From 2eb5b31ac1e3398173e2bf5a042f638056b9fd7f Mon Sep 17 00:00:00 2001 From: Peter Wang Date: Thu, 31 Aug 2023 21:08:25 +0800 Subject: [PATCH] FROMLIST: ufs: core: fix abnormal scale up after last cmd finish When ufshcd_clk_scaling_suspend_work(Thread A) running and new command coming, ufshcd_clk_scaling_start_busy(Thread B) may get host_lock after Thread A first time release host_lock. Then Thread A second time get host_lock will set clk_scaling.window_start_t = 0 which scale up clock abnormal next polling_ms time. Also inlines another __ufshcd_suspend_clkscaling calls. Below is racing step: 1 hba->clk_scaling.suspend_work (Thread A) ufshcd_clk_scaling_suspend_work 2 spin_lock_irqsave(hba->host->host_lock, irq_flags); 3 hba->clk_scaling.is_suspended = true; 4 spin_unlock_irqrestore(hba->host->host_lock, irq_flags); __ufshcd_suspend_clkscaling 7 spin_lock_irqsave(hba->host->host_lock, flags); 8 hba->clk_scaling.window_start_t = 0; 9 spin_unlock_irqrestore(hba->host->host_lock, flags); ufshcd_send_command (Thread B) ufshcd_clk_scaling_start_busy 5 spin_lock_irqsave(hba->host->host_lock, flags); .... 6 spin_unlock_irqrestore(hba->host->host_lock, flags); Bug: 298004596 Link: https://lore.kernel.org/all/20230831130826.5592-3-peter.wang@mediatek.com/ Change-Id: Ib208b1265107769005c4ae3f72d46b12c072b5c7 Signed-off-by: Peter Wang --- drivers/ufs/core/ufshcd.c | 17 ++++------------- 1 file changed, 4 insertions(+), 13 deletions(-) diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c index 3ff3301f5262..430ae3d2fc8a 100644 --- a/drivers/ufs/core/ufshcd.c +++ b/drivers/ufs/core/ufshcd.c @@ -294,7 +294,6 @@ static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba); static int ufshcd_host_reset_and_restore(struct ufs_hba *hba); static void ufshcd_resume_clkscaling(struct ufs_hba *hba); static void ufshcd_suspend_clkscaling(struct ufs_hba *hba); -static void __ufshcd_suspend_clkscaling(struct ufs_hba *hba); 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, @@ -1417,9 +1416,10 @@ static void ufshcd_clk_scaling_suspend_work(struct work_struct *work) return; } hba->clk_scaling.is_suspended = true; + hba->clk_scaling.window_start_t = 0; spin_unlock_irqrestore(hba->host->host_lock, irq_flags); - __ufshcd_suspend_clkscaling(hba); + devfreq_suspend_device(hba->devfreq); } static void ufshcd_clk_scaling_resume_work(struct work_struct *work) @@ -1608,16 +1608,6 @@ static void ufshcd_devfreq_remove(struct ufs_hba *hba) dev_pm_opp_remove(hba->dev, clki->max_freq); } -static void __ufshcd_suspend_clkscaling(struct ufs_hba *hba) -{ - unsigned long flags; - - devfreq_suspend_device(hba->devfreq); - spin_lock_irqsave(hba->host->host_lock, flags); - hba->clk_scaling.window_start_t = 0; - spin_unlock_irqrestore(hba->host->host_lock, flags); -} - static void ufshcd_suspend_clkscaling(struct ufs_hba *hba) { unsigned long flags; @@ -1630,11 +1620,12 @@ static void ufshcd_suspend_clkscaling(struct ufs_hba *hba) if (!hba->clk_scaling.is_suspended) { suspend = true; hba->clk_scaling.is_suspended = true; + hba->clk_scaling.window_start_t = 0; } spin_unlock_irqrestore(hba->host->host_lock, flags); if (suspend) - __ufshcd_suspend_clkscaling(hba); + devfreq_suspend_device(hba->devfreq); } static void ufshcd_resume_clkscaling(struct ufs_hba *hba)