Observed low throughputs with sdio-wifi interface

Hi All,

      We are using the "friendly arm-S3C2440" board for porting the SDIO
interfaced wifi driver, Here we are able to functioning the through SDIO
wifi interface, But here we have observed very low throughputs when running
the "iperf" TCP and UDP test cases. TCP around 10Mbps and UDP around
12Mbps.

 On atmel and imx platform we have observed higher through puts.
TCP around 25Mbps and UDP around 30Mbps.

But on "friendly arm-S3C2440" only we have observed lower through-puts.
Here SDIO clock has set as 50MHZ in source code, but it operating at 20Mhz.
How can i increase SDIO clock operation frequency to 50Mhz.

Is there any limitations on SDIO clock frequency on S3C2440?
Is there any limitations for through puts wireless operations?


Thanks & Regards
Ch.Siva

It would be very helpfull for us if any body tell us what may be the
problem for getting the lower throughputs on friendly arm board.

Does page 19-4 in the datasheet help?

The way I read it you only have two choices for SDIO clock, "SD" or "MMC"
and the max clock is calculated using the formulae at the bottom of this
page.

Good Luck!