Add Avalon-MM emulator

1 files changed, 62 insertions, 0 deletions

diff --git a/tb/avalon.impl.hpp b/tb/avalon.impl.hpp
new file mode 100644
index 0000000..7f589ae
--- /dev/null
+++ b/tb/avalon.impl.hpp
@@ -0,0 +1,62 @@
+#ifndef AVALON_IMPL_HPP
+#define AVALON_IMPL_HPP
+
+#include <cassert>
+#include <cstdio>
+
+namespace taller::avalon
+{
+	template<class Platform>
+	void interconnect<Platform>::attach(slave &dev)
+	{
+		devices.push_back(binding { dev.base_address(), dev.address_mask(), dev });
+	}
+
+	template<class Platform>
+	void interconnect<Platform>::tick()
+	{
+		auto addr = plat.avl_address;
+		if(!active)
+		{
+			if(addr & 0b11)
+			{
+				fprintf(stderr, "[avl] unaligned address: 0x%08x\n", addr);
+				assert(false);
+			}
+
+			for(auto &binding : devices)
+			{
+				if((addr & binding.mask) == binding.base)
+				{
+					active = &binding.dev;
+					break;
+				}
+			}
+
+			if(!active)
+			{
+				const char *op = plat.avl_read ? "read" : "write";
+				fprintf(stderr, "[avl] attempt to %s memory hole at 0x%08x\n", op, addr);
+				assert(false);
+			}
+		}
+
+		assert(!plat.avl_read || !plat.avl_write);
+		auto pos = addr >> 2;
+
+		if(plat.avl_read)
+		{
+			plat.avl_waitrequest = !active->read(pos, plat.avl_readdata);
+		} else if(plat.avl_write)
+		{
+			plat.avl_waitrequest = !active->write(pos, plat.avl_writedata, plat.avl_byteenable);
+		}
+
+		if(!plat.avl_waitrequest)
+		{
+			active = nullptr;
+		}
+	}
+}
+
+#endif