Re: [PATCH] setup.c: introduce __pa_symbol() and get ride of CPHYSADDR()

[Franck Bui-Huu <vagabon.xyz@gmail.com>]

Atsushi Nemoto wrote:
> On Tue, 10 Oct 2006 15:49:27 +0200, Franck Bui-Huu <vagabon.xyz@gmail.com> wrote:
>> heh ? I'm wondering if anybody is using 'CONFIG_BUILD_ELF64=n' config at
>> all...
> 
> arch/mips/configs/bigsur_defconfig:# CONFIG_BUILD_ELF64 is not set
> arch/mips/configs/ip27_defconfig:# CONFIG_BUILD_ELF64 is not set
> arch/mips/configs/ip32_defconfig:# CONFIG_BUILD_ELF64 is not set
> arch/mips/configs/ocelot_c_defconfig:# CONFIG_BUILD_ELF64 is not set
> arch/mips/configs/ocelot_g_defconfig:# CONFIG_BUILD_ELF64 is not set
> arch/mips/configs/sb1250-swarm_defconfig:# CONFIG_BUILD_ELF64 is not set
> 
> According to arch/mips/configs, nobody is using CONFIG_BUILD_ELF64=y :-)
> 
> Also one might use gcc 3.x which ignore -msym32 option ...
> 

yeah, that's probably the reason...

>> Atsushi, do you have any idea on how address are translated with
>> 'CONFIG_BUILD_ELF64=n' config ? How such code is supposed to work ?
>>
>> 	code_resource.start = virt_to_phys(&_text);
>>  	code_resource.end = virt_to_phys(&_etext) - 1;
>> 	data_resource.start = virt_to_phys(&_etext);
>>  	data_resource.end = virt_to_phys(&_edata) - 1;
>>
>> Let's say that '&_text' is in KSEG0 and is equal to 0xffffffff80000000.
>> In this case virt_to_phys() returns 0x57ffffff80000000
>> (with PAGE_OFFSET = 0xa800000000000000). Is this physical address
>> correct ?
> 
> I think this peice of code is just broken, as you said.  This is bogus
> but harmless since we have not checked these resources are
> successfully registered or not.
> 

what about all other uses of virt_to_phys(x) ? And what the point to set
PAGE_OFFSET to 0xa800000000000000 ? I'm really confused...

		Franck