On Mon, 2020-06-29 at 15:13 +0800, Chao Hao wrote:
> The max larb number that a iommu HW support is 8(larb0~larb7 in the below
> diagram).
> If the larb's number is over 8, we use a sub_common for merging
> several larbs into one larb. At this case, we will extend larb_id:
> bit[11:9] means common-id;
> bit[8:7] means subcommon-id;
> From these two variables, we could get the real larb number when
> translation fault happen.
> The diagram is as below:
> EMI
> |
> IOMMU
> |
> -----------------
> | |
> common1 common0
> | |
> -----------------
> |
> smi common
> |
> ------------------------------------
> | | | | | |
> 3'd0 3'd1 3'd2 3'd3 ... 3'd7 <-common_id(max is 8)
> | | | | | |
> Larb0 Larb1 | Larb3 ... Larb7
> |
> smi sub common
> |
> --------------------------
> | | | |
> 2'd0 2'd1 2'd2 2'd3 <-sub_common_id(max is 4)
> | | | |
> Larb8 Larb9 Larb10 Larb11
>
> In this patch we extend larb_remap[] to larb_remap[8][4] for this.
> larb_remap[x][y]: x means common-id above, y means subcommon_id above.
>
> We can also distinguish if the M4U HW has sub_common by HAS_SUB_COMM
> macro.
>
> Cc: Matthias Brugger <matthias.bgg@xxxxxxxxx>
> Signed-off-by: Chao Hao <chao.hao@xxxxxxxxxxxx>
> Reviewed-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
> ---
> drivers/iommu/mtk_iommu.c | 20 +++++++++++++-------
> drivers/iommu/mtk_iommu.h | 3 ++-
> include/soc/mediatek/smi.h | 2 ++
> 3 files changed, 17 insertions(+), 8 deletions(-)
[snip]
> @@ -48,7 +49,7 @@ struct mtk_iommu_plat_data {
> enum mtk_iommu_plat m4u_plat;
> u32 flags;
> u32 inv_sel_reg;
> - unsigned char larbid_remap[MTK_LARB_NR_MAX];
> + unsigned char larbid_remap[MTK_LARB_COM_MAX][MTK_LARB_SUBCOM_MAX];
> };
>
> struct mtk_iommu_domain;
> diff --git a/include/soc/mediatek/smi.h b/include/soc/mediatek/smi.h
> index 5a34b87d89e3..fa65a55468e2 100644
> --- a/include/soc/mediatek/smi.h
> +++ b/include/soc/mediatek/smi.h
> @@ -12,6 +12,8 @@
> #ifdef CONFIG_MTK_SMI
>
> #define MTK_LARB_NR_MAX 16
> +#define MTK_LARB_COM_MAX 8
> +#define MTK_LARB_SUBCOM_MAX 4
Both are only used in mtk_iommu.h, and I don't think smi has plan to use
them. thus we could move them into mtk_iommu.h
>
> #define MTK_SMI_MMU_EN(port) BIT(port)
>
