CFI problems with 32bit bus and 4 devices

David Woodhouse dwmw2 at
Wed Jan 10 18:06:39 EST 2001

On Wed, 10 Jan 2001, [iso-8859-1] Stéphane Laroche wrote:

> The only difference between the 2 modes are the CFI addresses (you have to
> multiply them by 2 in x8 mode).  So you cannot cover that in the map driver,
> which doesn't know the difference between a CFI and a normal operation.

"BYTE ENABLE: BYTE# low places the device in x8 mode. All data is then
input or output on DQ0-DQ7, while DQ8-DQ15 float. Address A0 selects
between the high and low byte. BYTE# high places the device in x16 mode,
and turns off the A0 input buffer. Address A1 then becomes the lowest
order address."

Yep, I was wrong. It couldn't work the way I was thinking of - you'd have
too few address lines to access the whole chip in x8 mode.

We do need to handle it in the CFI code, as we did before I broke it.


To unsubscribe, send "unsubscribe mtd" to majordomo at

More information about the linux-mtd mailing list