On Monday, January 04, 2016 at 04:02:26 AM, Phil Sutter wrote: > Hi, > > On Mon, Jan 04, 2016 at 12:47:37AM +0100, Marek Vasut wrote: > > On Monday, January 04, 2016 at 12:38:07 AM, Phil Sutter wrote: > > > The bit which really was missing is the USB mode setting I smuggled in > > > along with my patch - setting the devices to host mode is sufficient > > > for Linux to successfully enumerate the HCD. > > > > OK, so the controller is OTG capable and upon reset, it's in Gadget mode? > > Yes, seems it's capable. Upon reset, register 0x501a0 contains value 0. > Trying to print register 0x511a0 freezes U-Boot for me.
0x501a0 and 0x511a0 are two different registers. Freeze usually indicates disabled clock to the IP block or somesuch. > > > Checking the logs of the vendor's U-Boot fork, it appears that devices > > > 1 and 2 are configured to host mode, while the third is set to device > > > mode. I changed my code to copy that, but am not sure it's necessary > > > at all: The DS414 exports only a single port of the SoC's EHCI, and > > > Linux > > > > > > detects that: > > > | orion-ehci f1050000.usb: EHCI Host Controller > > > | orion-ehci f1050000.usb: new USB bus registered, assigned bus number > > > | 3 orion-ehci f1050000.usb: irq 27, io mem 0xf1050000 > > > | orion-ehci f1050000.usb: USB 2.0 started, EHCI 1.00 > > > | hub 3-0:1.0: USB hub found > > > | hub 3-0:1.0: 1 port detected > > > > > > OTOH I'm not sure how far this configuration is device specific in the > > > first place. What puzzles me is that I couldn't find a reference to > > > this USB mode register at 0x501A8 in Marvell's MV78230 specs, still it > > > seems to be crucial. Does anyone of you have this register referenced > > > in some Marvell datasheet somewhere? > > > > It's the USBMODE register, see for example [1] . It's part of EHCI cores > > which are OTG capable. > > > > [1] http://lxr.free-electrons.com/source/drivers/usb/host/ehci-hcd.c#L179 > > Interesting. I would have expected this to show up in MV78230 specs, but > maybe I missed the part where it clarifies these offsets to be standard > conformant. It seems to be standard comformant, but I didn't see the datasheet. > > > Maybe there's also a more generic way to do this, 'usb start' (which > > > solves the problem without any changes to the SoC init code) seems to > > > not address this register. > > > > Probably add a fixup into ehci-orion.c in Linux or something along those > > lines. It should configure the code according to the "dr_mode" DT prop. > > Hmm. Searching through the relevant DT files didn't yield a result for > "dr_mode". Seems like this property is missing, maybe that's why Linux > fails here? More likely it's not implemented for the MVEBU yet. > Is this something generally user-configurable? (Note that I > don't have the slightest idea of how device mode USB works in Linux). Yes, you can run the core in either Host/Gadget/OTG mode. For that to work, you need to configure the core mode. Best regards, Marek Vasut _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot