Re: AT91 IDE module

["Radovan Vápeník" <radovan.vapenik@tcz.cz>]

Stanislaw Gruszka napsal(a):
> On Thu, Nov 25, 2010 at 09:53:19PM +0100, Radovan Vapeník wrote:
>   
>>> We do not detect any IDE device, registers do not contain status/data
>>> that IDE layer expect. As far only two possible reasons of that
>>> problem come in mind:
>>> - board specific code does not reset CF device (with proper
>>>  reset duration?). This is expected, there is rst_pin in
>>>  struct at91_cf_data but driver does not use it
>>> - CF 9 pin (ATA SEL) is not grounded or set to 0 if connected
>>>  to controller (also in board specific initialization code)
>>>
>>> To debug problem further, you can add your own code at the end of
>>> at91_ide_probe(), which read/write IDE register to see if device
>>> react properly and give some sensible status values.
>>>
>>> Stanislaw
>>>
>>>       
>> Seems problem is really on reset pin, i have analysed using
>> oscilloscope and on reset pin is still in logical "1", without
>> change during module loading. I will try to find out why is this
>> happening.
>>     
>
> I was unclear. Driver does not change reset pin. Reset need to be
> done in board initialization code. You have to add something like that
>
> #define RST_PIN AT91_PIN_PC5
> at91_set_gpio_output(RST_PIN, 1);
> at91_set_gpio_value(RST_PIN,0);
> mdelay(2);
> at91_set_gpio_value(RST_PIN,1);
>
> in your arch/arm/mach-at91/board-NAME.c (I'm not sure if 2ms is
> correct IDE reset duration).
>
> Stanislaw
>
>   

On the data bus is something strange - I have scanned data bus using 
oscilloscope at the moment, when processor send CS signal to 
CompactFlash. The  screenshot from oscilloscope is here - 
http://www.vapenik.com/files/cf_init.png. The yellow color is CFCS0, 
blue is one data pin on the data bus. The red arrow shows the possible 
problem - there is transient. And in 4. quadrant is some transient too, 
question is why it happens (but pc is working correctly, i boot linux 
without problem). This is on EBI0, there is connected NAND Flash + 2x 
SDRAM and Compact Flash. When I measured EBI0, the strange  timing with 
transient is only on low 16 bits of EBI0 
(http://www.vapenik.com/files/data-0-15.png , one random wire on data 
bus EBI0, low 16bits), high 16 bits are ok 
(http://www.vapenik.com/files/data-16-31.png , one random wire on EBI0, 
high 16 bits). But almost this same happens on Evaluation Board from 
Atmel, so I really don't know where is problem.

Radovan