On Tue, 2020-06-30 at 18:55 +0800, Yong Wu wrote: > 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 > ok, got it. Thanks for your advice. > > > > #define MTK_SMI_MMU_EN(port) BIT(port) > > > >