iommu/amd: Move interrupt setup code into seperate function

For interrupt remapping the enablement of the IOMMU MSI
interrupt needs to be deferred because the IOMMU itself will
be initialized before the io-apics are up and running. So
the code to setup the MSI is moved seperated from the
hardware-setup routine now.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

drivers/iommu/amd_iommu_init.c

@@ -196,6 +196,8 @@ static u32 rlookup_table_size;	/* size if the rlookup table */
  */
 extern void iommu_flush_all_caches(struct amd_iommu *iommu);
 
+static int __init amd_iommu_enable_interrupts(void);
+
 static inline void update_last_devid(u16 devid)
 {
 	if (devid > amd_iommu_last_bdf)
@@ -1383,7 +1385,6 @@ static void enable_iommus(void)
 		iommu_enable_ppr_log(iommu);
 		iommu_enable_gt(iommu);
 		iommu_set_exclusion_range(iommu);
-		iommu_init_msi(iommu);
 		iommu_enable(iommu);
 		iommu_flush_all_caches(iommu);
 	}
@@ -1411,6 +1412,8 @@ static void amd_iommu_resume(void)
 
 	/* re-load the hardware */
 	enable_iommus();
+
+	amd_iommu_enable_interrupts();
 }
 
 static int amd_iommu_suspend(void)
@@ -1595,6 +1598,21 @@ int __init amd_iommu_init_hardware(void)
 	return ret;
 }
 
+static int __init amd_iommu_enable_interrupts(void)
+{
+	struct amd_iommu *iommu;
+	int ret = 0;
+
+	for_each_iommu(iommu) {
+		ret = iommu_init_msi(iommu);
+		if (ret)
+			goto out;
+	}
+
+out:
+	return ret;
+}
+
 /*
  * This is the core init function for AMD IOMMU hardware in the system.
  * This function is called from the generic x86 DMA layer initialization
@@ -1612,6 +1630,10 @@ static int __init amd_iommu_init(void)
 	if (ret)
 		goto out;
 
+	ret = amd_iommu_enable_interrupts();
+	if (ret)
+		goto free;
+
 	if (iommu_pass_through)
 		ret = amd_iommu_init_passthrough();
 	else