From 124abf02137ff4588f65259c64d2c719b81ae2e7 Mon Sep 17 00:00:00 2001
From: "Jakob.Meier" <–meierj@irs.uni-stuttgart.de>
Date: Wed, 18 Aug 2021 08:26:31 +0200
Subject: [PATCH] crc for ploc update

---
 README.md                                     |  2 +-
 bsp_q7s/devices/PlocUpdater.cpp               | 28 +++++++++++++++----
 bsp_q7s/devices/PlocUpdater.h                 |  7 ++++-
 .../PlocSupervisorDefinitions.h               |  2 +-
 4 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/README.md b/README.md
index d75c535b..cb2f9f53 100644
--- a/README.md
+++ b/README.md
@@ -926,7 +926,7 @@ candump can0
 
 ## Dump content of file in hex
 ````
-cat file.bin | hexdump
+cat file.bin | hexdump -C
 ````
 
 ## Preparation of a fresh rootfs and SD card
diff --git a/bsp_q7s/devices/PlocUpdater.cpp b/bsp_q7s/devices/PlocUpdater.cpp
index 0e4ea77d..c37855a4 100644
--- a/bsp_q7s/devices/PlocUpdater.cpp
+++ b/bsp_q7s/devices/PlocUpdater.cpp
@@ -292,7 +292,7 @@ void PlocUpdater::commandUpdateAvailable() {
     remainingPackets = numOfUpdatePackets;
     packetsSent = 0;
 
-    uint32_t imageCrc = makeCrc();
+    calcImageCrc();
 
     PLOC_SPV::UpdateInfo packet(PLOC_SPV::APID_UPDATE_AVAILABLE, static_cast<uint8_t>(updateMemory),
             static_cast<uint8_t>(updatePartition), imageSize, imageCrc, numOfUpdatePackets);
@@ -338,7 +338,7 @@ void PlocUpdater::commandUpdatePacket() {
     file.close();
     // sequence count of first packet is 1
     packet.setPacketSequenceCount((packetsSent + 1) & PLOC_SPV::SEQUENCE_COUNT_MASK);
-    if (numOfUpdatePackets > 0) {
+    if (numOfUpdatePackets > 1) {
         adjustSequenceFlags(packet);
     }
     packet.makeCrc();
@@ -383,9 +383,27 @@ void PlocUpdater::commandUpdateVerify() {
     return;
 }
 
-ReturnValue_t PlocUpdater::makeCrc() {
-    //TODO: Waiting on input from TAS about the CRC to use
-    return 0;
+void PlocUpdater::calcImageCrc() {
+    std::ifstream file(updateFile, std::ifstream::binary);
+    file.seekg(0, file.end);
+    uint32_t count;
+    uint32_t bit;
+    uint32_t remainder = INITIAL_REMAINDER_32;
+    char input;
+    for (count = 0; count < imageSize; count++) {
+        file.seekg(count, file.beg);
+        file.read(&input, 1);
+        remainder ^= (input << 16);
+        for (bit = 8; bit > 0; --bit) {
+            if (remainder & TOPBIT_32) {
+                remainder = (remainder << 1) ^ POLYNOMIAL_32;
+            } else {
+                remainder = (remainder << 1);
+            }
+        }
+    }
+    file.close();
+    imageCrc = (remainder ^ FINAL_XOR_VALUE_32);
 }
 
 void PlocUpdater::adjustSequenceFlags(PLOC_SPV::UpdatePacket& packet) {
diff --git a/bsp_q7s/devices/PlocUpdater.h b/bsp_q7s/devices/PlocUpdater.h
index 8d7d9e30..c8a2b67b 100644
--- a/bsp_q7s/devices/PlocUpdater.h
+++ b/bsp_q7s/devices/PlocUpdater.h
@@ -92,6 +92,11 @@ private:
     // Maximum size of update payload data per space packet (max size of space packet is 1024 bytes)
     static const size_t MAX_SP_DATA = 1016;
 
+    static const uint32_t TOPBIT_32 = (1 << 31);
+    static const uint32_t POLYNOMIAL_32 = 0x04C11DB7;
+    static const uint32_t INITIAL_REMAINDER_32 = 0xFFFFFFFF;
+    static const uint32_t FINAL_XOR_VALUE_32 = 0xFFFFFFFF;
+
     MessageQueueIF* commandQueue = nullptr;
 
 #if BOARD_TE0720 == 0
@@ -168,7 +173,7 @@ private:
     bool isSdCardMounted(sd::SdCard sdCard);
 #endif
 
-    ReturnValue_t makeCrc();
+    void calcImageCrc();
 
     void adjustSequenceFlags(PLOC_SPV::UpdatePacket& packet);
 };
diff --git a/bsp_q7s/devices/devicedefinitions/PlocSupervisorDefinitions.h b/bsp_q7s/devices/devicedefinitions/PlocSupervisorDefinitions.h
index 909379df..26d44272 100644
--- a/bsp_q7s/devices/devicedefinitions/PlocSupervisorDefinitions.h
+++ b/bsp_q7s/devices/devicedefinitions/PlocSupervisorDefinitions.h
@@ -1453,7 +1453,7 @@ public:
     UpdateInfo(uint16_t apid, uint8_t memory, uint8_t partition, uint32_t imageSize,
             uint32_t imageCrc, uint32_t numPackets) :
             SupvTcSpacePacket(PAYLOAD_LENGTH, apid), memory(memory), partition(partition), imageSize(
-                    imageSize), numPackets(numPackets) {
+                    imageSize), imageCrc(imageCrc), numPackets(numPackets) {
         initPacket();
         makeCrc();
     }