From patchwork Thu Nov 17 09:48:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sarthak Garg X-Patchwork-Id: 626750 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 D6879C433FE for ; Thu, 17 Nov 2022 09:49:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234629AbiKQJtb (ORCPT ); Thu, 17 Nov 2022 04:49:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37758 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230344AbiKQJt3 (ORCPT ); Thu, 17 Nov 2022 04:49:29 -0500 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0C19BB877; Thu, 17 Nov 2022 01:49:28 -0800 (PST) Received: from pps.filterd (m0279862.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 2AH935J3001073; Thu, 17 Nov 2022 09:49:17 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id; s=qcppdkim1; bh=mXyp3kuz6+raj/Kj/BPH6q/i8EriXCANwM6ExVdaBaY=; b=eC1sBSIAa4z0dgRUSgCpnx+p5g4R277LLYvaw1SMqJpOxDMK0gb9wQGK378zCE2HSlBq wYI/tnV9m6dZmL1epc+yN3/Xt7xguHWAD7wlz8PFNl7KNeaUm77ZdFe7m6+xJcX+LfqE mveOL4KBNemPwIP900G9l9fMM754oV6XmqJ26EC34cpae0SyqhQPLsO7AwVd2wlKAh+G NkcafyIhdRRhXEFFQ8jdj0r2phRZ2fLQGhYEcAKxg5flS55Gl31tmCt36ALJdbV35yvq ZA8JzAHjwdctVtK9cqwzdnSt5VBBpbyKpBw94+1Q/TxoECFc616fpBg+qJQF0HEQuUCf cw== Received: from apblrppmta01.qualcomm.com (blr-bdr-fw-01_GlobalNAT_AllZones-Outside.qualcomm.com [103.229.18.19]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3kwfcb0hc4-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 17 Nov 2022 09:49:17 +0000 Received: from pps.filterd (APBLRPPMTA01.qualcomm.com [127.0.0.1]) by APBLRPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTP id 2AH9nCJ3014247; Thu, 17 Nov 2022 09:49:12 GMT Received: from pps.reinject (localhost [127.0.0.1]) by APBLRPPMTA01.qualcomm.com (PPS) with ESMTPS id 3kt4jm2fk8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Thu, 17 Nov 2022 09:49:12 +0000 Received: from APBLRPPMTA01.qualcomm.com (APBLRPPMTA01.qualcomm.com [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 2AH9nCG9014241; Thu, 17 Nov 2022 09:49:12 GMT Received: from hu-maiyas-hyd.qualcomm.com (hu-sartgarg-hyd.qualcomm.com [10.213.105.147]) by APBLRPPMTA01.qualcomm.com (PPS) with ESMTP id 2AH9nC8w014240; Thu, 17 Nov 2022 09:49:12 +0000 Received: by hu-maiyas-hyd.qualcomm.com (Postfix, from userid 2339771) id 8A9495001D8; Thu, 17 Nov 2022 15:19:11 +0530 (+0530) From: Sarthak Garg To: adrian.hunter@intel.com, ulf.hansson@linaro.org Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, quic_rampraka@quicinc.com, quic_pragalla@quicinc.com, quic_sayalil@quicinc.com, Sarthak Garg , Wolfram Sang , "Darrick J. Wong" , "Jason A. Donenfeld" , Greg Kroah-Hartman , Shaik Sajida Bhanu Subject: [PATCH V1] mmc: core: Wait for 1ms after enabling the clocks post voltage switch Date: Thu, 17 Nov 2022 15:18:48 +0530 Message-Id: <20221117094859.20582-1-quic_sartgarg@quicinc.com> X-Mailer: git-send-email 2.17.1 X-QCInternal: smtphost X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: E8iSzsCjZO6PhuCyrhhC2LzKyzTpc9z0 X-Proofpoint-GUID: E8iSzsCjZO6PhuCyrhhC2LzKyzTpc9z0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-11-17_06,2022-11-16_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1011 bulkscore=0 mlxscore=0 lowpriorityscore=0 adultscore=0 priorityscore=1501 mlxlogscore=999 impostorscore=0 spamscore=0 malwarescore=0 phishscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2210170000 