[sc] Only change channel when necessary

Author: kostorr

src/Ic.cxx

@@ -54,7 +54,6 @@ static constexpr roc::Register IC_RD_DATA(IC_BASE.address + 0x30);
 
 Ic::Ic(AlfLink link) : mBar2(link.bar), mLink(link)
 {
-  setChannel(mLink.linkId);
   reset();
 
   // Set CFG to 0x3 by default
@@ -88,9 +87,6 @@ void Ic::init(const roc::Parameters::CardIdType& cardId, int linkId)
 
   mLlaSession = std::make_unique<LlaSession>("DDT", card.sequenceId);
 
-  if (mLink.linkId != -1) {
-    setChannel(mLink.linkId);
-  }
   reset();
 
   // Set CFG to 0x3 by default
@@ -108,6 +104,12 @@ void Ic::checkChannelSet()
   if (mLink.linkId == -1) {
     BOOST_THROW_EXCEPTION(IcException() << ErrorInfo::Message("No IC channel selected"));
   }
+
+  uint32_t channel = (barRead(sc_regs::SWT_MON.index) >> 8) & 0xff;
+
+  if (channel != mLink.linkId) {
+    setChannel(mLink.linkId);
+  }
 }
 
 void Ic::reset()
@@ -211,7 +213,6 @@ std::vector<std::pair<Ic::Operation, Ic::Data>> Ic::executeSequence(std::vector<
   } catch (const IcException& e) {
     return { { Operation::Error, e.what() } };
   }
-  setChannel(mLink.linkId);
 
   std::vector<std::pair<Ic::Operation, Ic::Data>> ret;
   for (const auto& it : ops) {

src/Sca.cxx

@@ -92,6 +92,12 @@ void Sca::checkChannelSet()
   if (mLink.linkId == -1) {
     BOOST_THROW_EXCEPTION(ScaException() << ErrorInfo::Message("No SCA channel selected"));
   }
+
+  uint32_t channel = (barRead(sc_regs::SWT_MON.index) >> 8) & 0xff;
+
+  if (channel != mLink.linkId) {
+    setChannel(mLink.linkId);
+  }
 }
 
 Sca::CommandData Sca::executeCommand(uint32_t command, uint32_t data, bool lock)
@@ -253,14 +259,11 @@ std::vector<std::pair<Sca::Operation, Sca::Data>> Sca::executeSequence(const std
     mLlaSession->start();
   }
 
-  // force set the channel within the atomic part of the sequence
-  // to be changed as soon as FW provides set channel
   try {
     checkChannelSet();
   } catch (const ScaException& e) {
     return { { Operation::Error, e.what() } };
   }
-  setChannel(mLink.linkId);
 
   std::vector<std::pair<Sca::Operation, Sca::Data>> ret;
   for (const auto& it : operations) {

src/Swt.cxx

@@ -44,7 +44,6 @@ namespace sc_regs = AliceO2::roc::Cru::ScRegisters;
 
 Swt::Swt(AlfLink link) : mBar2(link.bar), mLink(link)
 {
-  setChannel(mLink.linkId); // TODO: Decouple this from the class?
   mLlaSession = std::make_unique<LlaSession>("DDT", link.cardSequence);
 }
 
@@ -73,10 +72,6 @@ void Swt::init(const roc::Parameters::CardIdType& cardId, int linkId)
   };
 
   mLlaSession = std::make_unique<LlaSession>("DDT", card.sequenceId);
-
-  if (mLink.linkId != -1) {
-    setChannel(mLink.linkId);
-  }
 }
 
 void Swt::setChannel(int gbtChannel)
@@ -97,6 +92,12 @@ void Swt::checkChannelSet()
   if (mLink.linkId == -1) {
     BOOST_THROW_EXCEPTION(SwtException() << ErrorInfo::Message("No SWT channel selected"));
   }
+
+  uint32_t channel = (barRead(sc_regs::SWT_MON.index) >> 8) & 0xff;
+
+  if (channel != mLink.linkId) {
+    setChannel(mLink.linkId);
+  }
 }
 
 std::vector<SwtWord> Swt::read(SwtWord::Size wordSize, TimeOut msTimeOut)
@@ -189,14 +190,11 @@ std::vector<std::pair<Swt::Operation, Swt::Data>> Swt::executeSequence(std::vect
     mLlaSession->start();
   }
 
-  // force set the channel within the atomic part of the sequence
-  // to be changed as soon as FW provides set channel
   try {
     checkChannelSet();
   } catch (const SwtException& e) {
     return { { Operation::Error, e.what() } };
   }
-  setChannel(mLink.linkId);
 
   std::vector<std::pair<Operation, Data>> ret;