fix: idk

.vscode/settings.json

@@ -38,6 +38,73 @@
         "vector": "c",
         "memory_resource": "c",
         "__config": "c",
-        "string": "c"
-    }
+        "string": "c",
+        "atomic": "c",
+        "__bit_reference": "c",
+        "err.h": "c",
+        "httpd.h": "c",
+        "random": "c",
+        "limits": "c",
+        "tuple": "c",
+        "init.h": "c",
+        "hw_i2c.h": "c",
+        "chrono": "c",
+        "stop_token": "c",
+        "__locale": "c",
+        "stdint.h": "c",
+        "ch32v208_eth.h": "c",
+        "bit": "c",
+        "any": "c",
+        "array": "c",
+        "hash_map": "c",
+        "strstream": "c",
+        "charconv": "c",
+        "cmath": "c",
+        "codecvt": "c",
+        "complex": "c",
+        "concepts": "c",
+        "condition_variable": "c",
+        "coroutine": "c",
+        "cstddef": "c",
+        "unordered_map": "c",
+        "unordered_set": "c",
+        "exception": "c",
+        "memory": "c",
+        "numeric": "c",
+        "optional": "c",
+        "ratio": "c",
+        "string_view": "c",
+        "system_error": "c",
+        "type_traits": "c",
+        "algorithm": "c",
+        "iomanip": "c",
+        "mutex": "c",
+        "ostream": "c",
+        "semaphore": "c",
+        "shared_mutex": "c",
+        "span": "c",
+        "stacktrace": "c",
+        "text_encoding": "c",
+        "thread": "c",
+        "typeindex": "c",
+        "typeinfo": "c",
+        "utility": "c",
+        "valarray": "c",
+        "__assert": "c",
+        "__split_buffer": "c",
+        "ios": "c",
+        "map": "c",
+        "new": "c",
+        "queue": "c",
+        "set": "c",
+        "stack": "c",
+        "stdexcept": "c",
+        "__node_handle": "c",
+        "execution": "c",
+        "numbers": "c",
+        "print": "c",
+        "ha_mqtt.h": "c",
+        "ethernetif.h": "c"
+    },
+    "cmake.sourceDirectory": "/home/mira/src/embedded/ch32v208_sens/lwip"
 }

Makefile

@@ -21,11 +21,12 @@ LWIP_C_FILES += $(COREFILES)
 LWIP_C_FILES += $(CORE4FILES)
 LWIP_C_FILES += $(NETIFFILES)
 LWIP_C_FILES += $(HTTPFILES)
+LWIP_C_FILES += $(MQTTFILES)
 
 LWIP_C_FILES_WITH_PATH := $(LWIP_C_FILES)
-LWIP_PORT_FILES := $(wildcard $(PORT_DIR)/*.c)
+LWIP_PORT_FILES := $(wildcard $(PORT_DIR)/*.c $(PORT_DIR)/arch/*.c)
 
-INCLUDE_DIRS ?= \
+INCLUDE_DIRS += \
 	-I./inc \
 	-I$(LWIP_DIR)/src/include \
 	-I$(PORT_DIR)

README.md

@@ -0,0 +1,36 @@
+# lwIP Ethernet Driver for CH32V208
+
+This is a simple ethernetif.c driver to get lwIP working on the WCH CH32V208 MCU using the ch32fun lib.  
+It uses the chip's internal 10Mbps Ethernet MAC. The MAC address is pulled from the chip's 6-byte unique ID.
+
+The provided main.c is an example that starts up, gets an IP address via DHCP, and runs a small HTTP server.
+
+## Usage
+
+1.  Initialize lwIP and add the network interface.
+2.  Poll the driver and service lwIP's timers in your main loop.
+
+```c
+netif_add(&g_netif, &ipaddr, &netmask, &gw, NULL, &ethernetif_init, &ethernet_input);
+netif_set_default(&g_netif);
+netif_set_up(&g_netif);
+dhcp_start(&g_netif);
+
+while (1) {
+  // poll for incoming packets
+  ethernetif_input(&g_netif);
+
+  // handle lwIP timers (for TCP, DHCP, etc.)
+  sys_check_timeouts();
+
+  // poll link for link up/down cb
+  ethernetif_link_poll(&g_netif);
+}
+```
+
+## Impl note
+
+This driver is kinda functional but not optimized
+
+-   **Packet RX:** ~~This is done by polling~~ RXIF works now. You must call `ethernetif_input()` continuously in your main loop to check for and process incoming packets
+-   **Packet TX:** TX isn't exactly typical DMA? The CPU has to copy the packet into a single transmit buffer and then manually start the transmission. An ISR will signal when the buffer is free to send the next packet

funconfig.h

@@ -1,9 +1,9 @@
 #ifndef _FUNCONFIG_H
 #define _FUNCONFIG_H
 
-#define FUNCONF_USE_HSE 1
+// #define FUNCONF_USE_HSE 1
 #define FUNCONF_SYSTEM_CORE_CLOCK 120000000
-#define FUNCONF_PLL_MULTIPLIER 15
+// #define FUNCONF_PLL_MULTIPLIER 15
 #define FUNCONF_SYSTICK_USE_HCLK 1
 
