[PATCH net-next v3 3/5] net: stmmac: sun55i: Make the delay step configurable

Jerome Brunet jbrunet at baylibre.com
Thu Sep 24 01:53:59 PDT 2026


On jeu. 24 sept. 2026 at 04:30, Andrew Lunn <andrew at lunn.ch> wrote:

>> +	 * Correcting them would break the DT ABI of the published DTs.
>> +	 */
>> +	.txdly_step_ps = 100,
>> +	.rxdly_step_ps = 100,
>
> Could you be a bit more specific about what published means?

DTs like those ones:
* https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/allwinner/sun55i-a527-cubie-a5e.dts?h=v7.3-rc4#n88
* https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/allwinner/sun55i-t527-avaota-a1.dts?h=v7.3-rc4#n87
* https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/allwinner/sun55i-t527-orangepi-4a.dts?h=v7.3-rc4#n106

On A523/T527, only gmac1 is supported by the driver addressed in this
series. gmac0 is another (dwmac) driver.

If I take the 1st example

&gmac1 {
	phy-mode = "rgmii-id";
	phy-handle = <&ext_rgmii1_phy>;
	phy-supply = <&reg_cldo4>;

	tx-internal-delay-ps = <300>;
	rx-internal-delay-ps = <400>;

	status = "okay";
};

If the information we've got about the A523 delay steps are correct, the
actual values would be:
* tx: 540ps
* rx: 2120ps

So I suppose in this case, the phy-mode is more likely to be rgmii-txid,
isn't it ?

>
>       Andrew

-- 
Jerome



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