From patchwork Thu Sep 10 02:51:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Packham X-Patchwork-Id: 11766427 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 40035139F for ; Thu, 10 Sep 2020 02:52:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1FF1B21D40 for ; Thu, 10 Sep 2020 02:52:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=alliedtelesis.co.nz header.i=@alliedtelesis.co.nz header.b="Dl/XEoko" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727870AbgIJCwh (ORCPT ); Wed, 9 Sep 2020 22:52:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60222 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730067AbgIJCwH (ORCPT ); Wed, 9 Sep 2020 22:52:07 -0400 Received: from gate2.alliedtelesis.co.nz (gate2.alliedtelesis.co.nz [IPv6:2001:df5:b000:5::4]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D1AF8C061573 for ; Wed, 9 Sep 2020 19:52:04 -0700 (PDT) Received: from mmarshal3.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id 1A5A4806B5; Thu, 10 Sep 2020 14:51:57 +1200 (NZST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1599706317; bh=lQhwDjP6TNS2Ik4pBM/Zgt2mpKx73CO14Av4nyUHdV0=; h=From:To:Cc:Subject:Date; b=Dl/XEokogax91p9/0956kDDlgva9mRwc6HTUWXhpsAx/lat3/xlutBsKDpTbVFWC+ hEqYYP8vF8ISmzC94Pm95DB9GaK6kbZPV7bmxh3VPQ8bJ9G4MZPsQAYj2q/YP3Fvvy 5rhUcg450FlhWEg2KjGFKj2+UqY8YVrXWFHPlOwW7bOnTguhu/UZ38UI9mbNUfxCGm SQWEz2GE+v8eUwQ9RtC0Q3qPlsJbPPdnp1OHNglBnUDvFHltRAqhmMRtgbmKJegVJE JY+wniQ5CRYWMsjy6Nlo6VrwPzrNKYIftExZxiGh5lX128w3ORRTtkVVeYwmi17N42 t1rHCz85oJdJA== Received: from smtp (Not Verified[10.32.16.33]) by mmarshal3.atlnz.lc with Trustwave SEG (v7,5,8,10121) id ; Thu, 10 Sep 2020 14:51:56 +1200 Received: from chrisp-dl.ws.atlnz.lc (chrisp-dl.ws.atlnz.lc [10.33.22.20]) by smtp (Postfix) with ESMTP id DC6C913EEBA; Thu, 10 Sep 2020 14:51:55 +1200 (NZST) Received: by chrisp-dl.ws.atlnz.lc (Postfix, from userid 1030) id C3FE5280076; Thu, 10 Sep 2020 14:51:56 +1200 (NZST) From: Chris Packham To: stern@rowland.harvard.edu, linux@prisktech.co.nz, gregkh@linuxfoundation.org Cc: linux-usb@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Chris Packham Subject: [PATCH] usb: host: ehci-platform: Add workaround for brcm,xgs-iproc-ehci Date: Thu, 10 Sep 2020 14:51:53 +1200 Message-Id: <20200910025154.20848-1-chris.packham@alliedtelesis.co.nz> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 x-atlnz-ls: pat Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org The ehci controller found in some Broadcom switches with integrated SoCs has an issue which causes a soft lockup with large transfers like you see when running ext4 on USB3 flash drive. Port the fix from the Broadcom XLDK to increase the OUT_THRESHOLD to avoid the problem. Signed-off-by: Chris Packham --- I don't have much data on what this change does. I can say it is needed to avoid a soft lockup when using a USB3 Flash drive formatted has ext4 (USB2 + ext4 is OK, USB3 + fat is OK). I presume the affected combination ends up using larger transfers triggering the problem. The equivalent change in the Broadcom XLDK is if (IS_ENABLED(CONFIG_USB_EHCI_XGS_IPROC)) ehci_writel(ehci, BCM_USB_FIFO_THRESHOLD, &ehci->regs->reserved4[6]); This is problematic because it would unconditionally apply to all ehci controllers whenever CONFIG_USB_EHCI_XGS_IPROC is enabled (also reserved4 only goes to 6 so technically it's indexing off the end of the array). I wasn't sure if I should add a new property or somehow detect the affected host controller. I settled on using of_device_is_compatible() as that seemed the simplest thing to do. drivers/usb/host/ehci-platform.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/usb/host/ehci-platform.c b/drivers/usb/host/ehci-platform.c index 006c4f6188a5..0d2de8faa3c1 100644 --- a/drivers/usb/host/ehci-platform.c +++ b/drivers/usb/host/ehci-platform.c @@ -53,6 +53,9 @@ struct ehci_platform_priv { static const char hcd_name[] = "ehci-platform"; +#define bcm_iproc_insnreg01 hostpc +#define BCM_USB_FIFO_THRESHOLD 0x00800040 + static int ehci_platform_reset(struct usb_hcd *hcd) { struct platform_device *pdev = to_platform_device(hcd->self.controller); @@ -358,6 +361,9 @@ static int ehci_platform_probe(struct platform_device *dev) device_wakeup_enable(hcd->self.controller); device_enable_async_suspend(hcd->self.controller); + if (of_device_is_compatible(dev->dev.of_node, "brcm,xgs-iproc-ehci")) + ehci_writel(ehci, BCM_USB_FIFO_THRESHOLD, + ehci->regs->bcm_iproc_insnreg01); platform_set_drvdata(dev, hcd); if (priv->quirk_poll)