From patchwork Wed Aug 17 12:35:28 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roger Quadros X-Patchwork-Id: 74105 Delivered-To: patch@linaro.org Received: by 10.140.29.52 with SMTP id a49csp2486445qga; Wed, 17 Aug 2016 05:35:49 -0700 (PDT) X-Received: by 10.66.142.197 with SMTP id ry5mr103911pab.143.1471437349543; Wed, 17 Aug 2016 05:35:49 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id u2si37566469paw.283.2016.08.17.05.35.48; Wed, 17 Aug 2016 05:35:49 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752899AbcHQMfq (ORCPT + 27 others); Wed, 17 Aug 2016 08:35:46 -0400 Received: from bear.ext.ti.com ([198.47.19.11]:53313 "EHLO bear.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752353AbcHQMfp (ORCPT ); Wed, 17 Aug 2016 08:35:45 -0400 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id u7HCZZRt030464; Wed, 17 Aug 2016 07:35:35 -0500 Received: from DFLE73.ent.ti.com (dfle73.ent.ti.com [128.247.5.110]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id u7HCZZ1R022691; Wed, 17 Aug 2016 07:35:35 -0500 Received: from dflp33.itg.ti.com (10.64.6.16) by DFLE73.ent.ti.com (128.247.5.110) with Microsoft SMTP Server id 14.3.294.0; Wed, 17 Aug 2016 07:35:35 -0500 Received: from lta0400828d.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp33.itg.ti.com (8.14.3/8.13.8) with ESMTP id u7HCZWYG005279; Wed, 17 Aug 2016 07:35:33 -0500 From: Roger Quadros To: , CC: , , , , Roger Quadros Subject: [PATCH] usb: core: setup dma_pfn_offset for USB devices Date: Wed, 17 Aug 2016 15:35:28 +0300 Message-ID: <1471437328-8621-1-git-send-email-rogerq@ti.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If dma_pfn_offset is not inherited correctly from the host controller, it might result in sub-optimal configuration as bounce buffer limit might be set to less than optimal level. e.g. On Keystone 2 systems, dma_max_pfn() is 0x87FFFF and dma_mask_pfn is 0xFFFFF. Consider a mass storage use case: Without this patch, usb scsi host device (usb-storage) will get a dma_pfn_offset of 0 resulting in a dma_max_pfn() of 0xFFFFF within the scsi layer (scsi_calculate_bounce_limit()). This will result in bounce buffers being unnecessarily used. Hint: On 32-bit ARM platforms dma_max_pfn() = dma_mask_pfn + dma_pfn_offset Signed-off-by: Roger Quadros --- drivers/usb/core/message.c | 1 + drivers/usb/core/usb.c | 1 + 2 files changed, 2 insertions(+) -- 2.7.4 diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index 0406a59..6856b7a 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -1863,6 +1863,7 @@ free_interfaces: intf->dev.type = &usb_if_device_type; intf->dev.groups = usb_interface_groups; intf->dev.dma_mask = dev->dev.dma_mask; + intf->dev.dma_pfn_offset = dev->dev.dma_pfn_offset; INIT_WORK(&intf->reset_ws, __usb_queue_reset_device); intf->minor = -1; device_initialize(&intf->dev); diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index 5e80697..d81791a 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -441,6 +441,7 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, dev->dev.type = &usb_device_type; dev->dev.groups = usb_device_groups; dev->dev.dma_mask = bus->controller->dma_mask; + dev->dev.dma_pfn_offset = bus->controller->dma_pfn_offset; set_dev_node(&dev->dev, dev_to_node(bus->controller)); dev->state = USB_STATE_ATTACHED; dev->lpm_disable_count = 1;