Messages in this thread | | | From | Jos Hulzink <> | Subject | Re: [RFC] How to fix MPS 1.4 + ACPI behaviour ? | Date | Tue, 13 May 2003 10:54:25 +0200 |
| |
Hi,
As you can see below, current ACPI implementation concludes it has to use the PIC, before it finds the PRT. No occurences of PRT in dmesg before this one.
vvvv ACPI: Using PIC for interrupt routing ^^^^ ACPI: PCI Interrupt Link [LNKA] (IRQs 3 4 *5 6 7 9 10 11 12 14 15) ACPI: PCI Interrupt Link [LNKB] (IRQs 3 4 5 6 *7 9 10 11 12 14 15) ACPI: PCI Interrupt Link [LNKC] (IRQs 3 4 5 6 7 9 *10 11 12 14 15) ACPI: PCI Interrupt Link [LNKD] (IRQs 3 4 5 6 7 9 10 *11 12 14 15) ACPI: PCI Root Bridge [PCI0] (00:00) PCI: Probing PCI hardware (bus 00) vvvv ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT] ^^^^
Jos
On Monday 12 May 2003 23:29, STK wrote: > For me the linux kernel should invoke the _PIC method with the right > parameter. > > Look at the specification Section > > << ================ Start ================ > 5.8.1 _PIC Method > The \_PIC optional method is to report to the BIOS the current interrupt > model used by the OS. This > control method returns nothing. The argument passed into the method > signifies the interrupt model OSPM > has chosen, PIC mode, APIC mode, or SAPIC mode. Notice that calling this > method is optional for OSPM. > If the method is never called, the BIOS must assume PIC mode. It is > important that the BIOS save the value > passed in by OSPM for later use during wake operations. > _PIC(x): > _PIC(0) => PIC Mode > _PIC(1) => APIC Mode > _PIC(2) => SAPIC Mode > _PIC(3-n) => Reserved > > ==================== End ====================> > > ==> No MADT table, so ACPI sets up the APIC in PIC mode (which I wonder > wether correct, but ok) > For me the kernel should invoke the _PIC method with the right > parameter, in this case the ACPI module will receive the right table > during the _PRT > > Bios ASL code: > Method(_PRT) > { > If(\PICF) <== internal variable set by _PIC > { > ==> Returning APIC Mode > Return(APIC) > } > Else > { > ==> Returning PIC Mode > Return(PICM) > } > } > > Regards, > > Yann > > > -----Original Message----- > From: Jos Hulzink [mailto:josh@stack.nl] > Sent: lundi 12 mai 2003 22:51 > To: STK; 'linux-kernel' > Cc: 'Zwane Mwaikambo' > Subject: Re: [RFC] How to fix MPS 1.4 + ACPI behaviour ? > > On Monday 12 May 2003 22:40, STK wrote: > > Hi, > > > > If no Multiple APIC Description Table (MADT) is described, in this > > case the _PIC method can be used to tell the bios to return the right > > table (PIC or APIC routing table). > > > > In this case, if the MPS table describes matches the ACPI APIC table > > (this is the case, because the ACPI APIC table is built from the MPS > > table), you do not need to remap all IRQs. > > So, it's more or less a bug in the ACPI code that should do some things > when > no MADT is dectected ? Or do I understand you wrong ? > > Jos
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |