Re: Boot off CF card hangs at "Trying to mount root"

On 29/08/2005, at 19:28, Stefan Bethke wrote:

> Am 28.08.2005 um 18:46 schrieb Stefan Bethke:
>
>
>> Compiling boot, loader, and kernel without a CPUTYPE setting fixed  
>> the boot and loader issues; however, the kernel doesn't seem to be  
>> happy with the CF card:
>>
>> ad3: 489MB <LEXAR ATA FLASH 1.01> at ata1-slave PIO4
>> Trying to mount root from ufs:/dev/ad3s1a
>>
>> Again, I can break into the debugger, but I'm not certain what I  
>> should be looking at.
>>
>
> OK brought home a couple of useful things; I can now run both the  
> HD and the CF card at the same time, and I have a serial console.
>
> Booting into 5-stable from the HD let's me access the CF card just  
> fine. I've attached a verbose boot from both 5-stable and 6-beta3.
>
> The most striking difference (to me) is that 5-stable thinks DMA66  
> is fine (and my tests show that at least reading is not a problem  
> at all), while 6-beta wants to do PIO4, but seemingly gets stuck.

Uhm, both use PIO4 as far as I can tell..

> Time to add debugging to ata?

Enable debugging in ata-all.h and set ATA_R_DEBUG in request->flags  
early in ata_queue_request() and see how far it gets.

I'd suspect subtle timing in the lowest levels though....

- Søren