definitions=main-2211170075 Precedence: bulk List-ID: X-Mailing-List: linux-mmc@vger.kernel.org As per spec we should wait for 1ms after providing the SD clock to the card again as part of voltage switch sequence but there seems to be a violation here. Clocks are getting gated before 1ms as part of sdhci_set_ios function where we try to reset SD Clock Enable by resetting SDHCI_CLOCK_CARD_EN bit in SDHCI_CLOCK_CONTROL register leading to voltage switch failures for specific SD cards. Below ftraces also confirms the above understanding : 9.511367: mmc_host_set_uhs_voltage: mmc1 called 9.511369: mmc_set_ios: mmc1: clock 0Hz busmode 2 powermode 2 cs 0 Vdd 18 width 1 timing 0 9.511370: sdhci_set_ios: mmc1 called 9.511370: sdhci_set_ios: mmc1 setting clock ios->clock: 0 host->clock: 400000 9.511372: sdhci_msm_set_clock: mmc1 clock: 0 9.511394: sdhci_set_ios: mmc1 gating clocks by writing ~SDHCI_CLOCK_CARD_EN to SDHCI_CLOCK_CONTROL register 9.511413: sdhci_msm_set_clock: mmc1 clock: 0 9.511423: mmc_set_signal_voltage: mmc1 called 9.533816: mmc_set_ios: mmc1: clock 400000Hz busmode 2 powermode 2 cs 0 Vdd 18 width 1 timing 0 9.533820: sdhci_set_ios: mmc1 called 9.533822: sdhci_set_ios: mmc1 setting clock ios->clock: 400000 host->clock: 0 9.533826: sdhci_msm_set_clock: mmc1 clock: 400000 9.533925: sdhci_enable_clk: mmc1 Enabling clocks by writing SDHCI_CLOCK_CARD_EN to SDHCI_CLOCK_CONTROL register 9.533950: sdhci_set_ios: mmc1 gating clocks by writing ~SDHCI_CLOCK_CARD_EN to SDHCI_CLOCK_CONTROL register 9.533973: sdhci_msm_set_clock: mmc1 clock: 400000 9.534043: sdhci_enable_clk: mmc1 Enabling clocks by writing SDHCI_CLOCK_CARD_EN to SDHCI_CLOCK_CONTROL register 9.534045: mmc_host_set_uhs_voltage: mmc1 Done Wait for 1ms after enabling the clock post voltage switch to make sure clock is kept alive for alteast 1ms as per spec. Signed-off-by: Sarthak Garg --- drivers/mmc/core/core.c | 4 ++++ drivers/mmc/host/sdhci.c | 3 +++ include/linux/mmc/host.h | 1 + 3 files changed, 8 insertions(+) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index a1efda85c6f2..d63e00aab6cb 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -1181,6 +1181,8 @@ int mmc_host_set_uhs_voltage(struct mmc_host *host) host->ios.clock = 0; mmc_set_ios(host); + host->doing_signal_voltage_switch = true; + if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180)) return -EAGAIN; @@ -1189,6 +1191,8 @@ int mmc_host_set_uhs_voltage(struct mmc_host *host) host->ios.clock = clock; mmc_set_ios(host); + host->doing_signal_voltage_switch = false; + return 0; } diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index fb6e9a81f198..ac7c254eef4b 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -2312,6 +2312,9 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) host->ops->set_clock(host, ios->clock); host->clock = ios->clock; + if (mmc->doing_signal_voltage_switch) + usleep_range(1000, 1250); + if (host->quirks & SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK && host->clock) { host->timeout_clk = mmc->actual_clock ? diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 8fdd3cf971a3..06c88cd7a8bf 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -521,6 +521,7 @@ struct mmc_host { bool hsq_enabled; u32 err_stats[MMC_ERR_MAX]; + bool doing_signal_voltage_switch; unsigned long private[] ____cacheline_aligned; };