hw/m68k: add Nubus macfb video card

This patch adds support for a graphic framebuffer device.
This device can be added as a sysbus device or as a NuBus device.

It is accessed as a framebuffer but the color palette can be set.

Co-developed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Hervé Poussineau <hpoussin@reactos.org>
Reviewed-by: Thomas Huth <huth@tuxfamily.org>
Message-Id: <20191026164546.30020-9-laurent@vivier.eu>

MAINTAINERS

@@ -922,8 +922,10 @@ M: Laurent Vivier <laurent@vivier.eu>
 S: Maintained
 F: hw/misc/mac_via.c
 F: hw/nubus/*
+F: hw/display/macfb.c
 F: include/hw/misc/mac_via.h
 F: include/hw/nubus/*
+F: include/hw/display/macfb.h
 
 MicroBlaze Machines
 -------------------

arch_init.c

@@ -38,6 +38,10 @@
 int graphic_width = 1024;
 int graphic_height = 768;
 int graphic_depth = 8;
+#elif defined(TARGET_M68K)
+int graphic_width = 800;
+int graphic_height = 600;
+int graphic_depth = 8;
 #else
 int graphic_width = 800;
 int graphic_height = 600;

hw/display/Kconfig

@@ -132,3 +132,8 @@ config ATI_VGA
     select VGA
     select BITBANG_I2C
     select DDC
+
+config MACFB
+    bool
+    select FRAMEBUFFER
+    depends on NUBUS

hw/display/Makefile.objs

@@ -26,6 +26,7 @@ common-obj-$(CONFIG_EXYNOS4) += exynos4210_fimd.o
 common-obj-$(CONFIG_FRAMEBUFFER) += framebuffer.o
 obj-$(CONFIG_MILKYMIST) += milkymist-vgafb.o
 common-obj-$(CONFIG_ZAURUS) += tc6393xb.o
+common-obj-$(CONFIG_MACFB) += macfb.o
 
 obj-$(CONFIG_MILKYMIST_TMU2) += milkymist-tmu2.o
 milkymist-tmu2.o-cflags := $(X11_CFLAGS) $(OPENGL_CFLAGS)