From patchwork Mon Jul 13 04:57:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Can Guo X-Patchwork-Id: 11658699 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 2167C722 for ; Mon, 13 Jul 2020 05:03:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0393120791 for ; Mon, 13 Jul 2020 05:03:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728779AbgGMFDm (ORCPT ); Mon, 13 Jul 2020 01:03:42 -0400 Received: from labrats.qualcomm.com ([199.106.110.90]:32892 "EHLO labrats.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725826AbgGMFDl (ORCPT ); Mon, 13 Jul 2020 01:03:41 -0400 IronPort-SDR: E/nunR0mpylhFxNg0ie6FP6e0Fm0gCtP9reLOUT6gcklqbQBf1Fme1FxUEP0xUOvSJvPLQxH4T /PULK3L3maObq92x4JccC+ikrd4bI3AEXceKWu12vVvAGkTPqiyv6slLjtRMjIx0R904ELlVl1 oWEdRunycxWvsHPd4kBSDaZ4i2385ap5IahsCmqTQfY3w0Q2cwJh5oO95P7z0x6HkEP1S/w26H 6P6wiFyCUqIVTM1QQlNPcrPuVHkmY7A1Y/MEo6WqcyZhpFOJifpNFZbQl5vSHz4NIcHMaEwPr6 6B4= X-IronPort-AV: E=Sophos;i="5.75,346,1589266800"; d="scan'208";a="47215538" Received: from unknown (HELO ironmsg03-sd.qualcomm.com) ([10.53.140.143]) by labrats.qualcomm.com with ESMTP; 12 Jul 2020 21:57:37 -0700 Received: from pacamara-linux.qualcomm.com ([192.168.140.135]) by ironmsg03-sd.qualcomm.com with ESMTP; 12 Jul 2020 21:57:36 -0700 Received: by pacamara-linux.qualcomm.com (Postfix, from userid 359480) id 5272E22DAF; Sun, 12 Jul 2020 21:57:36 -0700 (PDT) From: Can Guo To: asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, rnayak@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com, saravanak@google.com, salyzyn@google.com, cang@codeaurora.org Cc: Alim Akhtar , Avri Altman , "James E.J. Bottomley" , "Martin K. Petersen" , Stanley Chu , Bean Huo , Nitin Rawat , Tomas Winkler , Bart Van Assche , Satya Tangirala , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v1 4/4] scsi: ufs: Fix up and simplify error recovery mechanism Date: Sun, 12 Jul 2020 21:57:12 -0700 Message-Id: <1594616232-25080-5-git-send-email-cang@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1594616232-25080-1-git-send-email-cang@codeaurora.org> References: <1594616232-25080-1-git-send-email-cang@codeaurora.org> Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Error recovery can be invoked from multiple paths, including hibern8 enter/exit, some vendor vops, ufshcd_eh_host_reset_handler(), resume and eh_work scheduled from IRQ context. Ultimately, these paths are trying to invoke ufshcd_reset_and_restore(), in either sync or async manner. Having both sync and async manners at the same time has some problems - If link recovery happens during clock scaling work, acquring scaling_lock in ufshcd_exec_dev_cmd() would cause dead lock, because scaling_lock is already held by scaling work before link recovery happens. - If link recovery happens during ungate work, ufshcd_hold() would be called recursively. Although commit 53c12d0ef6fcb ("scsi: ufs: fix error recovery after the hibern8 exit failure") fixed a deadlock due to recursive calls of ufshcd_hold() by adding a check of eh_in_progress into ufshcd_hold(), this check added to ufshcd_hold() allows eh_work to run in parallel when link recovery is running. - Similar concurrency can also happen to error recovery invoked from eh_host_reset_handler(), although it tries to protect it from happening by flushing eh_work before start invoking reset and restore, after flush work returns, eh_work can still be scheduled and running in parallel. - Concurrency can even happen between eh_works. eh_work, currently queued on system_wq, is allowed to have multiple instances running in parallel, but we don't have proper protection for that. To fix up and simplify error recovery mechanism, this change mainly does below things o Queue eh_work on a single threaded workqueue to avoid concurrency between eh_works. o According to the UFSHCI JEDEC spec, hibern8 enter/exit error occurs when the link is broken. This actaully applies to any power mode change operations. In this change, if a power mode change operation (including AH8 enter/exit) fails, mark the link state as UIC_LINK_BROKEN_STATE and schedule eh_work. eh_work needs to do full reset and restore to recover the link stack to active. Before the link state is recovered back to active by eh_work, any power mode change attempts just return -ENOLINK to avoid consecutive HW error. o To avoid