From mboxrd@z Thu Jan  1 00:00:00 1970
From: Will Deacon <will.deacon@arm.com>
Subject: Re: [PATCH kvmtool 2/6] arm: fdt: add stdout-path to /chosen node
Date: Wed, 30 Jan 2019 18:20:19 +0000
Message-ID: <20190130182019.GF18558@fuggles.cambridge.arm.com>
References: <20190125180801.209910-1-andre.przywara@arm.com>
 <20190125180801.209910-3-andre.przywara@arm.com>
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To: Andre Przywara <andre.przywara@arm.com>
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On Fri, Jan 25, 2019 at 06:07:57PM +0000, Andre Przywara wrote:
> The DT spec describes the stdout-path property in the /chosen node to
> contain the DT path for a default device usable for outputting characters.
> The Linux kernel uses this for earlycon (without further parameters),
> other DT users might rely on this as well.
> 
> Add a property containing the path to our emulated 8250 serial device.
> 
> Even when we use the virtio console, the serial console is still there
> and works, so we can expose this unconditionally. Putting the virtio
> console path in there will not work anyway.
> 
> Signed-off-by: Andre Przywara <andre.przywara@arm.com>
> ---
>  arm/fdt.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arm/fdt.c b/arm/fdt.c
> index 28ba1c2c..8cda3ded 100644
> --- a/arm/fdt.c
> +++ b/arm/fdt.c
> @@ -143,6 +143,7 @@ static int setup_fdt(struct kvm *kvm)
>  	_FDT(fdt_property_cell(fdt, "linux,pci-probe-only", 1));
>  	_FDT(fdt_property_string(fdt, "bootargs", kvm->cfg.real_cmdline));
>  	_FDT(fdt_property_u64(fdt, "kaslr-seed", kvm->cfg.arch.kaslr_seed));
> +	_FDT(fdt_property_string(fdt, "stdout-path", "/U6_16550A@3f8"));

Since the last string here has to match the one in hw/serial.c, I think we
should be retrieving it from there rather than hardcoding it here.

Will