[PATCH v5 2/2] arm64: dts: rockchip: add support for Radxa ROCK Pi E v3.0

[FUKAUMI Naoki]

Hi,

RFC:
https://patchwork.ozlabs.org/project/uboot/patch/20240827013111.633-1-naoki@radxa.com/

Best regards,

--
FUKAUMI Naoki
Radxa Computer (Shenzhen) Co., Ltd.

On 8/27/24 08:20, FUKAUMI Naoki wrote:
> Hi,
> 
> On 8/26/24 20:25, Dragan Simic wrote:
>> Hello Naoki,
>>
>> On 2024-08-18 00:30, Dragan Simic wrote:
>>> On 2024-08-17 22:28, FUKAUMI Naoki wrote:
>>>> On 8/18/24 05:12, Dragan Simic wrote:
>>>>> On 2024-08-17 22:04, FUKAUMI Naoki wrote:
>>>>>> On 8/18/24 04:51, Dragan Simic wrote:
>>>>>>> On 2024-08-17 21:28, Dragan Simic wrote:
>>>>>>>> On 2024-08-17 00:20, FUKAUMI Naoki wrote:
>>>>>>>>> On 8/17/24 07:11, Heiko Stübner wrote:
>>>>>>>>>> Am Freitag, 16. August 2024, 23:34:29 CEST schrieb FUKAUMI Naoki:
>>>>>>>>>>> Radxa ROCK Pi E v3.0 is a compact networking SBC[1] using the 
>>>>>>>>>>> Rockchip
>>>>>>>>>>> RK3328 chip that ships in a number of RAM/eMMC/WiFi/BT 
>>>>>>>>>>> configurations:
>>>>>>>>>>>
>>>>>>>>>>> - Rockchip RK3328 SoC
>>>>>>>>>>> - Quad A53 CPU
>>>>>>>>>>> - 512MB/1GB/2GB DDR4 RAM
>>>>>>>>> (snip)
>>>>>>>>>> can you please describe what is different in that v3 board?
>>>>>>>>>> Describing what is different to require a separate board 
>>>>>>>>>> should've been
>>>>>>>>>> part of the commit message.
>>>>>>>>>>
>>>>>>>>>> Because from those changes, the bottom line currently seems to be
>>>>>>>>>> the same board with swapped mmc aliases?
>>>>>>>>>
>>>>>>>>> it's new board which uses DDR4 RAM (instead of DDR3 RAM on Pi E).
>>>>>>>>> different bootloader (U-Boot) is required.
>>>>>>>>>
>>>>>>>>> adding v3 dts seems not to be so important for Linux, but it's 
>>>>>>>>> very
>>>>>>>>> important for U-Boot and OpenWrt(it includes bootloader for
>>>>>>>>> distributed binary).
>>>>>>>>
>>>>>>>> Aren't there different methods that allow such board variants to be
>>>>>>>> supported in U-Boot, with no need for a separate DT in the kernel?
>>>>>>>> IIRC, there are already more than a few examples of such board 
>>>>>>>> variants,
>>>>>>>> which require different DRAM initialization, which is covered in 
>>>>>>>> U-Boot
>>>>>>>> by providing different builds that use the same DT.
>>>>>>>
>>>>>>> As an example, please have a look at the following files in U-Boot:
>>>>>>>
>>>>>>> - arch/arm/dts/rk3399-nanopi-m4-u-boot.dtsi
>>>>>>> - arch/arm/dts/rk3399-nanopi-m4-2gb-u-boot.dtsi
>>>>>>> - configs/nanopi-m4-rk3399_defconfig
>>>>>>> - configs/nanopi-m4-2gb-rk3399_defconfig
>>>>>>>
>>>>>>> Basically, there's no need for separate DTs in the kernel, just 
>>>>>>> to support
>>>>>>> board variants with different DRAM types in U-Boot.
>>>>>>
>>>>>> OpenWrt firmware upgrading tool (sysupgrade) refers "compatible"
>>>>>> string to validate new firmware file is surely "for this board".
>>>>>>
>>>>>> currently both Pi E dts have "radxa,rockpi-e", it makes flashing 
>>>>>> wrong
>>>>>> firmware (include bootloaer, U-Boot) possible.
>>>>>
>>>>> Could you, please, explain what's the actual issue with OpenWrt?  I 
