riscv: dts: starfive: jh7110-common: qspi flash setting read-delay 2 cycles max 100MHz

Use qspi flash read-delay and spi-max-frequency settings compatible with
U-Boot bootloader.

Observations from testing on Pine64 Star64 hardware within U-Boot bootloader
and read-delay=2 are spi-max-frequency less than 49.8MHz fails to write,
corrupt data writes at 25MHz to 49.799999MHz, and valid data writes at
49.8MHz to 100MHz (not tested above 100MHz). No valid spi-max-frequency
was found for 1<read-delay<=3 and corrupt data with read-delay=3.

Looking around the Linux codebase it is common to see read-delay 2 cycles
with spi-max-frequency 100MHz and testing confirms this to work in both
U-Boot and Linux.

Signed-off-by: E Shattow <[email protected]>
Reviewed-by: Hal Feng <[email protected]>
Acked-by: Emil Renner Berthing <[email protected]>
Signed-off-by: Conor Dooley <[email protected]>

0 files changed, 0 insertions, 0 deletions