[PATCH v2 1/2] x86/IOMMU: address violations of MISRA C:2012 Rule 14.4

[Simone Ballarin <simone.ballarin@xxxxxxxxxxx>]

From: Maria Celeste Cesario <maria.celeste.cesario@xxxxxxxxxxx>

The xen sources contain violations of MISRA C:2012 Rule 14.4 whose
headline states:
"The controlling expression of an if statement and the controlling
expression of an iteration-statement shall have essentially Boolean type".

Add comparisons to avoid using enum constants as controlling expressions
to comply with Rule 14.4.
No functional change.

Signed-off-by: Maria Celeste Cesario  <maria.celeste.cesario@xxxxxxxxxxx>
Signed-off-by: Simone Ballarin  <simone.ballarin@xxxxxxxxxxx>
---
Changes in v2
- rename prefix from AMD/IOMMU to x86/IOMMU
- move changes on msi.c and hpet.c in this patch.
---
 xen/arch/x86/hpet.c                      | 6 +++---
 xen/arch/x86/msi.c                       | 4 ++--
 xen/drivers/passthrough/amd/iommu_init.c | 4 ++--
 xen/drivers/passthrough/vtd/iommu.c      | 4 ++--
 xen/drivers/passthrough/vtd/quirks.c     | 2 +-
 5 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/xen/arch/x86/hpet.c b/xen/arch/x86/hpet.c
index 7be26c6a9b..d1ddc8ddf6 100644
--- a/xen/arch/x86/hpet.c
+++ b/xen/arch/x86/hpet.c
@@ -279,7 +279,7 @@ static int hpet_msi_write(struct hpet_event_channel *ch, 
struct msi_msg *msg)
 {
     ch->msi.msg = *msg;
 
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         int rc = iommu_update_ire_from_msi(&ch->msi, msg);
 
@@ -353,7 +353,7 @@ static int __init hpet_setup_msi_irq(struct 
hpet_event_channel *ch)
     u32 cfg = hpet_read32(HPET_Tn_CFG(ch->idx));
     irq_desc_t *desc = irq_to_desc(ch->msi.irq);
 
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         ch->msi.hpet_id = hpet_blockid;
         ret = iommu_setup_hpet_msi(&ch->msi);
@@ -372,7 +372,7 @@ static int __init hpet_setup_msi_irq(struct 
hpet_event_channel *ch)
         ret = __hpet_setup_msi_irq(desc);
     if ( ret < 0 )
     {
-        if ( iommu_intremap )
+        if ( iommu_intremap != iommu_intremap_off )
             iommu_update_ire_from_msi(&ch->msi, NULL);
         return ret;
     }
diff --git a/xen/arch/x86/msi.c b/xen/arch/x86/msi.c
index 7f8e794254..72dce2e4ab 100644
--- a/xen/arch/x86/msi.c
+++ b/xen/arch/x86/msi.c
@@ -189,7 +189,7 @@ static int write_msi_msg(struct msi_desc *entry, struct 
msi_msg *msg)
 {
     entry->msg = *msg;
 
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         int rc;
 
@@ -555,7 +555,7 @@ int msi_free_irq(struct msi_desc *entry)
             destroy_irq(entry[nr].irq);
 
         /* Free the unused IRTE if intr remap enabled */
-        if ( iommu_intremap )
+        if ( iommu_intremap != iommu_intremap_off )
             iommu_update_ire_from_msi(entry + nr, NULL);
     }
 
diff --git a/xen/drivers/passthrough/amd/iommu_init.c 
b/xen/drivers/passthrough/amd/iommu_init.c
index 5515cb70fd..e02a09a9a7 100644
--- a/xen/drivers/passthrough/amd/iommu_init.c
+++ b/xen/drivers/passthrough/amd/iommu_init.c
@@ -1480,7 +1480,7 @@ int __init amd_iommu_init(bool xt)
             goto error_out;
     }
 
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
         register_keyhandler('V', &amd_iommu_dump_intremap_tables,
                             "dump IOMMU intremap tables", 0);
 
@@ -1498,7 +1498,7 @@ int __init amd_iommu_init_late(void)
 
     /* Further initialize the device table(s). */
     pci_init = true;
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
         rc = iterate_ivrs_mappings(amd_iommu_setup_device_table);
 
     for_each_amd_iommu ( iommu )
diff --git a/xen/drivers/passthrough/vtd/iommu.c 
b/xen/drivers/passthrough/vtd/iommu.c
index e13b7d99db..bd6d69a6f5 100644
--- a/xen/drivers/passthrough/vtd/iommu.c
+++ b/xen/drivers/passthrough/vtd/iommu.c
@@ -2543,7 +2543,7 @@ static int __must_check init_vtd_hw(bool resume)
     /*
      * Enable interrupt remapping
      */  
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         int apic;
         for ( apic = 0; apic < nr_ioapics; apic++ )
@@ -2559,7 +2559,7 @@ static int __must_check init_vtd_hw(bool resume)
             }
         }
     }
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
     {
         for_each_drhd_unit ( drhd )
         {
diff --git a/xen/drivers/passthrough/vtd/quirks.c 
b/xen/drivers/passthrough/vtd/quirks.c
index 5a56565ea8..950dcd56ef 100644
--- a/xen/drivers/passthrough/vtd/quirks.c
+++ b/xen/drivers/passthrough/vtd/quirks.c
@@ -392,7 +392,7 @@ void __init platform_quirks_init(void)
     map_igd_reg();
 
     /* Tylersburg interrupt remap quirk */
-    if ( iommu_intremap )
+    if ( iommu_intremap != iommu_intremap_off )
         tylersburg_intremap_quirk();
 }
 
-- 
2.40.0