Very early initial support for RPi 5 based on dev branch of circle. (#638)

* Very early initial support for RPi 5 based on dev branch of circle.

* Added parameter to choose UART option on all RPi versions to be GP14/15

* Build for Raspberry Pi 5

* Update README.md for RPi 5

---------

Co-authored-by: probonopd <probonopd@users.noreply.github.com>

.github/workflows/build.yml

@@ -27,6 +27,12 @@ jobs:
            wget -q https://developer.arm.com/-/media/Files/downloads/gnu-a/10.3-2021.07/binrel/gcc-arm-10.3-2021.07-x86_64-arm-none-eabi.tar.xz
            tar xf *-arm-none-eabi.tar.xz
            mkdir -p kernels
+    - name: Build for Raspberry Pi 5
+      run: |
+           set -ex
+           export PATH=$(readlink -f ./gcc-*aarch64-none*/bin/):$PATH
+           RPI=5 bash -ex build.sh
+           cp ./src/kernel*.img ./kernels/
     - name: Build for Raspberry Pi 4
       run: |
            set -ex

README.md

@@ -32,7 +32,8 @@ Video about this project by [Floyd Steinberg](https://www.youtube.com/watch?v=Z3
 
 ## System Requirements
 
-- Raspberry Pi 1, 2, 3, 4, or 400 (Zero and Zero 2 can be used but need HDMI or a supported i2s DAC for audio out). On Raspberry Pi 1 and on Raspberry Pi Zero there will be severely limited functionality (only one tone generator instead of 8)
+- Raspberry Pi 1, 2, 3, 4, or 400. Raspberry Pi Zero and Zero 2 can be used but need HDMI or a supported i2s DAC for audio out. On Raspberry Pi 1 and on Raspberry Pi Zero there will be severely limited functionality (only one tone generator instead of 8)
+- Raspberry Pi 5 can be used but currently support is experimental; HDMI sound and USB Gadget mode are not available yet 
 - A [PCM5102A or PCM5122 based DAC](https://github.com/probonopd/MiniDexed/wiki/Hardware#i2s-dac), HDMI display or [audio extractor](https://github.com/probonopd/MiniDexed/wiki/Hardware#hdmi-to-audio) for good sound quality. If you don't have this, you can use the headphone jack on the Raspberry Pi but on anything but the Raspberry 4 the sound quality will be seriously limited
 - Optionally (but highly recommended), an [LCDC1602 Display](https://www.berrybase.de/en/sensors-modules/displays/alphanumeric-displays/alphanumerisches-lcd-16x2-gr-252-n/gelb) (with or without i2c "backpack" board) and a [KY-040 rotary encoder](https://www.berrybase.de/en/components/passive-components/potentiometer/rotary-encoder/drehregler/rotary-encoder-mit-breakoutboard-ohne-gewinde-und-mutter)
 

src/config.txt

@@ -10,7 +10,7 @@ gpu_mem=16
 disable_overscan=0
 
 #
-# Use 64-bit for RPi 3, 4, 400 and Zero 2, and 32-bit for all other models
+# Use 64-bit for RPi 3, 4, 400, 5 and Zero 2, and 32-bit for all other models
 #
 
 [pi3]
@@ -24,3 +24,7 @@ kernel=kernel8-rpi4.img
 # Zero 2 W
 [pi02]
 arm_64bit=1
+
+[pi5]
+arm_64bit=1
+kernel=kernel_2712.img

src/kernel.cpp

@@ -68,8 +68,12 @@ bool CKernel::Initialize (void)
 	
 	if (m_Config.GetUSBGadgetMode())
 	{
+#if RASPPI==5
+#warning No support for USB Gadget Mode on RPI 5 yet
+#else
 		// Run the USB stack in USB Gadget (device) mode
 		m_pUSB = new CUSBMiniDexedMIDIGadget (&mInterrupt);
+#endif
 	}
 	else
 	{

src/minidexed.cpp

@@ -103,7 +103,11 @@ CMiniDexed::CMiniDexed (CConfig *pConfig, CInterruptSystem *pInterrupt,
 		
 	if (pConfig->GetUSBGadgetMode())
 	{
+#if RASPPI==5
+		LOGNOTE ("USB Gadget (Device) Mode NOT supported on RPI 5");
+#else
 		LOGNOTE ("USB In Gadget (Device) Mode");
+#endif
 	}
 	else
 	{
@@ -128,6 +132,9 @@ CMiniDexed::CMiniDexed (CConfig *pConfig, CInterruptSystem *pInterrupt,
 	}
 	else if (strcmp (pDeviceName, "hdmi") == 0)
 	{
+#if RASPPI==5
+		LOGNOTE ("HDMI mode NOT supported on RPI 5.");
+#else
 		LOGNOTE ("HDMI mode");
 
 		m_pSoundDevice = new CHDMISoundBaseDevice (pInterrupt, pConfig->GetSampleRate (),
@@ -136,6 +143,7 @@ CMiniDexed::CMiniDexed (CConfig *pConfig, CInterruptSystem *pInterrupt,
 		// The channels are swapped by default in the HDMI sound driver.
 		// TODO: Remove this line, when this has been fixed in the driver.
 		m_bChannelsSwapped = !m_bChannelsSwapped;
+#endif
 	}
 	else
 	{

src/serialmididevice.cpp

@@ -28,11 +28,15 @@
 
 LOGMODULE("serialmididevice");
 
+// There are several UART options - see circle/include/serial.h
+// 0 corresponds to GP14/GP15 on all RPi versions.
+#define SERIAL_MIDI_DEVICE 0
+
 CSerialMIDIDevice::CSerialMIDIDevice (CMiniDexed *pSynthesizer, CInterruptSystem *pInterrupt,
 				      CConfig *pConfig, CUserInterface *pUI)
 :	CMIDIDevice (pSynthesizer, pConfig, pUI),
 	m_pConfig (pConfig),
-	m_Serial (pInterrupt, TRUE),
+	m_Serial (pInterrupt, TRUE, SERIAL_MIDI_DEVICE),
 	m_nSerialState (0),
 	m_nSysEx (0),
 	m_SendBuffer (&m_Serial)

src/usbminidexedmidigadget.h

@@ -22,6 +22,23 @@
 #ifndef _usbminidexedmidigadget_h
 #define _usbminidexedmidigadget_h
 
+#if RASPPI==5
+#include <circle/sysconfig.h>
+#include <assert.h>
+
+#warning No support for USB Gadget Mode on RPI 5 yet
+class CUSBMiniDexedMIDIGadget
+{
+public:
+	CUSBMiniDexedMIDIGadget (CInterruptSystem *pInterruptSystem)
+	{
+	}
+
+	~CUSBMiniDexedMIDIGadget (void)
+	{
+	}
+};
+#else
 #include <circle/usb/gadget/usbmidigadget.h>
 #include <circle/usb/gadget/usbmidigadgetendpoint.h>
 #include <circle/sysconfig.h>
@@ -82,5 +99,6 @@ protected:
 		return CUSBMIDIGadget::GetDescriptor(wValue, wIndex, pLength);
 	}
 };
+#endif
 
 #endif

submod.sh

@@ -6,13 +6,13 @@ git submodule update --init --recursive
 #
 # Use fixed master branch of circle-stdlib then re-update
 cd circle-stdlib/
-git checkout 695ab4a
+git checkout 3bd135d
 git submodule update --init --recursive
 cd -
 #
 # Optional update submodules explicitly
 cd circle-stdlib/libs/circle
-git checkout fe09c4b
+git checkout 4b3e06f
 cd -
 cd circle-stdlib/libs/circle-newlib
 #git checkout develop