Re: [PATCH 2/2] ARM: Allow either FLATMEM or SPARSEMEM on the multiplatform build

[Florian Fainelli <f.fainelli@gmail.com>]

On 5/7/2020 1:11 PM, Florian Fainelli wrote:
> 
> 
> On 5/7/2020 12:27 AM, Mike Rapoport wrote:
>> On Wed, May 06, 2020 at 04:50:09PM -0700, Florian Fainelli wrote:
>>> From: Gregory Fong <gregory.0xf0@gmail.com>
>>>
>>> ARMv7 chips with LPAE can often benefit from SPARSEMEM, as portions of
>>> system memory can be located deep in the 36-bit address space.  Allow
>>> FLATMEM or SPARSEMEM to be selectable at compile time; FLATMEM remains
>>> the default.
>>>
>>> This is based on Kevin's "[PATCH 3/3] ARM: Allow either FLATMEM or
>>> SPARSEMEM on the multi-v7 build" from [1] and shamelessly rips off his
>>> commit message text above.  As Arnd pointed out at [2] there doesn't
>>> seem to be any reason to tie this specifically to ARMv7, so this has
>>> been changed to apply to all multiplatform kernels.
>>>
>>> [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-September/286837.html
>>> [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-October/298950.html
>>>
>>> Cc: Kevin Cernekee <cernekee@gmail.com>
>>> Tested-by: Stephen Boyd <sboyd@codeaurora.org>
>>> Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
>>> Signed-off-by: Doug Berger <opendmb@gmail.com>
>>> Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
>>> ---
>>>  arch/arm/Kconfig | 5 +++++
>>>  1 file changed, 5 insertions(+)
>>>
>>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
>>> index 5986277296c3..7bb5264a9c3a 100644
>>> --- a/arch/arm/Kconfig
>>> +++ b/arch/arm/Kconfig
>>> @@ -312,6 +312,8 @@ choice
>>>  config ARCH_MULTIPLATFORM
>>>  	bool "Allow multiple platforms to be selected"
>>>  	depends on MMU
>>> +	select ARCH_FLATMEM_ENABLE
>>> +	select ARCH_SPARSEMEM_ENABLE
>>
>> The logic in mm/Kconfig is quite convoluted, so selecting
>> ARCH_SPARSEMEM_ENABLE will automatically make SPARSEMEM the only option.
>>
>> On top of this you would need to enable ARCH_SELECT_MEMORY_MODEL, e.g.
>> something like:
> 
> Yes indeed, thanks that does allow me to select between flatmem and
> sparsemem from menuconfig correctly now.

Mike, do you want to make a formal submission to Russell's patch
tracker? If so, feel free to add:

Tested-by: Florian Fainelli <f.fainelli@gmail.com>

Thanks!
--
Florian

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel