Le 09/09/2023 à 11:48, Mark Cave-Ayland a écrit :
> Tests on real Q800 hardware show that the ESCC is addressable at multiple locations
> within the ESCC memory region - at least 0xc000, 0xc020 (as expected by the MacOS
> toolbox ROM) and 0xc040.
>
> All released NetBSD kernels before 10 use the 0xc000 address which causes a fatal
> error when running the MacOS booter. Add a single memory region alias at 0xc000
> to enable NetBSD kernels to start booting under QEMU.
>
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
> ---
> hw/m68k/q800.c | 6 ++++++
> include/hw/m68k/q800.h | 1 +
> 2 files changed, 7 insertions(+)
>
> diff --git a/hw/m68k/q800.c b/hw/m68k/q800.c
> index 5ae7c37760..b5b2cabc33 100644
> --- a/hw/m68k/q800.c
> +++ b/hw/m68k/q800.c
> @@ -451,6 +451,12 @@ static void q800_machine_init(MachineState *machine)
> memory_region_add_subregion(&m->macio, SCC_BASE - IO_BASE,
> sysbus_mmio_get_region(sysbus, 0));
>
> + /* Create alias for NetBSD */
> + memory_region_init_alias(&m->escc_alias, OBJECT(machine), "escc-alias",
> + sysbus_mmio_get_region(sysbus, 0), 0, 0x8);
> + memory_region_add_subregion(&m->macio, SCC_BASE - IO_BASE - 0x20,
> + &m->escc_alias);
> +
> /* SCSI */
>
> object_initialize_child(OBJECT(machine), "esp", &m->esp,
> diff --git a/include/hw/m68k/q800.h b/include/hw/m68k/q800.h
> index fbaacd88bd..348eaf4703 100644
> --- a/include/hw/m68k/q800.h
> +++ b/include/hw/m68k/q800.h
> @@ -67,6 +67,7 @@ struct Q800MachineState {
> MemoryRegion macio;
> MemoryRegion macio_alias;
> MemoryRegion machine_id;
> + MemoryRegion escc_alias;
> };
>
> #define TYPE_Q800_MACHINE MACHINE_TYPE_NAME("q800")
Reviewed-by: Laurent Vivier <laurent@vivier.eu>