add regfile link

diff --git a/3d_gpu/architecture/regfile.mdwn b/3d_gpu/architecture/regfile.mdwn
index 551d54a16d7ca0f9b52fe5df8ebb74c80c5e0a43..4ea2234d99178e93c3b9857352a76fe1dc5e20c1 100644 (file)
--- a/3d_gpu/architecture/regfile.mdwn
+++ b/3d_gpu/architecture/regfile.mdwn
@@ -1,6 +1,10 @@
 # Register Files
 
-A minimum of 3 register files are required for POWER:
+Discussion:
+
+* <http://lists.libre-riscv.org/pipermail/libre-riscv-dev/2020-June/008368.html>
+
+A minimum of 4 register files are required for POWER:
 
 * Floating-point
 * Integer