Am 27.03.24 um 16:55 schrieb Christian Gmeiner:
> Hi Josua
>
>>> Hi Josua
>>>
>>> My bisect showed me that after a device-tree sync the ethernet broke.
>>>
>>>> please take a look at this patch, I suspect it will (hack-)fix your
>>>> ethernet issue.
>>>>
>>> Yes.. it fixes the problem I am seeing.
>>>
>>>> Unfortunately I had no time to revisit this yet and implement a correct
>>>> solution.
>>>>
>>> Would it be okay for you if I look into a proper solution?
>> Sure. I am swamped by other products at the moment.
>>
>> However I will provide a rough overview what needs to be done:
>>
>> Background: i.MX6 SoMs originally had a an atheros phy at unstable address,
>> either 0 or 4 depending on electrical noise on floating configuration
>> signals.
>>
> Would it be possible to set those configuration signals from the MX6
> to a defined state and
> then toggle the PHY reset , to force correct PHY address?
There is no cpu control over the signals responsible for phy address.
>
>> Linux had solved this by placing 2 phy nodes in device-tree.
>> During boot the kernel would attempt in order to probe the phys,
>> then link the successful one to the ethernet netdev.
>> As a side-effect there is always an error in the kernel log for one of the
>> addresses.
>>
>> U-Boot had something similar in that with a special address (I think 0xff)
>> in device-tree, the code will probe mdio bus for all addresses, but only
>> for a single phy node in dts.
>>
>> With release of SoM 2.0 we changed to an analog devices phy at address 1,
>> which most importantly uses a different driver, and requires a different
>> description
>> in device-tree.
>>
>> When adding this new phy, as a third node in device-tree, kernel maintainers
>> requested a better solution, and we got u-boot to runtime patch dtb to update
>> status properties of the dtb for linux, after probing mdio bus for phys.
>>
> Got it.
>
>> Now - what u-boot needs to do is probe the mdio bus, and then runtime-patch
>> its own DTB.
>> Either with status properties, or for adding the phy-handle property (not
>> sure which method will work).
>>
> We could patch DTB in SPL for U-Boot proper but doing a mdio scan in
> SPL looks like a lot of work.
In SPL I agree this would be quite painful.
Maybe it can be done in u-boot proper, at the right moment.
We basically need to intersept the place where ethernet (controller?) driver
is looking for the phy-handle property or probing a phy.
Maybe there is already a call-back for board-specific code,
or one could be added.
> Do
> you know if there is a pull up/down resistor etc. that I could use to
> detect pre SoM 2.0 and SoM 2.0?
>
> Is this what board_type() does?
> Is HummingBoard2 == SoM 2.0?
No, this is carrier-board detection.
For the SoM we have nothing.
PHY mdio address is actually the best indication we have.
>
>> This somehow has to happen after probing mdio driver, but before probing
>> ethernet driver.
>>
>>> I have a
>>> handful of such devices here
>>> that are already or will be used in a CI farm so I am interested in
>>> using the latest U-Boot for them.
>>>
>>>> sincerely
>>>> Josua Mayer
>>>>
>>>> Am 28.07.22 um 09:08 schrieb Josua Mayer:
>>>>> Please hold off merging this patch until someone tested it, I can not do
>>>>> so this week.
>>>>> @Tom Can you confirm if this fixes the networking on your Cubox?
>>>>> Also note that the phy-handle property may or may not be required, I am
>>>>> not sure.
>>>>>
>>>>> sincerely
>>>>> Josua Mayer
>>>>>
>>>>> On Thu, Jul 28, 2022 at 7:05 AM Josua Mayer <jo...@solid-run.com> wrote:
>>>>>
>>>>> The i.MX6 Cubox-i and HummingBoards can have different PHYs at varying
>>>>> addresses. U-Boot needs to auto-detect which phy is actually present,
>>>>> and at which address it is responding.
>>>>>
>>>>> Auto-detection from multiple phy nodes specified in device-tree does
>>>>> not
>>>>> currently work correct. As a work-around merge all three possible phys
>>>>> into one node with the special address 0xffffffff which indicates to
>>>>> the
>>>>> generic phy driver to probe all addresses.
>>>>> Also fixup this fake address before booting Linux, *if* booting with
>>>>> U-Boot's internal dtb.
