Implement JTAG-UART tx emulation

3 files changed, 83 insertions, 0 deletions

diff --git a/tb/jtag_uart.cpp b/tb/jtag_uart.cpp
new file mode 100644
index 0000000..78d438e
--- /dev/null
+++ b/tb/jtag_uart.cpp
@@ -0,0 +1,55 @@
+#include "avalon.hpp"
+#include "jtag_uart.hpp"
+
+namespace taller::avalon
+{
+	jtag_uart::jtag_uart(std::uint32_t base) noexcept
+	: slave(base, 8, 4)
+	{}
+
+	bool jtag_uart::read(std::uint32_t addr, std::uint32_t &data) noexcept
+	{
+		switch(addr)
+		{
+			case 0:
+				data = 0; //TODO
+				break;
+
+			case 1:
+				data =
+					  static_cast<std::uint32_t>(ctrl_re) << 0
+					| static_cast<std::uint32_t>(ctrl_we) << 1
+					//TODO: varios bits
+					| static_cast<std::uint32_t>(ctrl_ac) << 10
+					//TODO: disponibilidad de tx fifo
+					| static_cast<std::uint32_t>(255) << 10;
+
+				break;
+		}
+
+		return true;
+	}
+
+	bool jtag_uart::write(std::uint32_t addr, std::uint32_t data, unsigned byte_enable) noexcept
+	{
+		switch(addr)
+		{
+			case 0:
+				putchar(data & 0xff);
+				ctrl_ac = 1;
+				break;
+
+			case 1:
+				ctrl_re = !!(data & (1 << 0));
+				ctrl_we = !!(data & (1 << 1));
+				if(!!(data & (1 << 10)))
+				{
+					ctrl_ac = 0;
+				}
+
+				break;
+		}
+
+		return true;
+	}
+}
diff --git a/tb/jtag_uart.hpp b/tb/jtag_uart.hpp
new file mode 100644
index 0000000..6db50f8
--- /dev/null
+++ b/tb/jtag_uart.hpp
@@ -0,0 +1,25 @@
+#ifndef TALLER_JTAG_UART_HPP
+#define TALLER_JTAG_UART_HPP
+
+#include <cstdint>
+
+#include "avalon.hpp"
+
+namespace taller::avalon
+{
+	class jtag_uart : public slave
+	{
+		public:
+			jtag_uart(std::uint32_t base) noexcept;
+
+			virtual bool read(std::uint32_t addr, std::uint32_t &data) noexcept final override;
+			virtual bool write(std::uint32_t addr, std::uint32_t data, unsigned byte_enable) noexcept final override;
+
+		private:
+			bool ctrl_re = false;
+			bool ctrl_we = false;
+			bool ctrl_ac = true;
+	};
+}
+
+#endif
diff --git a/tb/top/conspiracion.cpp b/tb/top/conspiracion.cpp
index 2840b15..789a0df 100644
--- a/tb/top/conspiracion.cpp
+++ b/tb/top/conspiracion.cpp
@@ -22,6 +22,7 @@
 
 #include "../avalon.hpp"
 #include "../mem.hpp"
+#include "../jtag_uart.hpp"
 #include "../null.hpp"
 #include "../window.hpp"
 #include "../vga.hpp"
@@ -197,6 +198,7 @@ int main(int argc, char **argv)
 	interconnect<Vconspiracion_vga_domain> avl_vga(*top.conspiracion->plat->vga);
 
 	mem<std::uint32_t> hps_ddr3(0x0000'0000, 512 << 20);
+	jtag_uart ttyj0(0x3000'0000);
 	mem<std::uint16_t> vram(0x3800'0000, 64 << 20);
 	null vram_null(0x3800'0000, 64 << 20, 2);
 	window vram_window(vram, 0x0000'0000);
@@ -205,6 +207,7 @@ int main(int argc, char **argv)
 	bool enable_video = !headless;
 
 	avl.attach(hps_ddr3);
+	avl.attach(ttyj0);
 
 	if(enable_video)
 	{