[Qemu-devel] [PATCH] Add an isa device for SGA

[Glauber Costa <glommer@redhat.com>]

This patch adds a dummy legacy ISA device whose responsibility is to
deploy sgabios, an option rom for a serial graphics adapter.
The proposal is that this device is always-on when -nographics,
but can otherwise be enable in any setup when -device sga is used.

Signed-off-by: Glauber Costa <glommer@redhat.com>
---
 Makefile.target |    2 +-
 hw/pc.c         |    2 ++
 hw/pc.h         |    3 +++
 hw/sga.c        |   49 +++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 55 insertions(+), 1 deletions(-)
 create mode 100644 hw/sga.c

diff --git a/Makefile.target b/Makefile.target
index fdbdc6c..004ea7e 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -224,7 +224,7 @@ obj-$(CONFIG_KVM) += ivshmem.o
 # Hardware support
 obj-i386-y += vga.o
 obj-i386-y += mc146818rtc.o i8259.o pc.o
-obj-i386-y += cirrus_vga.o apic.o ioapic.o piix_pci.o
+obj-i386-y += cirrus_vga.o sga.o apic.o ioapic.o piix_pci.o
 obj-i386-y += vmport.o
 obj-i386-y += device-hotplug.o pci-hotplug.o smbios.o wdt_ib700.o
 obj-i386-y += extboot.o
diff --git a/hw/pc.c b/hw/pc.c
index 8d351ba..56c3887 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -1096,6 +1096,8 @@ void pc_vga_init(PCIBus *pci_bus)
             isa_vga_init();
         }
     }
+
+    isa_sga_init();
 }
 
 static void cpu_request_exit(void *opaque, int irq, int level)
diff --git a/hw/pc.h b/hw/pc.h
index 1291e2d..a00e054 100644
--- a/hw/pc.h
+++ b/hw/pc.h
@@ -219,6 +219,9 @@ int isa_vga_mm_init(target_phys_addr_t vram_base,
 void pci_cirrus_vga_init(PCIBus *bus);
 void isa_cirrus_vga_init(void);
 
+/* serial graphics */
+void isa_sga_init(void);
+
 /* ne2000.c */
 static inline bool isa_ne2000_init(int base, int irq, NICInfo *nd)
 {
diff --git a/hw/sga.c b/hw/sga.c
new file mode 100644
index 0000000..411191b
--- /dev/null
+++ b/hw/sga.c
@@ -0,0 +1,49 @@
+#include "pci.h"
+#include "pc.h"
+#include "loader.h"
+#include "sysemu.h"
+
+#define SGABIOS_FILENAME "sgabios.bin"
+
+typedef struct ISAGAState {
+    ISADevice dev;
+} ISASGAState;
+
+/* We can have both -device, and the initfn called, so better
+ * avoid to have the rom loaded twice */
+static void deploy_rom(void)
+{
+    static int rom_deployed = 0;
+
+    if (!rom_deployed++) {
+        rom_add_vga(SGABIOS_FILENAME);
+    }
+}
+
+static int isa_cirrus_vga_initfn(ISADevice *dev)
+{
+    deploy_rom();
+
+    return 0;
+}
+
+void isa_sga_init(void)
+{
+    if (display_type == DT_NOGRAPHIC) {
+        deploy_rom();
+    }
+}
+
+static ISADeviceInfo sga_info = {
+    .qdev.name    = "sga",
+    .qdev.desc    = "Serial Graphics Adapter",
+    .qdev.size    = sizeof(ISASGAState),
+    .init         = isa_cirrus_vga_initfn,
+};
+
+static void sga_register(void)
+{
+      isa_qdev_register(&sga_info);
+}
+
+device_init(sga_register);
-- 
1.7.4.2