From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757838AbdJKN5D (ORCPT ); Wed, 11 Oct 2017 09:57:03 -0400 Received: from foss.arm.com ([217.140.101.70]:33100 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757639AbdJKN5C (ORCPT ); Wed, 11 Oct 2017 09:57:02 -0400 From: Robin Murphy To: mathias.nyman@intel.com, gregkh@linuxfoundation.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, hch@lst.de, m.szyprowski@samsung.com, iommu@lists.linux-foundation.org Subject: [PATCH] xhci: Set DMA parameters appropriately Date: Wed, 11 Oct 2017 14:56:56 +0100 Message-Id: <347776be09eb0ca947c1c8ced46ee3ca92d92e28.1507730115.git.robin.murphy@arm.com> X-Mailer: git-send-email 2.13.4.dirty Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org xHCI requires that data buffers do not cross 64KB boundaries (and are thus at most 64KB long as well) - whilst xhci_queue_{bulk,isoc}_tx() already split their input buffers into individual TRBs as necessary, it's still a good idea to advertise the limitations via the standard DMA API mechanism, so that most producers like the block layer and the DMA mapping implementations can lay things out correctly to begin with. Signed-off-by: Robin Murphy --- drivers/usb/host/xhci.c | 4 ++++ drivers/usb/host/xhci.h | 3 +++ 2 files changed, 7 insertions(+) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 74b4500641c2..1e7e1e3d8c48 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -4883,6 +4883,10 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks) dma_set_coherent_mask(dev, DMA_BIT_MASK(32)); } + dev->dma_parms = &xhci->dma_parms; + dma_set_max_seg_size(dev, SZ_64K); + dma_set_seg_boundary(dev, SZ_64K - 1); + xhci_dbg(xhci, "Calling HCD init\n"); /* Initialize HCD and host controller data structures. */ retval = xhci_init(hcd); diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 7ef69ea0b480..afcae4cc908d 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1767,6 +1767,9 @@ struct xhci_hcd { struct dma_pool *small_streams_pool; struct dma_pool *medium_streams_pool; + /* DMA alignment restrictions */ + struct device_dma_parameters dma_parms; + /* Host controller watchdog timer structures */ unsigned int xhc_state; -- 2.13.4.dirty