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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32238C4360C for ; Fri, 4 Oct 2019 12:27:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 05056222C7 for ; Fri, 4 Oct 2019 12:27:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=googlemail.com header.i=@googlemail.com header.b="KtOZZQLW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730745AbfJDM14 (ORCPT ); Fri, 4 Oct 2019 08:27:56 -0400 Received: from mail-ua1-f65.google.com ([209.85.222.65]:43697 "EHLO mail-ua1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730606AbfJDM1x (ORCPT ); Fri, 4 Oct 2019 08:27:53 -0400 Received: by mail-ua1-f65.google.com with SMTP id k24so1962929uag.10; Fri, 04 Oct 2019 05:27:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=wSaY7W6VdgweKOp9jTYZreYJLfH4I8nv1hwYNYCfNYk=; b=KtOZZQLWCS4cSkTOhxNhKpVdlgScCqqd1k9O1sOLLv3yWqmzDmWQCdv8SbIdZBoMW1 p+XTPTLA1kfle7EHLlKSnLYcUlzSuqJptOPqafa3svn7Hf80RAA2Cx71KzunAZVY5CKI 8ojxRA8Gp9JZxvfYXIFcqiBo5VkICsvGOOLms+dAmKNc2Gyb1ABs5C4J6QthrMsOZNdB mA5kWsr4Hs0Zx6aJQedGIHQBYMfbbCdUocr8j9BalA5nxZKpqtZiAC0qFj6rsGSkNaVO NBFkJf8d9O/ZSW6P4AaWH+j1E+rTmA4hXSMSg0moPcRF/G6BePZfF5CN15CA+rHi0N3V MILQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=wSaY7W6VdgweKOp9jTYZreYJLfH4I8nv1hwYNYCfNYk=; b=mtlLCuTCcBLd05SOXYG8dYN1SnnX2nuGNWkEGT8e9CSLzbeyAO5hFA5xIlha4VUN+L ox0TwflDvulY3lwc5omUCkWW+yg6HpwYdZPdyQHocYSPmHL2Xz2vePYQWu9JdevbPG/k J3If6Pkrnx4kopnrYSdbJpCY2kdKtNRpPc0SCjHkk+DllXhALIDHpCzhmpgcsLTe2ifv I+Ur6SxmXqcwiZPtE5Vp8HUbcXq8qb0cOfYAwOd1oiaq1YbDUvVM+B3dBA63EzGVAyyl OAqHDIXthDflIOk2AmdbvBqXLOxO6PNYxzWF/pjRXFOihDDTxI20tiz+oq62csuIcxEa jSCQ== X-Gm-Message-State: APjAAAV/TQbYXSW9CD0HgYtFdK0/dskZBuvQApVkhOp4jGCOvYfNtZwq 02/RaAtxq3HJq/Vff5EvI6kySIr7U3T/BJpZ3vQ= X-Google-Smtp-Source: APXvYqyUkWxXFI6t/ssjecMpUlOsdFzkDM1l5GdegvctcVigKJWMkEH5L7iuW0BTIlwrQde45JWQ1TaHnD69ETrLuPE= X-Received: by 2002:ab0:2397:: with SMTP id b23mr317737uan.91.1570192072150; Fri, 04 Oct 2019 05:27:52 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Yegor Yefremov Date: Fri, 4 Oct 2019 14:27:39 +0200 Message-ID: Subject: Re: DM3730 Bluetooth Performance differences between SERIAL_8250_OMAP vs SERIAL_OMAP To: Adam Ford Cc: Greg Kroah-Hartman , Jiri Slaby , linux-serial@vger.kernel.org, Linux Kernel Mailing List , Linux-OMAP , Vignesh R Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Adam, On Fri, Oct 4, 2019 at 12:39 PM Adam Ford wrote: > > On Fri, Oct 4, 2019 at 5:02 AM Adam Ford wrote: > > > > I am running Kernel 5.3.2 trying to troubleshoot some intermittent > > Bluetooth issues, and I think I have narrowed it down to the serial > > driver in use. > > I should have also noted that it's using UART2 with CTS and RTS on the > DM3730 (omap3630) and its configured with a baud rate of 3M. > I tried slowing it to 115200, but that didn't help. I tried disabling > the DMA hooks from the device tree, and that didn't help. > > > By default, omap2plus_defconfig enables both SERIAL_8250_OMAP and > > SERIAL_OMAP. I have my console device configured as ttyS0, and all > > appears fine. When I enable Bluetooth, however, I get intermittent > > errors on an DM3730 / OMAP3630. > > > > Using the 8250 driver for Blueotooth I get intermittent frame errors > > and data loss. > > > > Scanning ... > > [ 28.482452] Bluetooth: hci0: Frame reassembly failed (-84) > > [ 36.162170] Bluetooth: hci0: Frame reassembly failed (-84) > > F4:4E:FC:C9:2F:57 BluJax > > # l2ping F4:4E:FC:C9:2F:57 > > Ping: F4:4E:FC:C9:2F:57 from 00:18:30:49:7D:63 (data size 44) ... > > 44 bytes from F4:4E:FC:C9:2F:57 id 0 time 8.27ms > > no response from F4:4E:FC:C9:2F:57: id 1 > > ^C2 sent, 1 received, 50% loss > > > > (after a fairly long hang, I hit control-c) > > > > However, disabling the 8250 driver and using the only SERIAL_OMAP and > > the console routed to ttyO0, the Bluetooth works well, so I believe it > > to be a serial driver issue and not a Bluetooth error. > > > > # hcitool scan > > Scanning ... > > F4:4E:FC:C9:2F:57 BluJax > > ^C > > # l2ping F4:4E:FC:C9:2F:57 > > Ping: F4:4E:FC:C9:2F:57 from 00:18:30:49:7D:63 (data size 44) ... > > 44 bytes from F4:4E:FC:C9:2F:57 id 0 time 6.90ms > > ... > > 44 bytes from F4:4E:FC:C9:2F:57 id 14 time 28.29ms > > ^C15 sent, 15 received, 0% loss > > # > > > > 0% loss and regular, repeatable communication without any Frame > > reassembly errors. > > > > I tried disabling SERIAL_OMAP and using only SERIAL_8250_OMAP, but > that didn't help. Because the issue goes away when I disable > SERIAL_8250_OMAP, I am wondering if something is either being > misconfigured or some IRQ or DMA integration is missing that may be > present with the older SERIAL_OMAP driver. > > > Any suggestions on how to troubleshoot or what might cause the > > difference between the two drivers? Can it be related to this issue [1]? Can you confirm that 5.2 is working as expected with the 8250 driver? [1] https://marc.info/?l=linux-serial&m=156965039008649&w=2 Cheers, Yegor