 #endif

ha_mqtt.c

@@ -0,0 +1,199 @@
+// ha_mqtt.c
+
+#include "ha_mqtt.h"
+
+#include <stdio.h>
+#include <string.h>
+
+#include "lwip/apps/mqtt.h"
+#include "lwip/ip4_addr.h"
+#include "lwip/netif.h"
+#include "systick.h"
+
+// config
+#define MQTT_BROKER_IP_A 192
+#define MQTT_BROKER_IP_B 168
+#define MQTT_BROKER_IP_C 102
+#define MQTT_BROKER_IP_D 1
+#define MQTT_BROKER_PORT 1883
+#define MQTT_CLIENT_ID "gxht30_sensor_node"
+#define MQTT_RECONNECT_INTERVAL_MS 5000
+
+#define DEVICE_UNIQUE_ID "gxht30_board_01"
+#define DEVICE_NAME "Office Climate Sensor"
+#define DEVICE_MANUFACTURER "me"
+#define DEVICE_MODEL "GXHT30-ETH-v1"
+
+// home assistant topics
+#define HA_DISCOVERY_PREFIX "homeassistant"
+
+#define TEMP_UNIQUE_ID DEVICE_UNIQUE_ID "_temperature"
+#define TEMP_CONFIG_TOPIC \
+  HA_DISCOVERY_PREFIX "/sensor/" TEMP_UNIQUE_ID "/config"
+#define TEMP_STATE_TOPIC "devices/" DEVICE_UNIQUE_ID "/temperature/state"
+#define TEMP_NAME "Temperature"
+
+#define HUM_UNIQUE_ID DEVICE_UNIQUE_ID "_humidity"
+#define HUM_CONFIG_TOPIC HA_DISCOVERY_PREFIX "/sensor/" HUM_UNIQUE_ID "/config"
+#define HUM_STATE_TOPIC "devices/" DEVICE_UNIQUE_ID "/humidity/state"
+#define HUM_NAME "Humidity"
+
+#define MQTT_RECONNECT_INTERVAL_MS 5000
+
+static mqtt_client_t* s_mqtt_client;
+static ip_addr_t s_mqtt_broker_ip;
+static uint8_t s_mqtt_connected = 0;
+static uint32_t s_last_mqtt_retry_time = 0;
+
+extern struct netif g_netif;
+
+static void publish_ha_discovery_configs(mqtt_client_t* client);
+static void mqtt_pub_request_cb(void* arg, err_t err);
+static void mqtt_connection_cb(mqtt_client_t* client, void* arg,
+                               mqtt_connection_status_t status);
+static void publish_sensor_value(const char* topic, int32_t value_x100);
+
+// public fns
+
+void ha_mqtt_init(void) {
+  s_mqtt_client = mqtt_client_new();
+  if (s_mqtt_client == NULL) {
+    printf("error: failed to create mqtt client\n");
+    return;
+  }
+
+  IP4_ADDR(&s_mqtt_broker_ip, MQTT_BROKER_IP_A, MQTT_BROKER_IP_B,
+           MQTT_BROKER_IP_C, MQTT_BROKER_IP_D);
+
+  ha_mqtt_check_and_reconnect();
+}
+
+void ha_mqtt_publish_sensor_data(int32_t temp_x100, int32_t hum_x100) {
+  if (!s_mqtt_connected) {
+    return;
+  }
+  publish_sensor_value(TEMP_STATE_TOPIC, temp_x100);
+  publish_sensor_value(HUM_STATE_TOPIC, hum_x100);
+}
+
+void ha_mqtt_check_and_reconnect(void) {
+  if (s_mqtt_connected || !netif_is_up(&g_netif) ||
+      !netif_is_link_up(&g_netif) || netif_ip4_addr(&g_netif)->addr == 0) {
+    return;
+  }
+
+  if (millis() - s_last_mqtt_retry_time > MQTT_RECONNECT_INTERVAL_MS) {
+    printf("attempting to connect to mqtt broker\n");
+
+    const struct mqtt_connect_client_info_t client_info = {
+        .client_id = MQTT_CLIENT_ID,
+        .keep_alive = 60,
+        // .client_user = "user", // authentication
+        // .client_pass = "pass",
+    };
+
+    err_t err =
+        mqtt_client_connect(s_mqtt_client, &s_mqtt_broker_ip, MQTT_BROKER_PORT,
+                            mqtt_connection_cb, NULL, &client_info);
+
+    if (err != ERR_OK) {
+      printf("mqtt connect failed with immediate error: %d\n", err);
+    }
+    s_last_mqtt_retry_time = millis();
+  }
+}
+
+uint8_t ha_mqtt_is_connected(void) { return s_mqtt_connected; }
+
+// static fns
+
+/**
+ * @brief Publishes a sensor value after formatting it from a fixed-point
+ * int
+ * @param topic The MQTT topic to publish to.
+ * @param value_x100 The sensor value, scaled by 100.
+ */
+static void publish_sensor_value(const char* topic, int32_t value_x100) {
+  char payload_buf[16];
+
+  // format the fixed-point value (e.g., 2345) into a decimal string ("23.45")
+  int32_t val_int = value_x100 / 100;
+  int32_t val_frac = value_x100 % 100;
+  if (val_frac < 0) {
+    val_frac = -val_frac;
+  }
+  snprintf(payload_buf, sizeof(payload_buf), "%ld.%02ld", val_int, val_frac);
+
+  err_t err = mqtt_publish(s_mqtt_client, topic, payload_buf,
+                           strlen(payload_buf), 1, 0, NULL, NULL);
+
+  if (err != ERR_OK) {
+    printf("failed to publish to topic %s: %d\n", topic, err);
+  }
+}
+
+static void publish_ha_discovery_configs(mqtt_client_t* client) {
+  char payload[512];
+  err_t err;
+
+  // publish temperature sensor config
+  snprintf(
+      payload, sizeof(payload),
+      "{"
+      "\"name\":\"%s\",\"unique_id\":\"%s\",\"stat_t\":\"%s\","
+      "\"dev_cla\":\"temperature\",\"unit_of_meas\":\"°C\","
+      "\"val_tpl\":\"{{ value|float(2) }}\","
+      "\"dev\":{\"ids\":[\"%s\"],\"name\":\"%s\",\"mf\":\"%s\",\"mdl\":\"%s\"}"
+      "}",
+      TEMP_NAME, TEMP_UNIQUE_ID, TEMP_STATE_TOPIC, DEVICE_UNIQUE_ID,
+      DEVICE_NAME, DEVICE_MANUFACTURER, DEVICE_MODEL);
+
+  printf("publishing ha discovery for temperature...\n");
+  err = mqtt_publish(client, TEMP_CONFIG_TOPIC, payload, strlen(payload), 1, 1,
+                     mqtt_pub_request_cb, NULL);
+  if (err != ERR_OK) {
+    printf("failed to publish temp config: %d\n", err);
+  }
+
+  // publish humidity sensor config
+  snprintf(
+      payload, sizeof(payload),
+      "{"
+      "\"name\":\"%s\",\"unique_id\":\"%s\",\"stat_t\":\"%s\","
+      "\"dev_cla\":\"humidity\",\"unit_of_meas\":\"%%\","
+      "\"val_tpl\":\"{{ value|float(2) }}\","
+      "\"dev\":{\"ids\":[\"%s\"],\"name\":\"%s\",\"mf\":\"%s\",\"mdl\":\"%s\"}"
+      "}",
+      HUM_NAME, HUM_UNIQUE_ID, HUM_STATE_TOPIC, DEVICE_UNIQUE_ID, DEVICE_NAME,
+      DEVICE_MANUFACTURER, DEVICE_MODEL);
+
+  printf("publishing ha discovery for humidity...\n");
+  err = mqtt_publish(client, HUM_CONFIG_TOPIC, payload, strlen(payload), 1, 1,
+                     mqtt_pub_request_cb, NULL);
+  if (err != ERR_OK) {
+    printf("failed to publish hum config: %d\n", err);
+  }
+}
+
+static void mqtt_pub_request_cb(void* arg, err_t err) {
+  (void)arg;
+
+  if (err != ERR_OK) {
+    printf("mqtt publish failed with error: %d\n", err);
+  }
+}
+
+static void mqtt_connection_cb(mqtt_client_t* client, void* arg,
+                               mqtt_connection_status_t status) {
+  (void)arg;
+
+  if (status == MQTT_CONNECT_ACCEPTED) {
+    printf("mqtt connection successful\n");
+    s_mqtt_connected = 1;
+    // on connect, publish the discovery configuration messages
+    publish_ha_discovery_configs(client);
+  } else {
+    printf("mqtt connection failed, status: %d. will retry.\n", status);
+    s_mqtt_connected = 0;
+  }
+}

