# FreeBSD 9 RC3 amd64 Intel D525MW AHCI problems



## JeffS (Dec 28, 2011)

Hello,
I want to report a possible bug with FreeBSD 9 RC3, but I don't have any specific info. I'd like to get some help collecting more information before I submit a bug report. Basically, on my Intel D525MW, if I enable AHCI, I start to get odd problems. Sometimes FreeBSD won't mount the filesystems read-only, sometimes it will fail to start sshd (with or without a Segmentation Fault), sometimes it will refuse to log me in, or sometimes it will log me in, display the MOTD and log me off.

Disabling AHCI in the BIOS seems to fix the problems. I updated the BIOS to the latest version, which didn't seem to fix the problem.

I suppose that the problem might in fact be my Compact Flash -> SATA converter, which is this one.

Thanks,
Jeff


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## mav@ (Dec 28, 2011)

CF->SATA converter is in fact a PATA->SATA converter. I would recommend to check what PATA transfer modes your card and converter support and what are negotiated. I never hit this, but code in ata(4) driver tells that there could be limitations that are not properly reported by devices. Unluckily the new ahci(4) driver doesn't have a way to limit PATA mode during boot. If you manage to boot somehow, you may try to do:
`camcontrol negotiate ada0 -M WDMA2`
`camcontrol rescan X`
where X is a CAM bus number of the device from the *camcontrol devlist -v* output. If it helps, I can add mode setting tunables support to ahci(4), but you will have to build a custom kernel to add it.


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## JeffS (Dec 29, 2011)

Hello mav, thanks for your reply.

I am able to get into single user mode with AHCI enabled.

[cmd=]camcontrol devlist -v[/cmd] gives


```
scbus0 on ahcich0 bus0:
<CF 8B 20101001> at scbus0 taret 0 lun 0 (ada0,pass0)
...
```

[cmd=]camcontrol negotiate ada0 -M WDMA2[/cmd] gives


```
Current Parameters:
(pass0:ahcich0:0:0:0): SATA revision: 2.x
(pass0:ahcich0:0:0:0): ATA mode: UDMA6
(pass0:ahcich0:0:0:0): ATAPI packet length: 0
(pass0:ahcich0:0:0:0): PIO tranasaction length: 512
(pass0:ahcich0:0:0:0): PMP presence: 0
(pass0:ahcich0:0:0:0): Number of tags: 32
(pass0:ahcich0:0:0:0): SATA capabilities: 00000030
camcontrol: You can modify only user settings for ATA/SATA
```

[cmd=]camcontrol rescan scbus0[/cmd] gives


```
Re-scan of bus 0 was successful
```

I'm not sure what all this means, but I hope it helps you.

Exiting to multi-user mode results in the same errors after this procedure.

This isn't a big deal to me, since I can just use IDE mode. I might try using a normal hard drive later to see if FreeBSD 9 RC3 has the same problem without the converter.


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## mav@ (Dec 29, 2011)

JeffS said:
			
		

> [cmd=]camcontrol negotiate ada0 -M WDMA2[/cmd] gives
> 
> 
> ```
> ...


I'm sorry, there should be -U option also to modify User, not a Current settings.



			
				JeffS said:
			
		

> This isn't a big deal to me, since I can just use IDE mode. I might try using a normal hard drive later to see if FreeBSD 9 RC3 has the same problem without the converter.


Report if any. I've seen many problems with CF->SATA adapters, so not very surprised with one more. For CF itis not important whether it is AHCI or IDE, but for SATA disks performance difference can be about 30% and more because of NCQ.


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