Libertas with if_cs.c on ARM processor

[Ryan Mallon]

Cyril HAENEL wrote:
> Hi all,
> 
> I am not sure I am on the right place, but I don't know where to ask my 
> question.
> 
> I built a custom board based on the AT91SAM9260 ARM processor. My wifi 
> card is based on the marvell 8385 chip, and is connected to the 
> processor with compact flash bus.
> The card is detected but the board freeze when I try to load the helper 
> in the card. The problem comes from the /WAIT signal, after some 
> read/write on the bus the 8385 put this signal low for ever, and the 
> processor wait for ever....
> 
> I looked in detail on the scope, and I seen that the 8385 put the /wait 
> signal low when its chip selects CE1 and CE2 are not active !!
> So I seen it puts the /wait signal low when /IORD and /IOWR are low. 
> Because /IORD and /IOWR are multiplexed with other signal on the 
> AT91SAM9260, it is possible these signals goes low simultaneously. It's 
> seems the 8385 is affected by this situation, even if it is not 
> chip-selected.
> 
> Is someone have a 8385 cf module working on a AT91SAM926x board ? If 
> yes, how have you connected these signals ?

Hi,

First off, I'm a software engineer, so forgive me if my explanation is a
little off :-). We have the Marvell 8385 compact flash (Winstron Wifi
module) working on an AT91SAM9260 based board. Our memory bus is 1.8v so
there are buffers for the conversion from 3v3 on the compact flash
signals and also pullups on the pc_wait_n, pc_rst, pc_reg and pc_rdy
signals to 3v3.

Also, check that your kernel is putting all of the pins in their correct
alternative function mode for compact flash.

~Ryan

-- 
Bluewater Systems Ltd - ARM Technology Solution Centre

       Ryan Mallon                              Unit 5, Amuri Park
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