• Naga Chumbalkar's avatar
    x86, ioapic: Print IRTE when IR is enabled · 3040db92
    Naga Chumbalkar authored
    When "apic=debug" is used as a boot parameter, Linux prints the IOAPIC routing
    entries in "dmesg". Below is output from IOAPIC whose apic_id is 8:
    
    # dmesg | grep "routing entry"
    IOAPIC[8]: Set routing entry (8-1 -> 0x31 -> IRQ 1 Mode:0 Active:0 Dest:0)
    IOAPIC[8]: Set routing entry (8-2 -> 0x30 -> IRQ 0 Mode:0 Active:0 Dest:0)
    IOAPIC[8]: Set routing entry (8-3 -> 0x33 -> IRQ 3 Mode:0 Active:0 Dest:0)
    ...
    
    Similarly, when IR (interrupt remapping) is enabled, and the IRTE
    (interrupt remapping table entry) is set up we should display it.
    
    After the fix:
    
    # dmesg | grep IRTE
    IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:31 Dest:00000000 SID:00F1 SQ:0 SVT:1)
    IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:30 Dest:00000000 SID:00F1 SQ:0 SVT:1)
    IOAPIC[8]: Set IRTE entry (P:1 FPD:0 Dst_Mode:0 Redir_hint:1 Trig_Mode:0 Dlvry_Mode:0 Avail:0 Vector:33 Dest:00000000 SID:00F1 SQ:0 SVT:1)
    ...
    
    The IRTE is defined in Sec 9.5 of the Intel VT-d Specification.
    Signed-off-by: default avatarNaga Chumbalkar <nagananda.chumbalkar@hp.com>
    Link: http://lkml.kernel.org/r/20110712211704.2939.71291.sendpatchset@nchumbalkar.americas.cpqcorp.netSigned-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
    3040db92
io_apic.c 97.3 KB