On 03/07/2020 06:41, Chao Hao wrote: > Add F_MMU_IN_ORDER_WR_EN_MASK and F_MMU_STANDARD_AXI_MODE_EN_MASK > definitions in MISC_CTRL register. > F_MMU_STANDARD_AXI_MODE_EN_MASK: > If we set F_MMU_STANDARD_AXI_MODE_EN_MASK (bit[3][19] = 0, not follow > standard AXI protocol), the iommu will priorize sending of urgent read > command over a normal read command. This improves the performance. > F_MMU_IN_ORDER_WR_EN_MASK: > If we set F_MMU_IN_ORDER_WR_EN_MASK (bit[1][17] = 0, out-of-order write), > the iommu will re-order write commands and send the write commands with > higher priority. Otherwise the sending of write commands will be done in > order. The feature is controlled by OUT_ORDER_WR_EN platform data flag. > > Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx> > Suggested-by: Yong Wu <yong.wu@xxxxxxxxxxxx> > Signed-off-by: Chao Hao <chao.hao@xxxxxxxxxxxx> Reviewed-by: Matthias Brugger <matthias.bgg@xxxxxxxxx> > --- > drivers/iommu/mtk_iommu.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c > index 40ca564d97af..219d7aa6f059 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_MASK (BIT(1) | BIT(17)) > +#define F_MMU_STANDARD_AXI_MODE_MASK (BIT(3) | BIT(19)) > + > #define REG_MMU_DCM_DIS 0x050 > > #define REG_MMU_CTRL_REG 0x110 > @@ -105,6 +108,7 @@ > #define HAS_BCLK BIT(1) > #define HAS_VLD_PA_RNG BIT(2) > #define RESET_AXI BIT(3) > +#define OUT_ORDER_WR_EN BIT(4) > > #define MTK_IOMMU_HAS_FLAG(pdata, _x) \ > ((((pdata)->flags) & (_x)) == (_x)) > @@ -585,8 +589,14 @@ static int mtk_iommu_hw_init(const struct mtk_iommu_data *data) > > 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 { > + regval = readl_relaxed(data->base + REG_MMU_MISC_CTRL); > + regval &= ~F_MMU_STANDARD_AXI_MODE_MASK; > + if (MTK_IOMMU_HAS_FLAG(data->plat_data, OUT_ORDER_WR_EN)) > + regval &= ~F_MMU_IN_ORDER_WR_EN_MASK; > } > + 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)) { >