[PATCH dtc] Implement the -R option and add a -S option.
Jerry Van Baren
gvb.uboot at gmail.com
Sat Apr 14 22:58:49 EST 2007
David Gibson wrote:
> On Thu, Apr 05, 2007 at 01:10:40PM -0400, Jerry Van Baren wrote:
>> Scott Wood wrote:
>>> On Wed, Apr 04, 2007 at 10:04:33PM -0400, Jerry Van Baren wrote:
>>>> Implement the -R <number> option to add memory reserve slots.
>>>> Add a -S <size> option makes the blob at least this number of bytes.
>>> Wouldn't it be better to just specify the amount of extra space, instead
>>> of the minimum total space? That way, you only need to know what you
>>> intend to add, not how much is already there.
>> I thought briefly about this, but decided to implement a fixed size so
>> that someone could allocate, say, 8K of memory in their memory map
>> (likely flash) and know their blob would fit.
>> Maybe we need a little -s option to say "add -s bytes".
> I think having both options would be a good idea. It would also be
> nice to have options to do this from the dts file (something similar
> to /memreserve/).
>> Jon suggested a --stats option to print out the important statistics.
>> That would also be a good enhancement.
> Ok. How would you envisage this working?
> I've thought for some time that it would be a good idea to add an
> "info" output mode. In that mode instead of outputting a converted
> device tree, it would give various bits of info on the input tree.
> This would include things like the header field debugging information
> that's currently output as pseudo-error messages when using dtb input.
> I'm not sure to what extent your "--stats" idea would overlap with
Well, that was Jon's suggestion/idea so I have not thought about it
much. It would probably overlap 100% with your --info idea, with the
exception that Jon's suggestion would also put out the blob.
Since the dtc puts out the blob to sdtout, this actually is problematic.
I presume that is why you suggest inhibiting output. Using stderr
would sorta bypass that problem, but is not ideal (IMHO).
Is there any reason we don't have a -o option to direct the compiled
blob output to a file? Since the usual use is to write to a file, it
would free up stdout for (info/stats) outputs.
On an unrelated related note, I don't believe my -R additions are
actually putting out additional reserve map slots (easiest to see using
the asm format output). I'm still trying to understand why not, it
seemed pretty straight-forward. When I implemented it, I was looking at
hexdumps of the dtb binary format and looking at the header and thought
I had it working... using it with my u-boot mods shows no extra reserved
slots. I'm looking into where I went wrong.
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