Re: [PATCH v4 7/7] iommu/mediatek: Add mt6779 basic support

[Matthias Brugger]

On 17/06/2020 05:00, Chao Hao wrote:
> 1. Start from mt6779, INVLDT_SEL move to offset=0x2c, so we add
>    REG_MMU_INV_SEL_GEN2 definition and mt6779 uses it.
> 2. Change PROTECT_PA_ALIGN from 128 byte to 256 byte.
> 3. For REG_MMU_CTRL_REG register, we only need to change bit[2:0],
>    others bits keep default value, ex: enable victim tlb.
> 4. Add mt6779_data to support mm_iommu HW init.
> 
> Change since v3:
> 1. When setting MMU_CTRL_REG, we don't need to include mt8173.
> 
> Cc: Yong Wu <yong.wu@xxxxxxxxxxxx>
> Signed-off-by: Chao Hao <chao.hao@xxxxxxxxxxxx>
> ---
>  drivers/iommu/mtk_iommu.c | 20 ++++++++++++++++++--
>  drivers/iommu/mtk_iommu.h |  1 +
>  2 files changed, 19 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
> index c706bca6487e..def2e996683f 100644
> --- a/drivers/iommu/mtk_iommu.c
> +++ b/drivers/iommu/mtk_iommu.c
> @@ -37,6 +37,11 @@
>  #define REG_MMU_INVLD_START_A			0x024
>  #define REG_MMU_INVLD_END_A			0x028
>  
> +/* In latest Coda, MMU_INV_SEL's offset is changed to 0x02c.
> + * So we named offset = 0x02c to "REG_MMU_INV_SEL_GEN2"
> + * and offset = 0x038 to "REG_MMU_INV_SEL_GEN1".
> + */

Please delete the comment, this should be understandable from the git history

> +#define REG_MMU_INV_SEL_GEN2			0x02c
>  #define REG_MMU_INV_SEL_GEN1			0x038
>  #define F_INVLD_EN0				BIT(0)
>  #define F_INVLD_EN1				BIT(1)
> @@ -98,7 +103,7 @@
>  #define F_MMU_INT_ID_LARB_ID(a)			(((a) >> 7) & 0x7)
>  #define F_MMU_INT_ID_PORT_ID(a)			(((a) >> 2) & 0x1f)
>  
> -#define MTK_PROTECT_PA_ALIGN			128
> +#define MTK_PROTECT_PA_ALIGN			256

Do we need 512 bytes for all gen2 IOMMUs?
I'm not sure if we should add this in plat_data or if we should just bump up the
value for all SoCs.
In both cases this should be a separate patch.

>  
>  /*
>   * Get the local arbiter ID and the portid within the larb arbiter
> @@ -543,11 +548,12 @@ 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;

Why do we change this, is it that the bootloader for mt6779 set some values in
the register we have to keep? In this case I think we should update the regval
accordingly.

>  	writel_relaxed(regval, data->base + REG_MMU_CTRL_REG);
>  
>  	regval = F_L2_MULIT_HIT_EN |
> @@ -797,6 +803,15 @@ static const struct mtk_iommu_plat_data mt2712_data = {
>  	.larbid_remap   = {{0}, {1}, {2}, {3}, {4}, {5}, {6}, {7}},
>  };
>  
> +static const struct mtk_iommu_plat_data mt6779_data = {
> +	.m4u_plat      = M4U_MT6779,
> +	.has_sub_comm  = true,
> +	.has_wr_len    = true,
> +	.has_misc_ctrl = true,
> +	.inv_sel_reg   = REG_MMU_INV_SEL_GEN2,
> +	.larbid_remap  = {{0}, {1}, {2}, {3}, {5}, {7, 8}, {10}, {9}},
> +};
> +
>  static const struct mtk_iommu_plat_data mt8173_data = {
>  	.m4u_plat     = M4U_MT8173,
>  	.has_4gb_mode = true,
> @@ -815,6 +830,7 @@ static const struct mtk_iommu_plat_data mt8183_data = {
>  
>  static const struct of_device_id mtk_iommu_of_ids[] = {
>  	{ .compatible = "mediatek,mt2712-m4u", .data = &mt2712_data},
> +	{ .compatible = "mediatek,mt6779-m4u", .data = &mt6779_data},
>  	{ .compatible = "mediatek,mt8173-m4u", .data = &mt8173_data},
>  	{ .compatible = "mediatek,mt8183-m4u", .data = &mt8183_data},
>  	{}
> diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
> index 9971cedd72ea..fb79e710c8d9 100644
> --- a/drivers/iommu/mtk_iommu.h
> +++ b/drivers/iommu/mtk_iommu.h
> @@ -31,6 +31,7 @@ struct mtk_iommu_suspend_reg {
>  enum mtk_iommu_plat {
>  	M4U_MT2701,
>  	M4U_MT2712,
> +	M4U_MT6779,
>  	M4U_MT8173,
>  	M4U_MT8183,
>  };
>