inc/gxht30_hw_i2c.h

@@ -0,0 +1,159 @@
+#ifndef _GXHT30_HW_I2C_H
+#define _GXHT30_HW_I2C_H
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "hw_i2c.h"
+
+// GXHT30 I2C addresses
+#define GXHT30_I2C_ADDR_DEFAULT 0x44
+#define GXHT30_I2C_ADDR_ALT 0x45
+
+// GXHT30 cmds
+#define GXHT30_CMD_MEAS_MSB 0x2C
+#define GXHT30_CMD_MEAS_LSB 0x06
+#define GXHT30_CMD_SOFT_RESET_MSB 0x30
+#define GXHT30_CMD_SOFT_RESET_LSB 0xA2
+#define GXHT30_CMD_HEATER_ON_MSB 0x30
+#define GXHT30_CMD_HEATER_ON_LSB 0x6D
+#define GXHT30_CMD_HEATER_OFF_MSB 0x30
+#define GXHT30_CMD_HEATER_OFF_LSB 0x66
+#define GXHT30_CMD_STATUS_MSB 0xF3
+#define GXHT30_CMD_STATUS_LSB 0x2D
+#define GXHT30_CMD_CLEAR_STATUS_MSB 0x30
+#define GXHT30_CMD_CLEAR_STATUS_LSB 0x41
+
+// conversion constants
+#define GXHT30_TEMP_MULTIPLIER 2670
+#define GXHT30_TEMP_OFFSET 45000000L
+#define GXHT30_HUM_MULTIPLIER 1526
+#define GXHT30_SCALE_DIVISOR 10000
+
+typedef struct {
+  int32_t temperature_x100;  // Temperature in hundredths of a degree C
+  int32_t humidity_x100;     // Humidity in hundredths of a percent RH
+  uint8_t error;             // Last error code
+} GXHT30_Data;
+
+typedef struct {
+  uint8_t alert_pending;      // Bit 15: Alert status
+  uint8_t heater_on;          // Bit 13: Heater status
+  uint8_t humidity_alert;     // Bit 11: Humidity tracking alert
+  uint8_t temperature_alert;  // Bit 10: Temperature tracking alert
+  uint8_t reset_detected;     // Bit 4: System reset detected
+  uint8_t command_status;     // Bit 1: Last command execution status
+  uint8_t crc_status;         // Bit 0: Write data CRC checksum status
+  uint16_t raw_status;        // Raw 16-bit status value
+} GXHT30_Status;
+
+enum GXHT30_Error {
+  GXHT30_OK = 0,
+  GXHT30_ERR_TIMEOUT,
+  GXHT30_ERR_CRC,
+  GXHT30_ERR_I2C
+};
+
+static inline bool gxht30_crc8_check(uint8_t msb, uint8_t lsb, uint8_t crc) {
+  uint8_t calc_crc = 0xFF;
+  uint8_t data[2] = {msb, lsb};
+
+  for (uint8_t byte = 0; byte < 2; byte++) {
+    calc_crc ^= data[byte];
+    for (uint8_t i = 0; i < 8; i++) {
+      calc_crc = (calc_crc & 0x80) ? (calc_crc << 1) ^ 0x31 : (calc_crc << 1);
+    }
+  }
+
+  return calc_crc == crc;
+}
+
+static inline uint8_t gxht30_send_command(uint8_t addr, uint8_t cmd_msb,
+                                          uint8_t cmd_lsb) {
+  uint8_t cmd[2] = {cmd_msb, cmd_lsb};
+  uint8_t err = i2c_write(addr, cmd, 2);
+
+  return (err == I2C_OK) ? GXHT30_OK : GXHT30_ERR_I2C;
+}
+
+static inline uint8_t gxht30_read_data(uint8_t addr, GXHT30_Data* data) {
+  uint8_t cmd[2] = {GXHT30_CMD_MEAS_MSB, GXHT30_CMD_MEAS_LSB};
+  uint8_t rx_data[6];
+  uint8_t err;
+
+  // send measurement command and read
+  if ((err = i2c_write_read(addr, cmd, 2, rx_data, 6)) != I2C_OK) {
+    data->error = GXHT30_ERR_I2C;
+    return GXHT30_ERR_I2C;
+  }
+
+  // verify CRC for both temp and humidity
+  if (!gxht30_crc8_check(rx_data[0], rx_data[1], rx_data[2]) ||
+      !gxht30_crc8_check(rx_data[3], rx_data[4], rx_data[5])) {
+    data->error = GXHT30_ERR_CRC;
+    return GXHT30_ERR_CRC;
+  }
+
+  // calc the values
+  uint16_t temp_raw = (rx_data[0] << 8) | rx_data[1];
+  uint16_t hum_raw = (rx_data[3] << 8) | rx_data[4];
+
+  data->temperature_x100 =
+      (((int64_t)temp_raw * GXHT30_TEMP_MULTIPLIER) - GXHT30_TEMP_OFFSET) /
+      GXHT30_SCALE_DIVISOR;
+  data->humidity_x100 =
+      ((int64_t)hum_raw * GXHT30_HUM_MULTIPLIER) / GXHT30_SCALE_DIVISOR;
+  data->error = GXHT30_OK;
+
+  return GXHT30_OK;
+}
+
+static inline uint8_t gxht30_read_status(uint8_t addr, GXHT30_Status* status) {
+  uint8_t cmd[2] = {GXHT30_CMD_STATUS_MSB, GXHT30_CMD_STATUS_LSB};
+  uint8_t rx_data[3];
+  uint8_t err;
+
+  if ((err = i2c_write_read(addr, cmd, 2, rx_data, 3)) != I2C_OK) {
+    return GXHT30_ERR_I2C;
+  }
+
+  // verify CRC
+  if (!gxht30_crc8_check(rx_data[0], rx_data[1], rx_data[2])) {
+    return GXHT30_ERR_CRC;
+  }
+
+  // parse status register
+  uint16_t raw = (rx_data[0] << 8) | rx_data[1];
+  status->raw_status = raw;
+  status->alert_pending = (raw >> 15) & 0x01;
+  status->heater_on = (raw >> 13) & 0x01;
+  status->humidity_alert = (raw >> 11) & 0x01;
+  status->temperature_alert = (raw >> 10) & 0x01;
+  status->reset_detected = (raw >> 4) & 0x01;
+  status->command_status = (raw >> 1) & 0x01;
+  status->crc_status = raw & 0x01;
+
+  return GXHT30_OK;
+}
+
+static inline uint8_t gxht30_soft_reset(uint8_t addr) {
+  return gxht30_send_command(addr, GXHT30_CMD_SOFT_RESET_MSB,
+                             GXHT30_CMD_SOFT_RESET_LSB);
+}
+
+static inline uint8_t gxht30_heater_on(uint8_t addr) {
+  return gxht30_send_command(addr, GXHT30_CMD_HEATER_ON_MSB,
+                             GXHT30_CMD_HEATER_ON_LSB);
+}
+
+static inline uint8_t gxht30_heater_off(uint8_t addr) {
+  return gxht30_send_command(addr, GXHT30_CMD_HEATER_OFF_MSB,
+                             GXHT30_CMD_HEATER_OFF_LSB);
+}
+
+static inline uint8_t gxht30_clear_status(uint8_t addr) {
+  return gxht30_send_command(addr, GXHT30_CMD_CLEAR_STATUS_MSB,
+                             GXHT30_CMD_CLEAR_STATUS_LSB);
+}
+
+#endif  // _GXHT30_HW_I2C_H

inc/ha_mqtt.h

@@ -0,0 +1,13 @@
+// ha_mqtt.h
+
+#ifndef HA_MQTT_H
+#define HA_MQTT_H
+
+#include <stdint.h>
+
+void ha_mqtt_init(void);
+void ha_mqtt_publish_sensor_data(int32_t temp_x100, int32_t hum_x100);
+void ha_mqtt_check_and_reconnect(void);
+uint8_t ha_mqtt_is_connected(void);
+
+#endif  // HA_MQTT_H

