Another attempt to support configuration TGs and polyphony (#690)

* Initial commit for configuration TGs and polyphony across RPI1-5.

* Ensure unused TGs in a performance are MIDI disabled.  Set polyphony to higher defaults on Pi 4 and 5.

* Actually, can just default to MIDI "disabled" directly in performance config if not present.

* Fix issue with choosing max polyphony

src/config.cpp

@@ -36,6 +36,20 @@ void CConfig::Load (void)
 {
 	m_Properties.Load ();
 
+	// Number of Tone Generators and Polyphony
+	m_nToneGenerators = m_Properties.GetNumber ("ToneGenerators", DefToneGenerators);
+	m_nPolyphony = m_Properties.GetNumber ("Polyphony", DefaultNotes);
+	// At present there are only two options for tone generators: min or max
+	// and for the Pi 1,2,3 these are the same anyway.
+	if ((m_nToneGenerators != MinToneGenerators) && (m_nToneGenerators != AllToneGenerators))
+	{
+		m_nToneGenerators = DefToneGenerators;
+	}
+	if (m_nPolyphony > MaxNotes)
+	{
+		m_nPolyphony = DefaultNotes;
+	}
+
 	m_bUSBGadget = m_Properties.GetNumber ("USBGadget", 0) != 0;
 	m_nUSBGadgetPin = m_Properties.GetNumber ("USBGadgetPin", 0); // Default OFF
 	SetUSBGadgetMode(m_bUSBGadget); // Might get overriden later by USBGadgetPin state
@@ -177,6 +191,48 @@ void CConfig::Load (void)
 	m_bPerformanceSelectChannel = m_Properties.GetNumber ("PerformanceSelectChannel", 0);
 }
 
+unsigned CConfig::GetToneGenerators (void) const
+{
+	return m_nToneGenerators;
+}
+
+unsigned CConfig::GetPolyphony (void) const
+{
+	return m_nPolyphony;
+}
+
+unsigned CConfig::GetTGsCore1 (void) const
+{
+#ifndef ARM_ALLOW_MULTI_CORE
+	return 0;
+#else
+	if (m_nToneGenerators > MinToneGenerators)
+	{
+		return TGsCore1 + TGsCore1Opt;
+	}
+	else
+	{
+		return TGsCore1;
+	}
+#endif
+}
+
+unsigned CConfig::GetTGsCore23 (void) const
+{
+#ifndef ARM_ALLOW_MULTI_CORE
+	return 0;
+#else
+	if (m_nToneGenerators > MinToneGenerators)
+	{
+		return TGsCore23 + TGsCore23Opt;
+	}
+	else
+	{
+		return TGsCore23;
+	}
+#endif
+}
+
 bool CConfig::GetUSBGadget (void) const
 {
 	return m_bUSBGadget;

src/config.h

@@ -35,18 +35,49 @@
 class CConfig		// Configuration for MiniDexed
 {
 public:
+// Set maximum, minimum and default numbers of tone generators, depending on Pi version.
+// Actual number in can be changed via config settings for some Pis.
 #ifndef ARM_ALLOW_MULTI_CORE
-	static const unsigned ToneGenerators = 1;
+	// Pi V1 or Zero (single core)
+	static const unsigned MinToneGenerators = 1;
+	static const unsigned AllToneGenerators = 1;
+	static const unsigned DefToneGenerators = AllToneGenerators;
 #else
+#if (RASPPI==4 || RASPPI==5)
+	// Pi 4 and 5 quad core
+	// These are max values, default is to support 8 in total with optional 16 TGs
 	static const unsigned TGsCore1 = 2;		// process 2 TGs on core 1
 	static const unsigned TGsCore23 = 3;		// process 3 TGs on core 2 and 3 each
-	static const unsigned ToneGenerators = TGsCore1 + 2*TGsCore23;
+	static const unsigned TGsCore1Opt = 2;		// process optional additional 2 TGs on core 1
+	static const unsigned TGsCore23Opt = 3;		// process optional additional 3 TGs on core 2 and 3 each
+	static const unsigned MinToneGenerators = TGsCore1 + 2*TGsCore23;
+	static const unsigned AllToneGenerators = TGsCore1 + TGsCore1Opt + 2*TGsCore23 + 2*TGsCore23Opt;
+	static const unsigned DefToneGenerators = MinToneGenerators;
+#else
+	// Pi 2 or 3 quad core
+	static const unsigned TGsCore1 = 2;		// process 2 TGs on core 1
+	static const unsigned TGsCore23 = 3;		// process 3 TGs on core 2 and 3 each
+	static const unsigned TGsCore1Opt = 0;
+	static const unsigned TGsCore23Opt = 0;
+	static const unsigned MinToneGenerators = TGsCore1 + 2*TGsCore23;
+	static const unsigned AllToneGenerators = MinToneGenerators;
+	static const unsigned DefToneGenerators = AllToneGenerators;
 #endif
-
+#endif
+
+// Set maximum polyphony, depending on PI version.  This can be changed via config settings
 #if RASPPI == 1
-	static const unsigned MaxNotes = 8;		// polyphony
+	static const unsigned MaxNotes = 8;
+	static const unsigned DefaultNotes = 8;
+#elif RASPPI == 4
+	static const unsigned MaxNotes = 32;
+	static const unsigned DefaultNotes = 24;
+#elif RASPPI == 5
+	static const unsigned MaxNotes = 32;
+	static const unsigned DefaultNotes = 32;
 #else
 	static const unsigned MaxNotes = 16;
+	static const unsigned DefaultNotes = 16;
 #endif
 
