[PATCH v5 1/2] arm: rmobile: Add RZ/G2[HMNE] SoC support

[Biju Das]

Hi Marek,

> Subject: Re: [PATCH v5 1/2] arm: rmobile: Add RZ/G2[HMNE] SoC support
> 
> On 11/1/20 8:26 PM, Biju Das wrote:
> > Hi Marek,
> 
> Hi,
> 
> [...]
> 
> >>> @@ -23,7 +48,9 @@ static u32 rmobile_get_prr(void)
> >>>
> >>>   u32 rmobile_get_cpu_type(void)
> >>>   {
> >>> -	return (rmobile_get_prr() & 0x00007F00) >> 8;
> >>> +	const u32 soc_id = (rmobile_get_prr() & 0x00007F00) >> 8;
> >>
> >> The soc_id = ... can be inlined into get_cpu_type().
> >>
> >> However, you might want to cache the result of rmobile_get_cpu_type()
> >> , because doing OF match every time this is called is expensive.
> >
> > I agree calling OF match is expensive. So I have ported Renesas SoC
> > identification driver  from Linux to u-boot which will cache the
> > family type, soc_id and revision. I already sent a patch for
> > supporting soc_id in UCLASS_SOC in ML[4] [4]
> >
> https://jpn01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fpatch
> > work.ozlabs.org%2Fproject%2Fuboot%2Fpatch%2F20201030140724.12773-
> 1-bij
> >
> u.das.jz%40bp.renesas.com%2F&data=04%7C01%7Cbiju.das.jz%40bp.r
> enes
> >
> as.com%7C23804e7d89d0437047b308d87f654edd%7C53d82571da1947e49cb4
> 625a16
> >
> 6a4a2a%7C0%7C1%7C637399420383910105%7CUnknown%7CTWFpbGZsb3d8
> eyJWIjoiMC
> >
> 4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&
> amp;sd
> >
> ata=%2Bu6HZyimz2%2Froy%2FEfTAzAxXupL0hDSBGUqT4%2B%2F2lVJ8%3D&
> amp;reser
> > ved=0
> >
> > On the next version, I will send Renesas SoC identification driver,
> > which supports caching family type which can be used to provide unique
> identification for CPU type.
> 
> Please make sure to check it on RCar2 as well, those use SPL and the SPL size
> is quite limited.

Currently SoC identification driver is enabled only for RZ/G2 boards and support is added to both R-Car Gen3 and RZ/G2 devices.

For the disabled case, the UCLASS-SOC class functions are inlined to "NULL"  for soc_device_match and rest of the api's it is "-ENOSYS".

I agree, in future we need to add support for RCar2 as well, since we are going to add u-boot support for RZ/G1 devices.
Please find the size details related to R-Car Gen2(by adding support for R-Car M2-W and RZ/G1M SoC).

There is increase of 944 bytes, for R-Car Gen2 device, if we enable Renesas SoC identification driver for Gen2 devices.

Current u-boot-sh/master
-----------------------------------
$ ls -al u-boot.bin 
-rw-r--r-- 1 biju biju 523001 Nov  3 09:16 u-boot.bin

Current u-boot-sh/master + SoC renesas driver (R-Car M2-W enabled only case)
--------------------------------------------------------------------------------------------
$ ls -al u-boot.bin 
-rw-r--r-- 1 biju biju 523945 Nov  3 09:47 u-boot.bin

If you agree, we will add support for Gen2 to SoC identification driver later. Currently there is no users for using it.
Please let me know.

Regards,
Biju