ramips: increase SPI frequency for ASUS RT-AC51U/RT-AC54U
This increases the SPI frequency for both ASUS RT-AC51U and RT-AC54U.
Speed comparison tests have been performed on RT-AC54U:
- 10Mhz
root@OpenWrt:~# time cat /dev/mtd* > /dev/null
real 4m 37.78s
user 0m 0.02s
sys 2m 43.92s
- 50Mhz
root@OpenWrt:~# time cat /dev/mtd* > /dev/null
real 1m 28.34s
user 0m 0.03s
sys 0m 46.96s
- 50Mhz fast read
root@OpenWrt:~# time cat /dev/mtd* > /dev/null
real 1m 11.94s
user 0m 0.01s
sys 0m 46.94s
- 80Mhz
root@OpenWrt:~# time cat /dev/mtd* > /dev/null
real 1m 12.31s
user 0m 0.04s
sys 0m 46.96s
- 80Mhz fast read
root@OpenWrt:~# time cat /dev/mtd* > /dev/null
real 1m 12.15s
user 0m 0.02s
sys 0m 46.97s
Based on that, we took 50 MHz with fast-read, as higher frequencies
didn't yield further improvements.
For the RT-AC51U, only the final configuration was tested.
Tested-by: Zhijun You <[email protected]> [RT-AC54U]
Tested-by: Davide Fioravanti <[email protected]> [RT-AC51U]
Signed-off-by: Adrian Schmutzler <[email protected]>
Adrian Schmutzler