Re: next take at setting up a dma mask by default for platform devices

2019-08-15 Thread Alan Stern
have a respun version ready, but I'd really like to hear some > comments from usb developers about the approach before spamming > everyone again.. I didn't see any problems with your approach at first glance; it looked like a good idea. Alan Stern _

Re: How to resolve an issue in swiotlb environment?

2019-06-19 Thread Alan Stern
56 bytes? Yes, we can. In fact, the SCSI core doesn't handle devices with block size < 512. > In any case, I am looking into adding SG support vhci-hci at the moment. > > Looks like the following is the repo, I should be working with? > > git://git.infradead.org/users/hch/misc.git It doesn't matter. Your work should end up being independent of Christoph's, so you can base it on any repo. Alan Stern

Re: How to resolve an issue in swiotlb environment?

2019-06-14 Thread Alan Stern
e in plan > to drop virt_boundary_mask stuff? Not yet. But since it doesn't do what we want anyway, this should be fixed quickly. Alan Stern

Re: How to resolve an issue in swiotlb environment?

2019-06-13 Thread Alan Stern
On Thu, 13 Jun 2019, Christoph Hellwig wrote: > On Wed, Jun 12, 2019 at 10:43:11AM -0400, Alan Stern wrote: > > Would it be okay to rely on the assumption that USB block devices never > > have block size < 512? (We could even add code to the driver to > > enforce

Re: How to resolve an issue in swiotlb environment?

2019-06-12 Thread Alan Stern
occasional error.) As I mentioned before, the only HCD that sometimes ends up with maxpacket = 1024 but is unable to do full SG is vhci-hcd, and that one shouldn't be too hard to fix. Alan Stern

Re: How to resolve an issue in swiotlb environment?

2019-06-11 Thread Alan Stern
e2(): us->pusb_dev->bus->sysdev. >From uas_probe(): udev->bus->sysdev. The ->sysdev field points to the device used for DMA mapping. It is often the same as ->controller, but sometimes it is ->controller->parent because of the peculiarities of some platforms. Alan Stern

Re: How to resolve an issue in swiotlb environment?

2019-06-10 Thread Alan Stern
gs of the block layer. If you can suggest a better way to express our requirement, that would be great. Alan Stern PS: There _is_ a flag saying whether an HCD supports SG. But what it means is that the driver can handle an SG list that meets the requirement above; it doesn't mean that the d

Re: usb HC busted?

2018-07-20 Thread Alan Stern
t controllers? As far as I know, the other host controller drivers don't really care how this is done. xHCI is the only technology where the hardware has to verify the bandwidth requirements. (Maybe some other SuperSpeed controller design also cares, but if so then this change is unlikely to hurt.

Re: usb HC busted?

2018-07-19 Thread Alan Stern
n for the new altsetting to be performed before the old altsetting has been disabled, and the xHCI hardware can't do this. We may need to change the core so that the old endpoints are disabled before the bandwidth check is done, instead of after. Of course, this leads to an awkward situation if th

Re: usb HC busted?

2018-07-17 Thread Alan Stern
On Tue, 17 Jul 2018, Sudip Mukherjee wrote: > On Tue, Jul 17, 2018 at 03:40:22PM +0100, Sudip Mukherjee wrote: > > Hi Alan, > > > > On Tue, Jul 17, 2018 at 10:28:14AM -0400, Alan Stern wrote: > > > On Tue, 17 Jul 2018, Sudip Mukherjee wrote: > > > &g

Re: usb HC busted?

2018-07-17 Thread Alan Stern
to... > + */ > + return 0; > + } > + > /* Make sure we have enough bandwidth for this alternate interface. >* Remove the current alt setting and add the new alt setting. > */ No, neither of these is right. It's possible to use usb_set_inte

Re: usb HC busted?

2018-07-17 Thread Alan Stern
lthough a comment refers to it. Maybe this is the real problem? Alan Stern > But then usb_set_interface() continues and > calls usb_disable_interface() -> usb_hcd_flush_endpoint()->unlink1()-> > xhci_urb_dequeue() which at the end gives the command to stop endpoint. > >

Re: WARN_ON(irqs_disabled()) in dma_free_attrs?

2018-03-04 Thread Alan Stern
On Sun, 4 Mar 2018, Fredrik Noring wrote: > Hi Alan Stern, > > > > Alan, can dma_free_coherent be delayed to a point when IRQs are enabled? > > > > Yes, subject to the usual concerns about not being delayed for too > > long. Also, some HCDs are highly

Re: WARN_ON(irqs_disabled()) in dma_free_attrs?

2018-03-04 Thread Alan Stern
lso, some HCDs are highly memory-constrained. I don't know if they use this API, but if they do then delaying a free could result in not enough memory being available when an allocation is needed. Alan Stern ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu

Error: DMA: Out of SW-IOMMU space [was: External USB drives become unresponsive after few hours.]

2015-04-16 Thread Alan Stern
mailing lists. Alan Stern ___ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu