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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 3F5F9C433DB for ; Thu, 18 Feb 2021 16:01:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D953B64E0F for ; Thu, 18 Feb 2021 16:01:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232981AbhBRP7x (ORCPT ); Thu, 18 Feb 2021 10:59:53 -0500 Received: from muru.com ([72.249.23.125]:35044 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231764AbhBRN05 (ORCPT ); Thu, 18 Feb 2021 08:26:57 -0500 Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id CBEA2814A; Thu, 18 Feb 2021 13:24:56 +0000 (UTC) From: Tony Lindgren To: linux-omap@vger.kernel.org Cc: Dave Gerlach , Faiz Abbas , Santosh Shilimkar , Suman Anna , Tero Kristo , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Yongqin Liu Subject: [PATCH] soc: ti: omap-prm: Fix occasional abort on reset deassert for dra7 iva Date: Thu, 18 Feb 2021 15:24:26 +0200 Message-Id: <20210218132426.46155-1-tony@atomide.com> X-Mailer: git-send-email 2.30.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On reset deassert, we must wait a bit after the rstst bit change before we allow clockdomain autoidle again. Otherwise we get the following oops sometimes on dra7 with iva: Unhandled fault: imprecise external abort (0x1406) at 0x00000000 44000000.ocp:L3 Standard Error: MASTER MPU TARGET IVA_CONFIG (Read Link): At Address: 0x0005A410 : Data Access in User mode during Functional access Internal error: : 1406 [#1] SMP ARM ... (sysc_write_sysconfig) from [] (sysc_enable_module+0xcc/0x260) (sysc_enable_module) from [] (sysc_runtime_resume+0xc8/0x174) (sysc_runtime_resume) from [] (genpd_runtime_resume+0x94/0x224) (genpd_runtime_resume) from [] (__rpm_callback+0xd8/0x180) It is unclear what all devices this might affect, but presumably other devices with the rstst bit too can be affected. So let's just enable the delay for all the devices with rstst bit for now. Later on we may want to limit the list to the know affected devices if needed. Fixes: d30cd83f6853 ("soc: ti: omap-prm: add support for denying idle for reset clockdomain") Reported-by: Yongqin Liu Signed-off-by: Tony Lindgren --- drivers/soc/ti/omap_prm.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/soc/ti/omap_prm.c b/drivers/soc/ti/omap_prm.c --- a/drivers/soc/ti/omap_prm.c +++ b/drivers/soc/ti/omap_prm.c @@ -830,8 +830,12 @@ static int omap_reset_deassert(struct reset_controller_dev *rcdev, reset->prm->data->name, id); exit: - if (reset->clkdm) + if (reset->clkdm) { + /* At least dra7 iva needs a delay before clkdm idle */ + if (has_rstst) + udelay(1); pdata->clkdm_allow_idle(reset->clkdm); + } return ret; } -- 2.30.1