Re: [PATCH v4 31/33] hw/nios2: Introduce Nios2MachineState

[Mark Cave-Ayland]

On 08/03/2022 07:20, Richard Henderson wrote:

> We want to move data from the heap into Nios2MachineState,
> which is not possible with DEFINE_MACHINE.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>   hw/nios2/10m50_devboard.c | 28 +++++++++++++++++++++++++---
>   1 file changed, 25 insertions(+), 3 deletions(-)
>
> diff --git a/hw/nios2/10m50_devboard.c b/hw/nios2/10m50_devboard.c
> index 3d1205b8bd..f245e0baa8 100644
> --- a/hw/nios2/10m50_devboard.c
> +++ b/hw/nios2/10m50_devboard.c
> @@ -36,10 +36,18 @@
>   
>   #include "boot.h"
>   
> +struct Nios2MachineState {
> +    MachineState parent_obj;
> +};
> +
> +#define TYPE_NIOS2_MACHINE  MACHINE_TYPE_NAME("10m50-ghrd")
> +OBJECT_DECLARE_TYPE(Nios2MachineState, MachineClass, NIOS2_MACHINE)
> +
>   #define BINARY_DEVICE_TREE_FILE    "10m50-devboard.dtb"
>   
>   static void nios2_10m50_ghrd_init(MachineState *machine)
>   {
> +    Nios2MachineState *nms = NIOS2_MACHINE(machine);
>       Nios2CPU *cpu;
>       DeviceState *dev;
>       MemoryRegion *address_space_mem = get_system_memory();
> @@ -101,15 +109,29 @@ static void nios2_10m50_ghrd_init(MachineState *machine)
>       cpu->exception_addr = 0xc8000120;
>       cpu->fast_tlb_miss_addr = 0xc0000100;
>   
> -    nios2_load_kernel(cpu, ram_base, ram_size, machine->initrd_filename,
> +    nios2_load_kernel(cpu, ram_base, ram_size, nms->parent_obj.initrd_filename,
>                         BINARY_DEVICE_TREE_FILE, NULL);

I think you should be able to keep this as machine->initrd_filename? Certainly there 
should be no direct access to parent_obj here, and if you did need it a QOM cast 
macro would be the way to do this.

>   }
>   
> -static void nios2_10m50_ghrd_machine_init(struct MachineClass *mc)
> +static void nios2_10m50_ghrd_class_init(ObjectClass *oc, void *data)
>   {
> +    MachineClass *mc = MACHINE_CLASS(oc);
> +
>       mc->desc = "Altera 10M50 GHRD Nios II design";
>       mc->init = nios2_10m50_ghrd_init;
>       mc->is_default = true;
>   }
>   
> -DEFINE_MACHINE("10m50-ghrd", nios2_10m50_ghrd_machine_init);
> +static const TypeInfo nios2_10m50_ghrd_type_info = {
> +    .name          = TYPE_NIOS2_MACHINE,
> +    .parent        = TYPE_MACHINE,
> +    .instance_size = sizeof(Nios2MachineState),
> +    .class_size    = sizeof(MachineClass),

Technically you can drop .class_size here since this should be inherited 
automatically from MachineClass.

> +    .class_init    = nios2_10m50_ghrd_class_init,
> +};
> +
> +static void nios2_10m50_ghrd_type_init(void)
> +{
> +    type_register_static(&nios2_10m50_ghrd_type_info);
> +}
> +type_init(nios2_10m50_ghrd_type_init);


ATB,

Mark.