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,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 94221C43462 for ; Wed, 31 Mar 2021 18:35:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F881610C7 for ; Wed, 31 Mar 2021 18:35:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235130AbhCaSfR (ORCPT ); Wed, 31 Mar 2021 14:35:17 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:34107 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235097AbhCaSfJ (ORCPT ); Wed, 31 Mar 2021 14:35:09 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1617215709; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=G2RTMQp5v7Cz0cfdeXg6D8y9jX6Ws/7gqaj2e8M+eXY=; b=P7p1MQl6Ng8KI9c9fIfaqQegWEV0q5cSt9iu9GY5GpY5ti/TLVpSZlez0I9jOz4u/KktbRU8 2ECA9xlsX1G9AgdonchpcQqs3AcpVLkJSXW7ESlfHuceHL4W3reYGAxh8E8OsoIAQsMynL8n sHhBlcATTohgrNU9AKHlFIo3Zlg= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n03.prod.us-east-1.postgun.com with SMTP id 6064c0be03cfff3452a5a356 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 31 Mar 2021 18:34:38 GMT Sender: bbhatt=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 6268EC433CA; Wed, 31 Mar 2021 18:34:37 +0000 (UTC) Received: from malabar-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: bbhatt) by smtp.codeaurora.org (Postfix) with ESMTPSA id 5846FC433CA; Wed, 31 Mar 2021 18:34:36 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 5846FC433CA Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=bbhatt@codeaurora.org From: Bhaumik Bhatt To: manivannan.sadhasivam@linaro.org Cc: linux-arm-msm@vger.kernel.org, hemantk@codeaurora.org, jhugo@codeaurora.org, linux-kernel@vger.kernel.org, carl.yin@quectel.com, naveen.kumar@quectel.com, loic.poulain@linaro.org, Bhaumik Bhatt Subject: [PATCH v6 2/2] bus: mhi: core: Move to polling method to wait for MHI ready Date: Wed, 31 Mar 2021 11:34:25 -0700 Message-Id: <1617215665-19593-3-git-send-email-bbhatt@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1617215665-19593-1-git-send-email-bbhatt@codeaurora.org> References: <1617215665-19593-1-git-send-email-bbhatt@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org In certain devices, it is likely that there is no incoming MHI interrupt for a transition to MHI READY state. One such example is the move from Pass Through to an SBL or AMSS execution environment. In order to facilitate faster bootup times as there is no need to wait until timeout_ms completes, MHI host can poll every 25 milliseconds to check if device has entered MHI READY until a maximum timeout of twice the timeout_ms is reached. Signed-off-by: Bhaumik Bhatt Reviewed-by: Loic Poulain --- drivers/bus/mhi/core/pm.c | 34 ++++++++++++++++------------------ 1 file changed, 16 insertions(+), 18 deletions(-) diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c index b6920a5..e4aff77 100644 --- a/drivers/bus/mhi/core/pm.c +++ b/drivers/bus/mhi/core/pm.c @@ -153,35 +153,33 @@ static void mhi_toggle_dev_wake(struct mhi_controller *mhi_cntrl) /* Handle device ready state transition */ int mhi_ready_state_transition(struct mhi_controller *mhi_cntrl) { - void __iomem *base = mhi_cntrl->regs; struct mhi_event *mhi_event; enum mhi_pm_state cur_state; struct device *dev = &mhi_cntrl->mhi_dev->dev; - u32 reset = 1, ready = 0; + u32 interval_us = 25000; /* poll register field every 25 milliseconds */ int ret, i; - /* Wait for RESET to be cleared and READY bit to be set by the device */ - wait_event_timeout(mhi_cntrl->state_event, - MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state) || - mhi_read_reg_field(mhi_cntrl, base, MHICTRL, - MHICTRL_RESET_MASK, - MHICTRL_RESET_SHIFT, &reset) || - mhi_read_reg_field(mhi_cntrl, base, MHISTATUS, - MHISTATUS_READY_MASK, - MHISTATUS_READY_SHIFT, &ready) || - (!reset && ready), - msecs_to_jiffies(mhi_cntrl->timeout_ms)); - /* Check if device entered error state */ if (MHI_PM_IN_FATAL_STATE(mhi_cntrl->pm_state)) { dev_err(dev, "Device link is not accessible\n"); return -EIO; } - /* Timeout if device did not transition to ready state */ - if (reset || !ready) { - dev_err(dev, "Device Ready timeout\n"); - return -ETIMEDOUT; + /* Wait for RESET to be cleared and READY bit to be set by the device */ + ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHICTRL, + MHICTRL_RESET_MASK, MHICTRL_RESET_SHIFT, 0, + interval_us); + if (ret) { + dev_err(dev, "Device failed to clear MHI Reset\n"); + return ret; + } + + ret = mhi_poll_reg_field(mhi_cntrl, mhi_cntrl->regs, MHISTATUS, + MHISTATUS_READY_MASK, MHISTATUS_READY_SHIFT, 1, + interval_us); + if (ret) { + dev_err(dev, "Device failed to enter MHI Ready\n"); + return ret; } dev_dbg(dev, "Device in READY State\n"); -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project