samples: Introduce "simple_txrx"

This introduce an example of use of Rail library in Zephyr.

This is a reboot of PR[1]. Compared to the original PR, this version:
  - remove some files imported from Simplicity Studio. Only
    radio_config.[ch] are kept.
  - drop the useless Finite State Machine

For now only two boards (based xg22 and xg24) are supported. I hope to
add support for all the Series-2 boards in the future.

Note Zephyr does not allow to host samples application in HALs. Samples
specific to one board and using non-standard APIs are not very welcomed
in the main repo. So, the Silabs downstream is probably the best (the
only) place to provide publish it.

[1]: zephyrproject-rtos/hal_silabs#49

samples/simple_txrx/CMakeLists.txt

@@ -0,0 +1,14 @@
+# Copyright (c) 2023 Silicon Laboratories Inc.
+# SPDX-License-Identifier: Zlib
+
+cmake_minimum_required(VERSION 3.20.0)
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(simple_txrx)
+
+target_include_directories(app PRIVATE
+    src/rail-configs/${CONFIG_BOARD}
+)
+target_sources(app PRIVATE
+    src/main.c
+    src/rail-configs/${CONFIG_BOARD}/rail_config.c
+)

samples/simple_txrx/boards/sltb010a.overlay

@@ -0,0 +1,8 @@
+/*
+ * Copyright (c) 2023 Silicon Laboratories Inc.
+ * SPDX-License-Identifier: Zlib
+ */
+
+&cpu0 {
+	cpu-power-states = <&pstate_em1>;
+};

samples/simple_txrx/boards/xg24_dk2601b.overlay

@@ -0,0 +1,8 @@
+/*
+ * Copyright (c) 2023 Silicon Laboratories Inc.
+ * SPDX-License-Identifier: Zlib
+ */
+
+&cpu0 {
+	cpu-power-states = <&pstate_em1>;
+};

samples/simple_txrx/prj.conf

@@ -0,0 +1,8 @@
+CONFIG_SOC_GECKO_CUSTOM_RADIO_PHY=y
+CONFIG_SHELL=y
+CONFIG_PM=y
+CONFIG_EVENTS=y
+CONFIG_LOG=y
+
+CONFIG_DEBUG_THREAD_INFO=y
+CONFIG_DEBUG=y

