DVD-writer DMA on Intel 915 chipset with 2.6.13.1 kernel

carboncopy · 09-13-2005, 02:54 AM

Hi!

I have the following reading from hdparm. So which hold true? Is DMA on or is it not?

Code:

root@madcow:/etc# hdparm /dev/hdc

/dev/hdc:
 IO_support   =  1 (32-bit)
 unmaskirq    =  0 (off)
 using_dma    =  0 (off)
 keepsettings =  0 (off)
 readonly     =  0 (off)
 readahead    = 256 (on)
 HDIO_GETGEO failed: Invalid argument
root@xpert:/etc# hdparm -I /dev/hdc

/dev/hdc:

ATAPI CD-ROM, with removable media
        Model Number:       _NEC DVD+/-RW ND-6650A
        Serial Number:
        Firmware Revision:  102C
Standards:
        Likely used CD-ROM ATAPI-1
Configuration:
        DRQ response: 3ms.
        Packet size: 12 bytes
Capabilities:
        LBA, IORDY(cannot be disabled)
        DMA: mdma0 mdma1 mdma2 udma0 udma1 *udma2
             Cycle time: min=120ns recommended=120ns
        PIO: pio0 pio1 pio2 pio3 pio4
             Cycle time: no flow control=120ns  IORDY flow control=120ns
root@madcow:/etc#

As noted this drive is on a laptop with Intel 915 chipset powered by 2.6.13.1 kernel.

carboncopy · 09-13-2005, 03:15 AM

hdparm -t /dev/hdc

Timing buffered disk reads 4MB in 3.04 seconds = 1.32MB/sec

!!!
hdparm -d1 /dev/hdc doesn't work.

Snowbat · 09-14-2005, 01:17 AM

Have you tried the X switch?
hdparm -d1 -X udma2 /dev/hdc