[PATCH v5 09/10] iommu/mediatek: Modify MMU_CTRL register setting

Chao Hao chao.hao at mediatek.com
Mon Jun 29 03:13:09 EDT 2020


MT8173 is different from other SoCs for MMU_CTRL register.
For mt8173, its bit9 is in_order_write_en and doesn't use its
default 1'b1.
For other SoCs, bit[12] represents victim_tlb_en feature and
victim_tlb is enable defaultly(bit[12]=1), if we use
"regval = F_MMU_TF_PROT_TO_PROGRAM_ADDR", victim_tlb will be
disabled, it will drop iommu performace.
So we need to deal with the setting of MMU_CTRL separately
for mt8173 and others.

Suggested-by: 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 | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 8299a3299090..e46e2deee3fd 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -543,11 +543,12 @@ static int mtk_iommu_hw_init(const struct mtk_iommu_data *data)
 		return ret;
 	}
 
+	regval = readl_relaxed(data->base + REG_MMU_CTRL_REG);
 	if (data->plat_data->m4u_plat == M4U_MT8173)
 		regval = F_MMU_PREFETCH_RT_REPLACE_MOD |
 			 F_MMU_TF_PROT_TO_PROGRAM_ADDR_MT8173;
 	else
-		regval = F_MMU_TF_PROT_TO_PROGRAM_ADDR;
+		regval |= F_MMU_TF_PROT_TO_PROGRAM_ADDR;
 	writel_relaxed(regval, data->base + REG_MMU_CTRL_REG);
 
 	regval = F_L2_MULIT_HIT_EN |
-- 
2.18.0


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