From patchwork Wed Mar 10 23:31:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaumik Bhatt X-Patchwork-Id: 12129747 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,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 952E4C433E0 for ; Wed, 10 Mar 2021 23:32:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 61EA664FCA for ; Wed, 10 Mar 2021 23:32:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233830AbhCJXbf (ORCPT ); Wed, 10 Mar 2021 18:31:35 -0500 Received: from m42-2.mailgun.net ([69.72.42.2]:33254 "EHLO m42-2.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233873AbhCJXbc (ORCPT ); Wed, 10 Mar 2021 18:31:32 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1615419092; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=8QPQ7A4y9jySrbcGeh1018gAyYPHik4GWI6KwBvFwWU=; b=QbJGJd8pjw1lVyHA8OnnDbCY5Y6ljAROPfUZVtMlOBsKAAPXDddD7X8Sx0ox5zmd1AqfQyKK bAp/RbYbEGKAuU6h4uVouxGI/QlF2HvR3w7ArE5eCxKz9mI1A9vBD9Z5oFckjx1RZwu0PGbx 09vZtEZ72B160ncrkB6xxjPLyKI= X-Mailgun-Sending-Ip: 69.72.42.2 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-n01.prod.us-west-2.postgun.com with SMTP id 604956d3fa6ebd85e8c11c90 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 10 Mar 2021 23:31:31 GMT Sender: bbhatt=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id AABAEC43464; Wed, 10 Mar 2021 23:31:31 +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 C6FB9C43463; Wed, 10 Mar 2021 23:31:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org C6FB9C43463 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 v4 2/3] bus: mhi: core: Move to polling method to wait for MHI ready Date: Wed, 10 Mar 2021 15:31:19 -0800 Message-Id: <1615419080-26540-3-git-send-email-bbhatt@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1615419080-26540-1-git-send-email-bbhatt@codeaurora.org> References: <1615419080-26540-1-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 --- drivers/bus/mhi/core/pm.c | 32 +++++++++++++++----------------- 1 file changed, 15 insertions(+), 17 deletions(-) diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c index 681960c..dcc7fe0 100644 --- a/drivers/bus/mhi/core/pm.c +++ b/drivers/bus/mhi/core/pm.c @@ -153,34 +153,32 @@ 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"); + /* 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 -ETIMEDOUT; + } + + 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 -ETIMEDOUT; }