Hi Aaron, On Sat, Sep 7, 2019 at 11:08 AM Aaron Williams <awilli...@marvell.com> wrote: > > Hi, > > I am seeing crashes in our XHCI implementation based on a Designware USB 3.1 > core. One thing I noticed is that this core sets the PAE bit in the HCCparams. > The result of this is that when there is a short packet and there are two TDs, > then when PAE is set there will be two responses with the second one being > success. I'm still not sure if the length field I'm seeing is correct or not, > but it appears that neither Linux nor U-Boot can handle HCs with the PAE bit > set. See the eXtendable Host Controller Interface 1.1 sections 4.10.1.1 and > 5.3.6. >
It looks this PAE bit was introduced in spec 1.1. U-Boot xHCI driver was ported from an earlier version of Linux xHCI driver, and I doubt it could correctly handle it. But you mentioned that Linux could not handle HCs with PAE set. Did you try the latest kernel? > With short packets with the PAE bit set with to TRBs I get two responses when > the data fits in the first TRB. The first event TRB contains a short packet > response with the length set to the amount of space within the first TRB that > is actually used. The second TRB event is a success completion code, as is > described in section 4.10.1.1.1. > > Personally I find this PAE bit a major pain in the arse that causes more > trouble than it's worth. > Regards, Bin _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot