Re: [PATCH 5/7] hw: Have machines Kconfig-select FW_CFG

[BALATON Zoltan]

On Mon, 26 Apr 2021, Philippe Mathieu-Daudé wrote:
> Beside the loongson3-virt machine (MIPS), the following machines
> also use the fw_cfg device:
>
> - ARM: virt & sbsa-ref
> - HPPA: generic machine
> - X86: ACPI based (pc & microvm)
> - PPC64: various
> - SPARC: sun4m & sun4u
>
> Add their FW_CFG Kconfig dependency.
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> ---
> hw/arm/Kconfig     | 2 ++
> hw/hppa/Kconfig    | 1 +
> hw/i386/Kconfig    | 2 ++
> hw/ppc/Kconfig     | 1 +
> hw/sparc/Kconfig   | 1 +
> hw/sparc64/Kconfig | 1 +
> 6 files changed, 8 insertions(+)
>
> diff --git a/hw/arm/Kconfig b/hw/arm/Kconfig
> index 8c37cf00da7..3b2641e39dc 100644
> --- a/hw/arm/Kconfig
> +++ b/hw/arm/Kconfig
> @@ -8,6 +8,7 @@ config ARM_VIRT
>     imply TPM_TIS_SYSBUS
>     select ARM_GIC
>     select ACPI
> +    select FW_CFG
>     select ARM_SMMUV3
>     select GPIO_KEY
>     select FW_CFG_DMA
> @@ -216,6 +217,7 @@ config SBSA_REF
>     select PL061 # GPIO
>     select USB_EHCI_SYSBUS
>     select WDT_SBSA
> +    select FW_CFG
>
> config SABRELITE
>     bool
> diff --git a/hw/hppa/Kconfig b/hw/hppa/Kconfig
> index 22948db0256..45f40e09224 100644
> --- a/hw/hppa/Kconfig
> +++ b/hw/hppa/Kconfig
> @@ -14,3 +14,4 @@ config DINO
>     select LASIPS2
>     select PARALLEL
>     select ARTIST
> +    select FW_CFG
> diff --git a/hw/i386/Kconfig b/hw/i386/Kconfig
> index 7f91f30877f..9e4039a2dce 100644
> --- a/hw/i386/Kconfig
> +++ b/hw/i386/Kconfig
> @@ -52,6 +52,7 @@ config PC_ACPI
>     select SMBUS_EEPROM
>     select PFLASH_CFI01
>     depends on ACPI_SMBUS
> +    select FW_CFG
>
> config I440FX
>     bool
> @@ -106,6 +107,7 @@ config MICROVM
>     select ACPI_HW_REDUCED
>     select PCI_EXPRESS_GENERIC_BRIDGE
>     select USB_XHCI_SYSBUS
> +    select FW_CFG
>
> config X86_IOMMU
>     bool
> diff --git a/hw/ppc/Kconfig b/hw/ppc/Kconfig
> index d11dc30509d..a7ba8283bf1 100644
> --- a/hw/ppc/Kconfig
> +++ b/hw/ppc/Kconfig
> @@ -131,6 +131,7 @@ config VIRTEX
> # Only used by 64-bit targets
> config FW_CFG_PPC
>     bool
> +    select FW_CFG

Why do we need a separate config option here if all it does is select 
FW_CFG and also in meson.build it only seems to add fw_cfg.c? (Unlike 
FW_CFG_DMA which seems to add other files so another option makes sense 
for that case). Could we just use FW_CFG directly and drop the PPC 
specific option like you did for MIPS?

Also the comment saying "Only used by 64-bit targets" seems to be wrong as 
it is also selected by MAC_OLDWORLD that's definitely a 32-bit machine 
(and MAC_NEWWORLD that can be both 32 or 64 bit) so maybe this option used 
to do something previously but now seems to be equivalent to just FW_CFG. 
So could it be dropped and use FW_CFG instead to simplify this or what's 
the reason to keep a PPC specific option for it?

Regards,
BALATON Zoltan

> config FDT_PPC
>     bool
> diff --git a/hw/sparc/Kconfig b/hw/sparc/Kconfig
> index 8dcb10086fd..267bf45fa21 100644
> --- a/hw/sparc/Kconfig
> +++ b/hw/sparc/Kconfig
> @@ -15,6 +15,7 @@ config SUN4M
>     select STP2000
>     select CHRP_NVRAM
>     select OR_IRQ
> +    select FW_CFG
>
> config LEON3
>     bool
> diff --git a/hw/sparc64/Kconfig b/hw/sparc64/Kconfig
> index 980a201bb73..c17b34b9d5b 100644
> --- a/hw/sparc64/Kconfig
> +++ b/hw/sparc64/Kconfig
> @@ -13,6 +13,7 @@ config SUN4U
>     select PCKBD
>     select SIMBA
>     select CHRP_NVRAM
> +    select FW_CFG
>
> config NIAGARA
>     bool