Initial implementation of RTCMEM storage (#1420)

- store system crash counter and reset reason in rtcmem instead of eeprom
- store relay state mask in rtc in addition to the eeprom
- store relay state in eeprom only when boot mode requires it
- simplify relay state mask calculation / reading using std::bitset
- light state save and restore
- energy total save and restore

code/espurna/config/general.h

@@ -399,6 +399,11 @@
 #define RELAY_MQTT_OFF              "0"
 #endif
 
+// TODO Only single EEPROM address is used to store state, which is 1 byte
+// Relay status is stored using bitfield.
+// This means that, atm, we are only storing the status of the first 8 relays.
+#define RELAY_SAVE_MASK_MAX         8
+
 // -----------------------------------------------------------------------------
 // WIFI
 // -----------------------------------------------------------------------------

code/espurna/config/prototypes.h

@@ -6,10 +6,19 @@
 
 extern "C" {
     #include "user_interface.h"
+    extern struct rst_info resetInfo;
 }
 
 #define UNUSED(x) (void)(x)
 
+// -----------------------------------------------------------------------------
+// System
+// -----------------------------------------------------------------------------
+
+uint32_t systemResetReason();
+uint8_t systemStabilityCounter();
+void systemStabilityCounter(uint8_t);
+
 // -----------------------------------------------------------------------------
 // API
 // -----------------------------------------------------------------------------
@@ -134,6 +143,11 @@ typedef struct {
     int16_t rssi;
 } packet_t;
 
+// -----------------------------------------------------------------------------
+// Relay
+// -----------------------------------------------------------------------------
+#include <bitset>
+
 // -----------------------------------------------------------------------------
 // Settings
 // -----------------------------------------------------------------------------
@@ -214,7 +228,6 @@ typedef std::function<void(justwifi_messages_t code, char * parameter)> wifi_cal
 void wifiRegister(wifi_callback_f callback);
 bool wifiConnected();
 
-// -----------------------------------------------------------------------------
 // THERMOSTAT
 // -----------------------------------------------------------------------------
 #if THERMOSTAT_SUPPORT
@@ -224,3 +237,8 @@ bool wifiConnected();
     #define thermostat_callback_f void *
 #endif
 
+// -----------------------------------------------------------------------------
+// RTC MEMORY
+// -----------------------------------------------------------------------------
+#include "rtcmem.h"
+

code/espurna/config/rtcmem.h

@@ -0,0 +1,44 @@
+#pragma once
+
+// Base address of USER RTC memory
+// https://github.com/esp8266/esp8266-wiki/wiki/Memory-Map#memmory-mapped-io-registers
+#define RTCMEM_ADDR_BASE (0x60001200)
+
+// RTC memory is accessed using blocks of 4 bytes.
+// Blocks 0..63 are reserved by the SDK, 64..192 are available to the user.
+// Blocks 64..96 are reserved by the eboot 'struct eboot_command' (128 -> (128 / 4) -> 32):
+// https://github.com/esp8266/Arduino/blob/master/bootloaders/eboot/eboot_command.h
+#define RTCMEM_OFFSET 32u
+#define RTCMEM_ADDR (RTCMEM_ADDR_BASE + (RTCMEM_OFFSET * 4u))
+
+#define RTCMEM_BLOCKS 96u
+
+// Change this when modifying RtcmemData
+#define RTCMEM_MAGIC 0x45535075
+
+// XXX When using bitfields / inner structs / etc:
+// ...
+// uint32_t a : 8;
+// uint32_t b : 8;
+// uint32_t c : 8;
+// uint32_t d : 8;
+// ...
+// mem->d = 4;
+// At the same time writes 4 to the a, b and c
+
+// TODO replace with custom memory segment in ldscript
+struct RtcmemData {
+    uint32_t magic;
+    uint32_t sys;
+    uint32_t relay;
+    uint32_t mqtt;
+    uint64_t light;
+    double energy;
+};
+
+static_assert(sizeof(RtcmemData) <= (RTCMEM_BLOCKS * 4u), "RTCMEM struct is too big");
+constexpr uint8_t RtcmemSize = (sizeof(RtcmemData) / 4u);
+
+auto Rtcmem = reinterpret_cast<volatile RtcmemData*>(RTCMEM_ADDR);
+
+bool rtcmemStatus();

code/espurna/espurna.ino

@@ -67,6 +67,9 @@ void setup() {
         debugSetup();
     #endif
 
+    // Init RTCMEM
+    rtcmemSetup();
+
     // Init EEPROM
     eepromSetup();
 

code/espurna/light.ino

@@ -470,7 +470,47 @@ void _lightProviderUpdate() {
 // PERSISTANCE
 // -----------------------------------------------------------------------------
 
