Hi Sergey, On Tue, Jun 21, 2022 at 3:12 AM Serge Semin <fancer.lancer@xxxxxxxxx> wrote: > > On Tue, Jun 21, 2022 at 09:00:36AM +0200, Krzysztof Kozlowski wrote: > > On 20/06/2022 22:04, Serge Semin wrote: > > > On Mon, Jun 20, 2022 at 09:46:25PM +0200, Krzysztof Kozlowski wrote: > > >> On 20/06/2022 21:30, Serge Semin wrote: > > >>> On Mon, Jun 13, 2022 at 12:56:47PM -0700, Brad Larson wrote: > > >>>> From: Brad Larson <blarson@xxxxxxx> > > >>>> > > >>>> The AMD Pensando Elba SoC has integrated the DW APB SPI Controller > > >>>> > > >>>> Signed-off-by: Brad Larson <blarson@xxxxxxx> > > >>>> --- > > >>>> Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml | 2 ++ > > >>>> 1 file changed, 2 insertions(+) > > >>>> > > >>>> diff --git a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml > > >>>> index e25d44c218f2..2a55b947cffc 100644 > > >>>> --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml > > >>>> +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml > > >>>> @@ -73,6 +73,8 @@ properties: > > >>>> - renesas,r9a06g032-spi # RZ/N1D > > >>>> - renesas,r9a06g033-spi # RZ/N1S > > >>>> - const: renesas,rzn1-spi # RZ/N1 > > >>> > > >>>> + - description: AMD Pensando Elba SoC SPI Controller > > >>>> + const: amd,pensando-elba-spi > > >>> > > >>> Not enough. The driver requires to have a phandle reference to the > > >>> Pensando System Controller. So the property like > > >>> "amd,pensando-elba-syscon" is also needed to be added to the DT schema > > >>> otherwise should the dt-schema tool correctly handle the > > >>> "unevaluatedProperties: false" setting (Rob says it isn't fully > > >>> supported at the moment), the dtbs_check procedure will fail on your > > >>> dts evaluation. > > >> > > > > > >> The property was here before, now removed, so I assume it was also > > >> removed from the driver and DTS. Isn't that the case? > > > > > > Ah, the property has been indeed removed. The driver now searches for > > > the system controller by the next compatible string: > > > "amd,pensando-elba-syscon" using the > > > syscon_regmap_lookup_by_compatible() method. My mistake. Sorry for the > > > noise. > > > > > > > * Though personally I'd prefer to have a property with the phandle > > > reference in order to signify the connection between the system controller > > > and the SPI-controller. Otherwise the implicit DT bindings like having > > > the "amd,pensando-elba-syscon"-compatible syscon gets to be > > > hidden behind the DT scene. But seeing we have already got the Microsemi > > > platform with such semantic, I can't insist on fixing this. > > > > I agree entirely, this should be explicit syscon-type property. Looking > > up for compatibles: > > - creates hidden (not expressed via bindings) dependency between nodes, > > - is not portable and several people struggled with it later and needed > > backward-compatible code (many examples, let's just give recent one: [1]) > > > > > > [1] > > https://lore.kernel.org/all/20220619151225.209029-10-tmaimon77@xxxxxxxxx/ > > Seems even more reasonable now. Thanks for providing a bright example > justifying the property-based approach. > > @Brad, could you get back the property with a phandle to the syscon > DT-node? (No need in adding the CS CSR address as the phandle argument, > just a phandle.) Replying to the sequence of review inputs. The below change to version 5 brings back the phandle without the earlier argument that complicated the binding (was the motivation for moving in this direction in earlier version). Passes dtbs_check. --- a/drivers/spi/spi-dw-mmio.c +++ b/drivers/spi/spi-dw-mmio.c @@ -285,12 +285,17 @@ static void dw_spi_elba_set_cs(struct spi_device *spi, bool enable) static int dw_spi_elba_init(struct platform_device *pdev, struct dw_spi_mmio *dwsmmio) { + struct device_node *np = pdev->dev.of_node; + struct device_node *node; struct dw_spi_elba *dwselba; struct regmap *regmap; - regmap = syscon_regmap_lookup_by_compatible("amd,pensando-elba-syscon"); - if (IS_ERR(regmap)) - return PTR_ERR(regmap); + node = of_parse_phandle(np, "pensando,elba-syscon-spics", 0); + if (node) { + regmap = syscon_node_to_regmap(node); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + } diff --git a/arch/arm64/boot/dts/amd/elba.dtsi b/arch/arm64/boot/dts/amd/elba.dtsi index 9739641261c3..ec48be4cfe48 100644 --- a/arch/arm64/boot/dts/amd/elba.dtsi +++ b/arch/arm64/boot/dts/amd/elba.dtsi @@ -98,6 +98,7 @@ reg = <0x0 0x2800 0x0 0x100>; #address-cells = <1>; #size-cells = <0>; + pensando,elba-syscon-spics = <&syscon>; clocks = <&ahb_clk>; interrupts = <GIC_SPI 9 IRQ_TYPE_LEVEL_HIGH>; num-cs = <2>; --- a/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml +++ b/Documentation/devicetree/bindings/spi/snps,dw-apb-ssi.yaml @@ -37,6 +37,15 @@ allOf: else: required: - interrupts + - if: + properties: + compatible: + contains: + enum: + - amd,pensando-elba-spi + then: + required: + - pensando,elba-syscon-spics properties: compatible: Regards, Brad