concurrency between eh_work and link recovery, remove link recovery from hibern8 enter/exit func. If hibern8 enter/exit func fails, simply return error code and let eh_work run in parallel. o Recover UFS hba runtime PM error in eh_work. If ufschd_suspend/resume fails due to UFS error, e.g. hibern8 enter/exit error and SSU cmd error, the runtime PM framework saves the error to dev.power.runtime_error. After that, hba runtime suspend/resume would not be invoked anymore until dev.power.runtime_error is cleared. The runtime PM error can be recovered in eh_work by calling pm_runtime_set_active() after reset and restore succeeds. Meanwhile, if pm_runtime_set_active() returns no error, which means dev.power.runtime_error is cleared, we also need to explicitly resume those scsi devices under hba in case any of them has failed to be resumed due to hba runtime resume error. o Fix a racing problem between eh_work and ufshcd_suspend/resume. In the old code, it blocks scsi requests before schedules eh_work, but when eh_work calls pm_runtime_get_sync(), if ufshcd_suspend/resume is sending a scsi cmd, most likely the SSU cmd, pm_runtime_get_sync() will never return because scsi requests were blocked. To fix this racing problem, o Don't block scsi requests before schedule eh_work, but let eh_work block scsi requests when eh_work is ready to start error recovery. o Meanwhile, if eh_work is schueduled due to fatal error, don't requeue the scsi cmds sent from ufshcd_suspend/resume path, but simply let the scsi cmds fail. If the scsi cmds fail, hba runtime suspend/resume fails too, but it does hurt since eh_work recovers hba runtime PM error. o Move host/regs dump in ufshcd_check_errors() to eh_work because heavy dump in IRQ context can lead to stability issues. In addition, some clean up in ufshcd_print_host_regs() and ufshcd_print_host_state(). Signed-off-by: Can Guo Reported-by: kernel test robot --- drivers/scsi/ufs/ufs-sysfs.c | 1 + drivers/scsi/ufs/ufshcd.c | 441 ++++++++++++++++++++++++++----------------- drivers/scsi/ufs/ufshcd.h | 15 ++ 3 files changed, 284 insertions(+), 173 deletions(-) diff --git a/drivers/scsi/ufs/ufs-sysfs.c b/drivers/scsi/ufs/ufs-sysfs.c index 2d71d23..02d379f00 100644 --- a/drivers/scsi/ufs/ufs-sysfs.c +++ b/drivers/scsi/ufs/ufs-sysfs.c @@ -16,6 +16,7 @@ static const char *ufschd_uic_link_state_to_string( case UIC_LINK_OFF_STATE: return "OFF"; case UIC_LINK_ACTIVE_STATE: return "ACTIVE"; case UIC_LINK_HIBERN8_STATE: return "HIBERN8"; + case UIC_LINK_BROKEN_STATE: return "BROKEN"; default: return "UNKNOWN"; } } diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 33214bb..98bd28b 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -15,6 +15,8 @@ #include #include #include +#include +#include #include "ufshcd.h" #include "ufs_quirks.h" #include "unipro.h" @@ -125,7 +127,8 @@ enum { UFSHCD_STATE_RESET, UFSHCD_STATE_ERROR, UFSHCD_STATE_OPERATIONAL, - UFSHCD_STATE_EH_SCHEDULED, + UFSHCD_STATE_EH_SCHEDULED_FATAL, + UFSHCD_STATE_EH_SCHEDULED_NON_FATAL, }; /* UFSHCD error handling flags */ @@ -228,6 +231,11 @@ static int ufshcd_scale_clks(struct ufs_hba *hba, bool scale_up); static irqreturn_t ufshcd_intr(int irq, void *__hba); static int ufshcd_change_power_mode(struct ufs_hba *hba, struct ufs_pa_layer_attr *pwr_mode); +static void ufshcd_schedule_eh_work(struct ufs_hba *hba); +static int ufshcd_setup_hba_vreg(struct ufs_hba *hba, bool on); +static int ufshcd_setup_vreg(struct ufs_hba *hba, bool on); +static inline int ufshcd_config_vreg_hpm(struct ufs_hba *hba, + struct ufs_vreg *vreg); static int ufshcd_wb_buf_flush_enable(struct ufs_hba *hba); static int ufshcd_wb_buf_flush_disable(struct ufs_hba *hba); static int ufshcd_wb_ctrl(struct ufs_hba *hba, bool enable); @@ -411,15 +419,6 @@ static void ufshcd_print_err_hist(struct ufs_hba *hba, static void ufshcd_print_host_regs(struct ufs_hba *hba) { ufshcd_dump_regs(hba, 0, UFSHCI_REG_SPACE_SIZE, "host_regs: "); - dev_err(hba->dev, "hba->ufs_version = 0x%x, hba->capabilities = 0x%x\n", - hba->ufs_version, hba->capabilities); - dev_err(hba->dev, - "hba->outstanding_reqs = 0x%x, hba->outstanding_tasks = 0x%x\n", - (u32)hba->outstanding_reqs, (u32)hba->outstanding_tasks); - dev_err(hba->dev, - "last_hibern8_exit_tstamp at %lld us, hibern8_exit_cnt = %d\n", - ktime_to_us(hba->ufs_stats.last_hibern8_exit_tstamp), - hba->ufs_stats.hibern8_exit_cnt); ufshcd_print_err_hist(hba, &hba->ufs_stats.pa_err, "pa_err"); ufshcd_print_err_hist(hba, &hba->ufs_stats.dl_err, "dl_err"); @@ -499,6 +498,8 @@ static void ufshcd_print_tmrs(struct ufs_hba *hba, unsigned long bitmap) static void ufshcd_print_host_state(struct ufs_hba *hba) { + struct scsi_device *sdev_ufs = hba->sdev_ufs_device; + dev_err(hba->dev, "UFS Host state=%d\n", hba->ufshcd_state); dev_err(hba->dev, "outstanding reqs=0x%lx tasks=0x%lx\n", hba->outstanding_reqs, hba->outstanding_tasks); @@ -511,12 +512,22 @@ static void ufshcd_print_host_state(struct ufs_hba *hba) dev_err(hba->dev, "Auto BKOPS=%d, Host self-block=%d\n", hba->auto_bkops_enabled, hba->host->host_self_blocked); dev_err(hba->dev, "Clk gate=%d\n", hba->clk_gating.state); + dev_err(hba->dev, + "last_hibern8_exit_tstamp at %lld us, hibern8_exit_cnt = %d\n", + ktime_to_us(hba->ufs_stats.last_hibern8_exit_tstamp), + hba->ufs_stats.hibern8_exit_cnt); + dev_err(hba->dev, "last intr ts=%lld, last intr status=0x%x\n", + ktime_to_us(hba->ufs_stats.last_intr_ts), + hba->ufs_stats.last_intr_status); dev_err(hba->dev, "error handling flags=0x%x, req. abort count=%d\n", hba->eh_flags, hba->req_abort_count); - dev_err(hba->dev, "Host capabilities=0x%x, caps=0x%x\n", - hba->capabilities, hba->caps); + dev_err(hba->dev, "hba->ufs_version=0x%x, Host capabilities=0x%x, caps=0x%x\n", + hba->ufs_version, hba->capabilities, hba->caps); dev_err(hba->dev, "quirks=0x%x, dev. quirks=0x%x\n", hba->quirks, hba->dev_quirks); + if (sdev_ufs) + dev_err(hba->dev, "UFS dev info: %.8s %.16s rev %.4s\n", + sdev_ufs->vendor, sdev_ufs->model, sdev_ufs->rev); } /** @@ -1568,11 +1579,6 @@ int ufshcd_hold(struct ufs_hba *hba, bool async) spin_lock_irqsave(hba->host->host_lock, flags); hba->clk_gating.active_reqs++; - if (ufshcd_eh_in_progress(hba)) { - spin_unlock_irqrestore(hba->host->host_lock, flags); - return 0; - } - start: switch (hba->clk_gating.state) { case CLKS_ON: @@ -1647,6 +1653,7 @@ EXPORT_SYMBOL_GPL(ufshcd_hold); static void ufshcd_gate_work(struct work_struct *work) { + int ret; struct ufs_hba *hba = container_of(work, struct ufs_hba, clk_gating.gate_work.work); unsigned long flags; @@ -1676,8 +1683,11 @@ static void ufshcd_gate_work(struct work_struct *work) /* put the link into hibern8 mode before turning off clocks */ if (ufshcd_can_hibern8_during_gating(hba)) { - if (ufshcd_uic_hibern8_enter(hba)) { + ret = ufshcd_uic_hibern8_enter(hba); + if (ret) { hba->clk_gating.state = CLKS_ON; + dev_err(hba->dev, "%s: hibern8 enter failed %d\n", + __func__, ret); trace_ufshcd_clk_gating(dev_name(hba->dev), hba->clk_gating.state); goto out; @@ -1725,8 +1735,7 @@ static void __ufshcd_release(struct ufs_hba *hba) if (hba->clk_gating.active_reqs || hba->clk_gating.is_suspended || hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL || ufshcd_any_tag_in_use(hba) || hba->outstanding_tasks - || hba->active_uic_cmd || hba->uic_async_done - || ufshcd_eh_in_progress(hba)) + || hba->active_uic_cmd || hba->uic_async_done) return; hba->clk_gating.state = REQ_CLKS_OFF; @@ -2505,34 +2514,6 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) if (!down_read_trylock(&hba->clk_scaling_lock)) return SCSI_MLQUEUE_HOST_BUSY; - spin_lock_irqsave(hba->host->host_lock, flags); - switch (hba->ufshcd_state) { - case UFSHCD_STATE_OPERATIONAL: - break; - case UFSHCD_STATE_EH_SCHEDULED: - case UFSHCD_STATE_RESET: - err = SCSI_MLQUEUE_HOST_BUSY; - goto out_unlock; - case UFSHCD_STATE_ERROR: - set_host_byte(cmd, DID_ERROR); - cmd->scsi_done(cmd); - goto out_unlock; - default: - dev_WARN_ONCE(hba->dev, 1, "%s: invalid state %d\n", - __func__, hba->ufshcd_state); - set_host_byte(cmd, DID_BAD_TARGET); - cmd->scsi_done(cmd); - goto out_unlock; - } - - /* if error handling is in progress, don't issue commands */ - if (ufshcd_eh_in_progress(hba)) { - set_host_byte(cmd, DID_ERROR); - cmd->scsi_done(cmd); - goto out_unlock; - } - spin_unlock_irqrestore(hba->host->host_lock, flags); - hba->req_abort_count = 0; err = ufshcd_hold(hba, true); @@ -2568,12 +2549,52 @@ static int ufshcd_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *cmd) /* Make sure descriptors are ready before ringing the doorbell */ wmb(); - /* issue command to the controller */ spin_lock_irqsave(hba->host->host_lock, flags); + switch (hba->ufshcd_state) { + case UFSHCD_STATE_OPERATIONAL: + case UFSHCD_STATE_EH_SCHEDULED_NON_FATAL: + break; + case UFSHCD_STATE_EH_SCHEDULED_FATAL: + /* + * If we are here, eh_work is either scheduled or running. + * Before eh_work sets ufshcd_state to STATE_RESET, it flushes + * runtime PM ops by calling pm_runtime_get_sync(). If a scsi + * cmd, e.g. the SSU cmd, is sent by PM ops, it can never be + * finished if we let SCSI layer keep retrying it, which gets + * eh_work stuck forever. Neither can we let it pass, because + * ufs now is not in good status, so the SSU cmd may eventually + * time out, blocking eh_work for too long. So just let it fail. + */ + if (hba->pm_op_in_progress) { + hba->force_reset = true; + set_host_byte(cmd, DID_BAD_TARGET); + goto out_compl_cmd; + } + /* fallthrough */ + case UFSHCD_STATE_RESET: + err = SCSI_MLQUEUE_HOST_BUSY; + goto out_compl_cmd; + case UFSHCD_STATE_ERROR: + set_host_byte(cmd, DID_ERROR); + goto out_compl_cmd; + default: + dev_WARN_ONCE(hba->dev, 1, "%s: invalid state %d\n", + __func__, hba->ufshcd_state); + set_host_byte(cmd, DID_BAD_TARGET); + goto out_compl_cmd; + } ufshcd_vops_setup_xfer_req(hba, tag, true); ufshcd_send_command(hba, tag); -out_unlock: spin_unlock_irqrestore(hba->host->host_lock, flags); + goto out; + +out_compl_cmd: + scsi_dma_unmap(lrbp->cmd); + lrbp->cmd = NULL; + spin_unlock_irqrestore(hba->host->host_lock, flags); + ufshcd_release(hba); + if (!err) + cmd->scsi_done(cmd); out: up_read(&hba->clk_scaling_lock); return err; @@ -3746,6 +3767,10 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd) ufshcd_add_delay_before_dme_cmd(hba); spin_lock_irqsave(hba->host->host_lock, flags); + if (ufshcd_is_link_broken(hba)) { + ret = -ENOLINK; + goto out_unlock; + } hba->uic_async_done = &uic_async_done; if (ufshcd_readl(hba, REG_INTERRUPT_ENABLE) & UIC_COMMAND_COMPL) { ufshcd_disable_intr(hba, UIC_COMMAND_COMPL); @@ -3793,6 +3818,12 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd) hba->uic_async_done = NULL; if (reenable_intr) ufshcd_enable_intr(hba, UIC_COMMAND_COMPL); + if (ret) { + ufshcd_set_link_broken(hba); + ufshcd_schedule_eh_work(hba); + } + +out_unlock: spin_unlock_irqrestore(hba->host->host_lock, flags); mutex_unlock(&hba->uic_cmd_mutex); @@ -3862,7 +3893,7 @@ int ufshcd_link_recovery(struct ufs_hba *hba) } EXPORT_SYMBOL_GPL(ufshcd_link_recovery); -static int __ufshcd_uic_hibern8_enter(struct ufs_hba *hba) +static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba) { int ret; struct uic_command uic_cmd = {0}; @@ -3875,45 +3906,16 @@ static int __ufshcd_uic_hibern8_enter(struct ufs_hba *hba) trace_ufshcd_profile_hibern8(dev_name(hba->dev), "enter", ktime_to_us(ktime_sub(ktime_get(), start)), ret); - if (ret) { - int err; - + if (ret) dev_err(hba->dev, "%s: hibern8 enter failed. ret = %d\n", __func__, ret); - - /* - * If link recovery fails then return error code returned from - * ufshcd_link_recovery(). - * If link recovery succeeds then return -EAGAIN to attempt - * hibern8 enter retry again. - */ - err = ufshcd_link_recovery(hba); - if (err) { - dev_err(hba->dev, "%s: link recovery failed", __func__); - ret = err; - } else { - ret = -EAGAIN; - } - } else + else ufshcd_vops_hibern8_notify(hba, UIC_CMD_DME_HIBER_ENTER, POST_CHANGE); return ret; } -static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba) -{ - int ret = 0, retries; - - for (retries = UIC_HIBERN8_ENTER_RETRIES; retries > 0; retries--) { - ret = __ufshcd_uic_hibern8_enter(hba); - if (!ret) - goto out; - } -out: - return ret; -} - int ufshcd_uic_hibern8_exit(struct ufs_hba *hba) { struct uic_command uic_cmd = {0}; @@ -3930,7 +3932,6 @@ int ufshcd_uic_hibern8_exit(struct ufs_hba *hba) if (ret) { dev_err(hba->dev, "%s: hibern8 exit failed. ret = %d\n", __func__, ret); - ret = ufshcd_link_recovery(hba); } else { ufshcd_vops_hibern8_notify(hba, UIC_CMD_DME_HIBER_EXIT, POST_CHANGE); @@ -5554,6 +5555,28 @@ static bool ufshcd_quirk_dl_nac_errors(struct ufs_hba *hba) return err_handling; } +/* host lock must be held before calling this func */ +static inline bool ufshcd_is_saved_err_fatal(struct ufs_hba *hba) +{ + return ((hba->saved_err & INT_FATAL_ERRORS) || + ((hba->saved_err & UIC_ERROR) && + (hba->saved_uic_err & UFSHCD_UIC_DL_PA_INIT_ERROR))); +} + +/* host lock must be held before calling this func */ +static inline