[PATCH v8 03/25] iommu/arm-smmu-v3: Introduce RangeInval encoding helpers

[Mostafa Saleh]

Move some of the RIL encodings into helpers so the hypervisor can
reuse them.
The hypervisor is going to have its own algorithm to determine the
sequence of RIL commands needed.

Signed-off-by: Mostafa Saleh <smostafa at google.com>
---
I removed the refactoring from this patch as this code would be
deleted anyway.
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 14 +++-------
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 30 +++++++++++++++++++++
 2 files changed, 34 insertions(+), 10 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index df1924969212..2e54d1ba2566 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2418,8 +2418,7 @@ static void arm_smmu_cmdq_batch_add_range(struct arm_smmu_device *smmu,
 	if (smmu->features & ARM_SMMU_FEAT_RANGE_INV) {
 		num_pages = size >> tg;
 
-		/* Convert page size of 12,14,16 (log2) to 1,2,3 */
-		tg_enc = (tg - 10) / 2;
+		tg_enc = arm_smmu_tlb_inv_tg_enc(tg);
 
 		/*
 		 * Determine what level the granule is at. For non-leaf, both
@@ -2430,7 +2429,7 @@ static void arm_smmu_cmdq_batch_add_range(struct arm_smmu_device *smmu,
 		 * where both scale and num could be 0 as well.
 		 */
 		if (leaf)
-			ttl = 4 - ((ilog2(granule) - 3) / (tg - 3));
+			ttl = arm_smmu_tlb_inv_ttl(granule, tg);
 		else if ((num_pages & CMDQ_TLBI_RANGE_NUM_MAX) == 1)
 			num_pages++;
 	}
@@ -2452,10 +2451,8 @@ static void arm_smmu_cmdq_batch_add_range(struct arm_smmu_device *smmu,
 			/* Determine how many chunks of 2^scale size we have */
 			num = (num_pages >> scale) & CMDQ_TLBI_RANGE_NUM_MAX;
 
-			/* Keep the pre-DS 5-bit truncation when scale > 31 */
 			cmd->data[0] = orig_data0 |
-				FIELD_PREP(CMDQ_TLBI_0_NUM, num - 1) |
-				FIELD_PREP(CMDQ_TLBI_0_SCALE, scale & 0x1f);
+				arm_smmu_tlb_inv_range_enc(num, scale);
 
 			/* range is num * 2^scale * pgsize */
 			inv_range = num << (scale + tg);
@@ -2469,10 +2466,7 @@ static void arm_smmu_cmdq_batch_add_range(struct arm_smmu_device *smmu,
 		 * command and something would be very broken if iova had them
 		 * set.
 		 */
-		cmd->data[1] = FIELD_PREP(CMDQ_TLBI_1_LEAF, leaf) |
-			       FIELD_PREP(CMDQ_TLBI_1_TTL, ttl) |
-			       FIELD_PREP(CMDQ_TLBI_1_TG, tg_enc) |
-			       (iova & ~GENMASK_U64(11, 0));
+		cmd->data[1] = arm_smmu_tlb_inv_addr(iova, leaf, ttl, tg_enc);
 
 		arm_smmu_cmdq_batch_add_cmd_p(smmu, cmds, cmd);
 		iova += inv_range;
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 5b23f6ee78d4..f3e80d103ba1 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -1285,6 +1285,36 @@ static inline void arm_smmu_write_strtab_l1_desc(struct arm_smmu_strtab_l1 *dst,
 	WRITE_ONCE(dst->l2ptr, cpu_to_le64(val));
 }
 
+/* Convert page size of 12,14,16 (log2) to 1,2,3 */
+static inline u8 arm_smmu_tlb_inv_tg_enc(size_t tg)
+{
+	return (tg - 10) / 2;
+}
+
+/* Only valid for leaf invalidations, non-leaf must use TTL=0 */
+static inline u8 arm_smmu_tlb_inv_ttl(size_t granule, size_t tg)
+{
+	return 4 - ((ilog2(granule) - 3) / (tg - 3));
+}
+
+static inline u64 arm_smmu_tlb_inv_addr(unsigned long iova, bool leaf, u8 ttl, u8 tg_enc)
+{
+	return FIELD_PREP(CMDQ_TLBI_1_LEAF, leaf) |
+		FIELD_PREP(CMDQ_TLBI_1_TTL, ttl) |
+		FIELD_PREP(CMDQ_TLBI_1_TG, tg_enc) |
+		(iova & ~GENMASK_U64(11, 0));
+}
+
+/*
+ * @num: Number of 2^scale granules, must be >= 1.
+ */
+static inline u64 arm_smmu_tlb_inv_range_enc(u8 num, u8 scale)
+{
+	/* Keep the pre-DS 5-bit truncation when scale > 31 */
+	return FIELD_PREP(CMDQ_TLBI_0_NUM, num - 1) |
+		FIELD_PREP(CMDQ_TLBI_0_SCALE, scale & 0x1f);
+}
+
 #ifdef CONFIG_ARM_SMMU_V3_SVA
 bool arm_smmu_sva_supported(struct arm_smmu_device *smmu);
 void arm_smmu_sva_notifier_synchronize(void);
-- 
2.55.0.1082.g2b9226bbc0-goog