[Qemu-devel] CDROM: why can it not be changed to PIO mode?

[Zhi Yong Wu]

HI, guys,

I managed to change one cdrom on guest from DMA mode to PIO mode, but
failed. Did anyone also met this same issue before? If you have some
experience to solve this, Can you share with me?

/dev/cdrom:

 Model=QEMU, FwRev=0.15.90, SerialNo=QM00003
 Config={ Fixed Removeable DTR<=5Mbs DTR>10Mbs nonMagnetic }
 RawCHS=0/0/0, TrkSize=0, SectSize=0, ECCbytes=4
 BuffType=DualPortCache, BuffSize=256kB, MaxMultSect=0
 CurCHS=0/0/0, CurSects=0, LBA=yes, LBAsects=0
 IORDY=no, tPIO={min:300,w/IORDY:180}, tDMA={min:180,rec:180}
 PIO modes:  pio0 pio3 pio4
 DMA modes:  sdma0 sdma1 sdma2 mdma0 mdma1 *mdma2
 UDMA modes: udma0 udma1 udma2 udma3 udma4 udma5
 AdvancedPM=no
 Drive conforms to: Unspecified:  ATA/ATAPI-1,2,3,4

 * signifies the current active mode

The log when its mode is changed:

/dev/cdrom:
 setting xfermode to 8 (PIO flow control mode0)
 HDIO_DRIVE_CMD(setxfermode) failed: Invalid exchange


-- 
Regards,

Zhi Yong Wu