Re: [PATCH v2 4/7] riscv: dts: sophgo: Separate common devices from cv1800b soc

Inochi Amaoto
2023-10-13T22:36:28Z

>
>On Fri, Oct 13, 2023 at 05:52:03PM +0800, Inochi Amaoto wrote:
>> Sorry for the wrong title.
>>
>>> Yo,
>>>
>>> On Mon, Oct 09, 2023 at 07:26:35PM +0800, Inochi Amaoto wrote:
>>>> Move the cpu and the common peripherals of CV181x and CV180x to new file.
>>>>
>>>> Signed-off-by: Inochi Amaoto <inochiama@outlook.com>
>>>> ---
>>>> arch/riscv/boot/dts/sophgo/cv1800b.dtsi | 95 +------------------
>>>> .../dts/sophgo/{cv1800b.dtsi => cv180x.dtsi} | 19 +---
>>>> 2 files changed, 2 insertions(+), 112 deletions(-)
>>>> copy arch/riscv/boot/dts/sophgo/{cv1800b.dtsi => cv180x.dtsi} (80%)
>>>>
>>>> diff --git a/arch/riscv/boot/dts/sophgo/cv1800b.dtsi b/arch/riscv/boot/dts/sophgo/cv1800b.dtsi
>>>> index df40e87ee063..0904154f9829 100644
>>>> --- a/arch/riscv/boot/dts/sophgo/cv1800b.dtsi
>>>> +++ b/arch/riscv/boot/dts/sophgo/cv1800b.dtsi
>>>> @@ -3,106 +3,13 @@
>>>> * Copyright (C) 2023 Jisheng Zhang <jszhang@kernel.org>
>>>> */
>>>>
>>>> -#include <dt-bindings/interrupt-controller/irq.h>
>>>> +#include "cv180x.dtsi"
>>>>
>>>> / {
>>>> compatible = "sophgo,cv1800b";
>>>> - #address-cells = <1>;
>>>> - #size-cells = <1>;
>>>> -
>>>> - cpus: cpus {
>>>> - #address-cells = <1>;
>>>> - #size-cells = <0>;
>>>> - timebase-frequency = <25000000>;
>>>> -
>>>> - cpu0: cpu@0 {
>>>> - compatible = "thead,c906", "riscv";
>>>> - device_type = "cpu";
>>>> - reg = <0>;
>>>> - d-cache-block-size = <64>;
>>>> - d-cache-sets = <512>;
>>>> - d-cache-size = <65536>;
>>>> - i-cache-block-size = <64>;
>>>> - i-cache-sets = <128>;
>>>> - i-cache-size = <32768>;
>>>> - mmu-type = "riscv,sv39";
>>>> - riscv,isa = "rv64imafdc";
>>>> - riscv,isa-base = "rv64i";
>>>> - riscv,isa-extensions = "i", "m", "a", "f", "d", "c", "zicntr", "zicsr",
>>>> - "zifencei", "zihpm";
>>>> -
>>>> - cpu0_intc: interrupt-controller {
>>>> - compatible = "riscv,cpu-intc";
>>>> - interrupt-controller;
>>>> - #address-cells = <0>;
>>>> - #interrupt-cells = <1>;
>>>> - };
>>>> - };
>>>> - };
>>>> -
>>>> - osc: oscillator {
>>>> - compatible = "fixed-clock";
>>>> - clock-output-names = "osc_25m";
>>>> - #clock-cells = <0>;
>>>> - };
>>>>
>>>> soc {
>>>> - compatible = "simple-bus";
>>>> interrupt-parent = <&plic>;
>>>> - #address-cells = <1>;
>>>> - #size-cells = <1>;
>>>> - dma-noncoherent;
>>>> - ranges;
>>>> -
>>>> - uart0: serial@4140000 {
>>>> - compatible = "snps,dw-apb-uart";
>>>> - reg = <0x04140000 0x100>;
>>>> - interrupts = <44 IRQ_TYPE_LEVEL_HIGH>;
>>>> - clocks = <&osc>;
>>>> - reg-shift = <2>;
>>>> - reg-io-width = <4>;
>>>> - status = "disabled";
>>>> - };
>>>> -
>>>> - uart1: serial@4150000 {
>>>> - compatible = "snps,dw-apb-uart";
>>>> - reg = <0x04150000 0x100>;
>>>> - interrupts = <45 IRQ_TYPE_LEVEL_HIGH>;
>>>> - clocks = <&osc>;
>>>> - reg-shift = <2>;
>>>> - reg-io-width = <4>;
>>>> - status = "disabled";
>>>> - };
>>>> -
>>>> - uart2: serial@4160000 {
>>>> - compatible = "snps,dw-apb-uart";
>>>> - reg = <0x04160000 0x100>;
>>>> - interrupts = <46 IRQ_TYPE_LEVEL_HIGH>;
>>>> - clocks = <&osc>;
>>>> - reg-shift = <2>;
>>>> - reg-io-width = <4>;
>>>> - status = "disabled";
>>>> - };
>>>> -
>>>> - uart3: serial@4170000 {
>>>> - compatible = "snps,dw-apb-uart";
>>>> - reg = <0x04170000 0x100>;
>>>> - interrupts = <47 IRQ_TYPE_LEVEL_HIGH>;
>>>> - clocks = <&osc>;
>>>> - reg-shift = <2>;
>>>> - reg-io-width = <4>;
>>>> - status = "disabled";
>>>> - };
>>>> -
>>>> - uart4: serial@41c0000 {
>>>> - compatible = "snps,dw-apb-uart";
>>>> - reg = <0x041c0000 0x100>;
>>>> - interrupts = <48 IRQ_TYPE_LEVEL_HIGH>;
>>>> - clocks = <&osc>;
>>>> - reg-shift = <2>;
>>>> - reg-io-width = <4>;
>>>> - status = "disabled";
>>>> - };
>>>>
>>>> plic: interrupt-controller@70000000 {
>>>> compatible = "sophgo,cv1800b-plic", "thead,c900-plic";
>>>> diff --git a/arch/riscv/boot/dts/sophgo/cv1800b.dtsi b/arch/riscv/boot/dts/sophgo/cv180x.dtsi
>>>> similarity index 80%
>>>> copy from arch/riscv/boot/dts/sophgo/cv1800b.dtsi
>>>> copy to arch/riscv/boot/dts/sophgo/cv180x.dtsi
>>>> index df40e87ee063..ffaf51724c98 100644
>>>
>>> Firstly, this form of diff really threw me, I was quite confused for a
>>> few minutes. A copy plus a pair of diffs doesn't really make much sense,
>>> when the operation being carried is an extraction of some nodes to a
>>> different file.
>>>
>>
>> I was told to use -C/-M/-B to generate patch, and the git format-patch
>> give me this wired output if I use -C, using -M seems no change from v1.
>> The -B output is also disappointing. Maybe I need to generate agaion?
>
>I don't think generating it again is going to change the outcome & I
>don't really think the -C version of this patch makes much sense, it is
>hard to tell what has actually been moved.
>

