[PATCH v5 04/10] iommu/mediatek: Setting MISC_CTRL register

[Chao Hao]

Add F_MMU_IN_ORDER_WR_EN and F_MMU_STANDARD_AXI_MODE_BIT definition
in MISC_CTRL register.
F_MMU_STANDARD_AXI_MODE_BIT:
  If we set F_MMU_STANDARD_AXI_MODE_BIT(bit[3][19] = 0, not follow
standard AXI protocol), iommu will send urgent read command firstly
compare with normal read command to improve performance.
F_MMU_IN_ORDER_WR_EN:
  If we set F_MMU_IN_ORDER_WR_EN(bit[1][17] = 0, out-of-order write), iommu
will re-order write command and send more higher priority write command
instead of sending write command in order. The feature be controlled
by OUT_ORDER_EN macro definition.

Cc: Matthias Brugger <matthias.bgg at gmail.com>
Suggested-by: Yong Wu <yong.wu at mediatek.com>
Signed-off-by: Chao Hao <chao.hao at mediatek.com>
---
 drivers/iommu/mtk_iommu.c | 12 +++++++++++-
 drivers/iommu/mtk_iommu.h |  1 +
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 8f81df6cbe51..67b46b5d83d9 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
@@ -574,10 +577,17 @@ static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
 	}
 	writel_relaxed(0, data->base + REG_MMU_DCM_DIS);
 
+	regval = readl_relaxed(data->base + REG_MMU_MISC_CTRL);
 	if (MTK_IOMMU_HAS_FLAG(data->plat_data, RESET_AXI)) {
 		/* The register is called STANDARD_AXI_MODE in this case */
-		writel_relaxed(0, data->base + REG_MMU_MISC_CTRL);
+		regval = 0;
+	} else {
+		/* For mm_iommu, it can improve performance by the setting */
+		regval &= ~F_MMU_STANDARD_AXI_MODE_BIT;
+		if (MTK_IOMMU_HAS_FLAG(data->plat_data, OUT_ORDER_EN))
+			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)) {
diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
index 7cc39f729263..4b780b651ef4 100644
--- a/drivers/iommu/mtk_iommu.h
+++ b/drivers/iommu/mtk_iommu.h
@@ -22,6 +22,7 @@
 #define HAS_BCLK			BIT(1)
 #define HAS_VLD_PA_RNG			BIT(2)
 #define RESET_AXI			BIT(3)
+#define OUT_ORDER_EN			BIT(4)
 
 #define MTK_IOMMU_HAS_FLAG(pdata, _x) \
 		((((pdata)->flags) & (_x)) == (_x))
-- 
2.18.0