On Fri, Dec 03, 2021 at 08:35:17PM +0200, Sam Protsenko wrote:
> There are valid cases when two nodes can have the same address. For
> example, in Exynos SoCs there is USI IP-core, which might be configured
> to provide UART, SPI or I2C block, all of which having the same base
> register address. But only one can be enabled at a time. That looks like
> this:
>
> usi@138200c0 {
> serial@13820000 {
> status = "okay";
> };
>
> i2c@13820000 {
> status = "disabled";
> };
> };
>
> When running "make dt_binding_check", it reports next warning:
>
> Warning (unique_unit_address):
> /example-0/usi@138200c0/serial@13820000:
> duplicate unit-address (also used in node
> /example-0/usi@138200c0/i2c@13820000)
>
> Disable "unique_unit_address" in DTC_FLAGS to suppress warnings like
> that, but enable "unique_unit_address_if_enabled" warning, so that dtc
> still reports a warning when two enabled nodes are having the same
> address.
Presumably you have a dts file needing the same thing, so I'll be
expecting a patch for that too. That's in scripts/Makefile.lib BTW.
>
> Signed-off-by: Sam Protsenko <semen.protsenko@xxxxxxxxxx>
> Reported-by: Rob Herring <robh@xxxxxxxxxx>
> Suggested-by: Rob Herring <robh@xxxxxxxxxx>
> ---
> Documentation/devicetree/bindings/Makefile | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/Makefile b/Documentation/devicetree/bindings/Makefile
> index c9abfbe3f0aa..41c555181b6f 100644
> --- a/Documentation/devicetree/bindings/Makefile
> +++ b/Documentation/devicetree/bindings/Makefile
> @@ -65,7 +65,9 @@ DT_DOCS = $(patsubst $(srctree)/%,%,$(shell $(find_all_cmd)))
> override DTC_FLAGS := \
> -Wno-avoid_unnecessary_addr_size \
> -Wno-graph_child_address \
> - -Wno-interrupt_provider
> + -Wno-interrupt_provider \
> + -Wno-unique_unit_address \
> + -Wunique_unit_address_if_enabled
>
> # Disable undocumented compatible checks until warning free
> override DT_CHECKER_FLAGS ?=
> --
> 2.30.2
>
>