void ufshcd_schedule_eh_work(struct ufs_hba *hba) +{ + /* handle fatal errors only when link is not in error state */ + if (hba->ufshcd_state != UFSHCD_STATE_ERROR) { + if (hba->force_reset || ufshcd_is_link_broken(hba) || + ufshcd_is_saved_err_fatal(hba)) + hba->ufshcd_state = UFSHCD_STATE_EH_SCHEDULED_FATAL; + else + hba->ufshcd_state = UFSHCD_STATE_EH_SCHEDULED_NON_FATAL; + queue_work(hba->eh_wq, &hba->eh_work); + } +} + /** * ufshcd_err_handler - handle UFS errors that require s/w attention * @work: pointer to work structure @@ -5561,24 +5584,53 @@ static bool ufshcd_quirk_dl_nac_errors(struct ufs_hba *hba) static void ufshcd_err_handler(struct work_struct *work) { struct ufs_hba *hba; + struct Scsi_Host *shost; + struct scsi_device *sdev; unsigned long flags; u32 err_xfer = 0; u32 err_tm = 0; - int err = 0; + int reset_err = -1; int tag; bool needs_reset = false; hba = container_of(work, struct ufs_hba, eh_work); + shost = hba->host; + spin_lock_irqsave(hba->host->host_lock, flags); + if ((hba->ufshcd_state == UFSHCD_STATE_ERROR) || + (!(hba->saved_err || hba->saved_uic_err || hba->force_reset) && + !ufshcd_is_link_broken(hba))) { + if (hba->ufshcd_state != UFSHCD_STATE_ERROR) + hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL; + spin_unlock_irqrestore(hba->host->host_lock, flags); + return; + } + ufshcd_set_eh_in_progress(hba); + spin_unlock_irqrestore(hba->host->host_lock, flags); pm_runtime_get_sync(hba->dev); + /* + * Don't assume anything of pm_runtime_get_sync(), if resume fails, + * irq and clocks can be OFF, and powers can be OFF or in LPM. + */ + ufshcd_setup_vreg(hba, true); + ufshcd_config_vreg_hpm(hba, hba->vreg_info.vccq); + ufshcd_config_vreg_hpm(hba, hba->vreg_info.vccq2); + ufshcd_setup_hba_vreg(hba, true); + ufshcd_enable_irq(hba); + ufshcd_hold(hba, false); + if (!ufshcd_is_clkgating_allowed(hba)) + ufshcd_setup_clocks(hba, true); - spin_lock_irqsave(hba->host->host_lock, flags); - if (hba->ufshcd_state == UFSHCD_STATE_RESET) - goto out; + if (ufshcd_is_clkscaling_supported(hba)) { + cancel_work_sync(&hba->clk_scaling.suspend_work); + cancel_work_sync(&hba->clk_scaling.resume_work); + ufshcd_suspend_clkscaling(hba); + } + spin_lock_irqsave(hba->host->host_lock, flags); + ufshcd_scsi_block_requests(hba); hba->ufshcd_state = UFSHCD_STATE_RESET; - ufshcd_set_eh_in_progress(hba); /* Complete requests that have door-bell cleared by h/w */ ufshcd_complete_requests(hba); @@ -5590,17 +5642,29 @@ static void ufshcd_err_handler(struct work_struct *work) /* release the lock as ufshcd_quirk_dl_nac_errors() may sleep */ ret = ufshcd_quirk_dl_nac_errors(hba); spin_lock_irqsave(hba->host->host_lock, flags); - if (!ret) + if (!ret && !hba->force_reset && ufshcd_is_link_active(hba)) goto skip_err_handling; } - if ((hba->saved_err & INT_FATAL_ERRORS) || - (hba->saved_err & UFSHCD_UIC_HIBERN8_MASK) || + + if (hba->force_reset || ufshcd_is_link_broken(hba) || + ufshcd_is_saved_err_fatal(hba) || ((hba->saved_err & UIC_ERROR) && - (hba->saved_uic_err & (UFSHCD_UIC_DL_PA_INIT_ERROR | - UFSHCD_UIC_DL_NAC_RECEIVED_ERROR | - UFSHCD_UIC_DL_TCx_REPLAY_ERROR)))) + (hba->saved_uic_err & (UFSHCD_UIC_DL_NAC_RECEIVED_ERROR | + UFSHCD_UIC_DL_TCx_REPLAY_ERROR)))) needs_reset = true; + if (hba->saved_err & (INT_FATAL_ERRORS | UIC_ERROR | + UFSHCD_UIC_HIBERN8_MASK)) { + dev_err(hba->dev, "%s: saved_err 0x%x saved_uic_err 0x%x\n", + __func__, hba->saved_err, hba->saved_uic_err); + spin_unlock_irqrestore(hba->host->host_lock, flags); + ufshcd_print_host_state(hba); + ufshcd_print_pwr_info(hba); + ufshcd_print_host_regs(hba); + ufshcd_print_tmrs(hba, hba->outstanding_tasks); + spin_lock_irqsave(hba->host->host_lock, flags); + } + /* * if host reset is required then skip clearing the pending * transfers forcefully because they will get cleared during @@ -5652,38 +5716,63 @@ static void ufshcd_err_handler(struct work_struct *work) __ufshcd_transfer_req_compl(hba, (1UL << (hba->nutrs - 1))); + hba->force_reset = false; spin_unlock_irqrestore(hba->host->host_lock, flags); - err = ufshcd_reset_and_restore(hba); + reset_err = ufshcd_reset_and_restore(hba); spin_lock_irqsave(hba->host->host_lock, flags); - if (err) { + if (reset_err) dev_err(hba->dev, "%s: reset and restore failed\n", __func__); - hba->ufshcd_state = UFSHCD_STATE_ERROR; - } - /* - * Inform scsi mid-layer that