1 files changed, 102 insertions, 8 deletions

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();
+		}
+	}
 }