From patchwork Thu Apr 1 21:16:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaumik Bhatt X-Patchwork-Id: 12179567 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 005FDC43470 for ; Thu, 1 Apr 2021 21:16:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D971E610F8 for ; Thu, 1 Apr 2021 21:16:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234845AbhDAVQx (ORCPT ); Thu, 1 Apr 2021 17:16:53 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:33124 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234745AbhDAVQx (ORCPT ); Thu, 1 Apr 2021 17:16:53 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1617311813; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=zeN5/NBpLOxvJXilPKSqJ4VlGe1u0vXSEmecnzjAsuw=; b=XhdKbVjVhO0xCiqZghyTLnBoQCCiGT5airxa7+azyW7SWXTpFFWDgluVaoF7mDjJfxEDl3YX gV2+xmmaQTj2pMcQBETN7FJMCpV9sUu/Afpzj1pVZ+jHuiLE3QT8xnx7U8XPUspdobpzgtf3 hz6laEP8o6EUfl4h1CDdmwNip0c= 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-n04.prod.us-west-2.postgun.com with SMTP id 6066382c9a9ff96d95df4d7b (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Thu, 01 Apr 2021 21:16:28 GMT Sender: bbhatt=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id BBB93C433CA; Thu, 1 Apr 2021 21:16:27 +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 967A4C43462; Thu, 1 Apr 2021 21:16:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 967A4C43462 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 v8 3/9] bus: mhi: core: Improvements to the channel handling state machine Date: Thu, 1 Apr 2021 14:16:12 -0700 Message-Id: <1617311778-1254-4-git-send-email-bbhatt@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1617311778-1254-1-git-send-email-bbhatt@codeaurora.org> References: <1617311778-1254-1-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 a validation process to ensure that the state machine is not violated in any way and adheres to the MHI specification. Using this common function allows MHI to eliminate some unnecessary debug messages and code duplication. Signed-off-by: Bhaumik Bhatt Reviewed-by: Manivannan Sadhasivam Reviewed-by: Jeffrey Hugo --- drivers/bus/mhi/core/init.c | 6 ++ drivers/bus/mhi/core/internal.h | 12 ++++ drivers/bus/mhi/core/main.c | 151 ++++++++++++++++++++++------------------ 3 files changed, 100 insertions(+), 69 deletions(-) diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c index f8ba954..9c2ed92 100644 --- a/drivers/bus/mhi/core/init.c +++ b/drivers/bus/mhi/core/init.c @@ -56,6 +56,12 @@ const char * const mhi_state_str[MHI_STATE_MAX] = { [MHI_STATE_SYS_ERR] = "SYS ERROR", }; +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] = "POWER ON RESET", diff --git a/drivers/bus/mhi/core/internal.h b/drivers/bus/mhi/core/internal.h index e690f15..5b9ea66 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 8c510f1..710ca0f 100644 --- a/drivers/bus/mhi/core/main.c +++ b/drivers/bus/mhi/core/main.c @@ -1234,56 +1234,105 @@ 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; + enum mhi_cmd_type cmd = MHI_CMD_NOP; + int ret; - dev_dbg(dev, "Entered: unprepare channel:%d\n", mhi_chan->chan); - - /* 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) { + 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); - mutex_unlock(&mhi_chan->mutex); - return; - } - mhi_chan->ch_state = MHI_CH_STATE_DISABLED; - write_unlock_irq(&mhi_chan->lock); + cmd = MHI_CMD_RESET_CHAN; + break; + case MHI_CH_STATE_TYPE_STOP: + if (mhi_chan->ch_state != MHI_CH_STATE_ENABLED) + return -EINVAL; - 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; + 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_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_RESET_CHAN); - if (ret) - goto error_invalid_state; - /* even if it fails we will still reset */ + reinit_completion(&mhi_chan->completion); + 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)); + return ret; + } + ret = wait_for_completion_timeout(&mhi_chan->completion, - msecs_to_jiffies(mhi_cntrl->timeout_ms)); - if (!ret || mhi_chan->ccs != MHI_EV_CC_SUCCESS) + 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"); + "%d: Failed to receive %s channel command completion\n", + mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); + return -EIO; + } + + 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)); + + return 0; +} + +static void __mhi_unprepare_channel(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan) +{ + int ret; + struct device *dev = &mhi_cntrl->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); } @@ -1293,8 +1342,6 @@ int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, int ret = 0; struct device *dev = &mhi_cntrl->mhi_dev->dev; - dev_dbg(dev, "Preparing channel: %d\n", mhi_chan->chan); - if (!(BIT(mhi_cntrl->ee) & mhi_chan->ee_mask)) { dev_err(dev, "Current EE: %s Required EE Mask: 0x%x for chan: %s\n", @@ -1305,14 +1352,6 @@ int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, 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); @@ -1320,34 +1359,11 @@ 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, @@ -1385,9 +1401,6 @@ 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: