Re: [RFC PATCH 3/5] hw/ppc: Have pSeries depends on libfdt (via host Kconfig FDT symbol)

[Paolo Bonzini]

On 11/05/21 17:53, Philippe Mathieu-Daudé wrote:
> Since commit fea35ca4b8e ("ppc/spapr: Receive and store device
> tree blob from SLOF") the pSeries machine depends on the libfdt
> fdt_check_full() call, which is available in libfdt v1.4.7.
>
> Add the corresponding Kconfig dependency.
>
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>

This is not the only one though.  In particular, there should be a 
"depends on" also for MIPS_BOSTON (hw/mips), E500 (hw/ppc), POWERNV, 
PPC440 (hw/ppc), (hw/ppc), SAM460EX (hw/ppc), VIRTEX (hw/ppc), RX_GDBSIM 
(hw/rx), XTENSA_XTFPGA (hw/xtensa).

Once you do this, TARGET_NEED_FDT can go away for PPC, MIPS and.  The 
remaining ones use fdt functions in hw/*/boot.c so they need libfdt 
unconditionally RX (and TARGET_NEED_FDT should be added to 
default-configs/targets/nios2-softmmu.mak for the same reason).

Paolo

> ---
>   hw/ppc/Kconfig     | 1 +
>   hw/ppc/meson.build | 4 ++--
>   2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/hw/ppc/Kconfig b/hw/ppc/Kconfig
> index 66e0b15d9ef..3935b73456f 100644
> --- a/hw/ppc/Kconfig
> +++ b/hw/ppc/Kconfig
> @@ -1,5 +1,6 @@
>   config PSERIES
>       bool
> +    depends on FDT
>       imply PCI_DEVICES
>       imply TEST_DEVICES
>       imply VIRTIO_VGA
> diff --git a/hw/ppc/meson.build b/hw/ppc/meson.build
> index 86d6f379d1c..e82a6b4105b 100644
> --- a/hw/ppc/meson.build
> +++ b/hw/ppc/meson.build
> @@ -9,7 +9,7 @@
>   ppc_ss.add(when: 'CONFIG_FW_CFG_PPC', if_true: files('fw_cfg.c'))
>   
>   # IBM pSeries (sPAPR)
> -ppc_ss.add(when: 'CONFIG_PSERIES', if_true: files(
> +ppc_ss.add(when: 'CONFIG_PSERIES', if_true: [files(
>     'spapr.c',
>     'spapr_caps.c',
>     'spapr_vio.c',
> @@ -28,7 +28,7 @@
>     'spapr_rtas_ddw.c',
>     'spapr_numa.c',
>     'pef.c',
> -))
> +), fdt])
>   ppc_ss.add(when: 'CONFIG_SPAPR_RNG', if_true: files('spapr_rng.c'))
>   ppc_ss.add(when: ['CONFIG_PSERIES', 'CONFIG_LINUX'], if_true: files(
>     'spapr_pci_vfio.c',