>>>>>
>>>>> Signed-off-by: Josua Mayer <jo...@solid-run.com>
>>>>> Fixes: d0399a46e7cd
>>>>> ---
>>>>> arch/arm/dts/imx6qdl-sr-som.dtsi | 30
>>>>> +++++++++-------------------
>>>>> board/solidrun/mx6cuboxi/mx6cuboxi.c | 6 +++++-
>>>>> 2 files changed, 14 insertions(+), 22 deletions(-)
>>>>>
>>>>> diff --git a/arch/arm/dts/imx6qdl-sr-som.dtsi
>>>>> b/arch/arm/dts/imx6qdl-sr-som.dtsi
>>>>> index ce543e325c..2d7cbc26b3 100644
>>>>> ---_a/arch/arm/dts/imx6qdl-sr-som.dtsi
>>>>> +++ b/arch/arm/dts/imx6qdl-sr-som.dtsi
>>>>> @@ -53,6 +53,7 @@
>>>>> &fec {
>>>>> pinctrl-names = "default";
>>>>> pinctrl-0 = <&pinctrl_microsom_enet_ar8035>;
>>>>> + phy-handle = <&phy>;
>>>>> phy-mode = "rgmii-id";
>>>>>
>>>>> /*
>>>>> @@ -68,30 +69,17 @@
>>>>> #address-cells = <1>;
>>>>> #size-cells = <0>;
>>>>>
>>>>> - /*
>>>>> - * The PHY can appear at either address 0 or 4 due to
>>>>> the
>>>>> - * configuration (LED) pin not being pulled
>>>>> sufficiently.
>>>>> - */
>>>>> - ethernet-phy@0 {
>>>>> - reg = <0>;
>>>>> + phy: ethernet-phy@0 {
>>>>> + /*
>>>>> + * The PHY can appear either:
>>>>> + * - AR8035: at address 0 or 4
>>>>> + * - ADIN1300: at address 1
>>>>> + * Actual address being detected at runtime.
>>>>> + */
>>>>> + reg = <0xffffffff>;
>>>>> qca,clk-out-frequency = <125000000>;
>>>>> qca,smarteee-tw-us-1g = <24>;
>>>>> - };
>>>>> -
>>>>> - ethernet-phy@4 {
>>>>> - reg = <4>;
>>>>> - qca,clk-out-frequency = <125000000>;
>>>>> - qca,smarteee-tw-us-1g = <24>;
>>>>> - };
>>>>> -
>>>>> - /*
>>>>> - * ADIN1300 (som rev 1.9 or later) is always at
>>>>> address 1. It
>>>>> - * will be enabled automatically by U-Boot if
>>>>> detected.
>>>>> - */
>>>>> - ethernet-phy@1 {
>>>>> - reg = <1>;
>>>>> adi,phy-output-clock = "125mhz-free-running";
>>>>> - status = "disabled";
>>>>> };
>>>>> };
>>>>> };
>>>>> diff --git a/board/solidrun/mx6cuboxi/mx6cuboxi.c
>>>>> b/board/solidrun/mx6cuboxi/mx6cuboxi.c
>>>>> index debf4f6a3b..52172a03b1 100644
>>>>> ---_a/board/solidrun/mx6cuboxi/mx6cuboxi.c
>>>>> +++ b/board/solidrun/mx6cuboxi/mx6cuboxi.c
>>>>> @@ -446,7 +446,7 @@ static int find_ethernet_phy(void)
>>>>> */
>>>>> int ft_board_setup(void *fdt, struct bd_info *bd)
>>>>> {
>>>>> - int node_phy0, node_phy1, node_phy4;
>>>>> + int node_phy, node_phy0, node_phy1, node_phy4;
>>>>> int ret, phy;
>>>>> bool enable_phy0 = false, enable_phy1 = false, enable_phy4 =
>>>>> false;
>>>>> enum board_type board;
>>>>> @@ -478,6 +478,10 @@ int ft_board_setup(void *fdt, struct bd_info *bd)
>>>>> return 0;
>>>>> }
>>>>>
>>>>> + // update U-Boot's own unified phy node phy address, if
>>>>> present
>>>>> + node_phy = fdt_path_offset(fdt,
>>>>> "/soc/bus@2100000/ethernet@2188000/mdio/phy");
>>>>> + ret = fdt_setprop_u32(fdt, node_phy, "reg", phy);
>>>>> +
>>>>> // update all phy nodes status
>>>>> node_phy0 = fdt_path_offset(fdt,
>>>>> "/soc/bus@2100000/ethernet@2188000/mdio/ethernet-phy@0");
>>>>> ret = fdt_setprop_string(fdt, node_phy0, "status",
>>>>> enable_phy0 ? "okay" : "disabled");
>>>>> --_
>>>>> 2.37.1
>>>>>
>
>
