Crucial X9 USB SSD very slow on Haiku, xHCI max_burst_payload error

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21

Hum, even in Bulk-Only, it should be able to do more than 30MB/s when connected on an USB 3 port.

Maybe first thing is to check if the port is working at USB 3 speed under Haiku. I guess our USB stack reports that in syslog, right?

22

Not sure if upstream picked up my USB3 hub fix yet, but otherwise, if it is behind a hub it will recognize those devices as USB2 devices. So make sure the port you are using is on the root controller and not behind a hub.

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23

Damn, you’re right, I forgot about this issue!

I’ll open a Trac ticket for it, and push a CR based on your fix suggestion.

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24

Please be sure to check against the spec, these patches are incomplete most of the time.

25

There is already a ticket about it: Making sure you're not a bot!

But my understanding is that UAS is a completely different protocol, with different USB interface protocol definition.

My understanding at the time was that device would implement either UAS or CBI, but not both at the same time. So an UAS device would not work at all on a system that only has drivers for CBI mass storage.

It’s possible to implement both, but I haven’t yet seen UAS mentionned in lsusb or listusb output (you would see it as an interface with protocol 0x62). Maybe it’s just because I own only old hardware and no modern USB3 mass storage devices. It would be nice to see the ouytput of listusb -v for this device to confirm if that’s an option, then.

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For bootability concerns, most UASP able USB devices should support Bulk-Only too. But probably none would support the old and deprecated CBI, which make sense only for old and slow devices, like USB floppy drives.

27

I would also like to see the listusb -v. It doesn’t look like the hub issue I mentioned before. I am deep into everything disk speed related at the moment, and the lack of UAS is not going to produce USB2 speeds. It would be needed to get to the 1Gbps throughput of the X9, but does not explain the speeds mentioned by OP.

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The USB3 hub fixes have been merged along with some other changes, so this should be retested now anyway.

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29

It is my understanding that the usb_disk driver currently doesn’t support UAS devices or implement the UAS protocol. At least this table only mentions support for BBB devices.
static usb_support_descriptor supportedDevices[] = {
{ USB_MASS_STORAGE_DEVICE_CLASS, 0x06 /* SCSI */, 0x50 /* bulk */, 0, 0 },
{ USB_MASS_STORAGE_DEVICE_CLASS, 0x02 /* ATAPI */, 0x50 /* bulk */, 0, 0 },
{ USB_MASS_STORAGE_DEVICE_CLASS, 0x05 /* ATAPI */, 0x50 /* bulk */, 0, 0 },
{ USB_MASS_STORAGE_DEVICE_CLASS, 0x04 /* UFI */, 0x00, 0, 0 }
};
UAS would be subclass 0x08 and protocol 0x62 if I remember correctly. Or is it handled somewhere else?

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It’s currently handled nowhere, as Haiku don’t have yet support for UASP.