opencsd: etm4x: ete: Fix timestamp value extractions

For 64 bit timestamp values with the top bit (63) set, this was being incorrectly masked to 1b0 by the extraction routine.
Handling of 9th (final) byte in the value extraction changed to fix this issue.

Signed-off-by: Mike Leach <mike.leach@linaro.org>

2 files changed, 24 insertions, 7 deletions

diff --git a/decoder/include/opencsd/etmv4/trc_pkt_proc_etmv4i.h b/decoder/include/opencsd/etmv4/trc_pkt_proc_etmv4i.h
index 45f8810a5c98..19388c38c371 100644
--- a/decoder/include/opencsd/etmv4/trc_pkt_proc_etmv4i.h
+++ b/decoder/include/opencsd/etmv4/trc_pkt_proc_etmv4i.h
@@ -181,7 +181,7 @@ private:
     void iPktInvalidCfg(const uint8_t lastByte);  // packet invalid in current config.
 
     unsigned extractContField(const std::vector<uint8_t> &buffer, const unsigned st_idx, uint32_t &value, const unsigned byte_limit = 5);
-    unsigned extractContField64(const std::vector<uint8_t> &buffer, const unsigned st_idx, uint64_t &value, const unsigned byte_limit = 9);
+    unsigned extractTSField64(const std::vector<uint8_t> &buffer, const unsigned st_idx, uint64_t &value);
     unsigned extractCondResult(const std::vector<uint8_t> &buffer, const unsigned st_idx, uint32_t& key, uint8_t &result);
     void extractAndSetContextInfo(const std::vector<uint8_t> &buffer, const int st_idx);
     int extract64BitLongAddr(const std::vector<uint8_t> &buffer, const int st_idx, const uint8_t IS, uint64_t &value);
diff --git a/decoder/source/etmv4/trc_pkt_proc_etmv4i.cpp b/decoder/source/etmv4/trc_pkt_proc_etmv4i.cpp
index 0abb605faf43..d0573d6c29bf 100644
--- a/decoder/source/etmv4/trc_pkt_proc_etmv4i.cpp
+++ b/decoder/source/etmv4/trc_pkt_proc_etmv4i.cpp
@@ -522,8 +522,11 @@ void TrcPktProcEtmV4I::iPktTimestamp(const uint8_t lastByte)
     {        
         int idx = 1;
         uint64_t tsVal;
-        int ts_bytes = extractContField64(m_currPacketData, idx, tsVal);
-        int ts_bits = ts_bytes < 7 ? ts_bytes * 7 : 64;
+        int ts_bytes = extractTSField64(m_currPacketData, idx, tsVal);
+        int ts_bits;
+        
+        // if ts_bytes 8 or less, then cont bits on each byte, otherwise full 64 bit value for 9 bytes
+        ts_bits = ts_bytes < 9 ? ts_bytes * 7 : 64;
 
         if(!m_curr_packet.pkt_valid.bits.ts_valid && m_first_trace_info)
             ts_bits = 64;   // after trace info, missing bits are all 0.
@@ -1653,20 +1656,33 @@ void TrcPktProcEtmV4I::BuildIPacketTable()
     return idx;
 }
 
-unsigned TrcPktProcEtmV4I::extractContField64(const std::vector<uint8_t> &buffer, const unsigned st_idx, uint64_t &value, const unsigned byte_limit /*= 9*/)
+unsigned TrcPktProcEtmV4I::extractTSField64(const std::vector<uint8_t> &buffer, const unsigned st_idx, uint64_t &value)
 {
+    const unsigned max_byte_idx = 8;    /* the 9th byte, index 8, will use full 8 bits for value */
     unsigned idx = 0;
     bool lastByte = false;
     uint8_t byteVal;
+    uint8_t byteValMask = 0x7f;
+    
+    /* init value */
     value = 0;
-    while(!lastByte && (idx < byte_limit))   // max 9 bytes for 64 bit value;
+    while(!lastByte)   // max 9 bytes for 64 bit value;
     {
         if(buffer.size() > (st_idx + idx))
         {
             // each byte has seven bits + cont bit
             byteVal = buffer[(st_idx + idx)];
-            lastByte = (byteVal & 0x80) != 0x80;
-            value |= ((uint64_t)(byteVal & 0x7F)) << (idx * 7);
+
+            /* detect the final byte - which uses full 8 bits as value */
+            if (idx == max_byte_idx)
+            {
+                byteValMask = 0xFF;  /* last byte of 9, no cont bit */
+                lastByte = true;
+            }
+            else 
+                lastByte = (byteVal & 0x80) != 0x80;
+
+            value |= ((uint64_t)(byteVal & byteValMask)) << (idx * 7);
             idx++;
         }
         else
@@ -1674,6 +1690,7 @@ unsigned TrcPktProcEtmV4I::extractContField64(const std::vector<uint8_t> &buffer
             throwBadSequenceError("Invalid 64 bit continuation fields in packet");
         }
     }
+    // index is the count of bytes used here.
     return idx;
 }