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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 B7B80C43381 for ; Fri, 22 Mar 2019 12:52:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 865AB218FE for ; Fri, 22 Mar 2019 12:52:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553259164; bh=grX2bnu+Nwhwj/5lAimFXl0InQlOYMtVi/84HW2l6Cw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=v32RhW4dE3x35t6d00Qks3YgpQiStATjc/Bgw0zM11MiD0IuFO2EuYk3Db/ODx/Pl XviHDu4GJxgrwbKq5N0laatnOD+cw2p9qu8q+tczuuaEQCmTcbmshTrsmgRP4YYB02 crkVNbbgT64mDOLCnJw0BbNMgeKw9ADs+mKOyAus= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732568AbfCVMwj (ORCPT ); Fri, 22 Mar 2019 08:52:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:57230 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729567AbfCVLxG (ORCPT ); Fri, 22 Mar 2019 07:53:06 -0400 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 293F02192D; Fri, 22 Mar 2019 11:53:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553255584; bh=grX2bnu+Nwhwj/5lAimFXl0InQlOYMtVi/84HW2l6Cw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=weasaZlDKi8AvEu2Q7tpi2qQ7E6xkUOjSLCcAh0tlfn0Rt428wVqY5ZfU5t952vwX eF3+RV6lTphg+d3nhqchRrXb+8QjKH1n1QFb1vbVsdCW8SM4ZSUTSQoQF0sZd3TP9B iBuuAxfSiNjz7ocLqdFrv2xDc4svjnIOTpHRsQ20= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Misael Lopez Cruz , Peter Ujfalusi , Tony Lindgren , Stephen Boyd Subject: [PATCH 4.14 117/183] clk: clk-twl6040: Fix imprecise external abort for pdmclk Date: Fri, 22 Mar 2019 12:15:45 +0100 Message-Id: <20190322111250.187233537@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190322111241.819468003@linuxfoundation.org> References: <20190322111241.819468003@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tony Lindgren commit 5ae51d67aec95f6f9386aa8dd5db424964895575 upstream. I noticed that modprobe clk-twl6040 can fail after a cold boot with: abe_cm:clk:0010:0: failed to enable ... Unhandled fault: imprecise external abort (0x1406) at 0xbe896b20 WARNING: CPU: 1 PID: 29 at drivers/clk/clk.c:828 clk_core_disable_lock+0x18/0x24 ... (clk_core_disable_lock) from [] (_disable_clocks+0x18/0x90) (_disable_clocks) from [] (_idle+0x17c/0x244) (_idle) from [] (omap_hwmod_idle+0x24/0x44) (omap_hwmod_idle) from [] (sysc_runtime_suspend+0x48/0x108) (sysc_runtime_suspend) from [] (__rpm_callback+0x144/0x1d8) (__rpm_callback) from [] (rpm_callback+0x20/0x80) (rpm_callback) from [] (rpm_suspend+0x120/0x694) (rpm_suspend) from [] (__pm_runtime_idle+0x60/0x84) (__pm_runtime_idle) from [] (sysc_probe+0x874/0xf2c) (sysc_probe) from [] (platform_drv_probe+0x48/0x98) After searching around for a similar issue, I came across an earlier fix that never got merged upstream in the Android tree for glass-omap-xrr02. There is patch "MFD: twl6040-codec: Implement PDMCLK cold temp errata" by Misael Lopez Cruz . Based on my observations, this fix is also needed when cold booting devices, and not just for deeper idle modes. Since we now have a clock driver for pdmclk, let's fix the issue in twl6040_pdmclk_prepare(). Cc: Misael Lopez Cruz Cc: Peter Ujfalusi Signed-off-by: Tony Lindgren Acked-by: Peter Ujfalusi Cc: Signed-off-by: Stephen Boyd Signed-off-by: Greg Kroah-Hartman --- drivers/clk/clk-twl6040.c | 53 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 51 insertions(+), 2 deletions(-) --- a/drivers/clk/clk-twl6040.c +++ b/drivers/clk/clk-twl6040.c @@ -41,6 +41,43 @@ static int twl6040_pdmclk_is_prepared(st return pdmclk->enabled; } +static int twl6040_pdmclk_reset_one_clock(struct twl6040_pdmclk *pdmclk, + unsigned int reg) +{ + const u8 reset_mask = TWL6040_HPLLRST; /* Same for HPPLL and LPPLL */ + int ret; + + ret = twl6040_set_bits(pdmclk->twl6040, reg, reset_mask); + if (ret < 0) + return ret; + + ret = twl6040_clear_bits(pdmclk->twl6040, reg, reset_mask); + if (ret < 0) + return ret; + + return 0; +} + +/* + * TWL6040A2 Phoenix Audio IC erratum #6: "PDM Clock Generation Issue At + * Cold Temperature". This affects cold boot and deeper idle states it + * seems. The workaround consists of resetting HPPLL and LPPLL. + */ +static int twl6040_pdmclk_quirk_reset_clocks(struct twl6040_pdmclk *pdmclk) +{ + int ret; + + ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_HPPLLCTL); + if (ret) + return ret; + + ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_LPPLLCTL); + if (ret) + return ret; + + return 0; +} + static int twl6040_pdmclk_prepare(struct clk_hw *hw) { struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk, @@ -48,8 +85,20 @@ static int twl6040_pdmclk_prepare(struct int ret; ret = twl6040_power(pdmclk->twl6040, 1); - if (!ret) - pdmclk->enabled = 1; + if (ret) + return ret; + + ret = twl6040_pdmclk_quirk_reset_clocks(pdmclk); + if (ret) + goto out_err; + + pdmclk->enabled = 1; + + return 0; + +out_err: + dev_err(pdmclk->dev, "%s: error %i\n", __func__, ret); + twl6040_power(pdmclk->twl6040, 0); return ret; }