Hi Venkat,

I've heard several reports about the annoying message.

The reason for it should be the conflict between the MRST
earlyprintk console (earlyprintk=mrst in cmdline) and the
real spi max3110 console aka ttyS0, and actually the 2
consoles use the same hardware.

I developed that early console mainly for MRST/MDF power
on use, which is to debug the early kernel boot by hacky
direct operating the DW SPI0 controller, long before the
spi driver subsystem get inited which I developed for the
MRST power on So when the spi subsystem is up, there is
conflict between them, other spi devices connected to
SPI0 including max3110 itself will access the SPI0 controller
by apis from spi core, while the earlyprintk still directly
access controller, so likely the message will be triggered out.

And in current phase, the earlyprintk should be disabled for
normal stable kernels, and I suggest to remove the
"earlyprintk=mrst" from cmdline for Meego kernel. Another way
is to downgrade the error message to a dev_dbg().

Thanks,
Feng
________________________________________
From: [email protected] 
[mailto:[email protected]] On Behalf Of Jayaraman, Venkat
Sent: Friday, February 18, 2011 3:03 PM
To: [email protected]
Subject: [Meego-kernel] Question on Designware SPI Controller Driver

Hi,
                I consistently see the following message being printed from the 
Designware SPI controller driver (dw_spi.c) during the booting phase on 
Medfield platform.

"Status keeps busy for 5000us after a read/write"

                Seems like a "write" inside the interrupt handler is causing 
this. Any idea why this happens?

Thanks
Venkat 
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