Re: [PATCH v5 5/6] arm64: dts: qcom: Add support for QCS9075 Ride & Ride-r3

[Wasim Nazir]

On Mon, Mar 03, 2025 at 08:46:55AM +0100, Krzysztof Kozlowski wrote:
> On 27/02/2025 08:37, Wasim Nazir wrote:
> > On Wed, Jan 15, 2025 at 09:35:34AM +0100, Krzysztof Kozlowski wrote:
> >> On 15/01/2025 06:48, Wasim Nazir wrote:
> >>>> The the SoC, I am asking about the board. Why each of them is for
> >>>> example r3?
> >>>>
> >>>> So this is not sufficient explanation, nothing about the board, and
> >>>> again just look Renesas and NXP.
> >>>>
> >>>
> >>> Hi Krzysztof,
> >>>
> >>> sa8775p(AUTO), qcs9100(IOT), qcs9075(IOT) are different SoCs based on
> >>> safety capabilities and memory map, serving different purpose.
> >>> Ride & Ride-r3 are different boards based on ethernet capabilities and
> >>> are compatible with all the SoCs mentioned.
> >>
> > 
> > Hi Krzysztof,
> > 
> >> Compatible? What does it mean for a board?
> >>
> > 
> > Ride board is based on multiple daughter cards (SOC-card, display,
> > camera, ethernet, pcie, sensor, etc.).
> > 
> > The SOC is not directly soldered to Ride board, instead SOC is soldered
> > on SIP (System in Package) card which can be mounted on SOC-daughter card of
> > Ride board.
> > 	- SoC => SIP-card => SOC-daughter-card (Ride)
> 
> 
> So basically pretty like other designs using SoM.
> 
> > 
> > Together with SIP cards and other daughter cards we are creating different
> > <soc>-Ride Variants with differences in memory map & thermal mitigations.
> > 
> > The SIP card consists of SOC, PMIC & DDR and it is pin compatible to the
> > SOC daughter card of <soc>-Ride board. Only SOC is changing accross SIP
> > cards, except an additional third party SIL-PMIC for SAIL, which is not
> > present in QCS9075 Ride.
> 
> Just like every SoM
> 
> > 
> > Other daughter cards remains same for <soc>-Ride variants, except
> > ethernet card which is different for <soc>-Ride rev3 variants.
> > 
> > So the Ride board (combination of daughter cards) is same across the SIP,
> > while SOC on SIP card is changing which can be sa8775p, qcs9100 or qcs9075.
> > 
> >> Third time: did you look how other vendors do it?
> >>
> > 
> > Yes, we have reviewed other vendors. However, please feel free to share
> > any specific reference you would like us to follow.
> > 
> > Here are few reference files we found from other vendors where similar
> > tasks are performed which includes code refactoring and HW modularity:
> >  - Freescale: fsl-ls208xa.dtsi, fsl-ls2088a.dtsi, fsl-ls2081a-rdb.dts
> 
> That's an unexpected choice - I would rather look at dozen of SoMs for
> iMX platforms.
> 
> >  - Renesas: white-hawk-common.dtsi, r8a779g0-white-hawk.dts
> >  - Rockchip: px30-engicam-common.dtsi, px30-engicam-ctouch2.dtsi,
> >    px30-engicam-px30-core-ctouch2.dts
> > 
> > In our case along with describing the HW, code refactoring is also done
> > which might be causing confusion, but we are ready for any inputs for
> > correction.
> 
> I don't understand why this was not properly described since beginning.
> You had the hardware in your hands and went with incomplete or even
> incorrect hardware description.
> 
> > 
> > Putting this pictorial diagram for updated DT structure depicting our HW.
> >  - qcs9xxx-module.dtsi specifying QCS9xxx based SIP card/module having
> >    SoC, PMICs, Memory-map updates.
> >  - qcom-ride-common.dtsi specifying ride daughter boards, here we are
> >    doing code refactoring also as this is common for all ride boards.
> >  - qcom-ride-ethernet-aqr115c.dtso specifying ethernet overlay board which
> >    uses 2.5G phy and can be overlayed to ride boards to get ride-r3.
> >    By default ride uses 1G phy.
> >  - qcs9075-iq-9075-evk.dts is the new name for RB8 as per new product
> >    name. We will be changing this in next patch series.
> > 
> > +-----------------------------------------------------------------------------------------------------------------------------------------------+
> > |                                                                                                                                               |
> > |                                                          sa8775p.dtsi                                                                         |
> > |                                                              |                                                                                |
> > |                                    +-------------------------+-----------------------+                                                        |
> > |                                    |                         |                       |                                                        |
> > |                                    v                         |                       v                                                        |
> > |                             qcs9075-module.dtsi              |                qcs9100-module.dtsi                                             |
> 
> So this is the SoM?

Yes this is SoM.

> 
> > |                                    |                         |                       |                                                        |
> > |                                    v                         v                       v                                                        |
> > |                                  (IOT)                    (AUTO)                   (IOT)                                                      |
> > |                                    |                         |                       |                                                        |
> > |             +----------------------+                         |                       |                                                        |
> > |             |                      |                         |                       |                                                        |
> > |             |                      | +-------------------------+-----------------------+-------------------< qcom-ride-common.dtsi            |
> 
> Which piece of actual hardware is represented in qcom-ride-common?
> 

All daughter cards like SOC-card, display, camera, ethernet, pcie, sensor, etc.

