[openwrt/openwrt] ramips: gl-mt1300: downclock SPI to 50MHz

[LEDE Commits]

hauke pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/961e01fc67e7d9e60557df3474fa326216aa4839

commit 961e01fc67e7d9e60557df3474fa326216aa4839
Author: Michael Lyle <mlyle at lyle.org>
AuthorDate: Sat Oct 29 21:00:41 2022 -0700

    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 at lyle.org>
---
 target/linux/ramips/dts/mt7621_glinet_gl-mt1300.dts | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/target/linux/ramips/dts/mt7621_glinet_gl-mt1300.dts b/target/linux/ramips/dts/mt7621_glinet_gl-mt1300.dts
index a332a87a57..d5440b3a51 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 at 0 {
 		compatible = "jedec,spi-nor";
 		reg = <0>;
-		spi-max-frequency = <80000000>;
-		m25p,fast-read;
+		spi-max-frequency = <50000000>;
 		broken-flash-reset;
 
 		partitions {