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From:   Vineet Gupta <vineet.gupta1@synopsys.com>
To:     Florian Fainelli <f.fainelli@gmail.com>,
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Subject: Re: [PATCH v4 6/6] arch: Move initrd= parsing into
 do_mounts_initrd.c
Thread-Topic: [PATCH v4 6/6] arch: Move initrd= parsing into
 do_mounts_initrd.c
Thread-Index: AQHUdVsG6LD9rqw+mkiEXoDtFpj/vg==
Date:   Tue, 13 Nov 2018 00:57:54 +0000
Message-ID: <C2D7FE5348E1B147BCA15975FBA23075013A592A33@us01wembx1.internal.synopsys.com>
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 <C2D7FE5348E1B147BCA15975FBA23075013A5929ED@us01wembx1.internal.synopsys.com>
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On 11/12/18 4:52 PM, Florian Fainelli wrote:=0A=
> On 11/12/18 4:40 PM, Vineet Gupta wrote:=0A=
>> On 11/12/18 4:38 PM, Florian Fainelli wrote:=0A=
>>>>>  #ifdef CONFIG_BLK_DEV_INITRD=0A=
>>>>> -	if (initrd_start)=0A=
>>>>> -		memblock_reserve(__pa(initrd_start), initrd_end - initrd_start);=
=0A=
>>>>> +	if (phys_initrd_size) {=0A=
>>>>> +		memblock_reserve(phys_initrd_start, phys_initrd_size);=0A=
>>>>> +		initrd_start =3D (unsigned long)__va(phys_initrd_start);=0A=
>>>>> +		initrd_end =3D initrd_start + phys_initrd_size;=0A=
>>>>> +	}=0A=
>>>>>  #endif=0A=
>>>> The common code now uses phys_initrd*, and you also use the same in AR=
C code, do=0A=
>>>> we still need the initrd_* setting here ?=0A=
>>>> ARC semantics was using them as PA anyways.=0A=
>>> Yes, the generic initrd code expects initrd_start/end to be virtual=0A=
>>> addresses, which we now directly derive from phys_initrd_start, that=0A=
>>> should really be equivalent.=0A=
>> So we can skip this explicit setting above - ARC arch code doesn't acces=
s the virt=0A=
>> initrd_start=0A=
> OK, you are saying we could just have the generic initrd code do this=0A=
> assignment instead of having each architecture do it, is that a correct=
=0A=
> understanding? =0A=
=0A=
Correct !=0A=
=0A=
> If so, I suppose it could be done, whether as of this=0A=
> patch series or as a follow-up, either way is fine with me.=0A=
=0A=
If it is not too much trouble, I'd prefer this now. I should have chimed ea=
rlier.=0A=
=0A=
> One possible caveat is if __va() and __phys_to_virt() behave differently=
=0A=
> (e.g: because of CONFIG_DEBUG_VIRTUAL or other things).=0A=
=0A=
=0A=
Thing is, after your patches, we don't use the vanilla initrd_xxx in arch c=
ode any=0A=
longer. So this becomes just an implementation detail, which core code may =
or=0A=
maynot need and if it does, this needs to work already w/o having to set an=
ything=0A=
in arch code. Agree ?=0A=
=0A=
Thx,=0A=
-Vineet=0A=