Re: [PATCH] ARM: dts: exynos4212-tab3: limit usable memory range

[Krzysztof Kozlowski]

On 21/02/2024 09:26, Krzysztof Kozlowski wrote:
> On 19/02/2024 20:49, Artur Weber wrote:
>> On 19.02.2024 08:44, Krzysztof Kozlowski wrote:
>>> On 17/02/2024 20:02, Artur Weber wrote:
>>>> The stock bootloader on the Samsung Galaxy Tab 3 8.0 provides an
>>>> incorrect available memory range over ATAG_MEM. Limit the usable
>>>> memory in the DTS to prevent it from doing so, without having to
>>>> disable ATAG support.
>>>>
>>>> Signed-off-by: Artur Weber <aweber.kernel@xxxxxxxxx>
>>>> ---
>>>>   arch/arm/boot/dts/samsung/exynos4212-tab3.dtsi | 6 ++++++
>>>>   1 file changed, 6 insertions(+)
>>>>
>>>> diff --git a/arch/arm/boot/dts/samsung/exynos4212-tab3.dtsi b/arch/arm/boot/dts/samsung/exynos4212-tab3.dtsi
>>>> index e5254e32aa8f..9bc05961577d 100644
>>>> --- a/arch/arm/boot/dts/samsung/exynos4212-tab3.dtsi
>>>> +++ b/arch/arm/boot/dts/samsung/exynos4212-tab3.dtsi
>>>> @@ -45,6 +45,12 @@ chosen {
>>>>   		/* Default S-BOOT bootloader loads initramfs here */
>>>>   		linux,initrd-start = <0x42000000>;
>>>>   		linux,initrd-end = <0x42800000>;
>>>> +
>>>> +		/*
>>>> +		 * Stock bootloader provides incorrect memory size in ATAG_MEM;
>>>> +		 * override it here
>>>> +		 */
>>>> +		linux,usable-memory-range = <0x40000000 0x3fc00000>;
>>>
>>> Applied and dropped:
>>>   chosen: linux,usable-memory-range:0: [4611686019496935424] is too short
>>
>> This seems to be a binding issue; the DT schema expects a 64-bit memory 
>> address and size, and doesn't allow a 32-bit range. I've tested the DTS 
>> on my device and this property seems to be handled fine, so I think this 
>> should allow 32-bit values as well.
> 
> Regardless where is the issue: please test before sending.
> 
>>
>> I've opened a PR[1] against devicetree-org/dt-schema (where the schema 
>> for the chosen node is stored) to try and fix this. If my approach is 
>> incorrect, feel free to comment there as well.
> 
> 
> According to Rob's comments, the DTS is the issue.

With updated dtschema I still see the same warning. Is something else
missing?

Best regards,
Krzysztof