we did reset and allow to handle - * Unit Attention properly. - */ - scsi_report_bus_reset(hba->host, 0); - hba->saved_err = 0; - hba->saved_uic_err = 0; } skip_err_handling: if (!needs_reset) { - hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL; + if (hba->ufshcd_state == UFSHCD_STATE_RESET) + hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL; if (hba->saved_err || hba->saved_uic_err) dev_err_ratelimited(hba->dev, "%s: exit: saved_err 0x%x saved_uic_err 0x%x", __func__, hba->saved_err, hba->saved_uic_err); } - ufshcd_clear_eh_in_progress(hba); + if (!reset_err) { + int ret; + struct request_queue *q; -out: + spin_unlock_irqrestore(hba->host->host_lock, flags); + /* + * Set RPM status of hba device to RPM_ACTIVE, + * this also clears its runtime error. + */ + ret = pm_runtime_set_active(hba->dev); + /* + * If hba device had runtime error, explicitly resume + * its scsi devices so that block layer can wake up + * those waiting in blk_queue_enter(). + */ + if (!ret) { + list_for_each_entry(sdev, &shost->__devices, siblings) { + q = sdev->request_queue; + if (q->dev && (q->rpm_status == RPM_SUSPENDED || + q->rpm_status == RPM_SUSPENDING)) + pm_request_resume(q->dev); + } + } + spin_lock_irqsave(hba->host->host_lock, flags); + } + + /* If clk_gating is held by pm ops, release it */ + if (pm_runtime_active(hba->dev) && hba->clk_gating.held_by_pm) { + hba->clk_gating.held_by_pm = false; + __ufshcd_release(hba); + } + + ufshcd_clear_eh_in_progress(hba); spin_unlock_irqrestore(hba->host->host_lock, flags); ufshcd_scsi_unblock_requests(hba); ufshcd_release(hba); - pm_runtime_put_sync(hba->dev); + if (ufshcd_is_clkscaling_supported(hba)) + ufshcd_resume_clkscaling(hba); + pm_runtime_put_noidle(hba->dev); } /** @@ -5813,6 +5902,7 @@ static irqreturn_t ufshcd_check_errors(struct ufs_hba *hba) hba->errors, ufshcd_get_upmcrs(hba)); ufshcd_update_reg_hist(&hba->ufs_stats.auto_hibern8_err, hba->errors); + ufshcd_set_link_broken(hba); queue_eh_work = true; } @@ -5823,31 +5913,7 @@ static irqreturn_t ufshcd_check_errors(struct ufs_hba *hba) */ hba->saved_err |= hba->errors; hba->saved_uic_err |= hba->uic_error; - - /* handle fatal errors only when link is functional */ - if (hba->ufshcd_state == UFSHCD_STATE_OPERATIONAL) { - /* block commands from scsi mid-layer */ - ufshcd_scsi_block_requests(hba); - - hba->ufshcd_state = UFSHCD_STATE_EH_SCHEDULED; - - /* dump controller state before resetting */ - if (hba->saved_err & (INT_FATAL_ERRORS | UIC_ERROR)) { - bool pr_prdt = !!(hba->saved_err & - SYSTEM_BUS_FATAL_ERROR); - - dev_err(hba->dev, "%s: saved_err 0x%x saved_uic_err 0x%x\n", - __func__, hba->saved_err, - hba->saved_uic_err); - - ufshcd_print_host_regs(hba); - ufshcd_print_pwr_info(hba); - ufshcd_print_tmrs(hba, hba->outstanding_tasks); - ufshcd_print_trs(hba, hba->outstanding_reqs, - pr_prdt); - } - schedule_work(&hba->eh_work); - } + ufshcd_schedule_eh_work(hba); retval |= IRQ_HANDLED; } /* @@ -5951,6 +6017,8 @@ static irqreturn_t ufshcd_intr(int irq, void *__hba) spin_lock(hba->host->host_lock); intr_status = ufshcd_readl(hba, REG_INTERRUPT_STATUS); + hba->ufs_stats.last_intr_status = intr_status; + hba->ufs_stats.last_intr_ts = ktime_get(); /* * There could be max of hba->nutrs reqs in flight and in worst case @@ -6589,9 +6657,6 @@ static int ufshcd_host_reset_and_restore(struct ufs_hba *hba) /* Establish the link again and restore the device */ err = ufshcd_probe_hba(hba, false); - - if (!err && (hba->ufshcd_state != UFSHCD_STATE_OPERATIONAL)) - err = -EIO; out: if (err) dev_err(hba->dev, "%s: Host init failed %d\n", __func__, err); @@ -6610,9 +6675,23 @@ static int ufshcd_host_reset_and_restore(struct ufs_hba *hba) */ static int ufshcd_reset_and_restore(struct ufs_hba *hba) { + u32 saved_err; + u32 saved_uic_err; int err = 0; + unsigned long flags; int retries = MAX_HOST_RESET_RETRIES; + /* + * This is a fresh start, cache and clear saved error first, + * in case new error generated during reset and restore. + */ + spin_lock_irqsave(hba->host->host_lock, flags); + saved_err = hba->saved_err; + saved_uic_err = hba->saved_uic_err; + hba->saved_err = 0; + hba->saved_uic_err = 0; + spin_unlock_irqrestore(hba->host->host_lock, flags); + do { /* Reset the attached device */ ufshcd_vops_device_reset(hba); @@ -6620,6 +6699,19 @@ static int ufshcd_reset_and_restore(struct