+        signal_cyw43_task();
+    }
+    gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, false);
+    gpio_remove_raw_irq_handler(IO_IRQ_BANK0, gpio_irq_handler);
+}
+
+void cyw43_post_poll_hook(void) {
+    assert(cyw43_core_num == get_core_num());
+    gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, true);
+}
+
+// This is called in the gpio and low_prio_irq interrupts and on either core
+static void signal_cyw43_task(void) {
+    if (cyw43_task_handle) {
+        if (portCHECK_IF_IN_ISR()) {
+            vTaskNotifyGiveFromISR(cyw43_task_handle, NULL);
+        } else {
+            xTaskNotifyGive(cyw43_task_handle);
+        }
+    }
+}
+
+void cyw43_schedule_internal_poll_dispatch(void (*func)(void)) {
+    assert(func == cyw43_poll);
+    signal_cyw43_task();
+}
+
+static int nesting;
+// Prevent background processing in pensv and access by the other core
+// These methods are called in pensv context and on either core
+// They can be called recursively
+void cyw43_thread_enter(void) {
+    // Lock the other core and stop low_prio_irq running
+    assert(!portCHECK_IF_IN_ISR());
+#if LWIP_TCPIP_CORE_LOCKING_INPUT
+    // we must share their mutex otherwise we can get deadlocks with two different recursive mutexes
+    LOCK_TCPIP_CORE();
+#else
+    xSemaphoreTakeRecursive(cyw43_mutex, portMAX_DELAY);
+#endif
+    nesting++;
+}
+
+#ifndef NDEBUG
+void cyw43_thread_lock_check(void) {
+    // Lock the other core and stop low_prio_irq running
+#if LWIP_TCPIP_CORE_LOCKING_INPUT
+    assert(xSemaphoreGetMutexHolder(lock_tcpip_core.mut) == xTaskGetCurrentTaskHandle());
+#else
+    assert(xSemaphoreGetMutexHolder(cyw43_mutex) == xTaskGetCurrentTaskHandle());
+#endif
+}
+#endif
+
+// Re-enable background processing
+void cyw43_thread_exit(void) {
+    // Run low_prio_irq if needed
+    --nesting;
+#if LWIP_TCPIP_CORE_LOCKING_INPUT
+    // we must share their mutex otherwise we can get deadlocks with two different recursive mutexes
+    UNLOCK_TCPIP_CORE();
+#else
+    xSemaphoreGiveRecursive(cyw43_mutex);
+#endif
+
+    if (!nesting && cyw43_task_handle != xTaskGetCurrentTaskHandle())
+        signal_cyw43_task();
+}
+
+void cyw43_delay_ms(uint32_t ms) {
+    assert(!portCHECK_IF_IN_ISR());
+    vTaskDelay(pdMS_TO_TICKS(ms));
+}
+
+void cyw43_delay_us(uint32_t us) {
+    if (us >= 1000) {
+        cyw43_delay_ms(us / 1000);
+    } else {
+        vTaskDelay(1);
+    }
+}
+
+void cyw43_arch_poll() {
+}
+
+#endif
\ No newline at end of file

src/rp2_common/pico_cyw43_arch/cyw43_arch_poll.c

+/*
+ * Copyright (c) 2022 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdio.h>
+#include "hardware/gpio.h"
+#include "hardware/irq.h"
+#include "pico/sem.h"
+#include "pico/cyw43_arch.h"
+#include "cyw43_stats.h"
+
+#if PICO_CYW43_ARCH_POLL
+#include <lwip/init.h>
+#include "lwip/timeouts.h"
+
+#if CYW43_LWIP && !NO_SYS
+#error PICO_CYW43_ARCH_POLL requires lwIP NO_SYS=1
+#endif
+
+#define CYW43_GPIO_IRQ_HANDLER_PRIORITY 0x40
+
+#ifndef NDEBUG
+uint8_t cyw43_core_num;
+#endif
+
+bool cyw43_poll_required;
+
+// GPIO interrupt handler to tell us there's cyw43 has work to do
+static void gpio_irq_handler(void)
+{
+    uint32_t events = gpio_get_irq_event_mask(CYW43_PIN_WL_HOST_WAKE);
+    if (events & GPIO_IRQ_LEVEL_HIGH) {
+        // As we use a high level interrupt, it will go off forever until it's serviced
+        // So disable the interrupt until this is done. It's re-enabled again by CYW43_POST_POLL_HOOK
+        // which is called at the end of cyw43_poll_func
+        gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, false);
+        // also clear the force bit which we use to programmatically cause this handler to fire (on the right core)
+        io_irq_ctrl_hw_t *irq_ctrl_base = get_core_num() ?
