Re: [PULL 11/35] arm/Kconfig: Do not build TCG-only boards on a KVM-only build

[Thomas Huth <thuth@redhat.com>]

On 02/05/2023 14.14, Peter Maydell wrote:
> From: Fabiano Rosas <farosas@suse.de>
> 
> Move all the CONFIG_FOO=y from default.mak into "default y if TCG"
> statements in Kconfig. That way they won't be selected when
> CONFIG_TCG=n.
> 
> I'm leaving CONFIG_ARM_VIRT in default.mak because it allows us to
> keep the two default.mak files not empty and keep aarch64-default.mak
> including arm-default.mak. That way we don't surprise anyone that's
> used to altering these files.
> 
> With this change we can start building with --disable-tcg.
> 
> Signed-off-by: Fabiano Rosas <farosas@suse.de>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> Message-id: 20230426180013.14814-12-farosas@suse.de
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>   configs/devices/aarch64-softmmu/default.mak |  4 --
>   configs/devices/arm-softmmu/default.mak     | 37 ------------------
>   hw/arm/Kconfig                              | 42 ++++++++++++++++++++-
>   3 files changed, 41 insertions(+), 42 deletions(-)
> 
> diff --git a/configs/devices/aarch64-softmmu/default.mak b/configs/devices/aarch64-softmmu/default.mak
> index cf43ac8da11..70e05a197dc 100644
> --- a/configs/devices/aarch64-softmmu/default.mak
> +++ b/configs/devices/aarch64-softmmu/default.mak
> @@ -2,7 +2,3 @@
>   
>   # We support all the 32 bit boards so need all their config
>   include ../arm-softmmu/default.mak
> -
> -CONFIG_XLNX_ZYNQMP_ARM=y
> -CONFIG_XLNX_VERSAL=y
> -CONFIG_SBSA_REF=y
> diff --git a/configs/devices/arm-softmmu/default.mak b/configs/devices/arm-softmmu/default.mak
> index cb3e5aea657..647fbce88d3 100644
> --- a/configs/devices/arm-softmmu/default.mak
> +++ b/configs/devices/arm-softmmu/default.mak
> @@ -4,40 +4,3 @@
>   # CONFIG_TEST_DEVICES=n
>   
>   CONFIG_ARM_VIRT=y
> -CONFIG_CUBIEBOARD=y
> -CONFIG_EXYNOS4=y
> -CONFIG_HIGHBANK=y
> -CONFIG_INTEGRATOR=y
> -CONFIG_FSL_IMX31=y
> -CONFIG_MUSICPAL=y
> -CONFIG_MUSCA=y
> -CONFIG_CHEETAH=y
> -CONFIG_SX1=y
> -CONFIG_NSERIES=y
> -CONFIG_STELLARIS=y
> -CONFIG_STM32VLDISCOVERY=y
> -CONFIG_REALVIEW=y
> -CONFIG_VERSATILE=y
> -CONFIG_VEXPRESS=y
> -CONFIG_ZYNQ=y
> -CONFIG_MAINSTONE=y
> -CONFIG_GUMSTIX=y
> -CONFIG_SPITZ=y
> -CONFIG_TOSA=y
> -CONFIG_Z2=y
> -CONFIG_NPCM7XX=y
> -CONFIG_COLLIE=y
> -CONFIG_ASPEED_SOC=y
> -CONFIG_NETDUINO2=y
> -CONFIG_NETDUINOPLUS2=y
> -CONFIG_OLIMEX_STM32_H405=y
> -CONFIG_MPS2=y
> -CONFIG_RASPI=y
> -CONFIG_DIGIC=y
> -CONFIG_SABRELITE=y
> -CONFIG_EMCRAFT_SF2=y
> -CONFIG_MICROBIT=y
> -CONFIG_FSL_IMX25=y
> -CONFIG_FSL_IMX7=y
> -CONFIG_FSL_IMX6UL=y
> -CONFIG_ALLWINNER_H3=y
> diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
> index 87c1a29c912..2d7c4579559 100644
> --- a/hw/arm/Kconfig
> +++ b/hw/arm/Kconfig
> @@ -35,20 +35,24 @@ config ARM_VIRT
>   
>   config CHEETAH
>       bool
> +    default y if TCG && ARM
>       select OMAP
>       select TSC210X
>   
>   config CUBIEBOARD
>       bool
> +    default y if TCG && ARM
>       select ALLWINNER_A10
...

  Hi!

Sorry for not noticing this earlier, but I have to say that I really dislike 
this change, since it very much changes the way we did our machine 
configuration so far.
Until now, you could simply go to configs/devices/*-softmmu/*.mak and only 
select the machines you wanted to have with "...=y" and delete everything 
else. Now you have to know *all* the machines that you do *not* want to have 
in your build and disable them with "...=n" in that file. That's quite ugly, 
especially for the arm target that has so many machines. (ok, you could also 
do a "--without-default-devices" configuration to get rid of the machines, 
but that also disables all other kind of devices that you then have to 
specify manually).

Isn't there a better way to solve this TCG dependency problem?
Paolo, do you maybe have any ideas?

  Thomas