From d75f7fe495cf57501c83b8ea5d0d799d2c2ff841 Mon Sep 17 00:00:00 2001 From: Yaniv Gardi Date: Mon, 1 Feb 2016 15:02:47 +0200 Subject: [PATCH] scsi: ufs: reduce the interrupts for power mode change requests 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. Reviewed-by: Gilad Broner Reviewed-by: Dolev Raviv Signed-off-by: Subhash Jadavani Signed-off-by: Yaniv Gardi Signed-off-by: Martin K. Petersen --- 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 87da429ab7eb..a1e9d82716a6 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -985,13 +985,15 @@ 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, @@ -999,7 +1001,8 @@ __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); @@ -1024,7 +1027,7 @@ 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); @@ -2344,6 +2347,7 @@ 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); @@ -2351,15 +2355,17 @@ 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", @@ -2385,7 +2391,10 @@ 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); @@ -3810,16 +3819,20 @@ 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); -- 2.20.1