From patchwork Mon Nov 9 20:47:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaumik Bhatt X-Patchwork-Id: 11892469 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 521886A2 for ; Mon, 9 Nov 2020 20:48:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E10F20731 for ; Mon, 9 Nov 2020 20:48:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="OPmuPuGA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730858AbgKIUsG (ORCPT ); Mon, 9 Nov 2020 15:48:06 -0500 Received: from m42-4.mailgun.net ([69.72.42.4]:51128 "EHLO m42-4.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730825AbgKIUrr (ORCPT ); Mon, 9 Nov 2020 15:47:47 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1604954867; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=6XTYQyO2klmQXkKHAEjhN4DTjPEKBBsIlMgadavihz4=; b=OPmuPuGAWUEK9LGY9LRXva+XK7r2SVWQ5wcR7KH94tG9mJvMThPD/2BFqgnSDeKpBxYzUSi+ 12+zawowb4tOfQRzxk6HEjCWrFtegoUELw1fHOPH1Ct4wFKQBrGhyhweHhVhIHNRdM3WZIHT JEerbzBrzJ3gRXa02onjh3ZFYLM= X-Mailgun-Sending-Ip: 69.72.42.4 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-n07.prod.us-east-1.postgun.com with SMTP id 5fa9aaf28723a97b70f1602d (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Mon, 09 Nov 2020 20:47:46 GMT Sender: bbhatt=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id D97A8C433CB; Mon, 9 Nov 2020 20:47:45 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=ALL_TRUSTED,BAYES_00,SPF_FAIL, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 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 7D47CC433CB; Mon, 9 Nov 2020 20:47:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 7D47CC433CB 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, Bhaumik Bhatt Subject: [PATCH v4 10/12] bus: mhi: core: Separate system error and power down handling Date: Mon, 9 Nov 2020 12:47:29 -0800 Message-Id: <1604954851-23396-11-git-send-email-bbhatt@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1604954851-23396-1-git-send-email-bbhatt@codeaurora.org> References: <1604954851-23396-1-git-send-email-bbhatt@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Currently, there exist a set of if...else statements in the mhi_pm_disable_transition() function which make handling system error and disable transitions differently complex. To make that cleaner and facilitate differences in behavior, separate these two transitions for MHI host. Signed-off-by: Bhaumik Bhatt Reviewed-by: Manivannan Sadhasivam --- drivers/bus/mhi/core/pm.c | 159 +++++++++++++++++++++++++++++++++++++++------- 1 file changed, 137 insertions(+), 22 deletions(-) diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c index 1d04e401..347ae7d 100644 --- a/drivers/bus/mhi/core/pm.c +++ b/drivers/bus/mhi/core/pm.c @@ -444,7 +444,7 @@ static int mhi_pm_mission_mode_transition(struct mhi_controller *mhi_cntrl) return ret; } -/* Handle SYS_ERR and Shutdown transitions */ +/* Handle shutdown transitions */ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl, enum mhi_pm_state transition_state) { @@ -460,10 +460,6 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl, to_mhi_pm_state_str(mhi_cntrl->pm_state), to_mhi_pm_state_str(transition_state)); - /* We must notify MHI control driver so it can clean up first */ - if (transition_state == MHI_PM_SYS_ERR_PROCESS) - mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_SYS_ERROR); - mutex_lock(&mhi_cntrl->pm_mutex); write_lock_irq(&mhi_cntrl->pm_lock); prev_state = mhi_cntrl->pm_state; @@ -502,11 +498,8 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl, MHICTRL_RESET_SHIFT, &in_reset) || !in_reset, timeout); - if ((!ret || in_reset) && cur_state == MHI_PM_SYS_ERR_PROCESS) { + if (!ret || in_reset) dev_err(dev, "Device failed to exit MHI Reset state\n"); - mutex_unlock(&mhi_cntrl->pm_mutex); - return; - } /* * Device will clear BHI_INTVEC as a part of RESET processing, @@ -566,19 +559,142 @@ static void mhi_pm_disable_transition(struct mhi_controller *mhi_cntrl, er_ctxt->wp = er_ctxt->rbase; } - if (cur_state == MHI_PM_SYS_ERR_PROCESS) { - mhi_ready_state_transition(mhi_cntrl); - } else { - /* Move to disable state */ - write_lock_irq(&mhi_cntrl->pm_lock); - cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_DISABLE); - write_unlock_irq(&mhi_cntrl->pm_lock); - if (unlikely(cur_state != MHI_PM_DISABLE)) - dev_err(dev, "Error moving from PM state: %s to: %s\n", - to_mhi_pm_state_str(cur_state), - to_mhi_pm_state_str(MHI_PM_DISABLE)); + /* Move to disable state */ + write_lock_irq(&mhi_cntrl->pm_lock); + cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_DISABLE); + write_unlock_irq(&mhi_cntrl->pm_lock); + if (unlikely(cur_state != MHI_PM_DISABLE)) + dev_err(dev, "Error moving from PM state: %s to: %s\n", + to_mhi_pm_state_str(cur_state), + to_mhi_pm_state_str(MHI_PM_DISABLE)); + + dev_dbg(dev, "Exiting with PM state: %s, MHI state: %s\n", + to_mhi_pm_state_str(mhi_cntrl->pm_state), + TO_MHI_STATE_STR(mhi_cntrl->dev_state)); + + mutex_unlock(&mhi_cntrl->pm_mutex); +} + +/* Handle system error transitions */ +static void mhi_pm_sys_error_transition(struct mhi_controller *mhi_cntrl) +{ + enum mhi_pm_state cur_state, prev_state; + struct mhi_event *mhi_event; + struct mhi_cmd_ctxt *cmd_ctxt; + struct mhi_cmd *mhi_cmd; + struct mhi_event_ctxt *er_ctxt; + struct device *dev = &mhi_cntrl->mhi_dev->dev; + int ret, i; + + dev_dbg(dev, "Transitioning from PM state: %s to: %s\n", + to_mhi_pm_state_str(mhi_cntrl->pm_state), + to_mhi_pm_state_str(MHI_PM_SYS_ERR_PROCESS)); + + /* We must notify MHI control driver so it can clean up first */ + mhi_cntrl->status_cb(mhi_cntrl, MHI_CB_SYS_ERROR); + + mutex_lock(&mhi_cntrl->pm_mutex); + write_lock_irq(&mhi_cntrl->pm_lock); + prev_state = mhi_cntrl->pm_state; + cur_state = mhi_tryset_pm_state(mhi_cntrl, MHI_PM_SYS_ERR_PROCESS); + write_unlock_irq(&mhi_cntrl->pm_lock); + + if (cur_state != MHI_PM_SYS_ERR_PROCESS) { + dev_err(dev, "Failed to transition from PM state: %s to: %s\n", + to_mhi_pm_state_str(cur_state), + to_mhi_pm_state_str(MHI_PM_SYS_ERR_PROCESS)); + goto exit_sys_error_transition; + } + + mhi_cntrl->ee = MHI_EE_DISABLE_TRANSITION; + mhi_cntrl->dev_state = MHI_STATE_RESET; + + /* Wake up threads waiting for state transition */ + wake_up_all(&mhi_cntrl->state_event); + + /* Trigger MHI RESET so that the device will not access host memory */ + if (MHI_REG_ACCESS_VALID(prev_state)) { + u32 in_reset = -1; + unsigned long timeout = msecs_to_jiffies(mhi_cntrl->timeout_ms); + + dev_dbg(dev, "Triggering MHI Reset in device\n"); + mhi_set_mhi_state(mhi_cntrl, MHI_STATE_RESET); + + /* Wait for the reset bit to be cleared by the device */ + ret = wait_event_timeout(mhi_cntrl->state_event, + mhi_read_reg_field(mhi_cntrl, + mhi_cntrl->regs, + MHICTRL, + MHICTRL_RESET_MASK, + MHICTRL_RESET_SHIFT, + &in_reset) || + !in_reset, timeout); + if (!ret || in_reset) { + dev_err(dev, "Device failed to exit MHI Reset state\n"); + goto exit_sys_error_transition; + } + + /* + * Device will clear BHI_INTVEC as a part of RESET processing, + * hence re-program it + */ + mhi_write_reg(mhi_cntrl, mhi_cntrl->bhi, BHI_INTVEC, 0); + } + + dev_dbg(dev, + "Waiting for all pending event ring processing to complete\n"); + mhi_event = mhi_cntrl->mhi_event; + for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) { + if (mhi_event->offload_ev) + continue; + tasklet_kill(&mhi_event->task); } + /* Release lock and wait for all pending threads to complete */ + mutex_unlock(&mhi_cntrl->pm_mutex); + dev_dbg(dev, "Waiting for all pending threads to complete\n"); + wake_up_all(&mhi_cntrl->state_event); + + dev_dbg(dev, "Reset all active channels and remove MHI devices\n"); + device_for_each_child(mhi_cntrl->cntrl_dev, NULL, mhi_destroy_device); + + mutex_lock(&mhi_cntrl->pm_mutex); + + WARN_ON(atomic_read(&mhi_cntrl->dev_wake)); + WARN_ON(atomic_read(&mhi_cntrl->pending_pkts)); + + /* Reset the ev rings and cmd rings */ + dev_dbg(dev, "Resetting EV CTXT and CMD CTXT\n"); + mhi_cmd = mhi_cntrl->mhi_cmd; + cmd_ctxt = mhi_cntrl->mhi_ctxt->cmd_ctxt; + for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++, cmd_ctxt++) { + struct mhi_ring *ring = &mhi_cmd->ring; + + ring->rp = ring->base; + ring->wp = ring->base; + cmd_ctxt->rp = cmd_ctxt->rbase; + cmd_ctxt->wp = cmd_ctxt->rbase; + } + + mhi_event = mhi_cntrl->mhi_event; + er_ctxt = mhi_cntrl->mhi_ctxt->er_ctxt; + for (i = 0; i < mhi_cntrl->total_ev_rings; i++, er_ctxt++, + mhi_event++) { + struct mhi_ring *ring = &mhi_event->ring; + + /* Skip offload events */ + if (mhi_event->offload_ev) + continue; + + ring->rp = ring->base; + ring->wp = ring->base; + er_ctxt->rp = er_ctxt->rbase; + er_ctxt->wp = er_ctxt->rbase; + } + + mhi_ready_state_transition(mhi_cntrl); + +exit_sys_error_transition: dev_dbg(dev, "Exiting with PM state: %s, MHI state: %s\n", to_mhi_pm_state_str(mhi_cntrl->pm_state), TO_MHI_STATE_STR(mhi_cntrl->dev_state)); @@ -666,8 +782,7 @@ void mhi_pm_st_worker(struct work_struct *work) mhi_ready_state_transition(mhi_cntrl); break; case DEV_ST_TRANSITION_SYS_ERR: - mhi_pm_disable_transition - (mhi_cntrl, MHI_PM_SYS_ERR_PROCESS); + mhi_pm_sys_error_transition(mhi_cntrl); break; case DEV_ST_TRANSITION_DISABLE: mhi_pm_disable_transition