Hi Nicolas,

Thanks for the review of this patchset.

On Fri, 2018-12-21 at 11:35 +0800, Nicolas Boichat wrote:

On Sat, Dec 8, 2018 at 4:42 PM Yong Wu [off-list ref] wrote:

quoted

The larb-id may be remapped in the smi-common, this means the
larb-id reported in the mtk_iommu_isr isn't the real larb-id,

Take mt8183 as a example:
                       M4U
                        |
---------------------------------------------
|               SMI common                  |
-0-----7-----5-----6-----1-----2------3-----4- <- Id remapped
 |     |     |     |     |     |      |     |
larb0 larb1 IPU0  IPU1 larb4 larb5  larb6  CCU
disp  vdec  img   cam   venc  img    cam
As above, larb0 connects with the id 0 in smi-common.
          larb1 connects with the id 7 in smi-common.
          ...
If the larb-id reported in the isr is 7, actually it's larb1(vdec).
In order to output the right larb-id in the isr, we add a larb-id
remapping relationship in this patch.

This also is a preparing patch for mt8183.

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
---
 drivers/iommu/mtk_iommu.c | 3 +++
 drivers/iommu/mtk_iommu.h | 4 ++++
 2 files changed, 7 insertions(+)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index eda062a..8ab3b69 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c

@@ -220,6 +220,9 @@ static irqreturn_t mtk_iommu_isr(int irq, void *dev_id)
        fault_larb = F_MMU0_INT_ID_LARB_ID(regval);
        fault_port = F_MMU0_INT_ID_PORT_ID(regval);

+       if (data->plat_data->larbid_remap_enable)
+               fault_larb = data->plat_data->larbid_remapped[fault_larb];
+
        if (report_iommu_fault(&dom->domain, data->dev, fault_iova,
                               write ? IOMMU_FAULT_WRITE : IOMMU_FAULT_READ)) {
                dev_err_ratelimited(

diff --git a/drivers/iommu/mtk_iommu.h b/drivers/iommu/mtk_iommu.h
index b8749ac..3877050 100644
--- a/drivers/iommu/mtk_iommu.h
+++ b/drivers/iommu/mtk_iommu.h

@@ -47,6 +47,10 @@ struct mtk_iommu_plat_data {

        /* HW will use the EMI clock if there isn't the "bclk". */
        bool                has_bclk;
+
+       /* The larb-id may be remapped in the smi-common. */
+       bool                larbid_remap_enable;
+       unsigned int        larbid_remapped[MTK_LARB_NR_MAX];

Wouldn't it be a little simpler if you just had
larbid_remap[MTK_LARB_NR_MAX] (no larbid_remap_enable), and just set
it to {0, 1, 2, 3, 4, 5, 6, 7} in platforms that don't need
complicated remapping?

Actually I'd like the original way(Print the larb-id from the register
directly if larb-id is not remapped). But this solution is also ok for
me.

Also, unsigned char/u8 array would be enough.

OK. "unsigned char" is enough.
Originally I think "int" or "long" may be better to access in ARM/ARM64.

quoted

 };

 struct mtk_iommu_domain;
--
1.9.1

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