From patchwork Thu Feb 4 20:28:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaumik Bhatt X-Patchwork-Id: 12068645 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=-16.7 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 36268C433E0 for ; Thu, 4 Feb 2021 20:30:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EEA4664E35 for ; Thu, 4 Feb 2021 20:30:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240189AbhBDUaf (ORCPT ); Thu, 4 Feb 2021 15:30:35 -0500 Received: from mail29.static.mailgun.info ([104.130.122.29]:12537 "EHLO mail29.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240152AbhBDU3O (ORCPT ); Thu, 4 Feb 2021 15:29:14 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1612470536; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=B7Wu4TucXAPkBHPCSGCPoSmKhx1V1uq8lHeYCM6riAE=; b=UV4NpEcUf116sbPeuwSZKD3ZMdjlejzP5gHgdn0bn2f6C3hG/H5Vt4s2RKdsSa/LvsLP6OZQ DeWMgnWw3kN8LvDKFxipDDpORl+Ww3tQ6lzHfQfGuZ0YzrvyD1JJaDBytAWTU4CDKKCGV4QZ 5YyH7tZJaawyWXQch9yz8sMaa/A= X-Mailgun-Sending-Ip: 104.130.122.29 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-n02.prod.us-west-2.postgun.com with SMTP id 601c58dff112b7872cc14d59 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Thu, 04 Feb 2021 20:28:15 GMT Sender: bbhatt=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id B721BC433CA; Thu, 4 Feb 2021 20:28:15 +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 61692C43462; Thu, 4 Feb 2021 20:28:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 61692C43462 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, loic.poulain@linaro.org, Bhaumik Bhatt Subject: [PATCH v6 3/8] bus: mhi: core: Improvements to the channel handling state machine Date: Thu, 4 Feb 2021 12:28:01 -0800 Message-Id: <1612470486-10440-4-git-send-email-bbhatt@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1612470486-10440-1-git-send-email-bbhatt@codeaurora.org> References: <1612470486-10440-1-git-send-email-bbhatt@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Improve the channel handling state machine such that all commands go through a common function and validation process to ensure that the state machine is not violated in any way and adheres to the MHI specification. Assert device wake before sending the channel update commands instead of a wake toggle to ensure we fail if device is in a bad state. Also update print messages to use client device to accurately represent the channel being updated. Signed-off-by: Bhaumik Bhatt Reviewed-by: Hemant Kumar --- drivers/bus/mhi/core/init.c | 6 ++ drivers/bus/mhi/core/internal.h | 12 +++ drivers/bus/mhi/core/main.c | 172 ++++++++++++++++++++++------------------ 3 files changed, 114 insertions(+), 76 deletions(-) diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c index 03c5786..482b365 100644 --- a/drivers/bus/mhi/core/init.c +++ b/drivers/bus/mhi/core/init.c @@ -54,6 +54,12 @@ const char * const mhi_state_str[MHI_STATE_MAX] = { [MHI_STATE_SYS_ERR] = "SYS_ERR", }; +const char * const mhi_ch_state_type_str[MHI_CH_STATE_TYPE_MAX] = { + [MHI_CH_STATE_TYPE_RESET] = "RESET", + [MHI_CH_STATE_TYPE_STOP] = "STOP", + [MHI_CH_STATE_TYPE_START] = "START", +}; + static const char * const mhi_pm_state_str[] = { [MHI_PM_STATE_DISABLE] = "DISABLE", [MHI_PM_STATE_POR] = "POR", diff --git a/drivers/bus/mhi/core/internal.h b/drivers/bus/mhi/core/internal.h index 6f80ec3..7e3aac1 100644 --- a/drivers/bus/mhi/core/internal.h +++ b/drivers/bus/mhi/core/internal.h @@ -369,6 +369,18 @@ enum mhi_ch_state { MHI_CH_STATE_ERROR = 0x5, }; +enum mhi_ch_state_type { + MHI_CH_STATE_TYPE_RESET, + MHI_CH_STATE_TYPE_STOP, + MHI_CH_STATE_TYPE_START, + MHI_CH_STATE_TYPE_MAX, +}; + +extern