From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3404C3DA78 for ; Tue, 17 Jan 2023 15:41:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232920AbjAQPli (ORCPT ); Tue, 17 Jan 2023 10:41:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39804 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233548AbjAQPke (ORCPT ); Tue, 17 Jan 2023 10:40:34 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1C33841B7E for ; Tue, 17 Jan 2023 07:38:15 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CAB81B81673 for ; Tue, 17 Jan 2023 15:38:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 01EF4C433D2; Tue, 17 Jan 2023 15:38:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1673969892; bh=KZfNFfExBRKW3vmV5CqMjuGmAvR2sfVi9GPv5FLj9Fk=; h=Subject:To:From:Date:From; b=F7Bn13z2JygVfzhnAWip96XsSqKvkJ+cRjX0ZmsJc8xMgE6rZ5ihRvMePPqudcjBP EBk5jf3rFvM8H7+Q8mRZczXmdvkUH8JvflDad6TpdlrOEmqAecsHkyyUa2Lrnma5hy yA4zbKaA6jZlIBAFd9EV3eUqzDqmxa5qIAIrjuAQ= Subject: patch "usb: cdns3: remove fetched trb from cache before dequeuing" added to usb-linus To: pawell@cadence.com, gregkh@linuxfoundation.org, peter.chen@kernel.org, stable@vger.kernel.org From: Date: Tue, 17 Jan 2023 16:38:10 +0100 Message-ID: <1673969890247247@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled usb: cdns3: remove fetched trb from cache before dequeuing to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From 1301c7b9f7efad2f11ef924e317c18ebd714fc9a Mon Sep 17 00:00:00 2001 From: Pawel Laszczak Date: Tue, 15 Nov 2022 05:00:39 -0500 Subject: usb: cdns3: remove fetched trb from cache before dequeuing After doorbell DMA fetches the TRB. If during dequeuing request driver changes NORMAL TRB to LINK TRB but doesn't delete it from controller cache then controller will handle cached TRB and packet can be lost. The example scenario for this issue looks like: 1. queue request - set doorbell 2. dequeue request 3. send OUT data packet from host 4. Device will accept this packet which is unexpected 5. queue new request - set doorbell 6. Device lost the expected packet. By setting DFLUSH controller clears DRDY bit and stop DMA transfer. Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver") cc: Signed-off-by: Pawel Laszczak Acked-by: Peter Chen Link: https://lore.kernel.org/r/20221115100039.441295-1-pawell@cadence.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/cdns3/cdns3-gadget.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-gadget.c index 5adcb349718c..ccfaebca6faa 100644 --- a/drivers/usb/cdns3/cdns3-gadget.c +++ b/drivers/usb/cdns3/cdns3-gadget.c @@ -2614,6 +2614,7 @@ int cdns3_gadget_ep_dequeue(struct usb_ep *ep, u8 req_on_hw_ring = 0; unsigned long flags; int ret = 0; + int val; if (!ep || !request || !ep->desc) return -EINVAL; @@ -2649,6 +2650,13 @@ int cdns3_gadget_ep_dequeue(struct usb_ep *ep, /* Update ring only if removed request is on pending_req_list list */ if (req_on_hw_ring && link_trb) { + /* Stop DMA */ + writel(EP_CMD_DFLUSH, &priv_dev->regs->ep_cmd); + + /* wait for DFLUSH cleared */ + readl_poll_timeout_atomic(&priv_dev->regs->ep_cmd, val, + !(val & EP_CMD_DFLUSH), 1, 1000); + link_trb->buffer = cpu_to_le32(TRB_BUFFER(priv_ep->trb_pool_dma + ((priv_req->end_trb + 1) * TRB_SIZE))); link_trb->control = cpu_to_le32((le32_to_cpu(link_trb->control) & TRB_CYCLE) | @@ -2660,6 +2668,10 @@ int cdns3_gadget_ep_dequeue(struct usb_ep *ep, cdns3_gadget_giveback(priv_ep, priv_req, -ECONNRESET); + req = cdns3_next_request(&priv_ep->pending_req_list); + if (req) + cdns3_rearm_transfer(priv_ep, 1); + not_found: spin_unlock_irqrestore(&priv_dev->lock, flags); return ret; -- 2.39.0