From a95cd423cc1320968a678ab0c01fd7471e133940 Mon Sep 17 00:00:00 2001
From: Florent Kermarrec <florent@enjoy-digital.fr>
Date: Fri, 9 Mar 2018 18:53:57 +0100
Subject: [PATCH] libboard/sdram: add gap for write leveling

---
 artiq/firmware/libboard/sdram.rs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/artiq/firmware/libboard/sdram.rs b/artiq/firmware/libboard/sdram.rs
index 246b51fff..a42e5c668 100644
--- a/artiq/firmware/libboard/sdram.rs
+++ b/artiq/firmware/libboard/sdram.rs
@@ -132,6 +132,12 @@ mod ddr {
                     if !incr_delay() { break }
                     dq = ptr::read_volatile(dq_addr);
                 }
+
+                // Get a bit further into the 0 zone
+                #[cfg(kusddrphy)]
+                for _ in 0..32 {
+                    incr_delay();
+                }
             }
 
             while dq == 0 {