starvation seems to work

+ With the limitation that a grid node can only attempt one move per
  clock, which *seems* to be the easiest strategy to implement in hardware,
  but I should try experimenting with more complex routing/priority
  assignment schemes to speed up the system overall

1 files changed, 46 insertions, 0 deletions

diff --git a/tests/starved_grid/test.c b/tests/starved_grid/test.c
new file mode 100644
index 0000000..c91868c
--- /dev/null
+++ b/tests/starved_grid/test.c
@@ -0,0 +1,46 @@
+#define X 16
+#define Y 16
+
+void _start(unsigned short x, unsigned short y)
+{
+	volatile unsigned long *counter = (unsigned long *)((unsigned long)1 << 48);
+	volatile char *uart = (char *)4096;
+
+	/* very hacky, not recommended but good enough for testing */
+	if (x == 0 && y == 2) {
+		*counter = 0;
+		*uart = '0';
+		*uart = '\n';
+	}
+	else
+		while (*counter != (((unsigned long)x << 16) | y))
+			;
+
+	*uart = '(';
+	/* [0 - 16] as two octal numbers */
+	*uart = ((x >> 3) & 0x7) + '0';
+	*uart = ((x >> 0) & 0x7) + '0';
+
+	*uart = ',';
+	*uart = ' ';
+
+	*uart = ((y >> 3) & 0x7) + '0';
+	*uart = ((y >> 0) & 0x7) + '0';
+
+	*uart = ')';
+	*uart = '\n';
+
+	if (x == 15 && y == 15)
+		asm ("ebreak\n");
+
+	if (y == 15) {
+		x++;
+		y = 0;
+	}
+	else
+		y++;
+
+	*counter = ((unsigned long)x << 16) | y;
+	while (1)
+		;
+}