Implement JTAG-UART input

5 files changed, 137 insertions, 14 deletions

diff --git a/tb/interval_timer.cpp b/tb/interval_timer.cpp
index f593894..f790030 100644
--- a/tb/interval_timer.cpp
+++ b/tb/interval_timer.cpp
@@ -1,3 +1,5 @@
+#include <cstdint>
+
 #include "avalon.hpp"
 #include "interval_timer.hpp"
 
diff --git a/tb/jtag_uart.cpp b/tb/jtag_uart.cpp
index 78d438e..3bef42e 100644
--- a/tb/jtag_uart.cpp
+++ b/tb/jtag_uart.cpp
@@ -1,3 +1,7 @@
+#include <cstdint>
+
+#include <ncursesw/ncurses.h>
+
 #include "avalon.hpp"
 #include "jtag_uart.hpp"
 
@@ -7,22 +11,87 @@ namespace taller::avalon
 	: slave(base, 8, 4)
 	{}
 
+	jtag_uart::~jtag_uart() noexcept
+	{
+		release();
+	}
+
+	void jtag_uart::tick() noexcept
+	{
+		if(!took_over || rx_avail == sizeof rx)
+		{
+			return;
+		}
+
+		if(countdown > 0)
+		{
+			--countdown;
+			return;
+		}
+
+		countdown = 10'000;
+
+		int input = getch();
+		if(input != ERR)
+		{
+			unsigned index = rx_next + rx_avail;
+			if(index >= sizeof rx)
+			{
+				index -= sizeof rx;
+			}
+
+			rx[index] = input;
+			++rx_avail;
+		}
+
+		ctrl_ac = 1;
+	}
+
 	bool jtag_uart::read(std::uint32_t addr, std::uint32_t &data) noexcept
 	{
+		bool valid_read;
+		bool ctrl_ri;
+		bool ctrl_wi;
+		bool ctrl_rrdy;
+
+		std::uint8_t read;
+
 		switch(addr)
 		{
 			case 0:
-				data = 0; //TODO
+				read = rx[rx_next];
+				valid_read = rx_avail > 0;
+
+				if(valid_read)
+				{
+					--rx_avail;
+					rx_next = rx_next + 1 < sizeof rx ? rx_next + 1 : 0;
+				}
+
+				data
+					= rx_avail   << 16
+					| valid_read << 15
+					| (read & 0xff);
+
 				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;
+				ctrl_ri = ctrl_re && rx_avail > 0;
+
+				// Siempre se puede escribir
+				ctrl_wi = ctrl_we;
+
+				// Este bit no existe pero U-Boot lo espera por alguna razón
+				ctrl_rrdy = rx_avail > 0;
+
+				data
+					= ctrl_re   << 0
+					| ctrl_we   << 1
+					| ctrl_ri   << 8
+					| ctrl_wi   << 9
+					| ctrl_ac   << 10
+					| ctrl_rrdy << 12
+					| 63        << 16;
 
 				break;
 		}
@@ -36,6 +105,8 @@ namespace taller::avalon
 		{
 			case 0:
 				putchar(data & 0xff);
+				fflush(stdout);
+
 				ctrl_ac = 1;
 				break;
 
@@ -52,4 +123,27 @@ namespace taller::avalon
 
 		return true;
 	}
+
+	void jtag_uart::takeover() noexcept
+	{
+		if(took_over)
+		{
+			return;
+		}
+
+		assert(::initscr() != nullptr);
+		assert(::noecho() != ERR);
+		assert(::nodelay(stdscr, TRUE) != ERR);
+		assert(::cbreak() != ERR);
+
+		took_over = true;
+	}
+
+	void jtag_uart::release() noexcept
+	{
+		if(took_over)
+		{
+			::endwin();
+		}
+	}
 }
diff --git a/tb/jtag_uart.hpp b/tb/jtag_uart.hpp
index 6db50f8..3c378c3 100644
--- a/tb/jtag_uart.hpp
+++ b/tb/jtag_uart.hpp
@@ -11,14 +11,25 @@ namespace taller::avalon
 	{
 		public:
 			jtag_uart(std::uint32_t base) noexcept;
+			~jtag_uart() noexcept;
+
+			void tick() 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;
 
+			void takeover() noexcept;
+			void release() noexcept;
+
 		private:
-			bool ctrl_re = false;
-			bool ctrl_we = false;
-			bool ctrl_ac = true;
+			unsigned     countdown = 0;
+			unsigned     rx_avail  = 0;
+			unsigned     rx_next   = 0;
+			bool         ctrl_re   = false;
+			bool         ctrl_we   = false;
+			bool         ctrl_ac   = true;
+			bool         took_over = false;
+			std::uint8_t rx[64];
 	};
 }
 
diff --git a/tb/sim/sim.py b/tb/sim/sim.py
index b14e0fd..91fc348 100755
--- a/tb/sim/sim.py
+++ b/tb/sim/sim.py
@@ -249,7 +249,7 @@ mem_dumps = module_get('mem_dumps', [])
 if init := module_get('init'):
     init()
 
-exec_args = [verilated, '--headless', '--cycles', str(cycles), '--dump-regs']
+exec_args = [verilated, '--headless', '--no-tty', '--cycles', str(cycles), '--dump-regs']
 
 for rng in mem_dumps:
     length = rng.stop - rng.start
diff --git a/tb/top/conspiracion.cpp b/tb/top/conspiracion.cpp
index d710bde..bf0ee89 100644
--- a/tb/top/conspiracion.cpp
+++ b/tb/top/conspiracion.cpp
@@ -192,6 +192,11 @@ int main(int argc, char **argv)
 		parser, "headless", "Disable video output", {"headless"}
 	);
 
+	args::Flag no_tty
+	(
+		parser, "no-tty", "Disable TTY takeoveer", {"no-tty"}
+	);
+
 	args::ValueFlag<unsigned> cycles
 	(
 		parser, "cycles", "Number of core cycles to run", {"cycles"}, 256
@@ -251,7 +256,7 @@ 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);
+	jtag_uart ttyJ0(0x3000'0000);
 	interval_timer timer(0x3002'0000);
 	mem<std::uint32_t> vram(0x3800'0000, 64 << 20);
 	null vram_null(0x3800'0000, 64 << 20, 2);
@@ -267,7 +272,7 @@ int main(int argc, char **argv)
 	bool enable_video = !headless;
 
 	avl.attach(hps_ddr3);
-	avl.attach(ttyj0);
+	avl.attach(ttyJ0);
 	avl.attach(timer);
 
 	for(auto &slave : consts)
@@ -334,6 +339,7 @@ int main(int argc, char **argv)
 
 		if(top.clk_clk)
 		{
+			ttyJ0.tick();
 			timer.tick();
 		}
 
@@ -364,6 +370,11 @@ int main(int argc, char **argv)
 		tick();
 	};
 
+	if(!no_tty)
+	{
+		ttyJ0.takeover();
+	}
+
 	top.halt = 0;
 	top.rst_n = 0;
 	cycle();
@@ -378,6 +389,11 @@ int main(int argc, char **argv)
 		}
 	}
 
+	if(!no_tty)
+	{
+		ttyJ0.release();
+	}
+
 	if(enable_trace)
 	{
 		trace.close();