Hi, Since you are using libata ata_piix driver and not IDE piix one Jeff and/or Alan are the right people to ask this question... Anyway... On Thursday 31 May 2007, Daniel J Blueman wrote: > I have a SanDisk Extreme IV 4GB CF card, capable of 40MB/s read, but > am seeing 30MB/s read [1], connected directly to the IDE bus on my > ICH8 controller. > > How can I find out if this would be a timing or configuration issue? > On 2.6.20.5 [2], the 120nS timing looks to be right [3], but perhaps multi-word DMA cycle timing seems to be configured OK Shouldn't really matter since it is for multi-word DMA transfers and this device is using UDMA transfers. > no multi-word transfer is hurting here...alas, it can't be enabled > with the libata subsystem and 'hdparm -m', so what else? -m is for multi sector PIO transfers and probably won't help here Everything (except harmless "abnormal status" garbage) seems fine. Where does the max 40MB/s come from? Were you able to get this device to work with this speed using some other controller and/or other OS-es? Thanks, Bart > Daniel > > --- [1] > > # hdparm -t /dev/sdb > /dev/sdb: > Timing buffered disk reads: 94 MB in 3.05 seconds = 30.79 MB/sec > > --- [2] > > ata7: PATA max UDMA/100 cmd 0x000000000001bc00 ctl 0x000000000001b882 > bmdma 0x000000000001b400 irq 17 > ata7.00: CFA: SanDisk SDCFX-4096, HDX 4.04, max UDMA/66 > ata7.00: 8027712 sectors, multi 0: LBA > ata7.00: configured for UDMA/66 > ATA: abnormal status 0x7F on port 0x000000000001b807 > scsi 6:0:0:0: Direct-Access ATA SanDisk SDCFX-40 HDX PQ: 0 ANSI: 5 > SCSI device sdb: 8027712 512-byte hdwr sectors (4110 MB) > sdb: Write Protect is off > sdb: Mode Sense: 00 3a 00 00 > SCSI device sdb: write cache: disabled, read cache: enabled, doesn't > support DPO or FUA > SCSI device sdb: 8027712 512-byte hdwr sectors (4110 MB) > sdb: sdb1 > sd 6:0:0:0: Attached scsi removable disk sdb > > --- [3] > > # hdparm -I /dev/sdb > > /dev/sdb: > > CompactFlash ATA device, with removable media > Model Number: SanDisk SDCFX-4096 > Serial Number: 116802D2807J3335 > Firmware Revision: HDX 4.04 > Standards: > Supported: 4 > Likely used: 4 > Configuration: > Logical max current > cylinders 7964 7964 > heads 16 16 > sectors/track 63 63 > -- > CHS current addressable sectors: 8027712 > LBA user addressable sectors: 8027712 > device size with M = 1024*1024: 3919 MBytes > device size with M = 1000*1000: 4110 MBytes (4 GB) > Capabilities: > LBA, IORDY(may be)(cannot be disabled) > Standby timer values: spec'd by Vendor > R/W multiple sector transfer: Max = 4 Current = 0 > DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 *udma4 > Cycle time: min=120ns recommended=120ns > PIO: pio0 pio1 pio2 pio3 pio4 > Cycle time: no flow control=120ns IORDY flow control=120ns > Commands/features: > Enabled Supported: > Write cache > * CFA feature set > -- > Daniel J Blueman - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
