[Qemu-devel] [PATCH 2/4] pci: track IRQ status

["Michael S. Tsirkin" <mst@redhat.com>]

track IRQ status in preparation for PCI_STATUS_INTERRUPT support

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
 hw/pci.c |   10 +++++++++-
 hw/pci.h |    3 +++
 2 files changed, 12 insertions(+), 1 deletions(-)

diff --git a/hw/pci.c b/hw/pci.c
index 5ff0d46..7717461 100644
--- a/hw/pci.c
+++ b/hw/pci.c
@@ -108,6 +108,7 @@ static void pci_device_reset(PCIDevice *dev)
     int r;
 
     memset(dev->irq_state, 0, sizeof dev->irq_state);
+    dev->irq_status = 0;
     dev->config[PCI_COMMAND] &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY |
                                   PCI_COMMAND_MASTER);
     dev->config[PCI_CACHE_LINE_SIZE] = 0x0;
@@ -318,7 +319,12 @@ void pci_device_save(PCIDevice *s, QEMUFile *f)
 
 int pci_device_load(PCIDevice *s, QEMUFile *f)
 {
-    return vmstate_load_state(f, pci_get_vmstate(s), s, s->version_id);
+    int ret, i;
+    ret = vmstate_load_state(f, pci_get_vmstate(s), s, s->version_id);
+    for (i = 0; i < ARRAY_SIZE(s->irq_state); ++i) {
+        s->irq_status += s->irq_state[i];
+    }
+    return ret;
 }
 
 static int pci_set_default_subsystem_id(PCIDevice *pci_dev)
@@ -502,6 +508,7 @@ static PCIDevice *do_pci_register_device(PCIDevice *pci_dev, PCIBus *bus,
     pci_dev->devfn = devfn;
     pstrcpy(pci_dev->name, sizeof(pci_dev->name), name);
     memset(pci_dev->irq_state, 0, sizeof(pci_dev->irq_state));
+    pci_dev->irq_status = 0;
     pci_config_alloc(pci_dev);
 
     header_type &= ~PCI_HEADER_TYPE_MULTI_FUNCTION;
@@ -906,6 +913,7 @@ static void pci_set_irq(void *opaque, int irq_num, int level)
         return;
 
     pci_dev->irq_state[irq_num] = level;
+    pci_dev->irq_status += change;
     pci_change_irq_level(pci_dev, irq_num, change);
 }
 
diff --git a/hw/pci.h b/hw/pci.h
index 3e8abad..2e172f6 100644
--- a/hw/pci.h
+++ b/hw/pci.h
@@ -222,6 +222,9 @@ struct PCIDevice {
     /* Current IRQ levels.  Used internally by the generic PCI code.  */
     int irq_state[PCI_NUM_PINS];
 
+    /* Sum of all irq levels. Used to implement irq status register. */
+    int irq_status;
+
     /* Capability bits */
     uint32_t cap_present;
 
-- 
1.6.5.2.143.g8cc62