[PATCH v6 4/4] iommu: rockchip: Add support for iommu v2

[Benjamin Gaignard]

This second version of the hardware block has a different bits
mapping for page table entries.
Add the ops matching to this new mapping.
Define a new compatible to distinguish it from the first version.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard at collabora.com>
Reviewed-by: Heiko Stuebner <heiko at sntech.de>
---
version 5:
 - Use internal ops to support v2 hardware block
 - Use GENMASK macro.
 - Keep rk_dte_pt_address() and rk_dte_pt_address_v2() separated
   because I believe that is more readable like this.
 - Do not duplicate code.

 drivers/iommu/rockchip-iommu.c | 78 ++++++++++++++++++++++++++++++++++
 1 file changed, 78 insertions(+)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index 7b537dd168ca..d943b9d8bdb2 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -187,6 +187,33 @@ static inline phys_addr_t rk_dte_pt_address(u32 dte)
 	return (phys_addr_t)dte & RK_DTE_PT_ADDRESS_MASK;
 }
 
+/*
+ * In v2:
+ * 31:12 - PT address bit 31:0
+ * 11: 8 - PT address bit 35:32
+ *  7: 4 - PT address bit 39:36
+ *  3: 1 - Reserved
+ *     0 - 1 if PT @ PT address is valid
+ */
+#define RK_DTE_PT_ADDRESS_MASK_V2 GENMASK_ULL(31, 4)
+#define DTE_HI_MASK1	GENMASK(11, 8)
+#define DTE_HI_MASK2	GENMASK(7, 4)
+#define DTE_HI_SHIFT1	24 /* shift bit 8 to bit 32 */
+#define DTE_HI_SHIFT2	32 /* shift bit 4 to bit 36 */
+#define PAGE_DESC_HI_MASK1	GENMASK_ULL(39, 36)
+#define PAGE_DESC_HI_MASK2	GENMASK_ULL(35, 32)
+
+static inline phys_addr_t rk_dte_pt_address_v2(u32 dte)
+{
+	u64 dte_v2 = dte;
+
+	dte_v2 = ((dte_v2 & DTE_HI_MASK2) << DTE_HI_SHIFT2) |
+		 ((dte_v2 & DTE_HI_MASK1) << DTE_HI_SHIFT1) |
+		 (dte_v2 & RK_DTE_PT_ADDRESS_MASK);
+
+	return (phys_addr_t)dte_v2;
+}
+
 static inline bool rk_dte_is_pt_valid(u32 dte)
 {
 	return dte & RK_DTE_PT_VALID;
@@ -197,6 +224,15 @@ static inline u32 rk_mk_dte(dma_addr_t pt_dma)
 	return (pt_dma & RK_DTE_PT_ADDRESS_MASK) | RK_DTE_PT_VALID;
 }
 
+static inline u32 rk_mk_dte_v2(dma_addr_t pt_dma)
+{
+	pt_dma = (pt_dma & RK_DTE_PT_ADDRESS_MASK) |
+		 ((pt_dma & PAGE_DESC_HI_MASK1) >> DTE_HI_SHIFT1) |
+		 (pt_dma & PAGE_DESC_HI_MASK2) >> DTE_HI_SHIFT2;
+
+	return (pt_dma & RK_DTE_PT_ADDRESS_MASK_V2) | RK_DTE_PT_VALID;
+}
+
 /*
  * Each PTE has a Page address, some flags and a valid bit:
  * +---------------------+---+-------+-+
@@ -238,6 +274,29 @@ static u32 rk_mk_pte(phys_addr_t page, int prot)
 	return page | flags | RK_PTE_PAGE_VALID;
 }
 
+/*
+ * In v2:
+ * 31:12 - Page address bit 31:0
+ *  11:9 - Page address bit 34:32
+ *   8:4 - Page address bit 39:35
+ *     3 - Security
+ *     2 - Readable
+ *     1 - Writable
+ *     0 - 1 if Page @ Page address is valid
+ */
+#define RK_PTE_PAGE_READABLE_V2      BIT(2)
+#define RK_PTE_PAGE_WRITABLE_V2      BIT(1)
+
+static u32 rk_mk_pte_v2(phys_addr_t page, int prot)
+{
+	u32 flags = 0;
+
+	flags |= (prot & IOMMU_READ) ? RK_PTE_PAGE_READABLE_V2 : 0;
+	flags |= (prot & IOMMU_WRITE) ? RK_PTE_PAGE_WRITABLE_V2 : 0;
+
+	return rk_mk_dte_v2(page) | flags;
+}
+
 static u32 rk_mk_pte_invalid(u32 pte)
 {
 	return pte & ~RK_PTE_PAGE_VALID;
@@ -478,6 +537,15 @@ static inline phys_addr_t rk_dte_addr_phys(u32 addr)
 	return (phys_addr_t)addr;
 }
 
+#define DT_HI_MASK GENMASK_ULL(39, 32)
+#define DT_SHIFT   28
+
+static inline phys_addr_t rk_dte_addr_phys_v2(u32 addr)
+{
+	return (phys_addr_t)(addr & RK_DTE_PT_ADDRESS_MASK) |
+	       ((addr & DT_HI_MASK) << DT_SHIFT);
+}
+
 static void log_iova(struct rk_iommu *iommu, int index, dma_addr_t iova)
 {
 	void __iomem *base = iommu->bases[index];
@@ -1305,10 +1373,20 @@ static struct rk_iommu_ops iommu_data_ops_v1 = {
 	.dte_addr_phys = &rk_dte_addr_phys,
 };
 
+static struct rk_iommu_ops iommu_data_ops_v2 = {
+	.pt_address = &rk_dte_pt_address_v2,
+	.mk_dtentries = &rk_mk_dte_v2,
+	.mk_ptentries = &rk_mk_pte_v2,
+	.dte_addr_phys = &rk_dte_addr_phys_v2,
+};
+
 static const struct of_device_id rk_iommu_dt_ids[] = {
 	{	.compatible = "rockchip,iommu",
 		.data = &iommu_data_ops_v1,
 	},
+	{	.compatible = "rockchip,rk3568-iommu",
+		.data = &iommu_data_ops_v2,
+	},
 	{ /* sentinel */ }
 };
 
-- 
2.25.1