Re: [PATCH] ARM: tegra: Correct the length of AHB register space

[Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>]

On 11/12/2013 06:12 PM, Mark Zhang wrote:
> On 11/13/2013 03:05 AM, Stephen Warren wrote:
>> On 11/06/2013 10:32 PM, Mark Zhang wrote:
>>> On Tegra114 it should be 0x12c.
>>
>>> diff --git a/arch/arm/boot/dts/tegra114.dtsi b/arch/arm/boot/dts/tegra114.dtsi
>>
>>>  	ahb: ahb {
>>>  		compatible = "nvidia,tegra114-ahb", "nvidia,tegra30-ahb";
>>> -		reg = <0x6000c004 0x14c>;
>>> +		reg = <0x6000c004 0x12c>;
>>>  	};
>>
>> I don't think this is correct.
>>
>> 0x12c /is/ the address of the last defined register that exists.
>> However, the system memory map table in the TRM indicates that 336 bytes
>> of address space are allocated for this module, so the value should be
>> 0x150 (minus 4 due to the base address offset of 4, so 0x14c) for all of
>> Tegra30/114/124. That matches what's already in DT.
>>
> 
> Yeah, but the 0x12c - 0x14c is not defined in TRM, despite the address
> space in memory map is 336 bytes. So if you add this section into
> register map, that implies writing into this section is OK but this is
> undefined behaviour.

I'm sure there are plenty of undefined register addresses in all the HW
modules in Tegra.