[PATCH 1/4] iommu/mediatek: Initialise the secure bank

From: Yong Wu
Date: Sun Sep 10 2023 - 21:18:24 EST


The lastest IOMMU always have 5 banks, and we always use the last bank
(id:4) for the secure memory address translation. This patch add a new
flag (SECURE_BANK_ENABLE) for this feature.

For the secure bank, its kernel va "base" is not helpful since the
secure bank registers has already been protected and can only be accessed
in the secure world. But we still record its register base, because we need
use it to determine which IOMMU HW the translation fault happen in the
secure world.

Signed-off-by: Anan Sun <anan.sun@xxxxxxxxxxxx>
Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
---
drivers/iommu/mtk_iommu.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 640275873a27..4a2cffb28c61 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -146,6 +146,7 @@
#define TF_PORT_TO_ADDR_MT8173 BIT(18)
#define INT_ID_PORT_WIDTH_6 BIT(19)
#define CFG_IFA_MASTER_IN_ATF BIT(20)
+#define SECURE_BANK_ENABLE BIT(21)

#define MTK_IOMMU_HAS_FLAG_MASK(pdata, _x, mask) \
((((pdata)->flags) & (mask)) == (_x))
@@ -162,6 +163,8 @@
#define MTK_IOMMU_GROUP_MAX 8
#define MTK_IOMMU_BANK_MAX 5

+#define MTK_IOMMU_SEC_BANKID 4
+
enum mtk_iommu_plat {
M4U_MT2712,
M4U_MT6779,
@@ -240,9 +243,13 @@ struct mtk_iommu_plat_data {
};

struct mtk_iommu_bank_data {
- void __iomem *base;
+ union {
+ void __iomem *base;
+ phys_addr_t sec_bank_base;
+ };
int irq;
u8 id;
+ bool is_secure;
struct device *parent_dev;
struct mtk_iommu_data *parent_data;
spinlock_t tlb_lock; /* lock for tlb range flush */
@@ -1309,7 +1316,15 @@ static int mtk_iommu_probe(struct platform_device *pdev)
continue;
bank = &data->bank[i];
bank->id = i;
- bank->base = base + i * MTK_IOMMU_BANK_SZ;
+ if (MTK_IOMMU_HAS_FLAG(data->plat_data, SECURE_BANK_ENABLE) &&
+ bank->id == MTK_IOMMU_SEC_BANKID) {
+ /* Record the secure bank base to indicate which iommu TF in sec world */
+ bank->sec_bank_base = res->start + i * MTK_IOMMU_BANK_SZ;
+ bank->is_secure = true;
+ } else {
+ bank->base = base + i * MTK_IOMMU_BANK_SZ;
+ bank->is_secure = false;
+ }
bank->m4u_dom = NULL;

bank->irq = platform_get_irq(pdev, i);
--
2.25.1