inc/hw_i2c.h

@@ -0,0 +1,181 @@
+#ifndef _HW_I2C_H
+#define _HW_I2C_H
+
+#include <stdint.h>
+
+#include "ch32fun.h"
+#include "ch32v20xhw.h"
+
+// config
+#define I2C_CLKRATE 400000
+#define I2C_PRERATE 2000000
+#define I2C_TIMEOUT_MAX 250000
+
+#define I2C_DIRECTION_TX 0
+#define I2C_DIRECTION_RX 1
+
+enum I2C_Error { I2C_OK = 0, I2C_ERR_TIMEOUT, I2C_ERR_BUSY, I2C_ERR_NACK };
+
+static inline uint8_t i2c_check_event(uint32_t event_mask) {
+  uint32_t status = I2C1->STAR1 | (I2C1->STAR2 << 16);
+  return (status & event_mask) == event_mask;
+}
+
+static inline uint8_t i2c_wait_event(uint32_t event_mask) {
+  int32_t timeout = I2C_TIMEOUT_MAX;
+  while (!i2c_check_event(event_mask) && (timeout-- > 0));
+  return timeout > 0 ? I2C_OK : I2C_ERR_TIMEOUT;
+}
+
+static inline uint8_t i2c_wait_flag(uint32_t flag) {
+  int32_t timeout = I2C_TIMEOUT_MAX;
+  while (!(I2C1->STAR1 & flag) && (timeout-- > 0));
+  return timeout > 0 ? I2C_OK : I2C_ERR_TIMEOUT;
+}
+
+static inline uint8_t i2c_start(uint8_t addr, uint8_t direction) {
+  // wait until bus is not busy
+  int32_t timeout = I2C_TIMEOUT_MAX;
+  while ((I2C1->STAR2 & I2C_STAR2_BUSY) && (timeout-- > 0));
+  if (timeout <= 0) return I2C_ERR_TIMEOUT;
+
+  // gen START
+  I2C1->CTLR1 |= I2C_CTLR1_START;
+  if (i2c_wait_event(I2C_EVENT_MASTER_MODE_SELECT) != I2C_OK)
+    return I2C_ERR_TIMEOUT;
+
+  // send address
+  I2C1->DATAR = (addr << 1) | direction;
+
+  uint32_t event = (direction == I2C_DIRECTION_TX)
+                       ? I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED
+                       : I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED;
+
+  return i2c_wait_event(event);
+}
+
+static inline void i2c_stop(void) { I2C1->CTLR1 |= I2C_CTLR1_STOP; }
+
+static inline uint8_t i2c_write_byte(uint8_t data) {
+  I2C1->DATAR = data;
+  return i2c_wait_flag(I2C_STAR1_TXE);
+}
+
+static inline uint8_t i2c_write(uint8_t addr, const uint8_t* data,
+                                uint8_t length) {
+  uint8_t err;
+
+  if ((err = i2c_start(addr, I2C_DIRECTION_TX)) != I2C_OK) return err;
+
+  for (uint8_t i = 0; i < length; i++) {
+    if ((err = i2c_write_byte(data[i])) != I2C_OK) return err;
+  }
+
+  if (i2c_wait_event(I2C_EVENT_MASTER_BYTE_TRANSMITTED) != I2C_OK)
+    return I2C_ERR_TIMEOUT;
+
+  i2c_stop();
+  return I2C_OK;
+}
+
+static inline uint8_t i2c_read(uint8_t addr, uint8_t* buffer, uint8_t length) {
+  uint8_t err;
+
+  if ((err = i2c_start(addr, I2C_DIRECTION_RX)) != I2C_OK) return err;
+
+  for (uint8_t i = 0; i < length; i++) {
+    if (i == length - 1) {
+      I2C1->CTLR1 &= ~I2C_CTLR1_ACK;  // NACK last byte
+    }
+
+    if (i2c_wait_flag(I2C_STAR1_RXNE) != I2C_OK) {
+      I2C1->CTLR1 |= I2C_CTLR1_ACK;
+      return I2C_ERR_TIMEOUT;
+    }
+
+    buffer[i] = I2C1->DATAR;
+  }
+
+  I2C1->CTLR1 |= I2C_CTLR1_ACK;  // re-enable ACK
+  i2c_stop();
+  return I2C_OK;
+}
+
+static inline uint8_t i2c_write_read(uint8_t addr, const uint8_t* tx_data,
+                                     uint8_t tx_len, uint8_t* rx_data,
+                                     uint8_t rx_len) {
+  uint8_t err;
+
+  // Write phase
+  if ((err = i2c_start(addr, I2C_DIRECTION_TX)) != I2C_OK) return err;
+
+  for (uint8_t i = 0; i < tx_len; i++) {
+    if ((err = i2c_write_byte(tx_data[i])) != I2C_OK) return err;
+  }
+
+  if (i2c_wait_event(I2C_EVENT_MASTER_BYTE_TRANSMITTED) != I2C_OK)
+    return I2C_ERR_TIMEOUT;
+
+  // repeated START for read phase
+  I2C1->CTLR1 |= I2C_CTLR1_START;
+  if (i2c_wait_event(I2C_EVENT_MASTER_MODE_SELECT) != I2C_OK)
+    return I2C_ERR_TIMEOUT;
+
+  I2C1->DATAR = (addr << 1) | I2C_DIRECTION_RX;
+  if (i2c_wait_event(I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED) != I2C_OK)
+    return I2C_ERR_TIMEOUT;
+
+  // read phase
+  for (uint8_t i = 0; i < rx_len; i++) {
+    if (i == rx_len - 1) {
+      I2C1->CTLR1 &= ~I2C_CTLR1_ACK;  // NACK last byte
+    }
+
+    if (i2c_wait_flag(I2C_STAR1_RXNE) != I2C_OK) {
+      I2C1->CTLR1 |= I2C_CTLR1_ACK;
+      return I2C_ERR_TIMEOUT;
+    }
+
+    rx_data[i] = I2C1->DATAR;
+  }
+
+  I2C1->CTLR1 |= I2C_CTLR1_ACK;  // re-enable ACK
+  i2c_stop();
+  return I2C_OK;
+}
+
+static inline void i2c_init(void) {
+  uint16_t tempreg;
+
+  RCC->APB2PCENR |= RCC_APB2Periph_GPIOB | RCC_APB2Periph_AFIO;
+  RCC->APB1PCENR |= RCC_APB1Periph_I2C1;
+
+  AFIO->PCFR1 |= AFIO_PCFR1_I2C1_REMAP;  // I2C1_RM: 1
+
+  // PB8 (SCL) and PB9 (SDA)
+  funPinMode(PB8, GPIO_CFGLR_OUT_10Mhz_AF_OD);
+  funPinMode(PB9, GPIO_CFGLR_OUT_10Mhz_AF_OD);
+
+  // Reset I2C1 to init all regs
+  RCC->APB1PRSTR |= RCC_APB1Periph_I2C1;
+  RCC->APB1PRSTR &= ~RCC_APB1Periph_I2C1;
+
+  I2C1->CTLR1 |= I2C_CTLR1_SWRST;
+  I2C1->CTLR1 &= ~I2C_CTLR1_SWRST;
+
+  // set I2C freq
+  tempreg = I2C1->CTLR2;
+  tempreg &= ~I2C_CTLR2_FREQ;
+  tempreg |= (FUNCONF_SYSTEM_CORE_CLOCK / I2C_PRERATE) & I2C_CTLR2_FREQ;
+  I2C1->CTLR2 = tempreg;
+
+  // Fast Mode 400kHz
+  tempreg = (FUNCONF_SYSTEM_CORE_CLOCK / (3 * I2C_CLKRATE)) & I2C_CKCFGR_CCR;
+  tempreg |= I2C_CKCFGR_FS;
+  I2C1->CKCFGR = tempreg;
+
+  // en I2C and ACK
+  I2C1->CTLR1 |= I2C_CTLR1_PE | I2C_CTLR1_ACK;
+}
+
+#endif  // _HW_I2C_H

main.c

@@ -3,6 +3,9 @@
 #include "ch32fun.h"
 #include "ch32v20xhw.h"
 #include "ethernetif.h"
+#include "gxht30_hw_i2c.h"
+#include "ha_mqtt.h"
+#include "hw_i2c.h"
 #include "lwip/apps/httpd.h"
 #include "lwip/dhcp.h"
 #include "lwip/init.h"
@@ -17,7 +20,7 @@
 #define HSE_STARTUP_TIMEOUT 10000
 #define PLL_LOCK_TIMEOUT 10000
 #define LED_TOGGLE_INTERVAL_MS 500
-#define LINK_POLL_INTERVAL_MS 500
+#define LINK_POLL_INTERVAL_MS 100
 
 #define RCC_PREDIV1_OFFSET 0
 #define HSE_CLOCK_MHZ 32
@@ -25,49 +28,68 @@
 #define PLL_MULTIPLIER 15
 
 #define STATS_PRINT_INTERVAL_MS 10000
+#define SENSOR_READ_INTERVAL_MS 60000
 
 struct netif g_netif;
 static volatile int g_httpd_is_initialized = 0;
 
-int clock_init(void);
 void led_init(void);
 void lwip_stack_init(void);
 