+                                          &iobank0_hw->proc1_irq_ctrl : &iobank0_hw->proc0_irq_ctrl;
+        hw_clear_bits(&irq_ctrl_base->intf[CYW43_PIN_WL_HOST_WAKE/8], GPIO_IRQ_LEVEL_HIGH << (4 * (CYW43_PIN_WL_HOST_WAKE & 7)));
+        cyw43_schedule_internal_poll_dispatch(cyw43_poll);
+        CYW43_STAT_INC(IRQ_COUNT);
+    }
+}
+
+void cyw43_post_poll_hook(void) {
+    gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, true);
+}
+
+int cyw43_arch_init(void) {
+#ifndef NDEBUG
+    cyw43_core_num = (uint8_t)get_core_num();
+#endif
+    cyw43_init(&cyw43_state);
+    static bool done_lwip_init;
+    if (!done_lwip_init) {
+        lwip_init();
+        done_lwip_init = true;
+    }
+    gpio_add_raw_irq_handler_with_order_priority(IO_IRQ_BANK0, gpio_irq_handler, CYW43_GPIO_IRQ_HANDLER_PRIORITY);
+    gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, true);
+    irq_set_enabled(IO_IRQ_BANK0, true);
+    return 0;
+}
+
+void cyw43_arch_deinit(void) {
+    gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, false);
+    gpio_remove_raw_irq_handler(IO_IRQ_BANK0, gpio_irq_handler);
+    cyw43_deinit(&cyw43_state);
+}
+
+
+void cyw43_schedule_internal_poll_dispatch(__unused void (*func)(void)) {
+    cyw43_poll_required = true;
+}
+
+void cyw43_arch_poll(void)
+{
+    CYW43_STAT_INC(LWIP_RUN_COUNT);
+    sys_check_timeouts();
+    if (cyw43_poll) {
+        if (cyw43_sleep > 0) {
+            // todo check this; but we don't want to advance too quickly
+            static absolute_time_t last_poll_time;
+            absolute_time_t current = get_absolute_time();
+            if (absolute_time_diff_us(last_poll_time, current) > 1000) {
+                if (--cyw43_sleep == 0) {
+                    cyw43_poll_required = 1;
+                }
+                last_poll_time = current;
+            }
+        }
+        // todo graham i removed this because otherwise polling can do nothing during connect.
+        //  in the polling only case, the caller is responsible for throttling how often they call anyway.
+        //  The alternative would be to have the call to this function from the init set the poll_required flag first
+//        if (cyw43_poll_required) {
+            cyw43_poll();
+//            cyw43_poll_required = false;
+//        }
+    }
+}
+
+#ifndef NDEBUG
+void cyw43_thread_check() {
+    if (__get_current_exception() || get_core_num() != cyw43_core_num) {
+        panic("cyw43_thread_lock_check failed");
+    }
+}
+#endif
+
+#endif
\ No newline at end of file

src/rp2_common/pico_cyw43_arch/cyw43_arch_threadsafe_background.c

+/*
+ * Copyright (c) 2022 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stdio.h>
+
+#include "pico/cyw43_arch.h"
+#include "pico/mutex.h"
+#include "pico/sem.h"
+
+#include "hardware/gpio.h"
+#include "hardware/irq.h"
+
+#include "cyw43_stats.h"
+
+#if CYW43_LWIP
+#include <lwip/init.h>
+#include "lwip/timeouts.h"
+#endif
+
+// note same code
+#if PICO_CYW43_ARCH_THREADSAFE_BACKGROUND
+
+#if PICO_CYW43_ARCH_THREADSAFE_BACKGROUND && CYW43_LWIP && !NO_SYS
+#error PICO_CYW43_ARCH_THREADSAFE_BACKGROUND requires lwIP NO_SYS=1
+#endif
+#if PICO_CYW43_ARCH_THREADSAFE_BACKGROUND && CYW43_LWIP && MEM_LIBC_MALLOC
