On Fri, 2017-08-11 at 16:39 +0530, Arvind Yadav wrote:

Hi Youn,


On Friday 11 August 2017 03:26 PM, Yong Wu wrote:

quoted

When system suspend, infra power domain may be off, and the iommu's
clock must be disabled when system off, or the iommu's bclk clock maybe
disabled after system resume.

Signed-off-by: Honghui Zhang <redacted>
Signed-off-by: Yong Wu <yong.wu@mediatek.com>
---
  drivers/iommu/mtk_iommu.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index e81ed9a..b7c8e52 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c

@@ -675,6 +675,7 @@ static int __maybe_unused mtk_iommu_suspend(struct device *dev)
  	reg->ctrl_reg = readl_relaxed(base + REG_MMU_CTRL_REG);
  	reg->int_control0 = readl_relaxed(base + REG_MMU_INT_CONTROL0);
  	reg->int_main_control = readl_relaxed(base + REG_MMU_INT_MAIN_CONTROL);
+	clk_disable_unprepare(data->bclk);
  	return 0;
  }
  

@@ -684,6 +685,7 @@ static int __maybe_unused mtk_iommu_resume(struct device *dev)
  	struct mtk_iommu_suspend_reg *reg = &data->reg;
  	void __iomem *base = data->base;
  
+	clk_prepare_enable(data->bclk);

Please handle return value of clk_prepare_enable. It can fail

Thanks for the reminding. I will add it in next version.

quoted

  	writel_relaxed(reg->standard_axi_mode,
  		       base + REG_MMU_STANDARD_AXI_MODE);
  	writel_relaxed(reg->dcm_dis, base + REG_MMU_DCM_DIS);

@@ -699,7 +701,7 @@ static int __maybe_unused mtk_iommu_resume(struct device *dev)
  }
  
  static const struct dev_pm_ops mtk_iommu_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(mtk_iommu_suspend, mtk_iommu_resume)
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_iommu_suspend, mtk_iommu_resume)
  };
  
  static const struct of_device_id mtk_iommu_of_ids[] = {

~arvind