ufs_hba *hba) err = ufshcd_host_reset_and_restore(hba); } while (err && --retries); + spin_lock_irqsave(hba->host->host_lock, flags); + /* + * Inform scsi mid-layer that we did reset and allow to handle + * Unit Attention properly. + */ + scsi_report_bus_reset(hba->host, 0); + if (err) { + hba->ufshcd_state = UFSHCD_STATE_ERROR; + hba->saved_err |= saved_err; + hba->saved_uic_err |= saved_uic_err; + } + spin_unlock_irqrestore(hba->host->host_lock, flags); + return err; } @@ -6631,48 +6723,25 @@ static int ufshcd_reset_and_restore(struct ufs_hba *hba) */ static int ufshcd_eh_host_reset_handler(struct scsi_cmnd *cmd) { - int err; + int err = SUCCESS; unsigned long flags; struct ufs_hba *hba; hba = shost_priv(cmd->device->host); - ufshcd_hold(hba, false); - /* - * Check if there is any race with fatal error handling. - * If so, wait for it to complete. Even though fatal error - * handling does reset and restore in some cases, don't assume - * anything out of it. We are just avoiding race here. - */ - do { - spin_lock_irqsave(hba->host->host_lock, flags); - if (!(work_pending(&hba->eh_work) || - hba->ufshcd_state == UFSHCD_STATE_RESET || - hba->ufshcd_state == UFSHCD_STATE_EH_SCHEDULED)) - break; - spin_unlock_irqrestore(hba->host->host_lock, flags); - dev_dbg(hba->dev, "%s: reset in progress\n", __func__); - flush_work(&hba->eh_work); - } while (1); - - hba->ufshcd_state = UFSHCD_STATE_RESET; - ufshcd_set_eh_in_progress(hba); + spin_lock_irqsave(hba->host->host_lock, flags); + hba->force_reset = true; + ufshcd_schedule_eh_work(hba); + dev_err(hba->dev, "%s: reset in progress - 1\n", __func__); spin_unlock_irqrestore(hba->host->host_lock, flags); - err = ufshcd_reset_and_restore(hba); + flush_work(&hba->eh_work); spin_lock_irqsave(hba->host->host_lock, flags); - if (!err) { - err = SUCCESS; - hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL; - } else { + if (hba->ufshcd_state == UFSHCD_STATE_ERROR) err = FAILED; - hba->ufshcd_state = UFSHCD_STATE_ERROR; - } - ufshcd_clear_eh_in_progress(hba); spin_unlock_irqrestore(hba->host->host_lock, flags); - ufshcd_release(hba); return err; } @@ -7393,6 +7462,7 @@ static int ufshcd_add_lus(struct ufs_hba *hba) static int ufshcd_probe_hba(struct ufs_hba *hba, bool async) { int ret; + unsigned long flags; ktime_t start = ktime_get(); ret = ufshcd_link_startup(hba); @@ -7458,7 +7528,10 @@ static int ufshcd_probe_hba(struct ufs_hba *hba, bool async) ufshcd_set_active_icc_lvl(hba); /* set the state as operational after switching to desired gear */ - hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL; + spin_lock_irqsave(hba->host->host_lock, flags); + if (hba->ufshcd_state == UFSHCD_STATE_RESET) + hba->ufshcd_state = UFSHCD_STATE_OPERATIONAL; + spin_unlock_irqrestore(hba->host->host_lock, flags); ufshcd_wb_config(hba); /* Enable Auto-Hibernate if configured */ @@ -8071,10 +8144,13 @@ static int ufshcd_link_state_transition(struct ufs_hba *hba, if (req_link_state == UIC_LINK_HIBERN8_STATE) { ret = ufshcd_uic_hibern8_enter(hba); - if (!ret) + if (!ret) { ufshcd_set_link_hibern8(hba); - else + } else { + dev_err(hba->dev, "%s: hibern8 enter failed %d\n", + __func__, ret); goto out; + } } /* * If autobkops is enabled, link can't be turned off because @@ -8090,8 +8166,11 @@ static int ufshcd_link_state_transition(struct ufs_hba *hba, * unipro. But putting the link in hibern8 is much faster. */ ret = ufshcd_uic_hibern8_enter(hba); - if (ret) + if (ret) { + dev_err(hba->dev, "%s: hibern8 enter failed %d\n", + __func__, ret); goto out; + } /* * Change controller state to "reset state" which * should also put the link in off/reset state @@ -8226,6 +8305,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op) * just gate the clocks. */ ufshcd_hold(hba, false); + hba->clk_gating.held_by_pm = true; hba->clk_gating.is_suspended = true; if (hba->clk_scaling.is_allowed) { @@ -8345,6 +8425,7 @@ static int ufshcd_suspend(struct ufs_hba *hba, enum ufs_pm_op pm_op) hba->clk_gating.is_suspended = false; hba->dev_info.b_rpm_dev_flush_capable = false; ufshcd_release(hba); + hba->clk_gating.held_by_pm = false; out: if (hba->dev_info.b_rpm_dev_flush_capable) { schedule_delayed_work(&hba->rpm_dev_flush_recheck_work, @@ -8400,10 +8481,13 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op) if (ufshcd_is_link_hibern8(hba)) { ret = ufshcd_uic_hibern8_exit(hba); - if (!ret) + if (!ret) { ufshcd_set_link_active(hba); - else + } else { + dev_err(hba->dev, "%s: hibern8 exit failed %d\n", + __func__, ret); goto vendor_suspend; + } } else if (ufshcd_is_link_off(hba)) { /* * A full initialization of the host and the device is @@ -8448,6 +8532,7 @@ static int ufshcd_resume(struct ufs_hba *hba, enum ufs_pm_op pm_op) /* Schedule clock gating in case of no access to UFS device yet */ ufshcd_release(hba); + hba->clk_gating.held_by_pm = false; goto out; @@ -8777,6 +8862,7 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) int err; struct Scsi_Host *host = hba->host; struct device *dev = hba->dev; + char eh_wq_name[sizeof("ufs_eh_wq_00")]; if (!mmio_base) { dev_err(hba->dev, @@ -8838,6 +8924,15 @@ int ufshcd_init(struct ufs_hba *hba, void __iomem *mmio_base, unsigned int irq) hba->max_pwr_info.is_valid = false; /* Initialize work queues */ + snprintf(eh_wq_name, sizeof(eh_wq_name), "ufs_eh_wq_%d", + hba->host->host_no); + hba->eh_wq = create_singlethread_workqueue(eh_wq_name); + if (!hba->eh_wq) { + dev_err(hba->dev, "%s: failed to create eh workqueue\n", + __func__); + err = -ENOMEM; + goto out_disable; + } INIT_WORK(&hba->eh_work, ufshcd_err_handler); INIT_WORK(&hba->eeh_work, ufshcd_exception_event_handler); diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h index 656c069..585e58b 100644 --- a/drivers/scsi/ufs/ufshcd.h +++ b/drivers/scsi/ufs/ufshcd.h @@ -90,6 +90,7 @@ enum uic_link_state { UIC_LINK_OFF_STATE = 0, /* Link powered down or disabled */ UIC_LINK_ACTIVE_STATE = 1, /* Link is in Fast/Slow/Sleep state */ UIC_LINK_HIBERN8_STATE = 2, /* Link is in Hibernate state */ + UIC_LINK_BROKEN_STATE = 3, /* Link is in broken state */ }; #define ufshcd_is_link_off(hba) ((hba)->uic_link_state == UIC_LINK_OFF_STATE) @@ -97,11 +98,15 @@ enum uic_link_state { UIC_LINK_ACTIVE_STATE) #define ufshcd_is_link_hibern8(hba) ((hba)->uic_link_state == \ UIC_LINK_HIBERN8_STATE) +#define ufshcd_is_link_broken(hba) ((hba)->uic_link_state == \ + UIC_LINK_BROKEN_STATE) #define ufshcd_set_link_off(hba) ((hba)->uic_link_state = UIC_LINK_OFF_STATE) #define ufshcd_set_link_active(hba) ((hba)->uic_link_state = \ UIC_LINK_ACTIVE_STATE) #define ufshcd_set_link_hibern8(hba) ((hba)->uic_link_state = \ UIC_LINK_HIBERN8_STATE) +#define ufshcd_set_link_broken(hba) ((hba)->uic_link_state = \ + UIC_LINK_BROKEN_STATE) #define ufshcd_set_ufs_dev_active(h) \ ((h)->curr_dev_pwr_mode = UFS_ACTIVE_PWR_MODE) @@ -349,6 +354,7 @@ struct ufs_clk_gating { struct device_attribute delay_attr; struct device_attribute enable_attr; bool is_enabled; + bool held_by_pm; int active_reqs; struct workqueue_struct *clk_gating_workq; }; @@ -406,6 +412,8 @@ struct ufs_err_reg_hist { /** * struct ufs_stats - keeps usage/err statistics + * @last_intr_status: record the last interrupt status. + * @last_intr_ts: record the last interrupt timestamp. * @hibern8_exit_cnt: Counter to keep track of number of exits, * reset this after link-startup. * @last_hibern8_exit_tstamp: Set time after the hibern8 exit. @@ -425,6 +433,9 @@ struct ufs_err_reg_hist { * @tsk_abort: tracks task abort events */ struct ufs_stats { + u32 last_intr_status; + ktime_t last_intr_ts; + u32 hibern8_exit_cnt; ktime_t last_hibern8_exit_tstamp; @@ -608,12 +619,14 @@ struct ufs_hba_variant_params { * @intr_mask: Interrupt Mask Bits * @ee_ctrl_mask: Exception event control mask * @is_powered: flag to check if HBA is powered + * @eh_wq: Workqueue that eh_work works on * @eh_work: Worker to handle UFS errors that require s/w attention * @eeh_work: Worker to handle exception events * @errors: HBA errors * @uic_error: UFS interconnect layer error status * @saved_err: sticky error mask * @saved_uic_err: sticky UIC error mask + * @force_reset: flag to force eh_work perform a full reset * @silence_err_logs: flag to silence error logs * @dev_cmd: ufs device management command information * @last_dme_cmd_tstamp: time stamp of the last completed DME command @@ -702,6 +715,7 @@ struct ufs_hba { bool is_powered; /* Work Queues */ + struct workqueue_struct *eh_wq; struct work_struct eh_work; struct work_struct eeh_work; @@ -711,6 +725,7 @@ struct ufs_hba { u32 saved_err; u32 saved_uic_err; struct ufs_stats ufs_stats; + bool force_reset; bool silence_err_logs; /* Device management request data */