+#error MEM_LIBC_MALLOC is incompatible with PICO_CYW43_ARCH_THREADSAFE_BACKGROUND
+#endif
+// todo right now we are now always doing a cyw43_dispatch along with a lwip one when hopping cores in low_prio_irq_schedule_dispatch
+
+#ifndef CYW43_SLEEP_CHECK_MS
+#define CYW43_SLEEP_CHECK_MS 50 // How often to run lwip callback
+#endif
+static alarm_id_t periodic_alarm = -1;
+
+static inline uint recursive_mutex_enter_count(recursive_mutex_t *mutex) {
+    return mutex->enter_count;
+}
+
+static inline lock_owner_id_t recursive_mutex_owner(recursive_mutex_t *mutex) {
+    return mutex->owner;
+}
+
+#define CYW43_GPIO_IRQ_HANDLER_PRIORITY 0x40
+
+enum {
+    CYW43_DISPATCH_SLOT_CYW43 = 0,
+    CYW43_DISPATCH_SLOT_ADAPTER,
+    CYW43_DISPATCH_SLOT_ENUM_COUNT
+};
+#ifndef CYW43_DISPATCH_SLOT_COUNT
+#define CYW43_DISPATCH_SLOT_COUNT CYW43_DISPATCH_SLOT_ENUM_COUNT
+#endif
+
+typedef void (*low_prio_irq_dispatch_t)(void);
+static void low_prio_irq_schedule_dispatch(size_t slot, low_prio_irq_dispatch_t f);
+
+static uint8_t cyw43_core_num;
+#ifndef NDEBUG
+static bool in_low_priority_irq;
+#endif
+static uint8_t low_priority_irq_num;
+static bool low_priority_irq_missed;
+static low_prio_irq_dispatch_t low_priority_irq_dispatch_slots[CYW43_DISPATCH_SLOT_COUNT];
+static recursive_mutex_t cyw43_mutex;
+semaphore_t cyw43_irq_sem;
+
+// Called in low priority pendsv interrupt only to do lwip processing and check cyw43 sleep
+static void periodic_worker(void)
+{
+#if CYW43_USE_STATS
+    static uint32_t counter;
+    if (counter++ % (30000 / LWIP_SYS_CHECK_MS) == 0) {
+        cyw43_dump_stats();
+    }
+#endif
+
+    CYW43_STAT_INC(LWIP_RUN_COUNT);
+#if CYW43_LWIP
+    sys_check_timeouts();
+#endif
+    if (cyw43_poll) {
+        if (cyw43_sleep > 0) {
+            if (--cyw43_sleep == 0) {
+                low_prio_irq_schedule_dispatch(CYW43_DISPATCH_SLOT_CYW43, cyw43_poll);
+            }
+        }
+    }
+}
+
+// Regular callback to get lwip to check for timeouts
+static int64_t periodic_alarm_handler(__unused alarm_id_t id, __unused void *user_data)
+{
+    // Do lwip processing in low priority pendsv interrupt
+    low_prio_irq_schedule_dispatch(CYW43_DISPATCH_SLOT_ADAPTER, periodic_worker);
+    return CYW43_SLEEP_CHECK_MS * 1000;
+}
+
+void cyw43_await_background_or_timeout_us(uint32_t timeout_us) {
+    // if we are called from within an IRQ, then don't wait (we are only ever called in a polling loop)
+    if (!__get_current_exception()) {
+        sem_acquire_timeout_us(&cyw43_irq_sem, timeout_us);
+    }
+}
+
+// GPIO interrupt handler to tell us there's cyw43 has work to do
+static void gpio_irq_handler(void)
+{
+    uint32_t events = gpio_get_irq_event_mask(CYW43_PIN_WL_HOST_WAKE);
+    if (events & GPIO_IRQ_LEVEL_HIGH) {
+        // As we use a high level interrupt, it will go off forever until it's serviced
+        // So disable the interrupt until this is done. It's re-enabled again by CYW43_POST_POLL_HOOK
+        // which is called at the end of cyw43_poll_func
+        gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, false);
+        // also clear the force bit which we use to progratically cause this handler to fire (on the right core)
+        io_irq_ctrl_hw_t *irq_ctrl_base = get_core_num() ?
