FWTS Serial Port Console Redirection Table test failing with Modern System IRQ

[ivanhu]

Hi Parasuraman,

FWTS just follow the SPCR specification definition.
https://learn.microsoft.com/en-us/windows-hardware/drivers/serports/serial-port-console-redirection-table

IRQ	1	53	The PC-AT-compatible IRQ used by the UART:
2-7, 9-12, 14-15 = Valid IRQs respectively
0-1, 8, 13, 16-255 = Reserved


I think you might send a change request to SPCR specification, if you think 16 should not be reserved.

Cheers,
Ivan

On 2024/12/4 16:52, Parasuraman, KarthikeyanX wrote:
> Hi,
> 
> Greetings.
> 
> I am checking  the error from one of the tests , *spcr*
> 
> spcr: SPCR Serial Port Console Redirection Table test.
> 
> --------------------------------------------------------------------------------
> 
> Test 1 of 3: SPCR Serial Port Console Redirection Table test.
> 
> Serial Interface: 16550 compatible
> 
> *FAILED [HIGH] SPCRIllegalIRQ: Test 1, SPCR PC-AT compatible **IRQ 0x10** is invalid*
> 
> Baud Rate:        115200
> 
> Terminal Type:    VT100+
> 
> We have checked the code logic from FWTS tool as shown below :
> 
>      /* Check PC-AT compatible UART IRQs */
> 
>      if (spcr->interrupt_type & 1) {
> 
>         switch (spcr->irq) {
> 
>             case 2 ...  7:
> 
>             case 9 ... 12:
> 
>             case 14 ... 15:
> 
>                    break;
> 
>             default:
> 
>              passed = false;
> 
>              fwts_failed(fw, LOG_LEVEL_HIGH,
> 
>                  "SPCRIllegalIRQ",
> 
>                  "SPCR PC-AT compatible IRQ 0x%" PRIx8 " is invalid", spcr->irq);
> 
>              break;
> 
>          }
> 
>      }
> 
> In our Code, we are updating irq value as per our requirement,
> 
> mSpcrTable->Irq = 16;
> 
> We can understand that tool code expects only legacy interrupts *PC-AT IRQs* like (0x00-0x0F) and 0-1, 8, 13, 16-255 are reserved IRQs.
> 
> Could you please clarify why fwts is specifically checking for legacy interrupts and flagging IRQ 16 as an issue?
> Since Our platform & Modern System follows an Advanced interrupt management system, and IRQ 16 is valid within this context.
> 
> Regards,
> Karthikeyan P
> 
> 
> 
>