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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 1C233C432C3 for ; Tue, 3 Dec 2019 22:40:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E34032084F for ; Tue, 3 Dec 2019 22:40:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575412827; bh=Rpgx27oaH5pyEEWNHINeAj4AJ8nZJiR6iAKPlroSPAw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=oSU+EVXF5aaM0LvfPuhI2Uw9Vd35ZvBPaPfY8BpBi34SXRelo5BGRi6etjw/gP4S4 Ky/lFpFFwnBsr7p+XfZcpLOgcrdmYe5pkQ2u8PsKI/gtatIk7LgkS7Ed1KPRqSPloR Nqn6mY7FkAU1WBPGqVui3WIXUcUZmQehCaA0w2wA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727903AbfLCWkZ (ORCPT ); Tue, 3 Dec 2019 17:40:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:52596 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727870AbfLCWkT (ORCPT ); Tue, 3 Dec 2019 17:40:19 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E773E20684; Tue, 3 Dec 2019 22:40:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575412818; bh=Rpgx27oaH5pyEEWNHINeAj4AJ8nZJiR6iAKPlroSPAw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iuSfk10Q8BlBYor7c8cX2lJ88MQv8lMQTuzcVudnD88kY9dJQxsFe+gOoj7jTGDbX t3kLo3rw7s5qKh+0sX3N3irdU+91dt75PQbQVY/aXvnL2IktiV7JQ+xvKmNAb8a09N U0hJ6hF9Dj8JLngBv7ZTqblcejp+C0iJ5GVidwco= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Alexandre Belloni , Stephen Boyd , Sasha Levin Subject: [PATCH 5.3 028/135] clk: at91: avoid sleeping early Date: Tue, 3 Dec 2019 23:34:28 +0100 Message-Id: <20191203213011.487609855@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191203213005.828543156@linuxfoundation.org> References: <20191203213005.828543156@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alexandre Belloni [ Upstream commit 658fd65cf0b0d511de1718e48d9a28844c385ae0 ] It is not allowed to sleep to early in the boot process and this may lead to kernel issues if the bootloader didn't prepare the slow clock and main clock. This results in the following error and dump stack on the AriettaG25: bad: scheduling from the idle thread! Ensure it is possible to sleep, else simply have a delay. Reported-by: Uwe Kleine-König Signed-off-by: Alexandre Belloni Link: https://lkml.kernel.org/r/20190920153906.20887-1-alexandre.belloni@bootlin.com Fixes: 80eded6ce8bb ("clk: at91: add slow clks driver") Tested-by: Uwe Kleine-König Signed-off-by: Stephen Boyd Signed-off-by: Sasha Levin --- drivers/clk/at91/clk-main.c | 5 ++++- drivers/clk/at91/sckc.c | 20 ++++++++++++++++---- 2 files changed, 20 insertions(+), 5 deletions(-) diff --git a/drivers/clk/at91/clk-main.c b/drivers/clk/at91/clk-main.c index 311cea0c3ae2b..54b2b2dd2bb57 100644 --- a/drivers/clk/at91/clk-main.c +++ b/drivers/clk/at91/clk-main.c @@ -297,7 +297,10 @@ static int clk_main_probe_frequency(struct regmap *regmap) regmap_read(regmap, AT91_CKGR_MCFR, &mcfr); if (mcfr & AT91_PMC_MAINRDY) return 0; - usleep_range(MAINF_LOOP_MIN_WAIT, MAINF_LOOP_MAX_WAIT); + if (system_state < SYSTEM_RUNNING) + udelay(MAINF_LOOP_MIN_WAIT); + else + usleep_range(MAINF_LOOP_MIN_WAIT, MAINF_LOOP_MAX_WAIT); } while (time_before(prep_time, timeout)); return -ETIMEDOUT; diff --git a/drivers/clk/at91/sckc.c b/drivers/clk/at91/sckc.c index 9bfe9a28294a7..fac0ca56d42d9 100644 --- a/drivers/clk/at91/sckc.c +++ b/drivers/clk/at91/sckc.c @@ -76,7 +76,10 @@ static int clk_slow_osc_prepare(struct clk_hw *hw) writel(tmp | osc->bits->cr_osc32en, sckcr); - usleep_range(osc->startup_usec, osc->startup_usec + 1); + if (system_state < SYSTEM_RUNNING) + udelay(osc->startup_usec); + else + usleep_range(osc->startup_usec, osc->startup_usec + 1); return 0; } @@ -187,7 +190,10 @@ static int clk_slow_rc_osc_prepare(struct clk_hw *hw) writel(readl(sckcr) | osc->bits->cr_rcen, sckcr); - usleep_range(osc->startup_usec, osc->startup_usec + 1); + if (system_state < SYSTEM_RUNNING) + udelay(osc->startup_usec); + else + usleep_range(osc->startup_usec, osc->startup_usec + 1); return 0; } @@ -288,7 +294,10 @@ static int clk_sam9x5_slow_set_parent(struct clk_hw *hw, u8 index) writel(tmp, sckcr); - usleep_range(SLOWCK_SW_TIME_USEC, SLOWCK_SW_TIME_USEC + 1); + if (system_state < SYSTEM_RUNNING) + udelay(SLOWCK_SW_TIME_USEC); + else + usleep_range(SLOWCK_SW_TIME_USEC, SLOWCK_SW_TIME_USEC + 1); return 0; } @@ -533,7 +542,10 @@ static int clk_sama5d4_slow_osc_prepare(struct clk_hw *hw) return 0; } - usleep_range(osc->startup_usec, osc->startup_usec + 1); + if (system_state < SYSTEM_RUNNING) + udelay(osc->startup_usec); + else + usleep_range(osc->startup_usec, osc->startup_usec + 1); osc->prepared = true; return 0; -- 2.20.1