| Message ID | cover.1739525488.git.geert+renesas@glider.be (mailing list archive) |
|---|---|
| Headers | show |
| Series | ARM: dts: renesas: r9a06g032: UART dtbs_check fixes | expand |
+CC Ralph Siemsen <ralph.siemsen@linaro.org> who has RZ/N1 board. > -----Original Message----- > From: Geert Uytterhoeven <geert+renesas@glider.be> > Sent: 14 February 2025 09:42 > To: Magnus Damm <magnus.damm@gmail.com>; Wolfram Sang <wsa+renesas@sang-engineering.com>; Miquel > Raynal <miquel.raynal@bootlin.com> > Cc: linux-renesas-soc@vger.kernel.org; linux-arm-kernel@lists.infradead.org; > devicetree@vger.kernel.org; Geert Uytterhoeven <geert+renesas@glider.be> > Subject: [PATCH 0/2] ARM: dts: renesas: r9a06g032: UART dtbs_check fixes > > Hi all, > > This patch series fixes two "make dtbs_check" issues for the RZ/N1 UARTs. As I do not have access to > an RZ/N1 board, this was not tested on actual hardware. Adding Ralph Siemsen <ralph.siemsen@linaro.org> who has RZ/N1 board. Cheers, Biju > > Thanks for your comments! > > Geert Uytterhoeven (2): > ARM: dts: renesas: r9a06g032: Fix UART dma channel order > ARM: dts: renesas: r9a06g032: Drop snps,dw-apb-uart compatibility > > arch/arm/boot/dts/renesas/r9a06g032.dtsi | 26 ++++++++++++------------ > 1 file changed, 13 insertions(+), 13 deletions(-) > > -- > 2.43.0 > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But when I'm talking to > journalists I just say "programmer" or something like that. > -- Linus Torvalds
Hello Geert, On 14/02/2025 at 10:42:04 +01, Geert Uytterhoeven <geert+renesas@glider.be> wrote: > make dtbs_check: > > arch/arm/boot/dts/renesas/r9a06g032-rzn1d400-db.dtb: serial@40060000: compatible: 'oneOf' conditional failed, one must be fixed: > ['renesas,r9a06g032-uart', 'renesas,rzn1-uart', 'snps,dw-apb-uart'] is too long > ... > > As per commit 72b0505f0830df95 ("dt: serial: Add Renesas RZ/N1 binding > documentation"), the RZ/N1 UART is a modified Synopsys DesignWare UART. > The modifications only relate to DMA, so you could actually use the > controller with the Synopsys compatible string if you are not using DMA, > but you should not do so. Hence the first three UARTs (which don't > support DMA) were added with a "snps,dw-apb-uart" fallback, to use the > existing Synopsys DesignWare UART support. > > Since support for the RZ/N1-specific compatible value was added to the > driver a long time ago (commit 2ff5fa7f742ab0c6 ("serial: 8250_dw: Add > compatible string for Renesas RZ/N1 UART") in v4.19), the extra > compatible value can be dropped safely. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> > --- > Alternatively, the bindings[1] could be augmented with an extra section: > > - items: > - enum: > - renesas,r9a06g032-uart > - renesas,r9a06g033-uart > - const: renesas,rzn1-uart > - const: snps,dw-apb-uart # RZ/N1 without DMA > > and perhaps extra logic to prohibit the dmas property when both > renesas,rzn1-uart and snps,dw-apb-uart are present. I must say that I prefer this secondary approach, which feels more accurate. I won't block the one that your proposed below for sure, but I feel like it is more relevant to add this third entry in the bindings rather than removing it from the DT. Either way, fine by me. > > Given the complexity of the latter, I went for the simple solution. > > [1] Documentation/devicetree/bindings/serial/snps-dw-apb-uart.yaml Thanks, Miquèl