samples/simple_txrx/src/main.c

@@ -0,0 +1,276 @@
+/*
+ * Copyright (c) 2024 Silicon Laboratories Inc.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#include <zephyr/drivers/gpio.h>
+#include <zephyr/shell/shell.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/kernel.h>
+
+#include "rail.h"
+#include "rail_config.h"
+#include "pa_conversions_efr32.h"
+
+LOG_MODULE_REGISTER(app);
+
+#ifdef RAIL0_CHANNEL_GROUP_1_PROFILE_WISUN_OFDM
+#  if !defined(HARDWARE_BOARD_HAS_EFF)
+	BUILD_ASSERT(SL_RAIL_UTIL_PA_SELECTION_SUBGHZ == RAIL_TX_POWER_MODE_OFDM_PA,
+		     "Please use the OFDM PA settings in the sl_rail_util_pa_config.h for OFDM phys");
+#  endif
+#  if RAIL_SUPPORTS_EFF && defined(HARDWARE_BOARD_HAS_EFF)
+	BUILD_ASSERT(SL_RAIL_UTIL_PA_SELECTION_SUBGHZ >= RAIL_TX_POWER_MODE_OFDM_PA_EFF_30DBM,
+		     "Please use the OFDM PA for EFF settings in the sl_rail_util_pa_config.h for OFDM phys");
+#  endif
+#endif
+
+static const struct gpio_dt_spec sw0 = GPIO_DT_SPEC_GET(DT_ALIAS(sw0), gpios);
+static const struct gpio_dt_spec led_rx = GPIO_DT_SPEC_GET(DT_ALIAS(led0), gpios);
+#if DT_NODE_EXISTS(DT_ALIAS(led1))
+static const struct gpio_dt_spec led_tx = GPIO_DT_SPEC_GET(DT_ALIAS(led1), gpios);
+#else
+static const struct gpio_dt_spec led_tx = led_rx;
+#endif
+
+struct {
+	RAIL_Handle_t rail_handle;
+	struct k_event rx_event;
+	int channel;
+	const uint8_t *payload;
+	int payload_len;
+} app_ctx;
+
+void rx_packets(RAIL_Handle_t rail_handle)
+{
+	uint8_t rx_frame[32];
+	RAIL_RxPacketHandle_t handle;
+	RAIL_RxPacketInfo_t info;
+	RAIL_Status_t status;
+
+	for (;;) {
+		handle = RAIL_GetRxPacketInfo(rail_handle, RAIL_RX_PACKET_HANDLE_OLDEST_COMPLETE, &info);
+		if (handle == RAIL_RX_PACKET_HANDLE_INVALID) {
+			return;
+		}
+		if (info.packetBytes < sizeof(rx_frame)) {
+			RAIL_CopyRxPacket(rx_frame, &info);
+		}
+		status = RAIL_ReleaseRxPacket(rail_handle, handle);
+		if (status) {
+			LOG_ERR("RAIL_ReleaseRxPacket(): %d", status);
+		}
+		if (info.packetBytes < sizeof(rx_frame)) {
+			LOG_HEXDUMP_INF(rx_frame, info.packetBytes, "rx data:");
+		} else {
+			LOG_INF("rx: skip large packet");
+		}
+		gpio_pin_toggle_dt(&led_rx);
+	}
+}
+
+void tx_packet(RAIL_Handle_t rail_handle, int channel, const uint8_t *payload, int len)
+{
+	RAIL_Status_t status;
+	int ret;
+
+	ret = RAIL_WriteTxFifo(rail_handle, payload, len, true);
+	if (ret != len) {
+		LOG_ERR("RAIL_WriteTxFifo(): %d", ret);
+		return;
+	}
+	gpio_pin_toggle_dt(&led_tx);
+	status = RAIL_StartTx(rail_handle, channel, RAIL_TX_OPTIONS_DEFAULT, NULL);
+	if (status) {
+		LOG_ERR("RAIL_StartTx(): %d ", status);
+	}
+	LOG_HEXDUMP_INF(payload, len, "tx data:");
+}
+
+void btn_pressed(const struct device *dev, struct gpio_callback *cb, uint32_t pins)
+{
+	tx_packet(app_ctx.rail_handle, app_ctx.channel, app_ctx.payload, app_ctx.payload_len);
+}
+
+void cli_send(const struct shell *sh, size_t argc, char **argv)
+{
+	tx_packet(app_ctx.rail_handle, app_ctx.channel, app_ctx.payload, app_ctx.payload_len);
+}
+
+void rail_on_event(RAIL_Handle_t rail_handle, RAIL_Events_t events)
+{
+	RAIL_Status_t status;
+
