pciinit: Enable default VGA device

As QEMU gains PCI bridge and PCIe root port support, we won't always
find the VGA device on the root bus.  We therefore need to add support
to find and enable a VGA device and the path to it through the VGA
Enable support in the PCI bridge control register.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/src/optionroms.c b/src/optionroms.c
index caa215106bff27b2108d71ed8bfbbc276c877c03..ac92613b142777bc9568f2b4e5c6285c22bc501a 100644 (file)
--- a/src/optionroms.c
+++ b/src/optionroms.c
@@ -213,7 +213,7 @@ run_file_roms(const char *prefix, int isvga, u64 *sources)
  ****************************************************************/
 
 // Verify device is a vga device with legacy address decoding enabled.
-static int
+int
 is_pci_vga(struct pci_device *pci)
 {
     if (pci->class != PCI_CLASS_DISPLAY_VGA)

diff --git a/src/pciinit.c b/src/pciinit.c
index ce0a4ccbc6e41417b9b1f6603624daebd998efd5..bb9355fc3b24f16e18e1e01d1fe7402b7b132fec 100644 (file)
--- a/src/pciinit.c
+++ b/src/pciinit.c
@@ -316,6 +316,44 @@ static void pci_bios_init_devices(void)
     }
 }
 
+static void pci_enable_default_vga(void)
+{
+    struct pci_device *pci;
+
+    foreachpci(pci) {
+        if (is_pci_vga(pci)) {
+            dprintf(1, "PCI: Using %02x:%02x.%x for primary VGA\n",
+                    pci_bdf_to_bus(pci->bdf), pci_bdf_to_dev(pci->bdf),
+                    pci_bdf_to_fn(pci->bdf));
+            return;
+        }
+    }
+
+    pci = pci_find_class(PCI_CLASS_DISPLAY_VGA);
+    if (!pci) {
+        dprintf(1, "PCI: No VGA devices found\n");
+        return;
+    }
+
+    dprintf(1, "PCI: Enabling %02x:%02x.%x for primary VGA\n",
+            pci_bdf_to_bus(pci->bdf), pci_bdf_to_dev(pci->bdf),
+            pci_bdf_to_fn(pci->bdf));
+
+    pci_config_maskw(pci->bdf, PCI_COMMAND, 0,
+                     PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
+
+    while (pci->parent) {
+        pci = pci->parent;
+
+        dprintf(1, "PCI: Setting VGA enable on bridge %02x:%02x.%x\n",
+                pci_bdf_to_bus(pci->bdf), pci_bdf_to_dev(pci->bdf),
+                pci_bdf_to_fn(pci->bdf));
+
+        pci_config_maskw(pci->bdf, PCI_BRIDGE_CONTROL, 0, PCI_BRIDGE_CTL_VGA);
+        pci_config_maskw(pci->bdf, PCI_COMMAND, 0,
+                         PCI_COMMAND_IO | PCI_COMMAND_MEMORY);
+    }
+}
 
 /****************************************************************
  * Platform device initialization
@@ -804,4 +842,6 @@ pci_setup(void)
     pci_bios_init_devices();
 
     free(busses);
+
+    pci_enable_default_vga();
 }

diff --git a/src/util.h b/src/util.h
index af029fc03590fd7925be77daaab97a9047b50e93..99aff786053b9549f97344c40446a329db6607ef 100644 (file)
--- a/src/util.h
+++ b/src/util.h
@@ -344,6 +344,7 @@ void vgahook_setup(struct pci_device *pci);
 
 // optionroms.c
 void call_bcv(u16 seg, u16 ip);
+int is_pci_vga(struct pci_device *pci);
 void optionrom_setup(void);
 void vgarom_setup(void);
 void s3_resume_vga(void);