-void _lightColorSave() {
+union light_rtcmem_t {
+    struct {
+        uint8_t channels[5];
+        uint8_t brightness;
+        uint16_t mired;
+    } packed;
+    uint64_t value;
+};
+
+#define LIGHT_RTCMEM_CHANNELS_MAX sizeof(light_rtcmem_t().packed.channels)
+
+void _lightSaveRtcmem() {
+    if (lightChannels() > LIGHT_RTCMEM_CHANNELS_MAX) return;
+
+    light_rtcmem_t light;
+
+    for (unsigned int i=0; i < lightChannels(); i++) {
+        light.packed.channels[i] = _light_channel[i].inputValue;
+    }
+
+    light.packed.brightness = _light_brightness;
+    light.packed.mired = _light_mireds;
+
+    Rtcmem->light = light.value;
+}
+
+void _lightRestoreRtcmem() {
+    if (lightChannels() > LIGHT_RTCMEM_CHANNELS_MAX) return;
+
+    light_rtcmem_t light;
+    light.value = Rtcmem->light;
+
+    for (unsigned int i=0; i < lightChannels(); i++) {
+        _light_channel[i].inputValue = light.packed.channels[i];
+    }
+
+    _light_brightness = light.packed.brightness;
+    _light_mireds = light.packed.mired;
+}
+
+void _lightSaveSettings() {
     for (unsigned int i=0; i < _light_channel.size(); i++) {
         setSetting("ch", i, _light_channel[i].inputValue);
     }
@@ -479,7 +519,7 @@ void _lightColorSave() {
     saveSettings();
 }
 
-void _lightColorRestore() {
+void _lightRestoreSettings() {
     for (unsigned int i=0; i < _light_channel.size(); i++) {
         _light_channel[i].inputValue = getSetting("ch", i, i==0 ? 255 : 0).toInt();
     }
@@ -699,9 +739,11 @@ void lightUpdate(bool save, bool forward, bool group_forward) {
     if (group_forward) mask += 2;
     _light_comms_ticker.once_ms(LIGHT_COMMS_DELAY, _lightComms, mask);
 
+    _lightSaveRtcmem();
+
     #if LIGHT_SAVE_ENABLED
         // Delay saving to EEPROM 5 seconds to avoid wearing it out unnecessarily
-        if (save) _light_save_ticker.once(LIGHT_SAVE_DELAY, _lightColorSave);
+        if (save) _light_save_ticker.once(LIGHT_SAVE_DELAY, _lightSaveSettings);
     #endif
 
 };
@@ -712,7 +754,7 @@ void lightUpdate(bool save, bool forward) {
 
 #if LIGHT_SAVE_ENABLED == 0
 void lightSave() {
-    _lightColorSave();
+    _lightSaveSettings();
 }
 #endif
 
@@ -1166,7 +1208,11 @@ void lightSetup() {
     DEBUG_MSG_P(PSTR("[LIGHT] Number of channels: %d\n"), _light_channel.size());
 
     _lightConfigure();
-    _lightColorRestore();
+    if (rtcmemStatus()) {
+        _lightRestoreRtcmem();
+    } else {
+        _lightRestoreSettings();
+    }
 
     #if WEB_SUPPORT
         wsOnSendRegister(_lightWebSocketOnSend);

code/espurna/mqtt.ino

@@ -267,48 +267,6 @@ void _mqttBackwards() {
     }
 }
 
-unsigned long _mqttNextMessageId() {
-
-    static unsigned long id = 0;
-
-    // just reboot, get last count from EEPROM
-    if (id == 0) {
-
-        // read id from EEPROM and shift it
-        id = EEPROMr.read(EEPROM_MESSAGE_ID);
-        if (id == 0xFF) {
-
-            // There was nothing in EEPROM,
-            // next message is first message
-            id = 0;
-
-        } else {
-
-            id = (id << 8) + EEPROMr.read(EEPROM_MESSAGE_ID + 1);
-            id = (id << 8) + EEPROMr.read(EEPROM_MESSAGE_ID + 2);
-            id = (id << 8) + EEPROMr.read(EEPROM_MESSAGE_ID + 3);
-
-            // Calculate next block and start from there
-            id = MQTT_MESSAGE_ID_SHIFT * (1 + (id / MQTT_MESSAGE_ID_SHIFT));
-
-        }
-
-    }
-
-    // Save to EEPROM every MQTT_MESSAGE_ID_SHIFT
-    if (id % MQTT_MESSAGE_ID_SHIFT == 0) {
-        EEPROMr.write(EEPROM_MESSAGE_ID + 0, (id >> 24) & 0xFF);
-        EEPROMr.write(EEPROM_MESSAGE_ID + 1, (id >> 16) & 0xFF);
-        EEPROMr.write(EEPROM_MESSAGE_ID + 2, (id >>  8) & 0xFF);
-        EEPROMr.write(EEPROM_MESSAGE_ID + 3, (id >>  0) & 0xFF);
-        eepromCommit();
-    }
-
-    id++;
-    return id;
-
-}
-
 // -----------------------------------------------------------------------------
 // WEB
 // -----------------------------------------------------------------------------
@@ -628,7 +586,7 @@ void mqttFlush() {
         root[MQTT_TOPIC_IP] = getIP();
     #endif
     #if MQTT_ENQUEUE_MESSAGE_ID
-        root[MQTT_TOPIC_MESSAGE_ID] = _mqttNextMessageId();
+        root[MQTT_TOPIC_MESSAGE_ID] = (Rtcmem->mqtt)++;
     #endif
 
     // Send