[Qemu-devel] [PATCH 18/34] pseries: Remove C bitfields from xics code

[Alexander Graf]

From: David Gibson <address@hidden>

The XICS interrupt controller emulation uses some C bitfield variables in
its internal state structure.  This makes like awkward for saving the state
because we don't have easy VMSTATE helpers for bitfields.

This patch removes the bitfields, instead using explicit bit masking in a
single status variable.

Signed-off-by: David Gibson <address@hidden>
Signed-off-by: Alexander Graf <address@hidden>
---
 hw/xics.c |   43 ++++++++++++++++++++++++-------------------
 1 files changed, 24 insertions(+), 19 deletions(-)

diff --git a/hw/xics.c b/hw/xics.c
index a8a08ce..648af25 100644
--- a/hw/xics.c
+++ b/hw/xics.c
@@ -165,11 +165,12 @@ struct ics_irq_state {
     int server;
     uint8_t priority;
     uint8_t saved_priority;
+#define XICS_STATUS_ASSERTED           0x1
+#define XICS_STATUS_SENT               0x2
+#define XICS_STATUS_REJECTED           0x4
+#define XICS_STATUS_MASKED_PENDING     0x8
+    uint8_t status;
     enum xics_irq_type type;
-    int asserted:1;
-    int sent:1;
-    int rejected:1;
-    int masked_pending:1;
 };
 
 struct ics_state {
@@ -191,8 +192,8 @@ static void resend_msi(struct ics_state *ics, int srcno)
     struct ics_irq_state *irq = ics->irqs + srcno;
 
     /* FIXME: filter by server#? */
-    if (irq->rejected) {
-        irq->rejected = 0;
+    if (irq->status & XICS_STATUS_REJECTED) {
+        irq->status &= ~XICS_STATUS_REJECTED;
         if (irq->priority != 0xff) {
             icp_irq(ics->icp, irq->server, srcno + ics->offset,
                     irq->priority);
@@ -204,8 +205,10 @@ static void resend_lsi(struct ics_state *ics, int srcno)
 {
     struct ics_irq_state *irq = ics->irqs + srcno;
 
-    if ((irq->priority != 0xff) && irq->asserted && !irq->sent) {
-        irq->sent = 1;
+    if ((irq->priority != 0xff)
+        && (irq->status & XICS_STATUS_ASSERTED)
+        && !(irq->status & XICS_STATUS_SENT)) {
+        irq->status |= XICS_STATUS_SENT;
         icp_irq(ics->icp, irq->server, srcno + ics->offset, irq->priority);
     }
 }
@@ -216,7 +219,7 @@ static void set_irq_msi(struct ics_state *ics, int srcno, 
int val)
 
     if (val) {
         if (irq->priority == 0xff) {
-            irq->masked_pending = 1;
+            irq->status |= XICS_STATUS_MASKED_PENDING;
             /* masked pending */ ;
         } else  {
             icp_irq(ics->icp, irq->server, srcno + ics->offset, irq->priority);
@@ -228,7 +231,11 @@ static void set_irq_lsi(struct ics_state *ics, int srcno, 
int val)
 {
     struct ics_irq_state *irq = ics->irqs + srcno;
 
-    irq->asserted = val;
+    if (val) {
+        irq->status |= XICS_STATUS_ASSERTED;
+    } else {
+        irq->status &= ~XICS_STATUS_ASSERTED;
+    }
     resend_lsi(ics, srcno);
 }
 
@@ -248,11 +255,12 @@ static void write_xive_msi(struct ics_state *ics, int 
srcno)
 {
     struct ics_irq_state *irq = ics->irqs + srcno;
 
-    if (!irq->masked_pending || (irq->priority == 0xff)) {
+    if (!(irq->status & XICS_STATUS_MASKED_PENDING)
+        || (irq->priority == 0xff)) {
         return;
     }
 
-    irq->masked_pending = 0;
+    irq->status &= ~XICS_STATUS_MASKED_PENDING;
     icp_irq(ics->icp, irq->server, srcno + ics->offset, irq->priority);
 }
 
@@ -281,8 +289,8 @@ static void ics_reject(struct ics_state *ics, int nr)
 {
     struct ics_irq_state *irq = ics->irqs + nr - ics->offset;
 
-    irq->rejected = 1; /* Irrelevant but harmless for LSI */
-    irq->sent = 0; /* Irrelevant but harmless for MSI */
+    irq->status |= XICS_STATUS_REJECTED; /* Irrelevant but harmless for LSI */
+    irq->status &= ~XICS_STATUS_SENT; /* Irrelevant but harmless for MSI */
 }
 
 static void ics_resend(struct ics_state *ics)
@@ -307,7 +315,7 @@ static void ics_eoi(struct ics_state *ics, int nr)
     struct ics_irq_state *irq = ics->irqs + srcno;
 
     if (irq->type == XICS_LSI) {
-        irq->sent = 0;
+        irq->status &= ~XICS_STATUS_SENT;
     }
 }
 
@@ -506,10 +514,7 @@ static void xics_reset(void *opaque)
     for (i = 0; i < ics->nr_irqs; i++) {
         /* Reset everything *except* the type */
         ics->irqs[i].server = 0;
-        ics->irqs[i].asserted = 0;
-        ics->irqs[i].sent = 0;
-        ics->irqs[i].rejected = 0;
-        ics->irqs[i].masked_pending = 0;
+        ics->irqs[i].status = 0;
         ics->irqs[i].priority = 0xff;
         ics->irqs[i].saved_priority = 0xff;
     }
-- 
1.6.0.2