From patchwork Wed Jun 14 08:03:58 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 693505 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 5DCB1EB64DA for ; Wed, 14 Jun 2023 08:05:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229796AbjFNIF0 (ORCPT ); Wed, 14 Jun 2023 04:05:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243498AbjFNIE3 (ORCPT ); Wed, 14 Jun 2023 04:04:29 -0400 Received: from muru.com (muru.com [72.249.23.125]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 409291FFB; Wed, 14 Jun 2023 01:04:06 -0700 (PDT) Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id CA51C8027; Wed, 14 Jun 2023 08:04:04 +0000 (UTC) From: Tony Lindgren To: linux-omap@vger.kernel.org Cc: Dave Gerlach , Faiz Abbas , Greg Kroah-Hartman , Keerthy , Kevin Hilman , Nishanth Menon , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, "kernelci . org bot" Subject: [PATCH] bus: ti-sysc: Flush posted write on enable before reset Date: Wed, 14 Jun 2023 11:03:58 +0300 Message-ID: <20230614080358.51516-1-tony@atomide.com> X-Mailer: git-send-email 2.41.0 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org The am335x devices started producing boot errors for resetting musb module in because of subtle timing changes: Unhandled fault: external abort on non-linefetch (0x1008) ... sysc_poll_reset_sysconfig from sysc_reset+0x109/0x12 sysc_reset from sysc_probe+0xa99/0xeb0 ... The fix is to flush posted write after enable before reset during probe. Note that some devices also need to specify the delay after enable with ti,sysc-delay-us, but this is not needed for musb on am335x based on my tests. Reported-by: kernelci.org bot Closes: https://storage.kernelci.org/next/master/next-20230614/arm/multi_v7_defconfig+CONFIG_THUMB2_KERNEL=y/gcc-10/lab-cip/baseline-beaglebone-black.html Fixes: 596e7955692b ("bus: ti-sysc: Add support for software reset") Signed-off-by: Tony Lindgren --- drivers/bus/ti-sysc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/bus/ti-sysc.c b/drivers/bus/ti-sysc.c --- a/drivers/bus/ti-sysc.c +++ b/drivers/bus/ti-sysc.c @@ -2142,6 +2142,8 @@ static int sysc_reset(struct sysc *ddata) sysc_val = sysc_read_sysconfig(ddata); sysc_val |= sysc_mask; sysc_write(ddata, sysc_offset, sysc_val); + /* Flush posted write */ + sysc_val = sysc_read_sysconfig(ddata); } if (ddata->cfg.srst_udelay)