Re: [PATCH v2] riscv: Generate devicetree only after machine initialization is complete

From: Alistair Francis <alistair23@gmail.com>
To: Guenter Roeck <linux@roeck-us.net>
Cc: Palmer Dabbelt <palmer@dabbelt.com>,
	Alistair Francis <alistair.francis@wdc.com>,
	 Weiwei Li <liweiwei@iscas.ac.cn>,
	Liu Zhiwei <zhiwei_liu@linux.alibaba.com>,
	 qemu-riscv@nongnu.org, qemu-devel@nongnu.org,
	 Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Subject: Re: [PATCH v2] riscv: Generate devicetree only after machine initialization is complete
Date: Mon, 10 Jul 2023 11:02:44 +1000	[thread overview]
Message-ID: <CAKmqyKNTywcdGAxfbh4UvPL_ZHYkw77ns-yGS-fBMWVWAavwBw@mail.gmail.com> (raw)
In-Reply-To: <20230706035937.1870483-1-linux@roeck-us.net>

On Thu, Jul 6, 2023 at 1:59 PM Guenter Roeck <linux@roeck-us.net> wrote:
>
> If the devicetree is created before machine initialization is complete,
> it misses dynamic devices. Specifically, the tpm device is not added
> to the devicetree file and is therefore not instantiated in Linux.
> Load/create devicetree in virt_machine_done() to solve the problem.
>
> Cc: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> Cc: Alistair Francis <alistair23@gmail.com>
> Cc: Daniel Henrique Barboza <dbarboza@ventanamicro.c>
> Fixes: 325b7c4e75 hw/riscv: Enable TPM backends
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Thanks!

Applied to riscv-to-apply.next

Alistair

> ---
> v2: Handle devicetree (load & create) entirely in machine_done function.
>
>  hw/riscv/virt.c | 22 +++++++++++-----------
>  1 file changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> index ed4c27487e..1c4bd823df 100644
> --- a/hw/riscv/virt.c
> +++ b/hw/riscv/virt.c
> @@ -1248,6 +1248,17 @@ static void virt_machine_done(Notifier *notifier, void *data)
>      uint64_t kernel_entry = 0;
>      BlockBackend *pflash_blk0;
>
> +    /* load/create device tree */
> +    if (machine->dtb) {
> +        machine->fdt = load_device_tree(machine->dtb, &s->fdt_size);
> +        if (!machine->fdt) {
> +            error_report("load_device_tree() failed");
> +            exit(1);
> +        }
> +    } else {
> +        create_fdt(s, memmap);
> +    }
> +
>      /*
>       * Only direct boot kernel is currently supported for KVM VM,
>       * so the "-bios" parameter is not supported when KVM is enabled.
> @@ -1508,17 +1519,6 @@ static void virt_machine_init(MachineState *machine)
>      }
>      virt_flash_map(s, system_memory);
>
> -    /* load/create device tree */
> -    if (machine->dtb) {
> -        machine->fdt = load_device_tree(machine->dtb, &s->fdt_size);
> -        if (!machine->fdt) {
> -            error_report("load_device_tree() failed");
> -            exit(1);
> -        }
> -    } else {
> -        create_fdt(s, memmap);
> -    }
> -
>      s->machine_done.notify = virt_machine_done;
>      qemu_add_machine_init_done_notifier(&s->machine_done);
>  }
> --
> 2.39.2
>