[PATCH v15 08/12] ARM: config: append lpae configuration

[Olof Johansson]

On Wed, Jul 30, 2014 at 7:24 PM, Haojian Zhuang
<haojian.zhuang at linaro.org> wrote:
> On 31 July 2014 09:01, Olof Johansson <olof at lixom.net> wrote:
>> On Tue, Jul 29, 2014 at 3:43 AM, Haojian Zhuang
>> <haojian.zhuang at linaro.org> wrote:
>>> On 29 July 2014 12:05, Olof Johansson <olof at lixom.net> wrote:
>>>> On Mon, Jul 28, 2014 at 09:57:52PM +0800, Haojian Zhuang wrote:
>>>>> Append multi_v7_lpae_config. In this default configuration,
>>>>> CONFIG_ARCH_MULTI_V6 is disabled. CONFIG_ARM_LPAE is enabled.
>>>>
>>>> NACK. This is the nth time I have had to nack this patch.
>>>>
>>>> You are enabling platforms here that don't have LPAE. Don't do that.
>>>>
>>>> It's trivial to create a LPAE version of multi_v7 defconfig locally.
>>>>
>>>>
>>>> -Olof
>>>
>>> I tried to remove those SoCs that can't support LPAE. But I don't know
>>> every platform in details.
>>>
>>> How about that I only enable HIP04 in multi_v7_lpae_defconfig. If you
>>> think any platform could be added, please help to list it. Then I
>>> could append them into the multi_v7_lpae_defconfig.
>>
>> I really don't like having to repeat this over and over: Just add LPAE
>> to a multi_v7_defconfig build when you need to turn it on.
>>
>> The alternative is to do this right from the beginning, and move
>> multi_v7 over to be a v6_v7 defconfig, and also have an lpae+kvm
>> defconfig for A7/12/15/17 (and mvebu/krait) platforms. But there's
>> been no need for that yet since all platforms to date can boot without
>> LPAE just fine -- in fact most of them don't actually need it since
>> nearly all of them have less memory and for the few of them that do
>> you just turn on LPAE manually like I suggested.
>>
>>
>> -Olof
>
> I can drop both hip04_defconfig & multi_v7_lpae_defconfig. But the
> problem is that 16GB memory is used in hip04 platform. 64bit memory
> address is also used in hip04 dts file. So I can't boot kernel without
> LPAE configuration.
>
> If I integrate ARCH_HIP04 & LPAE into hi3xxx_defconfig, both
> ARCH_HI3XXX & ARCH_X5HD2 don't support LPAE.

There is memory at 0x10000000-0xd0000000 and all I/O is below 4GB. You
should be able to boot just fine without LPAE, but you won't see all
memory available.


-Olof