+                                          &iobank0_hw->proc1_irq_ctrl : &iobank0_hw->proc0_irq_ctrl;
+        hw_clear_bits(&irq_ctrl_base->intf[CYW43_PIN_WL_HOST_WAKE/8], GPIO_IRQ_LEVEL_HIGH << (4 * (CYW43_PIN_WL_HOST_WAKE & 7)));
+        low_prio_irq_schedule_dispatch(CYW43_DISPATCH_SLOT_CYW43, cyw43_poll);
+        CYW43_STAT_INC(IRQ_COUNT);
+    }
+}
+
+// Low priority interrupt handler to perform background processing
+static void low_priority_irq_handler(void) {
+    assert(cyw43_core_num == get_core_num());
+    if (recursive_mutex_try_enter(&cyw43_mutex, NULL)) {
+        if (recursive_mutex_enter_count(&cyw43_mutex) != 1) {
+            low_priority_irq_missed = true;
+            CYW43_STAT_INC(PENDSV_DISABLED_COUNT);
+        } else {
+            CYW43_STAT_INC(PENDSV_RUN_COUNT);
+#ifndef NDEBUG
+            in_low_priority_irq = true;
+#endif
+            for (size_t i = 0; i < count_of(low_priority_irq_dispatch_slots); i++) {
+                if (low_priority_irq_dispatch_slots[i] != NULL) {
+                    low_prio_irq_dispatch_t f = low_priority_irq_dispatch_slots[i];
+                    low_priority_irq_dispatch_slots[i] = NULL;
+                    f();
+                }
+            }
+#ifndef NDEBUG
+            in_low_priority_irq = false;
+#endif
+        }
+        recursive_mutex_exit(&cyw43_mutex);
+    } else {
+        CYW43_STAT_INC(PENDSV_DISABLED_COUNT);
+        low_priority_irq_missed = true;
+    }
+    sem_release(&cyw43_irq_sem);
+}
+
+static bool low_prio_irq_init(uint8_t priority) {
+    assert(get_core_num() == cyw43_core_num);
+    int irq = user_irq_claim_unused(false);
+    if (irq < 0) return false;
+    low_priority_irq_num = (uint8_t) irq;
+    irq_set_exclusive_handler(low_priority_irq_num, low_priority_irq_handler);
+    irq_set_enabled(low_priority_irq_num, true);
+    irq_set_priority(low_priority_irq_num, priority);
+    return true;
+}
+
+static void low_prio_irq_deinit(void) {
+    if (low_priority_irq_num > 0) {
+        irq_set_enabled(low_priority_irq_num, false);
+        irq_remove_handler(low_priority_irq_num, low_priority_irq_handler);
+        user_irq_unclaim(low_priority_irq_num);
+        low_priority_irq_num = 0;
+    }
+}
+
+int cyw43_arch_init(void) {
+    cyw43_core_num = get_core_num();
+    recursive_mutex_init(&cyw43_mutex);
+    cyw43_init(&cyw43_state);
+    sem_init(&cyw43_irq_sem, 0, 1);
+
+    // Start regular lwip callback to handle timeouts
+    periodic_alarm = add_alarm_in_us(CYW43_SLEEP_CHECK_MS * 1000, periodic_alarm_handler, NULL, true);
+    if (periodic_alarm < 0) {
+        return PICO_ERROR_GENERIC;
+    }
+
+    gpio_add_raw_irq_handler_with_order_priority(IO_IRQ_BANK0, gpio_irq_handler, CYW43_GPIO_IRQ_HANDLER_PRIORITY);
+    gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, true);
+    irq_set_enabled(IO_IRQ_BANK0, true);
+
+#if CYW43_LWIP
+    lwip_init();
+#endif
+    // start low priority handler (no background work is done before this)
+    bool ok = low_prio_irq_init(PICO_LOWEST_IRQ_PRIORITY);
+    if (!ok) {
+        cyw43_arch_deinit();
+        return PICO_ERROR_GENERIC;
+    }
+    return PICO_OK;
+}
+
+void cyw43_arch_deinit(void) {
+    if (periodic_alarm >= 0) {
+        cancel_alarm(periodic_alarm);
+        periodic_alarm = -1;
+    }
+    gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, false);
+    gpio_remove_raw_irq_handler(IO_IRQ_BANK0, gpio_irq_handler);
+    low_prio_irq_deinit();
+}
+
+void cyw43_post_poll_hook(void) {
+    gpio_set_irq_enabled(CYW43_PIN_WL_HOST_WAKE, GPIO_IRQ_LEVEL_HIGH, true);
+}
+
+// This is called in the gpio and low_prio_irq interrupts and on either core
+static void low_prio_irq_schedule_dispatch(size_t slot, low_prio_irq_dispatch_t f) {
+    assert(slot < count_of(low_priority_irq_dispatch_slots));
+    low_priority_irq_dispatch_slots[slot] = f;
+    if (cyw43_core_num == get_core_num()) {
+        //on same core, can dispatch directly
+        irq_set_pending(low_priority_irq_num);
+    } else {
+        // on wrong core, so force via GPIO IRQ which itself calls this method for the CYW43 slot.
