From patchwork Fri Jan 8 20:54:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaumik Bhatt X-Patchwork-Id: 12007579 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 C81A5C432C3 for ; Fri, 8 Jan 2021 20:56:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9C27323B1F for ; Fri, 8 Jan 2021 20:56:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729463AbhAHU4L (ORCPT ); Fri, 8 Jan 2021 15:56:11 -0500 Received: from m43-15.mailgun.net ([69.72.43.15]:58946 "EHLO m43-15.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729451AbhAHU4K (ORCPT ); Fri, 8 Jan 2021 15:56:10 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1610139345; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=d7jmQdZBukT+MtEgjaRt+mGsrNo6F0Q786uu12YQiik=; b=bOZvl/jRTyLUNSf0EB4/o1Zzq7IvLKBCIncBl4tI8DYqF9SBMjWlLwGvmGQj6N6ERFuWlvYm fWwM7lEbe9k+v8qjQQt3ogZR5LUF7j4qmhJcKjrHZyGfXFSJL4LUMUsLS6XXtc5zv9wwdYct qGAerEPGjZfZ9bOS70COxLj/b9g= X-Mailgun-Sending-Ip: 69.72.43.15 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-east-1.postgun.com with SMTP id 5ff8c6abc88af0610747f941 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 08 Jan 2021 20:55:07 GMT Sender: bbhatt=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 8D1DFC433CA; Fri, 8 Jan 2021 20:55:06 +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 8FC9BC433ED; Fri, 8 Jan 2021 20:55:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 8FC9BC433ED 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 v5 3/9] bus: mhi: core: Improvements to the channel handling state machine Date: Fri, 8 Jan 2021 12:54:51 -0800 Message-Id: <1610139297-36435-4-git-send-email-bbhatt@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1610139297-36435-1-git-send-email-bbhatt@codeaurora.org> References: <1610139297-36435-1-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. 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 | 166 +++++++++++++++++++++++----------------- 3 files changed, 114 insertions(+), 70 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 c22d7df..081fdf0 100644 --- a/drivers/bus/mhi/core/main.c +++ b/drivers/bus/mhi/core/main.c @@ -1250,56 +1250,118 @@ 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 = -EIO; + + dev_dbg(dev, "Updating channel %s(%d) state to: %s\n", mhi_chan->name, + 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); + goto exit_invalid_state; + } + 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) + goto exit_invalid_state; - /* 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) + goto exit_invalid_state; + + cmd = MHI_CMD_START_CHAN; + break; + default: + goto exit_invalid_state; } - 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, "Failed to send %s(%d) %s command\n", + mhi_chan->name, mhi_chan->chan, + TO_CH_STATE_TYPE_STR(to_state)); + goto exit_command_failure; } - 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, "Failed to receive %s(%d) %s command completion\n", + mhi_chan->name, mhi_chan->chan, + TO_CH_STATE_TYPE_STR(to_state)); + ret = -EIO; + goto exit_command_failure; + } - 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, "Channel %s(%d) state change to %s successful\n", + mhi_chan->name, mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); + +exit_command_failure: 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; + +exit_invalid_state: + dev_err(dev, "Channel %s(%d) update to %s not allowed\n", + mhi_chan->name, mhi_chan->chan, TO_CH_STATE_TYPE_STR(to_state)); + + return -EINVAL; +} + +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; + + /* no more processing events for this channel */ + mutex_lock(&mhi_chan->mutex); + + ret = mhi_update_channel_state(mhi_cntrl, mhi_chan, + MHI_CH_STATE_TYPE_RESET); + if (ret) + dev_err(dev, "Failed to reset channel, still resetting\n"); -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, "chan:%d successfully reset\n", mhi_chan->chan); + mutex_unlock(&mhi_chan->mutex); } @@ -1309,8 +1371,6 @@ 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", @@ -1321,14 +1381,6 @@ 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); @@ -1336,34 +1388,11 @@ 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, @@ -1401,9 +1430,6 @@ 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: