Re: [coreboot] how to route IRQ4 (COM1) on LPC bus for bayleybay_fsp

[benoit]

Hi,

As explained in my post, I am not using the UART located in the Baytrail
SOC.
I used an SIO for serial line connected to the LPC bus.
So to have the IRQs of these serial lines, I obviuosly need to SERIRQ.
The IRQEN is only for the COM1 located in the SOC.

Thanks for your help
Benoit

On 14/01/2016 23:09, Aaron Durbin wrote:
> On Tue, Jan 12, 2016 at 2:32 PM, benoit  wrote:
> > Hi all,
> >
> > I am currently running coreboot + fsp on a E3837 cpu based platform.
> > My platform has serial line in a LPC device.
> > Firstly, I activated the SERIRQ in continous mode.
>
> SERIRQ has nothing to do w/ COM1. SERIRQ is pulled in on LPC.
> > Nevertheless under operating system, the IRQ4 for COM1 is not available.
>
> IRQEN (IRQE)—Offset 88h bit 4 indicates UART IRQ4 Enable. The
> datasheet says RO, but you could double check that it's RW. That sit
> behind the ILB_BASE_ADDRESS.
>
> In the datasheet it's section 34.3.53.
> http://www.intel.com/content/www/us/en/embedded/products/bay-trail/atom-e380...
> > I checked out the file  src/mainboard/intel/bayleybay_fsp/irqtable.h
> > And I saw that for the LPC interface :
> >
> > PCI_DEV_PIRQ_ROUTE(PCU_DEV,     H, G, B, C)
> > ...
> > #define PIRQ_PIC_ROUTES \
> >         PIRQ_PIC(A,  4), \
> >         PIRQ_PIC(B,  5), \
> >         PIRQ_PIC(C,  7), \
> >         PIRQ_PIC(D, 10), \
> >         PIRQ_PIC(E, 11), \
> >         PIRQ_PIC(F, 12), \
> >         PIRQ_PIC(G, 14), \
> >         PIRQ_PIC(H, 15)
> >
> > I know that this configuration is available from the ILB_BASE_ADDRESS
> > (0xfed08000).
> > But I don't really understand, how to route the IRQ4 from LPC dev.
> >
> > Is someone can explain to me how to do it properly?
> >
> > Many thanks in advance
> > Benoit