hi,

apologies for asking a stupid question, tell me how are you guys are testing
anything that you are developing. either any changes any linux kernel or
something new. Is it some simulator or a VM or directly into some hardware.
whats the best practice. any links related to this will be very helpful

thanks

--Vinit

On Mon, Oct 4, 2010 at 11:58 AM, arshad hussain <[email protected]>wrote:

> On 10/2/2010 3:08 AM, Sri Ram Vemulpali wrote:
>
>> Hi All,
>>
>>       I am developing segmentation for my kernel. In that process I
>> choose to divide whole memory in to fixed size segments. So a 4GB
>> memory can be divided in to 8192 segments. So I initialize segment
>> descriptors in to the GTD withs segments base address and limit. Here
>> base address are 0,0x10000,0x20000,..... and limit is 64kb always for
>> every segment. For a task if I choose a segment to assign, I will
>> place the index of that segment descriptor in to CS, DS. Now when
>> process generates address to put on address bus, then it will do
>> computation from logical address to linear address.
>> After processor picks logical address, it chooses segment descriptor
>> and adds this 32-bit logical address to segment base address to
>> generate linear address. Now my question is, if my segment size is
>> 64kb, how is that 32-bit offset is added to segment base address,
>> which is not right.
>>
>
> As you know the limit is the _max_ which a single segment can scale.
> IE 32bit or 4GB. Since segments need not have a fix size
>
>
> It should only consider 16-bit offset to add to
>
> there is a granularity bit which determines the 16bit (1MB)
> vs the 32bit.
>
>
>  base to generate linear address. How can I tell to my processor to
>> choose only 16-bit offset.
>>
>
> the granularity bit if cleared (zero) determines a 16bit address.
>
>
> Does processor drives offset bit width
>
>> automatically based on limit defined in segment descriptor.
>>
>> Any insight in to this will help me. please clarify my doubt. Waiting
>> for you reply.
>>
>> Regards,
>> Sri.
>>
>>
> Thanks
>
>
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