From a508ab1ac843c5a60a134bf3cdc8837aee6b8ccc Mon Sep 17 00:00:00 2001 From: Adrian Schmutzler Date: Thu, 5 Mar 2020 12:41:51 +0100 Subject: [PATCH] ramips: increase spi-max-frequency to 50 MHz for D-Link DIR-810L Read times drop when increasing frequency to 25 MHz and 50 MHz, but not in between or for further increase. So, use 50 MHz as the lowest frequency with the fastest speed. Test results (thanks to Roger): The device reports a mx25l6405d flash chip. I tried all the maximum values in the devices' datasheet (Table 10. AC CHARACTERISTICS). All of them worked with and without "m25p,fast-read": > 10 MHz root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 1m 33.00s user 0m 0.01s sys 1m 7.56s > 25 MHz root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 34.42s user 0m 0.02s sys 0m 23.58s > 25 MHz, fast read root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 34.45s user 0m 0.02s sys 0m 23.59s > 33 MHz root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 34.39s user 0m 0.00s sys 0m 23.60s > 33 MHz, fast read root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 34.46s user 0m 0.01s sys 0m 23.62s > 50 MHz root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 26.81s user 0m 0.01s sys 0m 18.25s > 50 MHz, fast read root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 26.84s user 0m 0.00s sys 0m 18.25s > 66 MHz root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 26.80s user 0m 0.01s sys 0m 18.23s > 66 MHz, fast read root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 26.80s user 0m 0.02s sys 0m 18.23s > 86 MHz root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 26.84s user 0m 0.01s sys 0m 18.24s > 86 MHz, fast read root@OpenWrt:~# time cat /dev/mtd* > /dev/null real 0m 26.80s user 0m 0.02s sys 0m 18.23s Signed-off-by: Adrian Schmutzler Tested-by: Roger Pueyo Centelles --- target/linux/ramips/dts/mt7620a_dlink_dir-810l.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/target/linux/ramips/dts/mt7620a_dlink_dir-810l.dts b/target/linux/ramips/dts/mt7620a_dlink_dir-810l.dts index 514e9cc354..0a22eee3b5 100644 --- a/target/linux/ramips/dts/mt7620a_dlink_dir-810l.dts +++ b/target/linux/ramips/dts/mt7620a_dlink_dir-810l.dts @@ -59,7 +59,7 @@ flash@0 { compatible = "jedec,spi-nor"; reg = <0>; - spi-max-frequency = <10000000>; + spi-max-frequency = <50000000>; partitions { compatible = "fixed-partitions";