 	static const unsigned MaxChunkSize = 4096;
@@ -67,6 +98,12 @@ class CConfig		// Configuration for MiniDexed
 
 	void Load (void);
 
+	// TGs and Polyphony
+	unsigned GetToneGenerators (void) const;
+	unsigned GetPolyphony (void) const;
+	unsigned GetTGsCore1 (void) const;
+	unsigned GetTGsCore23 (void) const;
+
 	// USB Mode
 	bool GetUSBGadget (void) const;
 	unsigned GetUSBGadgetPin (void) const;
@@ -195,6 +232,9 @@ class CConfig		// Configuration for MiniDexed
 private:
 	CPropertiesFatFsFile m_Properties;
 
+	unsigned m_nToneGenerators;
+	unsigned m_nPolyphony;
+
 	bool m_bUSBGadget;
 	unsigned m_nUSBGadgetPin;
 	bool m_bUSBGadgetMode;

src/mididevice.cpp

@@ -65,7 +65,7 @@ CMIDIDevice::CMIDIDevice (CMiniDexed *pSynthesizer, CConfig *pConfig, CUserInter
 	m_pConfig (pConfig),
 	m_pUI (pUI)
 {
-	for (unsigned nTG = 0; nTG < CConfig::ToneGenerators; nTG++)
+	for (unsigned nTG = 0; nTG < CConfig::AllToneGenerators; nTG++)
 	{
 		m_ChannelMap[nTG] = Disabled;
 	}
@@ -78,13 +78,13 @@ CMIDIDevice::~CMIDIDevice (void)
 
 void CMIDIDevice::SetChannel (u8 ucChannel, unsigned nTG)
 {
-	assert (nTG < CConfig::ToneGenerators);
+	assert (nTG < CConfig::AllToneGenerators);
 	m_ChannelMap[nTG] = ucChannel;
 }
 
 u8 CMIDIDevice::GetChannel (unsigned nTG) const
 {
-	assert (nTG < CConfig::ToneGenerators);
+	assert (nTG < CConfig::AllToneGenerators);
 	return m_ChannelMap[nTG];
 }
 
@@ -238,8 +238,8 @@ void CMIDIDevice::MIDIMessageHandler (const u8 *pMessage, size_t nLength, unsign
 			break;
 		}
 
-		// Process MIDI for each Tone Generator
-		for (unsigned nTG = 0; nTG < CConfig::ToneGenerators; nTG++)
+		// Process MIDI for each active Tone Generator
+		for (unsigned nTG = 0; nTG < m_pConfig->GetToneGenerators(); nTG++)
 		{
 			if (ucStatus == MIDI_SYSTEM_EXCLUSIVE_BEGIN)
 			{

src/mididevice.h

@@ -65,7 +65,7 @@ class CMIDIDevice
 	CConfig *m_pConfig;
 	CUserInterface *m_pUI;
 
-	u8 m_ChannelMap[CConfig::ToneGenerators];
+	u8 m_ChannelMap[CConfig::AllToneGenerators];
 
 	std::string m_DeviceName;