El Domingo, 18 de Marzo de 2007, Tejun Heo escribió: > Jose Alberto Reguero wrote: > > I found that the driver work well for Marvel 6121 without the flag > > ATA_FLAG_SKIP_D2H_BSY. > > What is the meaning of this flag? > > This is usually meaningful with hotplug. The problem is that, on some > SATA controllers including ahci and sata_sil24, the wait for the first > D2H Reg FIS indicating device readiness isn't reliable. It's supposed > to work like the following (sata_sil behaves pretty good on this regard). > > 1. User hotplug device to port and PHY event interrupt raised, the > controller should set BSY status bit. > > 2. libata EH kicks in and waits for BSY to clear (current timeout 30s). > Done by the first D2H Reg FIS. Drives usually send this after spinup > is complete. > > 3. After BSY is cleared, the device is reset. > > The problem with ahci and sata_sil24 is that there really is no TF > status register is non-existent or emulated in some way and they doesn't > let us reliably wait for !BSY after hotplug event. This often makes the > wait in #2 timeout and that's 30 seconds. :-( > > So, the flag makes libata EH skip #2. Post-reset waiting is reliable, > so there is no timeout. But this causes problems on some devices (the > Quantum GoVault thing) which takes a looooong time to get ready and > don't respond correctly to phy reset while it's busy initializing. > > The flag is there primarily for ICH ahci's. Marvell might be different. > Care to remove SKIP_D2H_BSY and test a LOT of hotplugging with several > different devices? :-) With SKIP_D2H_BSY I have a old dmesg -> dmesg1 (2.6.20 I think) I test with and a external sata disk without SKIP_D2H_BSY -> dmes2 (2.6.21-rc4) Both takes ~8 seconds. Thanks Jose Alberto
ata4: exception Emask 0x10 SAct 0x0 SErr 0x0 action 0x2 frozen ata4: (irq_stat 0x02400000, PHY RDY changed) ata4: waiting for device to spin up (8 secs) ata4: soft resetting port ata4: softreset failed (port busy but CLO unavailable) ata4: softreset failed, retrying in 5 secs ata4: hard resetting port ata4: SATA link up 1.5 Gbps (SStatus 113 SControl 300) ata4.00: ATA-7, max UDMA/133, 586072368 sectors: LBA48 NCQ (depth 31/32) ata4.00: Drive reports diagnostics failure. This may indicate a drive ata4.00: fault or invalid emulation. Contact drive vendor for information. ata4.00: configured for UDMA/133 ata4: EH complete scsi 3:0:0:0: Direct-Access ATA ST3300831AS 3.03 PQ: 0 ANSI: 5 SCSI device sdd: 586072368 512-byte hdwr sectors (300069 MB) sdd: Write Protect is off sdd: Mode Sense: 00 3a 00 00 SCSI device sdd: write cache: enabled, read cache: enabled, doesn't support DPO or FUA SCSI device sdd: 586072368 512-byte hdwr sectors (300069 MB) sdd: Write Protect is off sdd: Mode Sense: 00 3a 00 00 SCSI device sdd: write cache: enabled, read cache: enabled, doesn't support DPO or FUA sdd: sdd1 sd 3:0:0:0: Attached scsi disk sdd sd 3:0:0:0: Attached scsi generic sg3 type 0
ata4: exception Emask 0x10 SAct 0x0 SErr 0x0 action 0x2 frozen ata4: (irq_stat 0x02400000, PHY RDY changed) ata4: port is slow to respond, please be patient (Status 0x80) ata4: soft resetting port ata4: SATA link up 1.5 Gbps (SStatus 113 SControl 300) ata4.00: ATA-7: ST3300831AS, 3.03, max UDMA/133 ata4.00: 586072368 sectors, multi 0: LBA48 NCQ (depth 31/32) ata4.00: configured for UDMA/133 ata4: EH complete scsi 3:0:0:0: Direct-Access ATA ST3300831AS 3.03 PQ: 0 ANSI: 5 SCSI device sdd: 586072368 512-byte hdwr sectors (300069 MB) sdd: Write Protect is off sdd: Mode Sense: 00 3a 00 00 SCSI device sdd: write cache: enabled, read cache: enabled, doesn't support DPO or FUA SCSI device sdd: 586072368 512-byte hdwr sectors (300069 MB) sdd: Write Protect is off sdd: Mode Sense: 00 3a 00 00 SCSI device sdd: write cache: enabled, read cache: enabled, doesn't support DPO or FUA sdd:<6>ata4: D2H reg with I during NCQ, this message won't be printed again sdd1 sd 3:0:0:0: Attached scsi disk sdd sd 3:0:0:0: Attached scsi generic sg5 type 0
