xen/pt: Use xen_host_pci_get_[byte|word] instead of dev.config

During init time we treat the dev.config area as a cache
of the host view. However during execution time we treat it
as guest view (by the generic PCI API). We need to sync Xen's
code to the generic PCI API view. This is the first step
by replacing all of the code that uses dev.config or
pci_get_[byte|word] to get host value to actually use the
xen_host_pci_get_[byte|word] functions.

Interestingly in 'xen_pt_ptr_reg_init' we also needed to swap
reg_field from uint32_t to uint8_t - since the access is only
for one byte not four bytes. We can split this as a seperate
patch however we would have to use a cast to thwart compiler
warnings in the meantime.

We also truncated 'flags' to 'flag' to make the code fit within
the 80 characters.

Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>

1 files changed, 20 insertions, 4 deletions

diff --git a/hw/xen/xen_pt.c b/hw/xen/xen_pt.c
index 3b1544c..1c84d3d 100644
--- a/hw/xen/xen_pt.c
+++ b/hw/xen/xen_pt.c
@@ -702,7 +702,7 @@ static int xen_pt_initfn(PCIDevice *d)
 {
     XenPCIPassthroughState *s = XEN_PT_DEVICE(d);
     int rc = 0;
-    uint8_t machine_irq = 0;
+    uint8_t machine_irq = 0, scratch;
     uint16_t cmd = 0;
     int pirq = XEN_PT_UNASSIGNED_PIRQ;
 
@@ -768,7 +768,12 @@ static int xen_pt_initfn(PCIDevice *d)
     }
 
     /* Bind interrupt */
-    if (!s->dev.config[PCI_INTERRUPT_PIN]) {
+    rc = xen_host_pci_get_byte(&s->real_device, PCI_INTERRUPT_PIN, &scratch);
+    if (rc) {
+        XEN_PT_ERR(d, "Failed to read PCI_INTERRUPT_PIN! (rc:%d)\n", rc);
+        scratch = 0;
+    }
+    if (!scratch) {
         XEN_PT_LOG(d, "no pin interrupt\n");
         goto out;
     }
@@ -818,8 +823,19 @@ static int xen_pt_initfn(PCIDevice *d)
 
 out:
     if (cmd) {
-        xen_host_pci_set_word(&s->real_device, PCI_COMMAND,
-                              pci_get_word(d->config + PCI_COMMAND) | cmd);
+        uint16_t val;
+
+        rc = xen_host_pci_get_word(&s->real_device, PCI_COMMAND, &val);
+        if (rc) {
+            XEN_PT_ERR(d, "Failed to read PCI_COMMAND! (rc: %d)\n", rc);
+        } else {
+            val |= cmd;
+            rc = xen_host_pci_set_word(&s->real_device, PCI_COMMAND, val);
+            if (rc) {
+                XEN_PT_ERR(d, "Failed to write PCI_COMMAND val=0x%x!(rc: %d)\n",
+                           val, rc);
+            }
+        }
     }
 
     memory_listener_register(&s->memory_listener, &s->dev.bus_master_as);