[PATCH v2 07/19] iommu/mediatek: Add REG_MMU_WR_LEN reg define prepare for mt6779

[Chao Hao]

When some platforms(ex:later mt6779) define has_wr_len variable,
we need to set REG_MMU_WR_LEN to improve performance. So we add
REG_MMU_WR_LEN register define in this patch.

Signed-off-by: Chao Hao <chao.hao@xxxxxxxxxxxx>
---
 drivers/iommu/mtk_iommu.c | 11 +++++++++++
 drivers/iommu/mtk_iommu.h |  2 ++
 2 files changed, 13 insertions(+)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 5de13ab1094e..ad5690350d6a 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -44,6 +44,8 @@
 
 #define REG_MMU_MISC_CTRL			0x048
 #define REG_MMU_DCM_DIS				0x050
+#define REG_MMU_WR_LEN				0x054
+#define F_MMU_WR_THROT_DIS			(BIT(5) |  BIT(21))
 
 #define REG_MMU_CTRL_REG			0x110
 #define F_MMU_TF_PROT_TO_PROGRAM_ADDR		(2 << 4)
@@ -595,6 +597,13 @@ static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
 	}
 	writel_relaxed(0, data->base + REG_MMU_DCM_DIS);
 
+	if (data->plat_data->has_wr_len) {
+		/* write command throttling mode */
+		regval = readl_relaxed(data->base + REG_MMU_WR_LEN);
+		regval &= ~F_MMU_WR_THROT_DIS;
+		writel_relaxed(regval, data->base + REG_MMU_WR_LEN);
+	}
+
 	if (data->plat_data->reset_axi)
 		writel_relaxed(0, data->base + REG_MMU_MISC_CTRL);
 
@@ -743,6 +752,7 @@ static int __maybe_unused mtk_iommu_suspend(struct device *dev)
 	struct mtk_iommu_suspend_reg *reg = &data->reg;
 	void __iomem *base = data->base;
 
+	reg->wr_len = readl_relaxed(base + REG_MMU_WR_LEN);
 	reg->standard_axi_mode = readl_relaxed(base +
 					       REG_MMU_MISC_CTRL);
 	reg->dcm_dis = readl_relaxed(base + REG_MMU_DCM_DIS);
@@ -768,6 +778,7 @@ static int __maybe_unused mtk_iommu_resume(struct device *dev)
 		dev_err(data->dev, "Failed to enable clk(%d) in resume\n", ret);
 		return ret;
 	}
+	writel_relaxed(reg->wr_len, base + REG_MMU_WR_LEN);
 	writel_relaxed(reg->standard_axi_mode,
 		       base + REG_MMU_MISC_CTRL);
 	writel_relaxed(reg->dcm_dis, base + REG_MMU_DCM_DIS);
diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
index d4495230c6e7..0623f199e96f 100644
--- a/drivers/iommu/mtk_iommu.h
+++ b/drivers/iommu/mtk_iommu.h
@@ -25,6 +25,7 @@ struct mtk_iommu_suspend_reg {
 	u32				int_main_control;
 	u32				ivrp_paddr;
 	u32				vld_pa_rng;
+	u32				wr_len;
 };
 
 enum mtk_iommu_plat {
@@ -43,6 +44,7 @@ struct mtk_iommu_plat_data {
 	bool                has_sub_comm[2];
 	bool                has_vld_pa_rng;
 	bool                reset_axi;
+	bool                has_wr_len;
 	u32                 m4u1_mask;
 	u32                 inv_sel_reg;
 	unsigned char       larbid_remap[2][MTK_LARB_NR_MAX];
-- 
2.18.0