[U-Boot] Numonyx NOR support in u-boot

[Todd Fischer]

Hi,

We are seeing NOR write failures on 6 of the 10 boards (DM6446 ARM SoC
with Numonyx JS28F256M29EWL NOR flash chip).  Four of the boards seem to
work without error.  All 10 boards were made on the same manufacturing
line at the same time.

Initially, we couldn't properly read the  QRY response from the chip.
We had to use this patch

http://www.mail-archive.com/u-boot@lists.denx.de/msg26614.html

We are getting 'flash not erased' error or timeout error.  We have tried
monitoring D7 (busy) and monitoring D6 (activity toggle) to detect
erase / program command completion / timeout.  We have tried changing
the timing of the control signals to the NOR chip, but need to use a
logic state analyzer to verify the timing is changed as expected.

Example error output:

> cp 0x81700000 0x02000000 0x400000
Copy to Flash... Flash not Erased
Timeout writing to Flash

> cp 0x81700000 0x02000000
0x400000                                       
Copy to Flash... Flash write timeout at address 2000000 data
129f34       

We have tried cp, cp.b, cp.w and get the same results.

With 4 boards working correctly, the code must be close.

Any suggestions (beyond looking at the signals with a Logic State
Analyzer)?

Todd