> > |             |                      | |                       | |                     | |                                                      |
> > |             v                      v v                       v v                     v v                                                      |
> > |  qcs9075-iq-9075-evk.dts     qcs9075-ride.dts         sa8775p-ride.dts         qcs9100-ride.dts                                               |
> > |                                    |                         |                       |                                                        |
> > |                                    | +-------------------------+-----------------------+-------------------< qcom-ride-ethernet-aqr115c.dtso  |
> > |                                    | |                       | |                     | |                                                      |
> > |                                    v v                       v v                     v v                                                      |
> > |                             qcs9075-ride-r3.dts      sa8775p-ride-r3.dts      qcs9100-ride-r3.dts                                             |
> 
> I think I gave already few times that answer: No. You cannot reference
> from a module.c another .c file. You cannot reference DTS from DTS.
> 
> Strictly speaking you can, of course, but you must not. That's not how
> source code is done to be manageable and readable.

Ah the arrow is leading to confusion.

Actually we are not including dts here instead *.dtso file will be
overlayed to *-ride.dts to generate *-ride-r3.dts.

Below is the correct arrow sequence.

|  qcs9075-iq-9075-evk.dts     qcs9075-ride.dts         sa8775p-ride.dts         qcs9100-ride.dts                                               |
|                                    |                         |                       |                                                        |
|                                    +-------------------------+-----------------------+---------------------< qcom-ride-ethernet-aqr115c.dtso  |
|                                    |                         |                       |                                                        |
|                                    v                         v                       v                                                        |
|                             qcs9075-ride-r3.dts      sa8775p-ride-r3.dts      qcs9100-ride-r3.dts                                             |

> 
> > |                                                                                                                                               |
> > +-----------------------------------------------------------------------------------------------------------------------------------------------+
> > 
> >>>
> >>> With the combination of these 3 SoCs and 2 boards, we have 6 platforms,
> >>> all of which we need.
> >>> - sa8775p-ride.dts is auto grade Ride platform with safety feature.
> >>> - qcs9100-ride.dts is IOT grade Ride platform with safety feature.
> >>> - qcs9075-ride.dts is IOT grade Ride platform without safety feature.
> >>>
> >>> Since the Ride-r3 boards are essentially Ride boards with Ethernet
> >>> modifications, we can convert the Ride-r3 DTS to overlays.
> >> How one board can be with multiple SoCs? If it is soldered, it's close
> >> to impossible - that's just not the same board. If it is not soldered,
> >> why you are not explaining it? What is Ride board? What is there? What
> >> can go there? How it can be used in other SoCs? Or for which SoCs? Is
> >> there a datasheet available?
> >>
> > 
> > As our SoC is based on SIP card and SIP card is compatible with Ride
> > board, we could able to use same Ride board (which is combination of
> > multiple daughter cards) with multiple SIP cards.
> > These SIP cards can be of sa8775p, qcs9100 or qcs9075 SOC.
> 
> Describe properly the hardware - if you have a module or SIP if you
> decide not to use industry-standard naming (but why...), then describe
> it in DTSI.

We refer to it as ‘module’ in our datasheet, so I use the same term
here. Thanks for pointing it out; we can proceed with the SoM name.

Below is the updated diagram:
+-----------------------------------------------------------------------------------------------------------------------------------------------+
|                                                                                                                                               |
|                                                          sa8775p.dtsi                                                                         |
|                                                              |                                                                                |
|                                    +-------------------------+-----------------------+                                                        |
|                                    |                         |                       |                                                        |
|                                    v                         |                       v                                                        |
|                             qcs9075-som.dtsi                 |                qcs9100-som.dtsi                                                |
|                                    |                         |                       |                                                        |
|                                    v                         v                       v                                                        |
|                                  (IOT)                    (AUTO)                   (IOT)                                                      |
|                                    |                         |                       |                                                        |
|             +----------------------+                         |                       |                                                        |
|             |                      |                         |                       |                                                        |
|             |                      | +-------------------------+-----------------------+-------------------< qcom-ride-common.dtsi            |
|             |                      | |                       | |                     | |                                                      |
|             v                      v v                       v v                     v v                                                      |
|  qcs9075-iq-9075-evk.dts     qcs9075-ride.dts         sa8775p-ride.dts         qcs9100-ride.dts                                               |
|                                    |                         |                       |                                                        |
|                                    +-------------------------+-----------------------+---------------------< qcom-ride-ethernet-aqr115c.dtso  |
|                                    |                         |                       |                                                        |
|                                    v                         v                       v                                                        |
|                             qcs9075-ride-r3.dts      sa8775p-ride-r3.dts      qcs9100-ride-r3.dts                                             |
|                                                                                                                                               |
+-----------------------------------------------------------------------------------------------------------------------------------------------+

> 
> Best regards,
> Krzysztof

Thanks & regards,
Wasim