+        // since the CYW43 slot always uses the same function, this is fine with the addition of an
+        // extra (but harmless) CYW43 slot call when another SLOT is invoked.
+        // We could do better, but would have to track why the IRQ was called.
+        io_irq_ctrl_hw_t *irq_ctrl_base = cyw43_core_num ?
+                                          &iobank0_hw->proc1_irq_ctrl : &iobank0_hw->proc0_irq_ctrl;
+        hw_set_bits(&irq_ctrl_base->intf[CYW43_PIN_WL_HOST_WAKE/8], GPIO_IRQ_LEVEL_HIGH << (4 * (CYW43_PIN_WL_HOST_WAKE & 7)));
+    }
+}
+
+void cyw43_schedule_internal_poll_dispatch(void (*func)(void)) {
+    low_prio_irq_schedule_dispatch(CYW43_DISPATCH_SLOT_CYW43, func);
+}
+
+// Prevent background processing in pensv and access by the other core
+// These methods are called in pensv context and on either core
+// They can be called recursively
+void cyw43_thread_enter(void) {
+    // Lock the other core and stop low_prio_irq running
+    recursive_mutex_enter_blocking(&cyw43_mutex);
+}
+
+#ifndef NDEBUG
+void cyw43_thread_lock_check(void) {
+    // Lock the other core and stop low_prio_irq running
+    if (recursive_mutex_enter_count(&cyw43_mutex) < 1 || recursive_mutex_owner(&cyw43_mutex) != lock_get_caller_owner_id()) {
+        panic("cyw43_thread_lock_check failed");
+    }
+}
+#endif
+
+// Re-enable background processing
+void cyw43_thread_exit(void) {
+    // Run low_prio_irq if needed
+    if (1 == recursive_mutex_enter_count(&cyw43_mutex)) {
+        // note the outer release of the mutex is not via cyw43_exit in the low_priority_irq case (it is a direct mutex exit)
+        assert(!in_low_priority_irq);
+//        if (low_priority_irq_missed) {
+//            low_priority_irq_missed = false;
+            if (low_priority_irq_dispatch_slots[CYW43_DISPATCH_SLOT_CYW43]) {
+                low_prio_irq_schedule_dispatch(CYW43_DISPATCH_SLOT_CYW43, cyw43_poll);
+            }
+//        }
+    }
+    recursive_mutex_exit(&cyw43_mutex);
+}
+
+
+static void cyw43_delay_until(absolute_time_t until) {
+    // sleep can be called in IRQs, so there's not much we can do there
+    if (__get_current_exception()) {
+        busy_wait_until(until);
+    } else {
+        sleep_until(until);
+    }
+}
+
+void cyw43_delay_ms(uint32_t ms) {
+    cyw43_delay_until(make_timeout_time_ms(ms));
+}
+
+void cyw43_delay_us(uint32_t us) {
+    cyw43_delay_until(make_timeout_time_us(us));
+}
+
+void cyw43_arch_poll() {
+    // should not be necessary
+//    if (cyw43_poll) {
+//        low_prio_irq_schedule_dispatch(CYW43_DISPATCH_SLOT_CYW43, cyw43_poll);
+//    }
+}
+
+#if !CYW43_LWIP
+static void no_lwip_fail() {
+    panic("You cannot use IP with pico_cyw43_arch_none");
+}
+void cyw43_cb_tcpip_init(cyw43_t *self, int itf) {
+}
+void cyw43_cb_tcpip_deinit(cyw43_t *self, int itf) {
+}
+void cyw43_cb_tcpip_set_link_up(cyw43_t *self, int itf) {
+    no_lwip_fail();
+}
+void cyw43_cb_tcpip_set_link_down(cyw43_t *self, int itf) {
+    no_lwip_fail();
+}
+void cyw43_cb_process_ethernet(void *cb_data, int itf, size_t len, const uint8_t *buf) {
+    no_lwip_fail();
+}
+#endif
+
+#endif
\ No newline at end of file