[PATCH v4 08/18] iommu/mediatek: Add larb-id remapped support

[Yong Wu <yong.wu-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>]

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-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>
---
 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];
 };
 
 struct mtk_iommu_domain;
-- 
1.9.1