-int clock_init(void) {
-  RCC->INTR = 0x009f0000;
-  RCC->CTLR &= ~(RCC_HSE_ON | RCC_PLLON);
-  RCC->CFGR0 = 0x00000000;
+static void set_sysclk_to_120mhz_from_hse(void) {
+  uint32_t startup_counter = 0;
 
-  RCC->CTLR |= RCC_HSE_ON;
-  for (int timeout = HSE_STARTUP_TIMEOUT; timeout > 0; timeout--) {
-    if (RCC->CTLR & RCC_HSERDY) break;
-    if (timeout == 1) {
-      printf("Error: HSE failed to start\n");
-      return -1;
+  RCC->INTR = 0x009F0000;  // clear PLL, CSSC, HSE, HSI and LSI ready flags.
+  // switch processor back to HSI so we don't eat dirt.
+  RCC->CFGR0 = 0;
+  // disable PLL so we can play with it.
+  RCC->CTLR &= ~RCC_PLLON;
+  // not sure why, need to reset here, otherwise PLLXTPRE is set.
+  RCC->CFGR0 = RCC_PLLSRC;
+
+  // enable HSE
+  RCC->CTLR |= RCC_HSEON;
+
+  do {
+    startup_counter++;
+  } while (!(RCC->CTLR & RCC_HSERDY) &&
+           (startup_counter < HSE_STARTUP_TIMEOUT));
+
+  if (RCC->CTLR & RCC_HSERDY) {
+    /*
+     * HCLK (AHB)  = SYSCLK / 2
+     * PCLK2 (APB2) = HCLK / 1
+     * PCLK1 (APB1) = HCLK / 2
+     * USB Clock = PLLCLK / 5 (to get 48MHz for USB)
+     */
+    RCC->CFGR0 |=
+        RCC_HPRE_DIV2 | RCC_PPRE2_DIV1 | RCC_PPRE1_DIV2 | RCC_USBPRE_DIV5;
+
+    /*
+     * When RCC_USBPRE is 3 it changes HPE div to /2 instead of /4, so:
+     * PLL Source: HSE
+     * HSE Divider for PLL: /2
+     * PLL Multiplier: x15
+     * PLL Clock = (32MHz / 2) * 15 = 240 MHz
+     */
+    uint32_t pll_config = RCC_PLLSRC_HSE | RCC_PLLXTPRE_HSE | RCC_PLLMULL15;
+    RCC->CFGR0 =
+        (RCC->CFGR0 & ~(RCC_PLLSRC | RCC_PLLXTPRE | RCC_PLLMULL)) | pll_config;
+
+    RCC->CTLR |= RCC_PLLON;
+
+    // wait for pll to lock
+    while (!(RCC->CTLR & RCC_PLLRDY)) {
     }
-  }
 
-  RCC->CFGR0 |= (uint32_t)RCC_PPRE1_DIV2;
-  RCC->CFGR2 = (PREDIV1_DIVISOR - 1);
-  RCC->CFGR0 |= RCC_PLLSource_HSE_Div1 | RCC_PLLMul_15;
+    // PLL as the system clock src
+    RCC->CFGR0 = (RCC->CFGR0 & ~RCC_SW) | RCC_SW_PLL;
 
-  RCC->CTLR |= RCC_PLLON;
-  printf("Main PLL en. Waiting for lock...\n");
-  for (int timeout = PLL_LOCK_TIMEOUT; timeout > 0; timeout--) {
-    if (RCC->CTLR & RCC_PLLRDY) break;
-    if (timeout == 1) {
-      printf("Error: Main PLL lock failed\n");
-      return -1;
+    while ((RCC->CFGR0 & RCC_SWS) != RCC_SWS_PLL) {
     }
+  } else {
+    printf("HSE failed to start\n");
   }
-  printf("Main PLL Locked\n");
-
-  RCC->CFGR0 = (RCC->CFGR0 & ~RCC_SW) | RCC_SW_PLL;
-  while ((RCC->CFGR0 & RCC_SWS) != RCC_SWS_PLL);
-
-  printf("System clock set to %dMHz.\n",
-         (HSE_CLOCK_MHZ / PREDIV1_DIVISOR) * PLL_MULTIPLIER);
-  return 0;
 }
 
 void led_init(void) {
@@ -159,15 +181,17 @@ void ethernetif_print_stats(void) {
 
 int main() {
   SystemInit();
-
-  if (clock_init() != 0) {
-    // eating dirt?
-    while (1);
-  }
+  set_sysclk_to_120mhz_from_hse();
 
   systick_init();
   led_init();
   lwip_stack_init();
+  i2c_init();
+
+  gxht30_soft_reset(GXHT30_I2C_ADDR_DEFAULT);
+  Delay_Ms(10);
+
+  ha_mqtt_init();
 
   uint32_t last_led_toggle_time = 0;
   uint32_t last_link_poll_time = 0;
@@ -176,6 +200,13 @@ int main() {
 #endif
   int led_state = 0;
 
+  uint32_t last_sensor_read_time = 0;
+  uint32_t last_status_read_time = 0;
+
+  GXHT30_Data sensor_data = {0};
+
+  printf("System initialized. Main loop starting.\n");
+
   while (1) {
     ethernetif_input(&g_netif);
     sys_check_timeouts();
@@ -192,15 +223,39 @@ int main() {
     }
 #endif
 
-    uint32_t now = millis();
-    if (now - last_led_toggle_time > LED_TOGGLE_INTERVAL_MS) {
-      if (led_state) {
-        GPIOA->BSHR = (1 << LED1_PIN);
+    ha_mqtt_check_and_reconnect();
+
+    if (millis() - last_sensor_read_time > SENSOR_READ_INTERVAL_MS) {
+      if (gxht30_read_data(GXHT30_I2C_ADDR_DEFAULT, &sensor_data) ==
+          GXHT30_OK) {
+        // int32_t temp_int = sensor_data.temperature_x100 / 100;
+        // int32_t temp_frac = sensor_data.temperature_x100 % 100;
+        // if (temp_frac < 0) temp_frac = -temp_frac;
+
+        // int32_t hum_int = sensor_data.humidity_x100 / 100;
+        // int32_t hum_frac = sensor_data.humidity_x100 % 100;
+
+        // printf("Read Sensor -> Temp: %ld.%02ld C, Hum: %ld.%02ld %%\n",
+        //        temp_int, temp_frac, hum_int, hum_frac);
+        ha_mqtt_publish_sensor_data(sensor_data.temperature_x100,
+                                    sensor_data.humidity_x100);
+
       } else {
-        GPIOA->BSHR = (1 << (LED1_PIN + 16));
+        printf("Failed to read sensor. Error: %d\n", sensor_data.error);
       }
-      led_state = !led_state;
-      last_led_toggle_time = now;
+
+      last_sensor_read_time = millis();
     }
+
+    // uint32_t now = millis();
+    // if (now - last_led_toggle_time > LED_TOGGLE_INTERVAL_MS) {
+    //   if (led_state) {
+    //     GPIOA->BSHR = (1 << LED1_PIN);
+    //   } else {
+    //     GPIOA->BSHR = (1 << (LED1_PIN + 16));
+    //   }
+    //   led_state = !led_state;
+    //   last_led_toggle_time = now;
+    // }
   }
 }

port/arch/cc.h

@@ -32,4 +32,6 @@
 
 #define LWIP_RAND() ((u32_t)rand())
 
+#include "arch/sys_arch.h"
+
 #endif /* LWIP_ARCH_CC_H */

port/arch/sys_arch.c

@@ -1,8 +1,9 @@
+#include "sys_arch.h"
+
 #include "ch32fun.h"
-#include "lwip/def.h"
+#include "lwip/sys.h"
 #include "systick.h"
 