>>>>> did
>>>>> read some GitHub issue that described it, IIRC, but I was unable to 
>>>>> fully
>>>>> understand what's the underlying issue.
>>>>
>>>> $ wget
>>>> https://downloads.openwrt.org/snapshots/targets/rockchip/armv8/openwrt-rockchip-armv8-radxa_rock-pi-e-ext4-sysupgrade.img.gz
>>>> $ strings
>>>> openwrt-rockchip-armv8-radxa_rock-pi-e-ext4-sysupgrade.img.gz | grep
>>>> metadata
>>>> {  "metadata_version": "1.1", "compat_version": "1.0",
>>>> "supported_devices":["radxa,rock-pi-e"], "version": { "dist":
>>>> "OpenWrt", "version": "SNAPSHOT", "revision": "r27160-b72c4b5386",
>>>> "target": "rockchip/armv8", "board": "radxa_rock-pi-e" } }
>>>>
>>>> $ wget
>>>> https://downloads.openwrt.org/snapshots/targets/rockchip/armv8/openwrt-rockchip-armv8-radxa_rock-pi-e-v3-ext4-sysupgrade.img.gz
>>>> $ strings
>>>> openwrt-rockchip-armv8-radxa_rock-pi-e-v3-ext4-sysupgrade.img.gz |
>>>> grep metadata
>>>> {  "metadata_version": "1.1", "compat_version": "1.0",
>>>> "supported_devices":["radxa,rock-pi-e-v3"], "version": { "dist":
>>>> "OpenWrt", "version": "SNAPSHOT", "revision": "r27160-b72c4b5386",
>>>> "target": "rockchip/armv8", "board": "radxa_rock-pi-e-v3" } }
>>>>
>>>> since they are incompatible firmware, it needs to have different
>>>> "supported_devices" string. if both are "radxa,rockpi-e", firmware
>>>> validation will not work correctly.
>>>>
>>>> (currently both values are wrong, it needs to be fixed, but it's 
>>>> another story)
>>>>
>>>>>> Radxa ROCK Pi E v1.x(DDR3) and ROCK Pi E v3(DDR4) are different
>>>>>> incompatible boards, it must have different "compatible" string.
>>>>>
>>>>> Well, the above-mentioned Nano Pi M4 boards share the same DT and 
>>>>> the same
>>>>> "compatible" value, because for all consumers of the DT, except for 
>>>>> U-Boot
>>>>> that can already handle the differences, they are the same boards.
>>>>
>>>> (un)fortunately Nano Pi M4 boards seems not to be supported by OpenWrt
>>>>
>>>>  https://downloads.openwrt.org/snapshots/targets/rockchip/armv8/
>>>
>>> Thanks for the explanations.  As discussed further in #linux-rockchip
>>> on Libera.Chat, we do need a general solution for this issue, which 
>>> would
>>> get us covered for all the board variants that use different DRAM chips,
>>> which are currently known to U-Boot only.
>>>
>>> I'll keep thinking about this in the next couple of days, and I'll come
>>> back with an update.
>>
>> As a separate thought, is there some way to detect the actual ROCK Pi E
>> board variant at runtime, using some GPIO line, ADC readout, or something
>> similar?  That would help with making it possible to have a single U-Boot
>> build for both board variants.
> 
> as far as I know, no difference. (I asked my colleague)
> I will compare schematics.
> 
> but, if there is difference, is it possible to replace RAM 
> initialization on u-boot?
> 
> btw, RFC:
> 
> https://github.com/RadxaNaoki/u-boot/commit/ff1aa39ffb725d10fbb1608062debe6657f40acc
> 
> -- 
> FUKAUMI Naoki
> Radxa Computer (Shenzhen) Co., Ltd.