But autonegotiating mwdma/pio modes with appropriate slow drives always works fine. Via VT8235 chipset. Kernel 2.6.25-rc4-and-a-bit from saturday's git. Tested on a Western Digital UDMA/100 disk via a nice 80-pin cable and had the same behaviour when I swapped in a pata-compactflash adapter. Forcing UDMA1 with libata.force=1.00:udma1 works fine - speed is fine, hdparm -I looks fine. Forcing MWDMA2 with libata.force=1.00:mwdma2 hangs hard when scanning partitions. Forcing PIO3 with libata.force=1.00:pio3 results in PIO0 speeds and hdparm -I reporting that best udma mode is still selected. (ignore the unknown partition table - the disk is wiped and unpartitioned) MWDMA hang log: [ 5.026117] ACPI: PCI Interrupt 0000:00:11.1[A] -> Link [LNKA] -> GSI 15 (level, low) -> IRQ 15 [ 5.026412] pata_via 0000:00:11.1: VIA VLink IRQ fixup, from 255 to 15 [ 5.026998] scsi0 : pata_via [ 5.027548] scsi1 : pata_via [ 5.038879] ata1: PATA max UDMA/133 cmd 0x1f0 ctl 0x3f6 bmdma 0xe000 irq 14 [ 5.038978] ata2: PATA max UDMA/133 cmd 0x170 ctl 0x376 bmdma 0xe008 irq 15 [ 5.194536] ata1.00: ATA-5: WDC WD200EB-00CSF0, 04.01B04, max UDMA/100 [ 5.194536] ata1.00: 39102336 sectors, multi 16: LBA [ 5.194536] ata1.00: FORCE: xfer_mask set to mwdma2 [ 5.201625] ata1.00: configured for MWDMA2 [ 5.201625] scsi 0:0:0:0: Direct-Access ATA WDC WD200EB-00CS 04.0 PQ: 0 ANSI: 5 [ 5.202300] sd 0:0:0:0: [sda] 39102336 512-byte hardware sectors (20020 MB) [ 5.202432] sd 0:0:0:0: [sda] Write Protect is off [ 5.202597] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [ 5.202872] sd 0:0:0:0: [sda] 39102336 512-byte hardware sectors (20020 MB) [ 5.202991] sd 0:0:0:0: [sda] Write Protect is off [ 5.203153] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [ 5.203254] sda: The system is at this point completely wedged, not responding to magic sysrq or anything. PIO forcing log: [ 5.024147] ACPI: PCI Interrupt 0000:00:11.1[A] -> Link [LNKA] -> GSI 15 (level, low) -> IRQ 15 [ 5.024485] pata_via 0000:00:11.1: VIA VLink IRQ fixup, from 255 to 15 [ 5.025080] scsi0 : pata_via [ 5.025587] scsi1 : pata_via [ 5.036920] ata1: PATA max UDMA/133 cmd 0x1f0 ctl 0x3f6 bmdma 0xe000 irq 14 [ 5.037017] ata2: PATA max UDMA/133 cmd 0x170 ctl 0x376 bmdma 0xe008 irq 15 [ 5.193551] ata1.00: ATA-5: WDC WD200EB-00CSF0, 04.01B04, max UDMA/100 [ 5.193551] ata1.00: 39102336 sectors, multi 16: LBA [ 5.193551] ata1.00: FORCE: xfer_mask set to pio3 [ 5.200655] ata1.00: configured for PIO3 [ 5.200655] scsi 0:0:0:0: Direct-Access ATA WDC WD200EB-00CS 04.0 PQ: 0 ANSI: 5 [ 5.201347] sd 0:0:0:0: [sda] 39102336 512-byte hardware sectors (20020 MB) [ 5.201493] sd 0:0:0:0: [sda] Write Protect is off [ 5.201690] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [ 5.202013] sd 0:0:0:0: [sda] 39102336 512-byte hardware sectors (20020 MB) [ 5.202130] sd 0:0:0:0: [sda] Write Protect is off [ 5.202291] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [ 5.202392] sda: unknown partition table [ 5.227680] sd 0:0:0:0: [sda] Attached SCSI disk [ 5.227680] sd 0:0:0:0: Attached scsi generic sg0 type 0 hdparm -tT /dev/sda /dev/sda: Timing cached reads: 94 MB in 2.03 seconds = 46.31 MB/sec Timing buffered disk reads: 10 MB in 3.18 seconds = 3.15 MB/sec hdparm -I /dev/sda /dev/sda: ATA device, with non-removable media Model Number: WDC WD200EB-00CSF0 Serial Number: XX-XXXXXXXXXXXX Firmware Revision: 04.01B04 Standards: Supported: 5 4 3 Likely used: 6 Configuration: Logical max current cylinders 16383 16383 heads 16 16 sectors/track 63 63 -- CHS current addressable sectors: 16514064 LBA user addressable sectors: 39102336 device size with M = 1024*1024: 19092 MBytes device size with M = 1000*1000: 20020 MBytes (20 GB) Capabilities: LBA, IORDY(can be disabled) bytes avail on r/w long: 40 Standby timer values: spec'd by Standard, with device specific minimum R/W multiple sector transfer: Max = 16 Current = 16 Recommended acoustic management value: 128, current value: 254 DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 *udma5 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: * SMART feature set Security Mode feature set * Power Management feature set * Write cache * Look-ahead * Host Protected Area feature set * WRITE_BUFFER command * READ_BUFFER command * DOWNLOAD_MICROCODE SET_MAX security extension Automatic Acoustic Management feature set Security: supported not enabled not locked not frozen not expired: security count not supported: enhanced erase HW reset results: CBLID- above Vih Device num = 0 determined by the jumper Checksum: correct -- -erik http://useofwords.blogspot.com/ -- 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