const char * const mhi_ch_state_type_str[MHI_CH_STATE_TYPE_MAX]; +#define TO_CH_STATE_TYPE_STR(state) (((state) >= MHI_CH_STATE_TYPE_MAX) ? \ + "INVALID_STATE" : \ + mhi_ch_state_type_str[(state)]) + #define MHI_INVALID_BRSTMODE(mode) (mode != MHI_DB_BRST_DISABLE && \ mode != MHI_DB_BRST_ENABLE) diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c index d068188..2f6fdb2 100644 --- a/drivers/bus/mhi/core/main.c +++ b/drivers/bus/mhi/core/main.c @@ -1188,56 +1188,114 @@ int mhi_send_cmd(struct mhi_controller *mhi_cntrl, return 0; } -static void __mhi_unprepare_channel(struct mhi_controller *mhi_cntrl, - struct mhi_chan *mhi_chan) +static int mhi_update_channel_state(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan, + enum mhi_ch_state_type to_state) { - int ret; - struct device *dev = &mhi_cntrl->mhi_dev->dev; + struct device *dev = &mhi_chan->mhi_dev->dev; + enum mhi_cmd_type cmd = MHI_CMD_NOP; + int ret = -EIO; + + dev_dbg(dev, "%d: Updating channel state to: %s\n", mhi_chan->chan, + TO_CH_STATE_TYPE_STR(to_state)); + + switch (to_state) { + case MHI_CH_STATE_TYPE_RESET: + write_lock_irq(&mhi_chan->lock); + if (mhi_chan->ch_state != MHI_CH_STATE_STOP && + mhi_chan->ch_state != MHI_CH_STATE_ENABLED && + mhi_chan->ch_state != MHI_CH_STATE_SUSPENDED) { + write_unlock_irq(&mhi_chan->lock); + return -EINVAL; + } + mhi_chan->ch_state = MHI_CH_STATE_DISABLED; + write_unlock_irq(&mhi_chan->lock); - dev_dbg(dev, "Entered: unprepare channel:%d\n", mhi_chan->chan); + cmd = MHI_CMD_RESET_CHAN; + break; + case MHI_CH_STATE_TYPE_STOP: + if (mhi_chan->ch_state != MHI_CH_STATE_ENABLED) + return -EINVAL; - /* no more processing events for this channel */ - mutex_lock(&mhi_chan->mutex); - write_lock_irq(&mhi_chan->lock); - if (mhi_chan->ch_state != MHI_CH_STATE_ENABLED && - mhi_chan->ch_state != MHI_CH_STATE_SUSPENDED) { - write_unlock_irq(&mhi_chan->lock); - mutex_unlock(&mhi_chan->mutex); - return; + cmd = MHI_CMD_STOP_CHAN; + break; + case MHI_CH_STATE_TYPE_START: + if (mhi_chan->ch_state != MHI_CH_STATE_STOP && + mhi_chan->ch_state != MHI_CH_STATE_DISABLED) + return -EINVAL; + + cmd = MHI_CMD_START_CHAN; + break; + default: + dev_err(dev, "%d: Channel state update to %s not allowed\n", + mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); + return -EINVAL; } - mhi_chan->ch_state = MHI_CH_STATE_DISABLED; - write_unlock_irq(&mhi_chan->lock); + /* bring host and device out of suspended states */ + ret = mhi_device_get_sync(mhi_cntrl->mhi_dev); + if (ret) + return ret; + mhi_cntrl->runtime_get(mhi_cntrl); reinit_completion(&mhi_chan->completion); - read_lock_bh(&mhi_cntrl->pm_lock); - if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) { - read_unlock_bh(&mhi_cntrl->pm_lock); - goto error_invalid_state; + ret = mhi_send_cmd(mhi_cntrl, mhi_chan, cmd); + if (ret) { + dev_err(dev, "%d: Failed to send %s channel command\n", + mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); + goto exit_channel_update; } - mhi_cntrl->wake_toggle(mhi_cntrl); - read_unlock_bh(&mhi_cntrl->pm_lock); + ret = wait_for_completion_timeout(&mhi_chan->completion, + msecs_to_jiffies(mhi_cntrl->timeout_ms)); + if (!ret || mhi_chan->ccs != MHI_EV_CC_SUCCESS) { + dev_err(dev, + "%d: Failed to receive %s channel command completion\n", + mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); + ret = -EIO; + goto exit_channel_update; + } - mhi_cntrl->runtime_get(mhi_cntrl); + ret = 0; + + if (to_state != MHI_CH_STATE_TYPE_RESET) { + write_lock_irq(&mhi_chan->lock); + mhi_chan->ch_state = (to_state == MHI_CH_STATE_TYPE_START) ? + MHI_CH_STATE_ENABLED : MHI_CH_STATE_STOP; + write_unlock_irq(&mhi_chan->lock); + } + + dev_dbg(dev, "%d: Channel state change to %s successful\n", + mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); + +exit_channel_update: mhi_cntrl->runtime_put(mhi_cntrl); - ret = mhi_send_cmd(mhi_cntrl, mhi_chan, MHI_CMD_RESET_CHAN); - if (ret) - goto error_invalid_state; + mhi_device_put(mhi_cntrl->mhi_dev); - /* even if it fails we will still reset */ - ret = wait_for_completion_timeout(&mhi_chan->completion, - msecs_to_jiffies(mhi_cntrl->timeout_ms)); - if (!ret || mhi_chan->ccs != MHI_EV_CC_SUCCESS) - dev_err(dev, - "Failed to receive cmd completion, still resetting\n"); + return ret; +} + +static void __mhi_unprepare_channel(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan) +{ + int ret; + struct device *dev = &mhi_chan->mhi_dev->dev; + + mutex_lock(&mhi_chan->mutex); + + /* no more processing events for this channel */ + ret = mhi_update_channel_state(mhi_cntrl, mhi_chan, + MHI_CH_STATE_TYPE_RESET); + if (ret) + dev_err(dev, "%d: Failed to reset channel, still resetting\n", + mhi_chan->chan); -error_invalid_state: if (!mhi_chan->offload_ch) { mhi_reset_chan(mhi_cntrl, mhi_chan); mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan); } - dev_dbg(dev, "chan:%d successfully resetted\n", mhi_chan->chan); + dev_dbg(dev, "%d: successfully reset\n", mhi_chan->chan); + mutex_unlock(&mhi_chan->mutex); } @@ -1245,28 +1303,16 @@ int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan) { int ret = 0; - struct device *dev = &mhi_cntrl->mhi_dev->dev; - - dev_dbg(dev, "Preparing channel: %d\n", mhi_chan->chan); + struct device *dev = &mhi_chan->mhi_dev->dev; if (!(BIT(mhi_cntrl->ee) & mhi_chan->ee_mask)) { - dev_err(dev, - "Current EE: %s Required EE Mask: 0x%x for chan: %s\n", - TO_MHI_EXEC_STR(mhi_cntrl->ee), mhi_chan->ee_mask, - mhi_chan->name); + dev_err(dev, "Current EE: %s Required EE Mask: 0x%x\n", + TO_MHI_EXEC_STR(mhi_cntrl->ee), mhi_chan->ee_mask); return -ENOTCONN; } mutex_lock(&mhi_chan->mutex); - /* If channel is not in disable state, do not allow it to start */ - if (mhi_chan->ch_state != MHI_CH_STATE_DISABLED) { - ret = -EIO; - dev_dbg(dev, "channel: %d is not in disabled state\n", - mhi_chan->chan); - goto error_init_chan; - } - /* Check of client manages channel context for offload channels */ if (!mhi_chan->offload_ch) { ret = mhi_init_chan_ctxt(mhi_cntrl, mhi_chan); @@ -1274,34 +1320,11 @@ int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, goto error_init_chan; } - reinit_completion(&mhi_chan->completion); - read_lock_bh(&mhi_cntrl->pm_lock); - if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) { - read_unlock_bh(&mhi_cntrl->pm_lock); - ret = -EIO; - goto error_pm_state; - } - - mhi_cntrl->wake_toggle(mhi_cntrl); - read_unlock_bh(&mhi_cntrl->pm_lock); - mhi_cntrl->runtime_get(mhi_cntrl); - mhi_cntrl->runtime_put(mhi_cntrl); - - ret = mhi_send_cmd(mhi_cntrl, mhi_chan, MHI_CMD_START_CHAN); + ret = mhi_update_channel_state(mhi_cntrl, mhi_chan, + MHI_CH_STATE_TYPE_START); if (ret) goto error_pm_state; - ret = wait_for_completion_timeout(&mhi_chan->completion, - msecs_to_jiffies(mhi_cntrl->timeout_ms)); - if (!ret || mhi_chan->ccs != MHI_EV_CC_SUCCESS) { - ret = -EIO; - goto error_pm_state; - } - - write_lock_irq(&mhi_chan->lock); - mhi_chan->ch_state = MHI_CH_STATE_ENABLED; - write_unlock_irq(&mhi_chan->lock); - /* Pre-allocate buffer for xfer ring */ if (mhi_chan->pre_alloc) { int nr_el = get_nr_avail_ring_elements(mhi_cntrl, @@ -1339,9 +1362,6 @@ int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, mutex_unlock(&mhi_chan->mutex); - dev_dbg(dev, "Chan: %d successfully moved to start state\n", - mhi_chan->chan); - return 0; error_pm_state: