From 105e648d92ea5eea266a0f51a177d0a2139bacb1 Mon Sep 17 00:00:00 2001
From: Mateusz Faderewski <sc@mateuszfaderewski.pl>
Date: Sun, 20 Aug 2023 22:03:14 +0200
Subject: [PATCH] Reboot: reset RDRAM before putting it in standby mode

---
 src/boot/reboot.S | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/boot/reboot.S b/src/boot/reboot.S
index fabfa644..ef716650 100644
--- a/src/boot/reboot.S
+++ b/src/boot/reboot.S
@@ -6,10 +6,11 @@
 #define RI_SELECT           0x0C
 #define RI_REFRESH          0x10
 #define RI_LATENCY          0x14
-#define RI_RERROR           0x18
-#define RI_WERROR           0x1C
 
-#define RI_MODE_RESET       0x0000000E
+#define RI_MODE_RESET       0x0000000C
+#define RI_MODE_STANDBY     0x0000000E
+
+#define RDRAM_RESET_DELAY   1024
 
 #define IPL3_ENTRY          0xA4000040
 
@@ -49,6 +50,14 @@ reset_rdram:
     sw $zero, RI_SELECT($t0)
     sw $zero, RI_REFRESH($t0)
 
+    li $t2, RDRAM_RESET_DELAY
+delay:
+    addiu $t2, $t2, (-1)
+    bnez $t2, delay
+
+    li $t1, RI_MODE_STANDBY
+    sw $t1, RI_MODE($t0)
+
 run_ipl3:
     li $t3, IPL3_ENTRY
     jr $t3