macfb: add common monitor modes supported by the MacOS toolbox ROM

The monitor modes table is found by experimenting with the Monitors Control
Panel in MacOS and analysing the reads/writes. From this it can be found that
the mode is controlled by writes to the DAFB_MODE_CTRL1 and DAFB_MODE_CTRL2
registers.

Implement the first block of DAFB registers as a register array including the
existing sense register, the newly discovered control registers above, and also
the DAFB_MODE_VADDR1 and DAFB_MODE_VADDR2 registers which are used by NetBSD to
determine the current video mode.

These experiments also show that the offset of the start of video RAM and the
stride can change depending upon the monitor mode, so update macfb_draw_graphic()
and both the BI_MAC_VADDR and BI_MAC_VROW bootinfo for the q800 machine
accordingly.

Finally update macfb_common_realize() so that only the resolution and depth
supported by the display type can be specified on the command line, and add an
error hint showing the list of supported resolutions and depths if the user tries
to specify an invalid display mode.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20211007221253.29024-10-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

1 files changed, 7 insertions, 4 deletions

diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c
index 5223b880bc..df3fd3711e 100644
--- a/hw/m68k/q800.c
+++ b/hw/m68k/q800.c
@@ -74,7 +74,7 @@
  * is needed by the kernel to have early display and
  * thus provided by the bootloader
  */
-#define VIDEO_BASE            0xf9001000
+#define VIDEO_BASE            0xf9000000
 
 #define MAC_CLOCK  3686418
 
@@ -221,6 +221,7 @@ static void q800_init(MachineState *machine)
     uint8_t *prom;
     const int io_slice_nb = (IO_SIZE / IO_SLICE) - 1;
     int i, checksum;
+    MacFbMode *macfb_mode;
     ram_addr_t ram_size = machine->ram_size;
     const char *kernel_filename = machine->kernel_filename;
     const char *initrd_filename = machine->initrd_filename;
@@ -428,6 +429,8 @@ static void q800_init(MachineState *machine)
     }
     qdev_realize_and_unref(dev, BUS(nubus), &error_fatal);
 
+    macfb_mode = (NUBUS_MACFB(dev)->macfb).mode;
+
     cs = CPU(cpu);
     if (linux_boot) {
         uint64_t high;
@@ -450,12 +453,12 @@ static void q800_init(MachineState *machine)
         BOOTINFO1(cs->as, parameters_base,
                   BI_MAC_MEMSIZE, ram_size >> 20); /* in MB */
         BOOTINFO2(cs->as, parameters_base, BI_MEMCHUNK, 0, ram_size);
-        BOOTINFO1(cs->as, parameters_base, BI_MAC_VADDR, VIDEO_BASE);
+        BOOTINFO1(cs->as, parameters_base, BI_MAC_VADDR,
+                  VIDEO_BASE + macfb_mode->offset);
         BOOTINFO1(cs->as, parameters_base, BI_MAC_VDEPTH, graphic_depth);
         BOOTINFO1(cs->as, parameters_base, BI_MAC_VDIM,
                   (graphic_height << 16) | graphic_width);
-        BOOTINFO1(cs->as, parameters_base, BI_MAC_VROW,
-                  (graphic_width * graphic_depth + 7) / 8);
+        BOOTINFO1(cs->as, parameters_base, BI_MAC_VROW, macfb_mode->stride);
         BOOTINFO1(cs->as, parameters_base, BI_MAC_SCCBASE, SCC_BASE);
 
         rom = g_malloc(sizeof(*rom));