On Wed, 2020-06-17 at 11:34 +0200, Matthias Brugger wrote:

On 17/06/2020 05:00, Chao Hao wrote:

quoted

Add F_MMU_IN_ORDER_WR_EN definition in MISC_CTRL.
In order to improve performance, we always disable STANDARD_AXI_MODE
and IN_ORDER_WR_EN in MISC_CTRL.

Change since v3:

The changelog should go below the '---' as we don't want this in the git history
once the patch get's accepted.

okok, thanks

quoted

1. Rename Disable STANDARD_AXI_MODE in MISC_CTRL to Set MISC_CTRL register
2. Add F_MMU_IN_DRDER_WR_EN definition in MISC_CTRL
       We need to disable in_order_write to improve performance

Cc: Yong Wu <yong.wu@mediatek.com>
Signed-off-by: Chao Hao <redacted>
---
 drivers/iommu/mtk_iommu.c | 11 +++++++++++
 drivers/iommu/mtk_iommu.h |  1 +
 2 files changed, 12 insertions(+)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 88d3df5b91c2..239d2cdbbc9f 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c

@@ -42,6 +42,9 @@
 #define F_INVLD_EN1				BIT(1)
 
 #define REG_MMU_MISC_CTRL			0x048
+#define F_MMU_IN_ORDER_WR_EN			(BIT(1) | BIT(17))
+#define F_MMU_STANDARD_AXI_MODE_BIT		(BIT(3) | BIT(19))
+
 #define REG_MMU_DCM_DIS				0x050
 
 #define REG_MMU_CTRL_REG			0x110

@@ -578,6 +581,14 @@ static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
 		writel_relaxed(0, data->base + REG_MMU_MISC_CTRL);
 	}
 
+	if (data->plat_data->has_misc_ctrl) {

That's confusing. We renamed the register to misc_ctrl, but it's present in all
SoCs. We should find a better name for this flag to describe what the hardware
supports.

ok, thanks for you advice, I will rename it in next version.
ex:has_perf_req(has performance requirement)

Regards,
Matthias

quoted

+		/* For mm_iommu, it can improve performance by the setting */
+		regval = readl_relaxed(data->base + REG_MMU_MISC_CTRL);
+		regval &= ~F_MMU_STANDARD_AXI_MODE_BIT;
+		regval &= ~F_MMU_IN_ORDER_WR_EN;
+		writel_relaxed(regval, data->base + REG_MMU_MISC_CTRL);
+	}
+
 	if (devm_request_irq(data->dev, data->irq, mtk_iommu_isr, 0,
 			     dev_name(data->dev), (void *)data)) {
 		writel_relaxed(0, data->base + REG_MMU_PT_BASE_ADDR);

diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
index 1b6ea839b92c..d711ac630037 100644
--- a/drivers/iommu/mtk_iommu.h
+++ b/drivers/iommu/mtk_iommu.h

@@ -40,6 +40,7 @@ struct mtk_iommu_plat_data {
 
 	/* HW will use the EMI clock if there isn't the "bclk". */
 	bool                has_bclk;
+	bool		    has_misc_ctrl;
 	bool                has_vld_pa_rng;
 	bool                reset_axi;
 	unsigned char       larbid_remap[MTK_LARB_NR_MAX];

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