+	if (events & RAIL_EVENTS_RX_COMPLETION ) {
+		if (events & RAIL_EVENT_RX_PACKET_RECEIVED) {
+			gpio_pin_toggle_dt(&led_rx);
+			RAIL_HoldRxPacket(rail_handle);
+			k_event_post(&app_ctx.rx_event, 1);
+		} else {
+			LOG_ERR("radio rx error: %08llx", events);
+		}
+	}
+
+	if (events & RAIL_EVENTS_TX_COMPLETION) {
+		if (!(events & RAIL_EVENT_TX_PACKET_SENT)) {
+			LOG_ERR("radio tx error: %08llx", events);
+		}
+		gpio_pin_toggle_dt(&led_tx);
+	}
+
+	if (events & RAIL_EVENTS_TXACK_COMPLETION) {
+		// TWe do not configure Tx ack. Catch the event anyway.
+		LOG_INF("received ack completion");
+	}
+
+	if (events & RAIL_EVENT_CAL_NEEDED ) {
+		status = RAIL_Calibrate(rail_handle, NULL, RAIL_CAL_ALL_PENDING);
+		if (status) {
+			LOG_ERR("RAIL_Calibrate(): %d", status);
+		}
+	}
+}
+
+void rail_on_rf_ready(RAIL_Handle_t rail_handle)
+{
+	LOG_INF("radio is ready");
+}
+
+void rail_on_channel_config_change(RAIL_Handle_t rail_handle, const RAIL_ChannelConfigEntry_t *entry)
+{
+	sl_rail_util_pa_on_channel_config_change(rail_handle, entry);
+}
+
+static RAIL_Handle_t rail_init(void)
+{
+	static uint8_t tx_fifo[256] __aligned(4);
+	RAIL_Config_t rail_config = {
+		.eventsCallback = &rail_on_event,
+	};
+	RAIL_DataConfig_t data_config = {
+		.txSource = TX_PACKET_DATA,
+		.rxSource = RX_PACKET_DATA,
+		.txMethod = PACKET_MODE,
+		.rxMethod = PACKET_MODE,
+	};
+	RAIL_StateTransitions_t transitions = {
+		.success = RAIL_RF_STATE_RX,
+		.error   = RAIL_RF_STATE_RX,
+	};
+	RAIL_Handle_t rail_handle;
+	RAIL_Status_t status;
+	int ret;
+
+	rail_handle = RAIL_Init(&rail_config, &rail_on_rf_ready);
+	if (!rail_handle) {
+		LOG_ERR("RAIL_Init() failed");
+	}
+	status = RAIL_ConfigData(rail_handle, &data_config);
+	if (status) {
+		LOG_ERR("RAIL_ConfigData(): %d", status);
+	}
+	status = RAIL_ConfigChannels(rail_handle, channelConfigs[0], &rail_on_channel_config_change);
+	if (status) {
+		LOG_ERR("RAIL_ConfigChannels(): %d", status);
+	}
+	status = RAIL_SetPtiProtocol(rail_handle, RAIL_PTI_PROTOCOL_CUSTOM);
+	if (status) {
+		LOG_ERR("RAIL_SetPtiProtocol(): %d", status);
+	}
+	status = RAIL_ConfigCal(rail_handle, RAIL_CAL_TEMP | RAIL_CAL_ONETIME);
+	if (status) {
+		LOG_ERR("RAIL_ConfigCal(): %d", status);
+	}
+	status = RAIL_ConfigEvents(rail_handle, RAIL_EVENTS_ALL,
+				   RAIL_EVENTS_RX_COMPLETION |
+				   RAIL_EVENTS_TX_COMPLETION |
+				   RAIL_EVENTS_TXACK_COMPLETION |
+				   RAIL_EVENT_CAL_NEEDED);
+	if (status) {
+		LOG_ERR("RAIL_ConfigEvents(): %d", status);
+	}
+	status = RAIL_SetTxTransitions(rail_handle, &transitions);
+	if (status) {
+		LOG_ERR("RAIL_SetTxTransitions(): %d", status);
+	}
+	status = RAIL_SetRxTransitions(rail_handle, &transitions);
+	if (status) {
+		LOG_ERR("RAIL_SetRxTransitions(): %d", status);
+	}
+	ret = RAIL_SetTxFifo(rail_handle, tx_fifo, 0, sizeof(tx_fifo));
+	if (ret != sizeof(tx_fifo)) {
+		LOG_ERR("RAIL_SetTxFifo(): %d != %d", ret, sizeof(tx_fifo));
+	}
+
+	return rail_handle;
+}
+
+static void rail_isr_installer(void)
+{
+#ifdef CONFIG_SOC_SERIES_EFR32MG24
+	IRQ_CONNECT(SYNTH_IRQn, 0, SYNTH_IRQHandler, NULL, 0);
+#else
+	IRQ_CONNECT(RDMAILBOX_IRQn, 0, RDMAILBOX_IRQHandler, NULL, 0);
