Can freeze boot in order to load firmware via SWD/JTAG

4ms · Jul 26, 2023 · a704494 · a704494
1 parent f8b13d4
commit a704494
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diff --git a/src/board_conf/osd32brk_conf.hh b/src/board_conf/osd32brk_conf.hh
@@ -22,6 +22,11 @@ constexpr PinConf UartTX{GPIO::G, PinNum::_11, PinAF::AF_6};
 constexpr PinConf BootSelectPin{GPIO::B, PinNum::_6};
 constexpr bool UseBootSelect = false;
 
+// Freeze mode: halts booting after initializing everything
+// so you can load firmware via SWD/JTAG
+constexpr bool UseFreezePin = false;
+constexpr PinConf FreezePin{GPIO::Unused, PinNum::_0};
+
 namespace NORFlash
 {
 constexpr bool HasNORFlash = false;

diff --git a/src/board_conf/stm32disco_conf.hh b/src/board_conf/stm32disco_conf.hh
@@ -25,6 +25,11 @@ using GreenLED2 = BlueLED; // For compatibility with OSD32BRK board
 constexpr bool UseBootSelect = false;
 constexpr PinConf BootSelectPin{GPIO::A, PinNum::_13};
 
+// Freeze mode: halts booting after initializing everything
+// so you can load firmware via SWD/JTAG
+constexpr bool UseFreezePin = false;
+constexpr PinConf FreezePin{GPIO::Unused, PinNum::_0};
+
 constexpr uint32_t ConsoleUART = UART4_BASE;
 constexpr PinConf UartRX{GPIO::B, PinNum::_2, PinAF::AF_8};
 constexpr PinConf UartTX{GPIO::G, PinNum::_11, PinAF::AF_6};

diff --git a/src/main.cc b/src/main.cc
@@ -45,6 +45,18 @@ void main()
 
 	BootLoader::LoadTarget image_type = BootLoader::LoadTarget::App;
 
+	if constexpr (Board::UseFreezePin) {
+		Board::FreezePin.init(PinMode::Input, PinPull::Up);
+		// delay to allow pull-up to settle
+		udelay(1000);
+		if (!Board::FreezePin.read()) {
+			print("Freeze pin detected active, freezing.\n");
+			print("Ready to load firmware to DDR RAM via SWD/JTAG.\n");
+			while (true)
+				;
+		}
+	}
+
 	// Check Boot Select pin
 	if constexpr (Board::UseBootSelect) {
 		Board::BootSelectPin.init(PinMode::Input, PinPull::Up);