warum Ausgabe von lscpi bezüglich inkonsistent ist

Question

Below Bar ist meine Ausgabe von lspci -xxxx -vvvv -nn

00:02.0 VGA compatible controller [0300]: InnoTek Systemberatung GmbH VirtualBox Graphics Adapter [80ee:beef] (prog-if 00 [VGA controller]) 
    Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- 
    Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- 
    Latency: 0 
    Interrupt: pin A routed to IRQ 18 
    Region 0: Memory at e0000000 (32-bit, prefetchable) [size=64M] 
    Expansion ROM at <unassigned> [disabled] 
    Kernel driver in use: vboxvideo 
00: ee 80 ef be 07 00 00 00 00 00 00 03 00 00 00 00 
10: 08 00 00 e0 00 00 00 00 00 00 00 00 00 00 00 00 
20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
30: 00 00 00 00 00 00 00 00 00 00 00 00 0b 01 00 00 
40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
50: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
60: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 

Insbesondere über die folgenden Zeilen möchte ich fragen:

Region 0: Memory at e0000000 (32-bit, prefetchable) [size=64M] 

und

10: 08 00 00 e0 00 00 00 00 00 00 00 00 00 00 00 00 

Basierend auf this (look at section 12.1.3) sollte der Wert BAR0seinund nicht e0000000, d.h. das letzte Byte sollte 08 und nicht 00 sein, wie es in der Beschreibung von Region 0 steht. Warum ist es so? Was vermisse ich?

Answer 1

Die niedrigen 4 Bits sind nicht Teil der Adresse. Dieses spezielle Bit (Bit # 3 mit dem Wert 0x08) ist das Bit, das den Bereich als vorabrufbar markiert. Siehe https://en.wikipedia.org/wiki/PCI_configuration_space#Bus_enumeration oder http://wiki.osdev.org/PCI#Base_Address_Registers oder führen Sie einfach eine Internetsuche nach "PCI Configuration Space Header"