I mean regenerating without -C, This shows the the code move, but it gives
a huge output, since the git can not detect this move and output all the
moved line in the diff as changed.

>> The v1 version:
>> https://lore.kernel.org/linux-riscv/IA1PR20MB495360B632D106BBB833D82ABBCFA@IA1PR20MB4953.namprd20.prod.outlook.com/
>>
>>>> --- a/arch/riscv/boot/dts/sophgo/cv1800b.dtsi
>>>> +++ b/arch/riscv/boot/dts/sophgo/cv180x.dtsi
>>>> @@ -1,12 +1,12 @@
>>>> // SPDX-License-Identifier: (GPL-2.0 OR MIT)
>>>> /*
>>>> * Copyright (C) 2023 Jisheng Zhang <jszhang@kernel.org>
>>>> + * Copyright (C) 2023 Inochi Amaoto <inochiama@outlook.com>
>>>
>>> Also, is moving around some bits of hw description really a
>>> copyrightable change?
>>>
>>
>> It seems to be a mistake when I splitting the patch from v1.
>> This copyright should in the next patch.
>>
>>>> */
>>>>
>>>> #include <dt-bindings/interrupt-controller/irq.h>
>>>>
>>>> / {
>>>> - compatible = "sophgo,cv1800b";
>>>> #address-cells = <1>;
>>>> #size-cells = <1>;
>>>>
>>>> @@ -48,7 +48,6 @@ osc: oscillator {
>>>>
>>>> soc {
>>>> compatible = "simple-bus";
>>>> - interrupt-parent = <&plic>;
>>>> #address-cells = <1>;
>>>> #size-cells = <1>;
>>>> dma-noncoherent;
>>>> @@ -103,21 +102,5 @@ uart4: serial@41c0000 {
>>>> reg-io-width = <4>;
>>>> status = "disabled";
>>>> };
>>>> -
>>>> - plic: interrupt-controller@70000000 {
>>>> - compatible = "sophgo,cv1800b-plic", "thead,c900-plic";
>>>> - reg = <0x70000000 0x4000000>;
>>>> - interrupts-extended = <&cpu0_intc 11>, <&cpu0_intc 9>;
>>>> - interrupt-controller;
>>>> - #address-cells = <0>;
>>>> - #interrupt-cells = <2>;
>>>> - riscv,ndev = <101>;
>>>> - };
>>>> -
>>>> - clint: timer@74000000 {
>>>> - compatible = "sophgo,cv1800b-clint", "thead,c900-clint";
>>>> - reg = <0x74000000 0x10000>;
>>>> - interrupts-extended = <&cpu0_intc 3>, <&cpu0_intc 7>;
>>>> - };
>>>> };
>>>> };
>>>
>>> What I wanted to comment on was this though - it seems that both the
>>> cv1800b and the cv1812h have identical plic and clint nodes, other than
>>> their compatibles? If that is the case, why create a cv1800b and a
>>> cv1812h specific file containing entirely new nodes, when overriding the
>>> compatible would be sufficient? Doubly so if the other SoCs in the
>>> cv18xx series are going to have identical layouts.
>>>
>>> I gave it a quick test locally with the below diff applied on top of
>>> this series - although I didn't make sure that I didn't re-order the
>>> plic & clint nodes, I just wanted to demonstrate what I had done.
>>>
>>
>> Thanks for demonstration. AFAIK, what you said is true. the most devices
>> of CV180x and CV181x are the same, including plic and clint. The reason I
>> used a new one is to identify these two devices without making the
>> compatible string confusing.
>> Should I change the binding name of plic and clint to "sophgo,cv1800-xxx"
>> to mark there are the same series? I think this can avoid this confusing
>> dt nodes.
>
>I personally don't find the compatibles (or the dt nodes) confusing, so
>I dunno. Having reusing the compatible is not something that I am a fan of
>either, since this seems to be a different soc (given the sram &
>coprocessor etc) even if the addresses of the peripherals are identical.

Thanks. It is more like I have misunderstood something.

>
>