+#endif
+	IRQ_CONNECT(RAC_SEQ_IRQn, 0, RAC_SEQ_IRQHandler, NULL, 0);
+	IRQ_CONNECT(RAC_RSM_IRQn, 0, RAC_RSM_IRQHandler, NULL, 0);
+	IRQ_CONNECT(PROTIMER_IRQn, 0, PROTIMER_IRQHandler, NULL, 0);
+	IRQ_CONNECT(MODEM_IRQn, 0, MODEM_IRQHandler, NULL, 0);
+	IRQ_CONNECT(FRC_IRQn, 0, FRC_IRQHandler, NULL, 0);
+	IRQ_CONNECT(BUFC_IRQn, 0, BUFC_IRQHandler, NULL, 0);
+	IRQ_CONNECT(AGC_IRQn, 0, AGC_IRQHandler, NULL, 0);
+}
+
+int main(void)
+{
+	static const uint8_t default_payload[] = {
+		0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
+		0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF
+	};
+	struct gpio_callback sw0_cb;
+	RAIL_Status_t status;
+	int ret;
+
+	k_event_init(&app_ctx.rx_event);
+	gpio_pin_configure_dt(&led_tx, GPIO_OUTPUT_INACTIVE);
+	gpio_pin_configure_dt(&led_rx, GPIO_OUTPUT_INACTIVE);
+	gpio_pin_configure_dt(&sw0, GPIO_INPUT);
+	gpio_pin_interrupt_configure_dt(&sw0, GPIO_INT_EDGE_TO_ACTIVE);
+	gpio_init_callback(&sw0_cb, btn_pressed, BIT(sw0.pin));
+	gpio_add_callback(sw0.port, &sw0_cb);
+
+	rail_isr_installer();
+	sl_rail_util_pa_init();
+	app_ctx.rail_handle = rail_init();
+	app_ctx.channel = 0;
+	app_ctx.payload = default_payload;
+	app_ctx.payload_len = sizeof(default_payload);
+
+	ret = RAIL_SetFixedLength(app_ctx.rail_handle, app_ctx.payload_len);
+	if (ret != app_ctx.payload_len) {
+		LOG_ERR("RAIL_SetFixedLength(): %d ", ret);
+	}
+	status = RAIL_StartRx(app_ctx.rail_handle, app_ctx.channel, NULL);
+	if (status) {
+		LOG_ERR("RAIL_StartRx(): %d ", status);
+	}
+
+#ifdef CONFIG_PM
+	status = RAIL_InitPowerManager();
+	if (status) {
+		LOG_ERR("RAIL_InitPowerManager(): %d", status);
+	}
+#endif
+
+	for (;;) {
+		k_event_wait(&app_ctx.rx_event, 0xFFFFFFFF, true, K_FOREVER);
+		rx_packets(app_ctx.rail_handle);
+	}
+
+	return 0;
+}
+
+SHELL_STATIC_SUBCMD_SET_CREATE(radio_cmds,
+	SHELL_CMD_ARG(send, NULL, "Send a packet", cli_send, 1, 0),
+	SHELL_SUBCMD_SET_END
+);
+SHELL_CMD_ARG_REGISTER(radio, &radio_cmds, "Radio control", NULL, 2, 0);

samples/simple_txrx/src/rail-configs/sltb010a/radio_settings.radioconf

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<multi_phy_configuration part_family="lynx" part_revision="A0" rail_adapter_version="rail_api_2.x" status_code="0" xsd_version="0.0.20">
+  <base_channel_configurations>
+    <base_channel_configuration name="Protocol Configuration" profile="Base">
+      <channel_config_entries>
+        <channel_config_entry name="Channel Group 1">
+          <channel_number_start>0</channel_number_start>
+          <channel_number_end>20</channel_number_end>
+          <physical_channel_offset>SAME_AS_FIRST_CHANNEL</physical_channel_offset>
+          <max_power>RAIL_TX_POWER_MAX</max_power>
+          <metadata>{"selectedPhy":"PHY_Datasheet_2450M_2GFSK_1Mbps_500K"}</metadata>
+        </channel_config_entry>
+      </channel_config_entries>
+      <metadata>{"selectedPhy":"PHY_Datasheet_2450M_2GFSK_1Mbps_500K"}</metadata>
+      <phy name="PHY_Datasheet_2450M_2GFSK_1Mbps_500K"/>
+    </base_channel_configuration>
+  </base_channel_configurations>
+</multi_phy_configuration>