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=-17.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 50F91C433B4 for ; Wed, 7 Apr 2021 06:26:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0E4AC613C0 for ; Wed, 7 Apr 2021 06:26:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233863AbhDGG0n (ORCPT ); Wed, 7 Apr 2021 02:26:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230426AbhDGG0m (ORCPT ); Wed, 7 Apr 2021 02:26:42 -0400 Received: from mail-pl1-x635.google.com (mail-pl1-x635.google.com [IPv6:2607:f8b0:4864:20::635]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 57732C06174A for ; Tue, 6 Apr 2021 23:26:33 -0700 (PDT) Received: by mail-pl1-x635.google.com with SMTP id a6so5483631pls.1 for ; Tue, 06 Apr 2021 23:26:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=Nv+030+K+5MMv235heiMJ5vuiaCK99dbHL27acpLMHc=; b=qFZMjlysbpozfuJdNAjyNixJqKWCdlp/3WDF/JGEk9CTodY9y6maOmpsY+kdOl06ev J88ZQ8TNbQ8lwWfDTq34BDt8XjrCNeywg+r899IP9pYeWUodIH4uLu5czqk6JyRdws5O ieDwOjisAAJ76T/gla0pyFO0t3YouCqyQYuxLnCJCu2AnNKQKA5rp0T9i0T8bd4h+rHz m022UWyQ5l5Ug76xealLqxUKSFOBe3m7Tr/X3+bsYCsMm5xwlKxxyh8ySi2wiHxkVP/v +LQwKiGNlMUPxLKdFFicVERxvXBGr96wZao9iIa6QyKZqawhOmQ6nExwdC884qvO6KQ0 n3Cw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=Nv+030+K+5MMv235heiMJ5vuiaCK99dbHL27acpLMHc=; b=jQoQtRp32mJg6RUyqOdKpAfI/oR/xwN9Z0TmF+/YSK6gpebE5+XN3ujrur941K35t2 JF2O+yuieqRJlm+LEX6ORNcxurLFbAbRJ7yKnA+YYPq+l8ROmJBjmHW7UM18EfgdDV2E PycAF/P/ZeZO70BoDHb8b94Q5tlIX112N5/Rbl9HKFTfl5k4bzDS4FRBlD6LFnv/OCTH QKUK0lf3TFqJ8+6qH01x0LzGrlBfXmE3CLha4kHv09WOY7aDLLcJdxLwcRz4VdXdj8HL IkAL4wR8kbC8jSxSRxwwYBbwFZciyR45l5TLwawHXC/FZs7J1+Lw5E+OYN1enCfY98AT 4gEw== X-Gm-Message-State: AOAM531vVkgTnUfBnxhaOEBRixKj2dyaFzV1lllsJzvMM5jOy+axL6r6 O5n/4AT2bx76o78BJ+mf5pmsK/AdgZlR X-Google-Smtp-Source: ABdhPJw6yOW1YjqXTz+FAgI1V1Y8knt7AldjaYkyJ+J41U4Eks+B+EZCYxoOvVGOssDCVQlC7WeNrw== X-Received: by 2002:a17:90b:3114:: with SMTP id gc20mr1865620pjb.123.1617776792533; Tue, 06 Apr 2021 23:26:32 -0700 (PDT) Received: from work ([103.77.37.180]) by smtp.gmail.com with ESMTPSA id r11sm4046536pjp.46.2021.04.06.23.26.29 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Tue, 06 Apr 2021 23:26:31 -0700 (PDT) Date: Wed, 7 Apr 2021 11:56:28 +0530 From: Manivannan Sadhasivam To: Bhaumik Bhatt 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 Subject: Re: [PATCH v8 3/9] bus: mhi: core: Improvements to the channel handling state machine Message-ID: <20210407062628.GE8675@work> References: <1617311778-1254-1-git-send-email-bbhatt@codeaurora.org> <1617311778-1254-4-git-send-email-bbhatt@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1617311778-1254-4-git-send-email-bbhatt@codeaurora.org> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Thu, Apr 01, 2021 at 02:16:12PM -0700, Bhaumik Bhatt wrote: > 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 Thanks, Mani > --- > 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: > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project >