-typedef uint32_t sys_prot_t;
 static unsigned long next = 1;
 
 int rand(void) {
@@ -12,14 +13,14 @@ int rand(void) {
 
 void srand(unsigned int seed) { next = seed; }
 
-uint32_t sys_now(void) { return systick_millis; }
+uint32_t sys_now(void) { return millis(); }
 
 sys_prot_t sys_arch_protect(void) {
-  unsigned int old_mstatus;
-  __asm__ volatile("csrrci %0, mstatus, 8" : "=r"(old_mstatus));
-  return old_mstatus;
+  __disable_irq();
+  return 1;
 }
 
 void sys_arch_unprotect(sys_prot_t pval) {
-  __asm__ volatile("csrw mstatus, %0" : : "r"(pval));
+  (void)pval;
+  __enable_irq();
 }

port/arch/sys_arch.h

@@ -0,0 +1,8 @@
+#ifndef LWIP_ARCH_SYS_ARCH_H
+#define LWIP_ARCH_SYS_ARCH_H
+
+#include <stdint.h>
+
+typedef uint32_t sys_prot_t;
+
+#endif /* LWIP_ARCH_SYS_ARCH_H */

port/ethernetif.c

@@ -8,41 +8,24 @@
 #include "ch32v20xhw.h"
 #include "lwip/etharp.h"
 #include "lwip/snmp.h"
-#include "systick.h"
+
+#define CH32V208_ETH_IMPLEMENTATION
+#define ETH_RX_BUF_COUNT 4
+#define ETH_TX_BUF_COUNT 2
+
+#include "ch32v208_eth.h"
 
 #define IFNAME0 'e'
 #define IFNAME1 'n'
 
-#define ETH_RXBUFNB 4
-#define ETH_TXBUFNB 1
-#define ETH_RX_BUF_SZE ETH_MAX_PACKET_SIZE
-#define ETH_TX_BUF_SZE ETH_MAX_PACKET_SIZE
+static volatile bool g_link_changed = false;
 
-struct ethernetif {
-  ETH_DMADESCTypeDef* DMARxDescToGet;
-  ETH_DMADESCTypeDef* DMATxDescToSet;
-};
-
-__attribute__((aligned(4))) ETH_DMADESCTypeDef DMARxDscrTab[ETH_RXBUFNB];
-__attribute__((aligned(4))) ETH_DMADESCTypeDef DMATxDscrTab[ETH_TXBUFNB];
-__attribute__((aligned(4))) uint8_t MACRxBuf[ETH_RXBUFNB * ETH_RX_BUF_SZE];
-__attribute__((aligned(4))) uint8_t MACTxBuf[ETH_TXBUFNB * ETH_TX_BUF_SZE];
-
-static volatile bool g_link_interrupt_flag = false;
-static struct ethernetif eth_state;
-
-static void low_level_init(struct netif* netif);
+static void eth_link_callback(bool link_up);
 static err_t low_level_output(struct netif* netif, struct pbuf* p);
-static struct pbuf* low_level_input(struct netif* netif);
-void WritePHYReg(uint8_t reg_add, uint16_t reg_val);
-uint16_t ReadPHYReg(uint8_t reg_add);
 
-static void eth_get_mac_in_uc(uint8_t* mac) {
-  // Mac is backwards.
-  const uint8_t* macaddr = (const uint8_t*)(ROM_CFG_USERADR_ID + 5);
-  for (int i = 0; i < 6; i++) {
-    mac[i] = *(macaddr--);
-  }
+static void eth_link_callback(bool link_up) {
+  (void)link_up;
+  g_link_changed = true;
 }
 
 err_t ethernetif_init(struct netif* netif) {
@@ -50,7 +33,7 @@ err_t ethernetif_init(struct netif* netif) {
   netif->hostname = "lwip-ch32";
 #endif
 
-  netif->state = &eth_state;
+  netif->state = &g_eth_state;
   netif->name[0] = IFNAME0;
   netif->name[1] = IFNAME1;
 
@@ -58,217 +41,106 @@ err_t ethernetif_init(struct netif* netif) {
   netif->linkoutput = low_level_output;
 
   MIB2_INIT_NETIF(netif, snmp_ifType_ethernet_csmacd, 10000000);  // 10Mbps
+  netif->mtu = 1500;
+  netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP;
 
+  eth_config_t eth_cfg = {.mac_addr = NULL,     // we'll use part uuid MAC
+                          .rx_callback = NULL,  // no cb, polling API
+                          .link_callback = eth_link_callback,
+                          .promiscuous_mode = false,
+                          .broadcast_filter = true,
+                          .multicast_filter = true};
+
+  if (eth_init(&eth_cfg) != 0) {
+    printf("ERROR: Ethernet initialization failed\n");
+    return ERR_IF;
+  }
+
+  // get MAC from driver
   netif->hwaddr_len = ETH_HWADDR_LEN;
-  eth_get_mac_in_uc(netif->hwaddr);
+  eth_get_mac_address(netif->hwaddr);
 
   printf("MAC Address: %02X:%02X:%02X:%02X:%02X:%02X\n", netif->hwaddr[0],
          netif->hwaddr[1], netif->hwaddr[2], netif->hwaddr[3], netif->hwaddr[4],
          netif->hwaddr[5]);
 
-  netif->mtu = 1500;
-  netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP;
-
-  low_level_init(netif);
-
   return ERR_OK;
 }
 
-static void low_level_init(struct netif* netif) {
-  struct ethernetif* ethernetif = netif->state;
-
-  // clocks
-  RCC->APB2PCENR |= RCC_APB2Periph_AFIO;
-  RCC->CFGR0 |= RCC_ETHPRE;  // div 2
-  EXTEN->EXTEN_CTR |= EXTEN_ETH_10M_EN;
-
-  // reset mac rx and tx
-  ETH10M->ECON1 = RB_ETH_ECON1_TXRST | RB_ETH_ECON1_RXRST;
-  ETH10M->ECON1 = 0;
-
-  // mac regs
-  ETH10M->ERXFCON = RB_ETH_ERXFCON_BCEN | RB_ETH_ERXFCON_MCEN;
-  ETH10M->MACON1 = RB_ETH_MACON1_MARXEN;
-  ETH10M->MACON2 = PADCFG_AUTO_3 | RB_ETH_MACON2_TXCRCEN;
-  ETH10M->MAMXFL = ETH_MAX_PACKET_SIZE;
-
-  R8_ETH_MAADRL1 = netif->hwaddr[5];
-  R8_ETH_MAADRL2 = netif->hwaddr[4];
-  R8_ETH_MAADRL3 = netif->hwaddr[3];
-  R8_ETH_MAADRL4 = netif->hwaddr[2];
-  R8_ETH_MAADRL5 = netif->hwaddr[1];
-  R8_ETH_MAADRL6 = netif->hwaddr[0];
-
-  // PHY analog block
-  ETH10M->ECON2 = RB_ETH_ECON2_DEFAULT;
-
-  // init TX descriptors
-  ethernetif->DMATxDescToSet = DMATxDscrTab;
-  for (int i = 0; i < ETH_TXBUFNB; i++) {
-    DMATxDscrTab[i].Status = 0;
-    DMATxDscrTab[i].Buffer1Addr = (uint32_t)&MACTxBuf[i * ETH_TX_BUF_SZE];
-    DMATxDscrTab[i].Buffer2NextDescAddr =
-        (uint32_t)&DMATxDscrTab[(i + 1) % ETH_TXBUFNB];
-  }
-
-  // init RX descriptors
-  ethernetif->DMARxDescToGet = DMARxDscrTab;
-  for (int i = 0; i < ETH_RXBUFNB; i++) {
-    DMARxDscrTab[i].Status = 0;
-    DMARxDscrTab[i].Buffer1Addr = (uint32_t)&MACRxBuf[i * ETH_RX_BUF_SZE];
-    DMARxDscrTab[i].Buffer2NextDescAddr =
-        (uint32_t)&DMARxDscrTab[(i + 1) % ETH_RXBUFNB];
-  }
-
-  // set RX buffer start and enable receiver
-  ETH10M->ERXST = ethernetif->DMARxDescToGet->Buffer1Addr;
-  ETH10M->ECON1 = RB_ETH_ECON1_RXEN;
-
-  WritePHYReg(PHY_BMCR, PHY_BMCR_RESET);
-  Delay_Ms(200);
-
-  WritePHYReg(PHY_BMCR, PHY_BMCR_FULL_DUPLEX);
-
-  ETH10M->EIR = 0xFF;  // clear all interrupt flags
-  ETH10M->EIE = RB_ETH_EIE_INTIE | RB_ETH_EIE_TXIE | RB_ETH_EIE_LINKIE |
-                RB_ETH_EIE_TXERIE | RB_ETH_EIE_RXERIE | RB_ETH_EIE_R_EN50;
-
-  NVIC_EnableIRQ(ETH_IRQn);
-}
-
 static err_t low_level_output(struct netif* netif, struct pbuf* p) {
   (void)netif;
 
-  if (DMATxDscrTab[0].Status & ETH_DMATxDesc_OWN) {
-    LINK_STATS_INC(link.drop);
-    return ERR_BUF;
+  // single-segment pbuf
+  if (p->next == NULL && p->len <= ETH_TX_BUF_SIZE) {
+    if (eth_send_packet(p->payload, p->len) == 0) {
+      LINK_STATS_INC(link.xmit);
+      return ERR_OK;
+    }
   }
 
-  uint32_t len = 0;
-  uint8_t* tx_buf_ptr = (uint8_t*)DMATxDscrTab[0].Buffer1Addr;
+  // chain of pbufs
+  static uint8_t tx_buffer[ETH_TX_BUF_SIZE];
+  uint32_t total_len = 0;
 
   for (struct pbuf* q = p; q != NULL; q = q->next) {
-    memcpy(&tx_buf_ptr[len], q->payload, q->len);
-    len += q->len;
-  }
-
-  ETH10M->ETXLN = len;
-  ETH10M->ETXST = (uint32_t)tx_buf_ptr;
-  DMATxDscrTab[0].Status |= ETH_DMATxDesc_OWN;
-  ETH10M->ECON1 |= RB_ETH_ECON1_TXRTS;
-
-  LINK_STATS_INC(link.xmit);
-  MIB2_STATS_NETIF_ADD(netif, ifoutoctets, len);
-
-  return ERR_OK;
-}
-
-static struct pbuf* low_level_input(struct netif* netif) {
-  struct ethernetif* ethernetif = netif->state;
-
-  if (!(ETH10M->EIR & RB_ETH_EIR_RXIF)) {
-    return NULL;
-  }
-
-  uint16_t len = ETH10M->ERXLN;
-
-  if (len < MIN_ETH_FRAME_SIZE || len > ETH_MAX_PACKET_SIZE) {
-    LINK_STATS_INC(link.lenerr);
-    ETH10M->EIR = RB_ETH_EIR_RXIF;
-    ETH10M->ECON1 |= RB_ETH_ECON1_RXEN;
-    return NULL;
-  }
-
-  uint8_t* current_rx_buffer_ptr =
-      (uint8_t*)ethernetif->DMARxDescToGet->Buffer1Addr;
-
-  struct pbuf* p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
-  if (p != NULL) {
-    uint32_t offset = 0;
-    for (struct pbuf* q = p; q != NULL; q = q->next) {
-      memcpy(q->payload, current_rx_buffer_ptr + offset, q->len);
-      offset += q->len;
+    if (total_len + q->len > ETH_TX_BUF_SIZE) {
+      LINK_STATS_INC(link.err);
+      return ERR_BUF;
     }
-    LINK_STATS_INC(link.recv);
-    MIB2_STATS_NETIF_ADD(netif, ifinoctets, len);
-  } else {
-    LINK_STATS_INC(link.memerr);
-    LINK_STATS_INC(link.drop);
-    MIB2_STATS_NETIF_INC(netif, ifindiscards);
+    memcpy(&tx_buffer[total_len], q->payload, q->len);
+    total_len += q->len;
   }
 
-  // move to next descriptor
-  ethernetif->DMARxDescToGet =
-      (ETH_DMADESCTypeDef*)ethernetif->DMARxDescToGet->Buffer2NextDescAddr;
-  ETH10M->ERXST = (uint32_t)ethernetif->DMARxDescToGet->Buffer1Addr;
-  ETH10M->EIR = RB_ETH_EIR_RXIF;
-  ETH10M->ECON1 |= RB_ETH_ECON1_RXEN;
+  if (eth_send_packet(tx_buffer, total_len) == 0) {
+    LINK_STATS_INC(link.xmit);
+    return ERR_OK;
+  }
 
-  return p;
+  LINK_STATS_INC(link.drop);
+  return ERR_BUF;
 }
 
 void ethernetif_input(struct netif* netif) {
-  struct pbuf* p;
-  while ((p = low_level_input(netif)) != NULL) {
-    if (netif->input(p, netif) != ERR_OK) {
-      pbuf_free(p);
+  uint16_t length;
+  const uint8_t* packet;
+
+  // process all pending packets using polling API
+  while ((packet = eth_get_rx_packet(&length)) != NULL) {
+    struct pbuf* p = pbuf_alloc(PBUF_RAW, length, PBUF_POOL);
+
+    if (p != NULL) {
+      // usually contiguous in PBUF_POOL
+      pbuf_take(p, packet, length);
+      LINK_STATS_INC(link.recv);
+
+      // pass to lwIP
+      if (netif->input(p, netif) != ERR_OK) {
+        pbuf_free(p);
+      }
+    } else {
+      // oom
+      LINK_STATS_INC(link.memerr);
+      LINK_STATS_INC(link.drop);
     }
+
+    // release packet back to driver
+    eth_release_rx_packet();
   }
 }
 
 void ethernetif_link_poll(struct netif* netif) {
-  if (!g_link_interrupt_flag) return;
-  g_link_interrupt_flag = false;
+  // driver does PHY polling and autoneg
+  eth_poll_link();
 
-  // supposedly, first read latches link status 2nd get cur val
-  (void)ReadPHYReg(PHY_BMSR);
-  uint16_t bmsr = ReadPHYReg(PHY_BMSR);
+  if (g_link_changed) {
+    g_link_changed = false;
 
-  if (bmsr & PHY_BMSR_LINK_STATUS) {
-    if (!netif_is_link_up(netif)) {
-      ETH10M->MACON2 |= RB_ETH_MACON2_FULDPX;
+    bool link_up = eth_is_link_up();
+
+    if (link_up && !netif_is_link_up(netif)) {
       netif_set_link_up(netif);
-    }
-  } else {
-    if (netif_is_link_up(netif)) {
+    } else if (!link_up && netif_is_link_up(netif)) {
       netif_set_link_down(netif);
     }
   }
 }
-
-void ETH_IRQHandler(void) __attribute__((interrupt)) __attribute__((used));
-void ETH_IRQHandler(void) {
-  uint32_t flags = ETH10M->EIR;
-
-  if (flags & RB_ETH_EIR_TXIF) {
-    DMATxDscrTab[0].Status &= ~ETH_DMATxDesc_OWN;
-    ETH10M->EIR = RB_ETH_EIR_TXIF;
-  }
-
-  if (flags & RB_ETH_EIR_TXERIF) {
-    DMATxDscrTab[0].Status &= ~ETH_DMATxDesc_OWN;
-    ETH10M->EIR = RB_ETH_EIR_TXERIF;
-    LINK_STATS_INC(link.err);
-  }
-
-  if (flags & RB_ETH_EIR_RXERIF) {
-    ETH10M->EIR = RB_ETH_EIR_RXERIF;
-    ETH10M->ECON1 |= RB_ETH_ECON1_RXEN;
-    LINK_STATS_INC(link.err);
-  }
-
-  if (flags & RB_ETH_EIR_LINKIF) {
-    g_link_interrupt_flag = true;
-    ETH10M->EIR = RB_ETH_EIR_LINKIF;
-  }
-}
-
-void WritePHYReg(uint8_t reg_add, uint16_t reg_val) {
-  R32_ETH_MIWR = (reg_add & RB_ETH_MIREGADR_MASK) | RB_ETH_MIWR_MIIWR |
-                 (reg_val << RB_ETH_MIWR_DATA_SHIFT);
-}
-
-uint16_t ReadPHYReg(uint8_t reg_add) {
-  ETH10M->MIERGADR = reg_add;
-  return ETH10M->MIRD;
-}

port/ethernetif.h

@@ -4,57 +4,45 @@
 #include "lwip/err.h"
 #include "lwip/netif.h"
 
-void run_tx_test(void);
-void WritePHYReg(uint8_t reg_add, uint16_t reg_val);
-uint16_t ReadPHYReg(uint8_t reg_add);
-
-#define ROM_CFG_USERADR_ID 0x1FFFF7E8
-
-#define ETH_DMARxDesc_FrameLengthShift 16
-
-#define ETH_MAX_PACKET_SIZE \
-  1536 /* ETH_HEADER + VLAN_TAG + MAX_ETH_PAYLOAD + ETH_CRC */
-#define ETH_HEADER                                                           \
-  14                /* 6 byte Dest addr, 6 byte Src addr, 2 byte length/type \
-                     */
-#define ETH_CRC 4   /* Ethernet CRC */
-#define ETH_EXTRA 2 /* Extra bytes in some cases */
-#define VLAN_TAG 4  /* optional 802.1q VLAN Tag */
-#define MIN_ETH_PAYLOAD 46   /* Minimum Ethernet payload size */
-#define MAX_ETH_PAYLOAD 1500 /* Maximum Ethernet payload size */
-#define MIN_ETH_FRAME_SIZE (ETH_HEADER + MIN_ETH_PAYLOAD) /* 60 bytes */
-
-typedef struct {
-  uint32_t volatile Status;     /* Status */
-  uint32_t ControlBufferSize;   /* Control and Buffer1, Buffer2 lengths */
-  uint32_t Buffer1Addr;         /* Buffer1 address pointer */
-  uint32_t Buffer2NextDescAddr; /* Buffer2 or next descriptor address pointer */
-} ETH_DMADESCTypeDef;
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 /**
- * @brief Initialize the ethernet interface and lwIP network stack.
- *        This function should be passed as the init function to netif_add().
+ * Should be called at the beginning of the program to set up the
+ * network interface. It calls the function low_level_init() to do the
+ * actual setup of the hardware.
  *
- * @param netif The lwIP network interface structure to be initialized.
- * @return ERR_OK if the loopif is initialized, ERR_MEM if private data couldn't
- * be allocated.
+ * This function should be passed as a parameter to netif_add().
+ *
+ * @param netif the lwip network interface structure for this ethernetif
+ * @return ERR_OK if the loopif is initialized
+ *         ERR_MEM if private data couldn't be allocated
+ *         any other err_t on error
  */
 err_t ethernetif_init(struct netif* netif);
 
 /**
- * @brief This function should be called periodically from your main loop
- *        to check for incoming packets and pass them to lwIP.
+ * This function should be called when a packet is ready to be read
+ * from the interface. It uses the function low_level_input() that
+ * should handle the actual reception of bytes from the network
+ * interface. Then the type of the received packet is determined and
+ * the appropriate input function is called.
  *
- * @param netif The lwIP network interface structure.
+ * @param netif the lwip network interface structure for this ethernetif
  */
 void ethernetif_input(struct netif* netif);
 
 /**
- * @brief This function should be called periodically from your main loop
- *        to check the link status and update lwIP accordingly.
+ * This function should be called periodically from the main loop
+ * to check the link status and update lwIP accordingly.
  *
- * @param netif The lwIP network interface structure..
+ * @param netif the lwip network interface structure for this ethernetif
  */
 void ethernetif_link_poll(struct netif* netif);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* __ETHERNETIF_H */

port/lwipopts.h

@@ -11,59 +11,53 @@
 // #define ETHARP_DEBUG LWIP_DBG_ON
 
 #define NO_SYS 1
-
-// Core locking
 #define SYS_LIGHTWEIGHT_PROT 0
-
-// Memory options
-#define MEM_ALIGNMENT 4
-#define MEM_SIZE (10 * 1024)  // 4KB of RAM for lwIP heap
-
-// Pbuf options
-#define PBUF_POOL_SIZE 24      // Enough for bursts
-#define PBUF_POOL_BUFSIZE 600  // ~500 byte typical packet + header
-
-// TCP options
-#define LWIP_TCP 1
-#define TCP_MSS 1460
-#define TCP_SND_BUF (2 * TCP_MSS)
-
-// UDP options
-#define LWIP_UDP 1
-
-// ICMP options
-#define LWIP_ICMP 1
-
-// DHCP options
-#define LWIP_DHCP 1
-
-// Checksum options
-// #define CHECKSUM_GEN_IP               0
-// #define CHECKSUM_GEN_UDP              0
-// #define CHECKSUM_GEN_TCP              0
-// #define CHECKSUM_CHECK_IP             0
-#define CHECKSUM_CHECK_UDP 0
-// #define CHECKSUM_CHECK_TCP            0
-// #define LWIP_CHECKSUM_ON_COPY         1
-
 #define LWIP_NETCONN 0
 #define LWIP_SOCKET 0
 
-// Statistics
-#define LWIP_STATS 0
-#define LINK_STATS 0
-#define MIB2_STATS 0
+// Memory options
+#define MEM_ALIGNMENT 4
+#define MEM_SIZE (4 * 1024)
 
+// Pbuf options
+#define PBUF_POOL_SIZE 16
+#define PBUF_POOL_BUFSIZE 590
+
+// TCP options
+#define LWIP_TCP 1
+#define TCP_MSS 536
+#define TCP_SND_BUF (2 * TCP_MSS)
+#define TCP_WND (4 * TCP_MSS)
+#define TCP_QUEUE_OOSEQ 0
+
+#define LWIP_UDP 1
+#define MEMP_NUM_UDP_PCB 3  // # of concurrent UDP "connections"
+#define MEMP_NUM_SYS_TIMEOUT 8
+#define LWIP_ICMP 1
+
+#define LWIP_DHCP 1
 #define LWIP_HTTPD 1
-// Use a read-only filesystem populated by makefsdata
-// #define HTTPD_FSDATA_FILE "fsdata_custom.c"
 #define LWIP_HTTPD_FS_SUPPORT 1
 #define HTTPD_USE_CUSTOM_FSDATA 1
 
+// MQTT
+#define LWIP_MQTT_CLIENT 1
+#define MQTT_OUTPUT_RINGBUF_SIZE 512
+
 #define LWIP_NETIF_HOSTNAME 1
 #define LWIP_NETIF_LINK_CALLBACK 1
 #define LWIP_NETIF_STATUS_CALLBACK 1
+#define LWIP_SUPPORT_CUSTOM_PBUF 1  // for zero-copy
 
-#define LWIP_SUPPORT_CUSTOM_PBUF 1
+#define CHECKSUM_GEN_IP 1
+#define CHECKSUM_GEN_UDP 1
+#define CHECKSUM_GEN_TCP 1
+#define CHECKSUM_CHECK_IP 1
+#define CHECKSUM_CHECK_UDP 1
+#define CHECKSUM_CHECK_TCP 1
+#define LWIP_CHECKSUM_ON_COPY 0
+
+#define LWIP_STATS 0
+#define LINK_STATS 0
 
 #endif /* __LWIPOPTS_H__ */