Re: [PATCH] dtc

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

Oops, wrong subject.

On 6/10/23 08:45, Philippe Mathieu-Daudé wrote:
> QEMU consumes some device tree blobs, so these have been committed
> to the tree in as firmware, along with the device tree source used
> to generate them. We know the blobs are "good enough" to have QEMU
> boot a system, so we don't really maintain and rebuild the sources.
> 
> These blobs were generated with older 'dtc' binaries. We use the
> v1.6.1 version since 2021 (commit 962fde57b7 "dtc: Update to version
> 1.6.1").
> 
> Since commit 6e0dc9d2a8 ("meson: compile bundled device trees"),
> if dtc binary is available, it is directly used to compile the
> device tree sources. New versions of 'dtc' add checks which display
> warnings or errors. Our sources are a bit old, so dtc v1.6.1 now
> emit the following warnings on a fresh build:
> 
>    [163/3414] Generating pc-bios/canyonlands.dts with a custom command
>    pc-bios/canyonlands.dts:47.9-50.4: Warning (unit_address_vs_reg): /memory: node has a reg or ranges property, but no unit name
>    pc-bios/canyonlands.dts:210.13-429.5: Warning (unit_address_vs_reg): /plb/opb: node has a reg or ranges property, but no unit name
>    pc-bios/canyonlands.dts:464.26-504.5: Warning (pci_bridge): /plb/pciex@d00000000: node name is not "pci" or "pcie"
>    pc-bios/canyonlands.dts:506.26-546.5: Warning (pci_bridge): /plb/pciex@d20000000: node name is not "pci" or "pcie"
>    pc-bios/canyonlands.dtb: Warning (unit_address_format): Failed prerequisite 'pci_bridge'
>    pc-bios/canyonlands.dtb: Warning (pci_device_reg): Failed prerequisite 'pci_bridge'
>    pc-bios/canyonlands.dtb: Warning (pci_device_bus_num): Failed prerequisite 'pci_bridge'
>    pc-bios/canyonlands.dts:268.14-289.7: Warning (avoid_unnecessary_addr_size): /plb/opb/ebc/ndfc@3,0: unnecessary #address-cells/#size-cells without "ranges" or child "reg" property
>    [164/3414] Generating pc-bios/petalogix-s3adsp1800.dts with a custom command
>    pc-bios/petalogix-s3adsp1800.dts:258.33-266.5: Warning (interrupt_provider): /plb/interrupt-controller@81800000: Missing #address-cells in interrupt provider
>    [165/3414] Generating pc-bios/petalogix-ml605.dts with a custom command
>    pc-bios/petalogix-ml605.dts:234.39-241.5: Warning (interrupt_provider): /axi/interrupt-controller@81800000: Missing #address-cells in interrupt provider
>    [177/3414] Generating pc-bios/bamboo.dts with a custom command
>    pc-bios/bamboo.dts:45.9-48.4: Warning (unit_address_vs_reg): /memory: node has a reg or ranges property, but no unit name
>    pc-bios/bamboo.dts:87.13-154.5: Warning (unit_address_vs_reg): /plb/opb: node has a reg or ranges property, but no unit name
>    pc-bios/bamboo.dts:198.3-50: Warning (chosen_node_stdout_path): /chosen:linux,stdout-path: Use 'stdout-path' instead
>    pc-bios/bamboo.dts:87.13-154.5: Warning (interrupts_property): /plb/opb: Missing interrupt-parent
>    pc-bios/bamboo.dts:100.14-108.6: Warning (interrupts_property): /plb/opb/ebc: Missing interrupt-parent
> 
>  From QEMU perspective, these warnings are not really useful. It is
> the responsibility of developers adding DT source/blob to QEMU
> repository to check the source doesn't produce warnings, but as
> long as the blob is useful enough, QEMU can consume it. So these
> warnings don't add any value, instead they are noisy and might
> distract us to focus on important warnings. Better disable them.
> 
> 'dtc' provides the '--quiet' option for that:
> 
>    $ dtc --help
>    Usage: dtc [options] <input file>
> 
>    Options: -[qI:O:o:V:d:R:S:p:a:fb:i:H:sW:E:@AThv]
>      -q, --quiet
>            Quiet: -q suppress warnings, -qq errors, -qqq all
> 
> Update meson to disable these unuseful DTC warnings.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
> Note, meson outputs "Generating dts" instead of "Generating dtb".
> ---
>   pc-bios/meson.build | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/pc-bios/meson.build b/pc-bios/meson.build
> index e67fa433a1..162663fed6 100644
> --- a/pc-bios/meson.build
> +++ b/pc-bios/meson.build
> @@ -95,7 +95,8 @@ foreach f : [
>           output: out,
>           install: get_option('install_blobs'),
>           install_dir: qemu_datadir,
> -        command: [ dtc, '-I', 'dts', '-O', 'dtb', '-o', '@OUTPUT@', '@INPUT0@' ])
> +        command: [ dtc, '-q', '-I', 'dts', '-O', 'dtb',
> +                        '-o', '@OUTPUT@', '@INPUT0@' ])
>     else
>       blobs += out
>     endif