Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755349AbbH0Mnj (ORCPT ); Thu, 27 Aug 2015 08:43:39 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:39370 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754770AbbH0MmC (ORCPT ); Thu, 27 Aug 2015 08:42:02 -0400 From: Yaniv Gardi To: robherring2@gmail.com, James.Bottomley@HansenPartnership.com, pebolle@tiscali.nl, hch@infradead.org Cc: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, linux-arm-msm@vger.kernel.org, santoshsy@gmail.com, linux-scsi-owner@vger.kernel.org, subhashj@codeaurora.org, ygardi@codeaurora.org, gbroner@codeaurora.org, draviv@codeaurora.org, Vinayak Holikatti , "James E.J. Bottomley" Subject: [PATCH v2 12/15] scsi: ufs: reduce the interrupts for power mode change requests Date: Thu, 27 Aug 2015 15:41:03 +0300 Message-Id: <1440679266-13218-13-git-send-email-ygardi@codeaurora.org> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1440679266-13218-1-git-send-email-ygardi@codeaurora.org> References: <1440679266-13218-1-git-send-email-ygardi@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4933 Lines: 135 DME commands such as Hibern8 enter/exit and gear switch generate 2 completion interrupts, one for confirmation that command is received by local UniPro and 2nd one is the final confirmation after communication with remote UniPro. Currently both of these completions are registered as interrupt events which is not quite necessary and instead we can just wait for the interrupt of 2nd completion, this should reduce the number of interrupts and could reduce the unnecessary CPU wakeups to handle extra interrupts. Signed-off-by: Subhash Jadavani Signed-off-by: Yaniv Gardi --- drivers/scsi/ufs/ufshcd.c | 41 +++++++++++++++++++++++++++-------------- 1 file changed, 27 insertions(+), 14 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index f2d4301..fc2a52d 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -986,13 +986,15 @@ ufshcd_wait_for_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) * __ufshcd_send_uic_cmd - Send UIC commands and retrieve the result * @hba: per adapter instance * @uic_cmd: UIC command + * @completion: initialize the completion only if this is set to true * * Identical to ufshcd_send_uic_cmd() expect mutex. Must be called * with mutex held and host_lock locked. * Returns 0 only if success. */ static int -__ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) +__ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd, + bool completion) { if (!ufshcd_ready_for_uic_cmd(hba)) { dev_err(hba->dev, @@ -1000,7 +1002,8 @@ __ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) return -EIO; } - init_completion(&uic_cmd->done); + if (completion) + init_completion(&uic_cmd->done); ufshcd_dispatch_uic_cmd(hba, uic_cmd); @@ -1025,7 +1028,7 @@ ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) ufshcd_add_delay_before_dme_cmd(hba); spin_lock_irqsave(hba->host->host_lock, flags); - ret = __ufshcd_send_uic_cmd(hba, uic_cmd); + ret = __ufshcd_send_uic_cmd(hba, uic_cmd, true); spin_unlock_irqrestore(hba->host->host_lock, flags); if (!ret) ret = ufshcd_wait_for_uic_cmd(hba, uic_cmd); @@ -2346,6 +2349,7 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd) unsigned long flags; u8 status; int ret; + bool reenable_intr = false; mutex_lock(&hba->uic_cmd_mutex); init_completion(&uic_async_done); @@ -2353,15 +2357,17 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd) spin_lock_irqsave(hba->host->host_lock, flags); hba->uic_async_done = &uic_async_done; - ret = __ufshcd_send_uic_cmd(hba, cmd); - spin_unlock_irqrestore(hba->host->host_lock, flags); - if (ret) { - dev_err(hba->dev, - "pwr ctrl cmd 0x%x with mode 0x%x uic error %d\n", - cmd->command, cmd->argument3, ret); - goto out; + if (ufshcd_readl(hba, REG_INTERRUPT_ENABLE) & UIC_COMMAND_COMPL) { + ufshcd_disable_intr(hba, UIC_COMMAND_COMPL); + /* + * Make sure UIC command completion interrupt is disabled before + * issuing UIC command. + */ + wmb(); + reenable_intr = true; } - ret = ufshcd_wait_for_uic_cmd(hba, cmd); + ret = __ufshcd_send_uic_cmd(hba, cmd, false); + spin_unlock_irqrestore(hba->host->host_lock, flags); if (ret) { dev_err(hba->dev, "pwr ctrl cmd 0x%x with mode 0x%x uic error %d\n", @@ -2387,7 +2393,10 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd) } out: spin_lock_irqsave(hba->host->host_lock, flags); + hba->active_uic_cmd = NULL; hba->uic_async_done = NULL; + if (reenable_intr) + ufshcd_enable_intr(hba, UIC_COMMAND_COMPL); spin_unlock_irqrestore(hba->host->host_lock, flags); mutex_unlock(&hba->uic_cmd_mutex); @@ -3812,16 +3821,20 @@ static void ufshcd_sl_intr(struct ufs_hba *hba, u32 intr_status) */ static irqreturn_t ufshcd_intr(int irq, void *__hba) { - u32 intr_status; + u32 intr_status, enabled_intr_status; irqreturn_t retval = IRQ_NONE; struct ufs_hba *hba = __hba; spin_lock(hba->host->host_lock); intr_status = ufshcd_readl(hba, REG_INTERRUPT_STATUS); + enabled_intr_status = + intr_status & ufshcd_readl(hba, REG_INTERRUPT_ENABLE); - if (intr_status) { + if (intr_status) ufshcd_writel(hba, intr_status, REG_INTERRUPT_STATUS); - ufshcd_sl_intr(hba, intr_status); + + if (enabled_intr_status) { + ufshcd_sl_intr(hba, enabled_intr_status); retval = IRQ_HANDLED; } spin_unlock(hba->host->host_lock); -- 1.8.5.2 -- QUALCOMM ISRAEL, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/