[LinuxBIOS] uart_init hangs?

Corey Osgood corey_osgood at verizon.net
Tue Mar 27 02:37:48 CEST 2007


Uwe Hermann wrote:
> On Mon, Mar 26, 2007 at 02:10:20AM -0400, Corey Osgood wrote:
>> Alright, I know I ask too many questions, but what would cause uart_init
>> to hang? I'm trying to get serial output on ite it8705f, and my POST
>> card tells me that it's hanging during uart_init. I've made a bunch of
>> changes to it8705f_early_serial.c, mainly to set up serial port 1
>> manually, but nothing seems to help. Also, there's one small error in
>> the last line of that file, according to the datasheet:
>>
>>     it8705f_sio_write(0x00, IT8705F_CONFIG_REG_CC, 0x02); //need to
>> change 0x02 to 0x01
> 
> This line is correct, I think. The datasheet says
> 
>   Set bit 1 of the Configure Control Register (Index: 02h) to "1" to exit
>   the MB PnP mode.
> 
> IT8705F_CONFIG_REG_CC is 0x02, and the 0x02 in the line above is correct
> because it sets bit 1 (not bit 0).
> 
> 
> I _think_ I got serial output with that Super I/O at some point, but I
> can't remember exactly, so maybe there's still something todo...
> 
> 
> Uwe.
> 

I've attached my it8705f_early_serial.c and auto.c. And yes, Uwe, you
were right, it was correct. I even put in a comment about it and still
read it wrong. But, I'm still not getting serial output, even with that
fixed. I've put in a few outb()s, and that tells me it's finishing with
the early serial, but not leaving uart_init(). I'm wondering if the
vt8235 is somehow interfering with the serial output. Suggestions?

Thanks,
Corey
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