[PATCH v4 4/8] iommu/arm-smmu-v3: Remove strtab_base/cfg

[Jason Gunthorpe]

These values can be computed from the other values already stored in the
config. Move the calculation to arm_smmu_write_strtab() and do it directly
before writing the registers.

This moves all the logic to calculate the two registers into one function
from three and saves an unimportant 16 bytes from the arm_smmu_device.

Suggested-by: Nicolin Chen <nicolinc at nvidia.com>
Reviewed-by: Nicolin Chen <nicolinc at nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 55 ++++++++++-----------
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h |  2 -
 2 files changed, 27 insertions(+), 30 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 336803fb1f895e..bb6c556995a7a7 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -3627,7 +3627,6 @@ static int arm_smmu_init_queues(struct arm_smmu_device *smmu)
 
 static int arm_smmu_init_strtab_2lvl(struct arm_smmu_device *smmu)
 {
-	u64 reg;
 	u32 l1size;
 	struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg;
 	unsigned int last_sid_idx =
@@ -3651,13 +3650,6 @@ static int arm_smmu_init_strtab_2lvl(struct arm_smmu_device *smmu)
 		return -ENOMEM;
 	}
 
-	/* Configure strtab_base_cfg for 2 levels */
-	reg  = FIELD_PREP(STRTAB_BASE_CFG_FMT, STRTAB_BASE_CFG_FMT_2LVL);
-	reg |= FIELD_PREP(STRTAB_BASE_CFG_LOG2SIZE,
-			  ilog2(cfg->l2.num_l1_ents) + STRTAB_SPLIT);
-	reg |= FIELD_PREP(STRTAB_BASE_CFG_SPLIT, STRTAB_SPLIT);
-	cfg->strtab_base_cfg = reg;
-
 	cfg->l2.l2ptrs = devm_kcalloc(smmu->dev, cfg->l2.num_l1_ents,
 				      sizeof(*cfg->l2.l2ptrs), GFP_KERNEL);
 	if (!cfg->l2.l2ptrs)
@@ -3668,7 +3660,6 @@ static int arm_smmu_init_strtab_2lvl(struct arm_smmu_device *smmu)
 
 static int arm_smmu_init_strtab_linear(struct arm_smmu_device *smmu)
 {
-	u64 reg;
 	u32 size;
 	struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg;
 
@@ -3684,34 +3675,21 @@ static int arm_smmu_init_strtab_linear(struct arm_smmu_device *smmu)
 	}
 	cfg->linear.num_ents = 1 << smmu->sid_bits;
 
-	/* Configure strtab_base_cfg for a linear table covering all SIDs */
-	reg  = FIELD_PREP(STRTAB_BASE_CFG_FMT, STRTAB_BASE_CFG_FMT_LINEAR);
-	reg |= FIELD_PREP(STRTAB_BASE_CFG_LOG2SIZE, smmu->sid_bits);
-	cfg->strtab_base_cfg = reg;
-
 	arm_smmu_init_initial_stes(cfg->linear.table, cfg->linear.num_ents);
 	return 0;
 }
 
 static int arm_smmu_init_strtab(struct arm_smmu_device *smmu)
 {
-	u64 reg;
 	int ret;
 
-	if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
+	if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB)
 		ret = arm_smmu_init_strtab_2lvl(smmu);
-		reg = smmu->strtab_cfg.l2.l1_dma & STRTAB_BASE_ADDR_MASK;
-	} else {
+	else
 		ret = arm_smmu_init_strtab_linear(smmu);
-		reg = smmu->strtab_cfg.linear.ste_dma & STRTAB_BASE_ADDR_MASK;
-	}
 	if (ret)
 		return ret;
 
-	/* Set the strtab base address */
-	reg |= STRTAB_BASE_RA;
-	smmu->strtab_cfg.strtab_base = reg;
-
 	ida_init(&smmu->vmid_map);
 
 	return 0;
@@ -3927,6 +3905,30 @@ static int arm_smmu_device_disable(struct arm_smmu_device *smmu)
 	return ret;
 }
 
+static void arm_smmu_write_strtab(struct arm_smmu_device *smmu)
+{
+	struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg;
+	dma_addr_t dma;
+	u32 reg;
+
+	if (smmu->features & ARM_SMMU_FEAT_2_LVL_STRTAB) {
+		reg = FIELD_PREP(STRTAB_BASE_CFG_FMT,
+				 STRTAB_BASE_CFG_FMT_2LVL) |
+		      FIELD_PREP(STRTAB_BASE_CFG_LOG2SIZE,
+				 ilog2(cfg->l2.num_l1_ents) + STRTAB_SPLIT) |
+		      FIELD_PREP(STRTAB_BASE_CFG_SPLIT, STRTAB_SPLIT);
+		dma = cfg->l2.l1_dma;
+	} else {
+		reg = FIELD_PREP(STRTAB_BASE_CFG_FMT,
+				 STRTAB_BASE_CFG_FMT_LINEAR) |
+		      FIELD_PREP(STRTAB_BASE_CFG_LOG2SIZE, smmu->sid_bits);
+		dma = cfg->linear.ste_dma;
+	}
+	writeq_relaxed((dma & STRTAB_BASE_ADDR_MASK) | STRTAB_BASE_RA,
+		       smmu->base + ARM_SMMU_STRTAB_BASE);
+	writel_relaxed(reg, smmu->base + ARM_SMMU_STRTAB_BASE_CFG);
+}
+
 static int arm_smmu_device_reset(struct arm_smmu_device *smmu)
 {
 	int ret;
@@ -3962,10 +3964,7 @@ static int arm_smmu_device_reset(struct arm_smmu_device *smmu)
 	writel_relaxed(reg, smmu->base + ARM_SMMU_CR2);
 
 	/* Stream table */
-	writeq_relaxed(smmu->strtab_cfg.strtab_base,
-		       smmu->base + ARM_SMMU_STRTAB_BASE);
-	writel_relaxed(smmu->strtab_cfg.strtab_base_cfg,
-		       smmu->base + ARM_SMMU_STRTAB_BASE_CFG);
+	arm_smmu_write_strtab(smmu);
 
 	/* Command queue */
 	writeq_relaxed(smmu->cmdq.q.q_base, smmu->base + ARM_SMMU_CMDQ_BASE);
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 23918a547cbbce..33a8bee1b82e3b 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -658,8 +658,6 @@ struct arm_smmu_strtab_cfg {
 			unsigned int num_l1_ents;
 		} l2;
 	};
-	u64				strtab_base;
-	u32				strtab_base_cfg;
 };
 
 struct arm_smmu_impl_ops {
-- 
2.46.0