From: Michael Lyle <mlyle@lyle.org>
Date: Sun, 30 Oct 2022 04:00:41 +0000 (-0700)
Subject: ramips: gl-mt1300: downclock SPI to 50MHz
X-Git-Tag: v22.03.3~158
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=9155d405130041e9abaf1fcbc03dd7f6746a1fc9;p=openwrt%2Fstaging%2Fhauke.git

ramips: gl-mt1300: downclock SPI to 50MHz

The SPI max frequency was set to 80MHz, considerably higher than the
vendor clocks it in their firmware (10MHz).  Multiple users reported
jffs2 corruption/instability in GitHub issue #10461.

My unit has a W25Q256; datasheet specifies maximum SPI frequency for
read command of 50MHz.

Thanks to @DragonBlueP for suggesting to eliminate m25p,fast-read;
and @MPannen1979 for identifying the problem.

Fixes: #10461
Signed-off-by: Michael Lyle <mlyle@lyle.org>
(cherry picked from commit 961e01fc67e7d9e60557df3474fa326216aa4839)
---

diff --git a/target/linux/ramips/dts/mt7621_glinet_gl-mt1300.dts b/target/linux/ramips/dts/mt7621_glinet_gl-mt1300.dts
index 384da1bfa9..7e3dc8cc03 100644
--- a/target/linux/ramips/dts/mt7621_glinet_gl-mt1300.dts
+++ b/target/linux/ramips/dts/mt7621_glinet_gl-mt1300.dts
@@ -67,8 +67,7 @@
 	flash@0 {
 		compatible = "jedec,spi-nor";
 		reg = <0>;
-		spi-max-frequency = <80000000>;
-		m25p,fast-read;
+		spi-max-frequency = <50000000>;
 		broken-flash-reset;
 
 		partitions {