[RFC v1 6/7] iommu/arm-smmu-v3: Rearrange msi resv alloc functions

[shameer]

This moves the SW MSI reserve region allocation to probe fn.

Signed-off-by: shameer <shameerali.kolothum.thodi at huawei.com>
---
 drivers/iommu/arm-smmu-v3.c | 36 +++++++++++++++++++++++++++---------
 1 file changed, 27 insertions(+), 9 deletions(-)

diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c
index 770cc9e..e7a8a50 100644
--- a/drivers/iommu/arm-smmu-v3.c
+++ b/drivers/iommu/arm-smmu-v3.c
@@ -619,6 +619,9 @@ struct arm_smmu_device {
 
 	/* IOMMU core code handle */
 	struct iommu_device		iommu;
+
+	/* MSI Reserve region */
+	struct iommu_resv_region        *msi_region;
 };
 
 /* SMMU private data for each master */
@@ -1960,15 +1963,12 @@ static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
 static void arm_smmu_get_resv_regions(struct device *dev,
 				      struct list_head *head)
 {
-	struct iommu_resv_region *region;
-	int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO;
-
-	region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH,
-					 prot, IOMMU_RESV_SW_MSI);
-	if (!region)
-		return;
+	struct iommu_domain *domain = iommu_get_domain_for_dev(dev);
+	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+	struct arm_smmu_device *smmu = smmu_domain->smmu;
 
-	list_add_tail(&region->list, head);
+	if (smmu && smmu->msi_region)
+		list_add_tail(&smmu->msi_region->list, head);
 
 	iommu_dma_get_resv_regions(dev, head);
 }
@@ -1978,8 +1978,13 @@ static void arm_smmu_put_resv_regions(struct device *dev,
 {
 	struct iommu_resv_region *entry, *next;
 
-	list_for_each_entry_safe(entry, next, head, list)
+	list_for_each_entry_safe(entry, next, head, list) {
+		if (entry->type == IOMMU_RESV_SW_MSI ||
+				entry->type == IOMMU_RESV_MSI)
+			continue;
+
 		kfree(entry);
+	}
 }
 
 static struct iommu_ops arm_smmu_ops = {
@@ -2711,6 +2716,17 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev,
 	return ret;
 }
 
+static struct iommu_resv_region *arm_smmu_alloc_msi_region(
+				struct arm_smmu_device *smmu)
+{
+	struct iommu_resv_region *region;
+	int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO;
+
+	region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH,
+					prot, IOMMU_RESV_SW_MSI);
+	return region;
+}
+
 static int arm_smmu_device_probe(struct platform_device *pdev)
 {
 	int irq, ret;
@@ -2756,6 +2772,8 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
 	if (irq > 0)
 		smmu->gerr_irq = irq;
 
+	smmu->msi_region = arm_smmu_alloc_msi_region(smmu);
+
 	if (dev->of_node) {
 		ret = arm_smmu_device_dt_probe(pdev, smmu);
 	} else {
-- 
2.5.0