On Thursday 16 June 2011 05:45 PM, Wolfgang Denk wrote:
Dear Aneesh V,
In message4DF9EE03.8010105@ti.com you wrote:
we are also duplicating the structure across different boot media. I think we should re-organize this as follows:
spl/ spl/common/ spl/mmc/ spl/nand/ spl/onenand/
Can you please extend this to show the SoC/board directories etc. I guess they will go under spl/ and not under each media.
Correct, i. e. please add for example:
spl/board/freescale/mx31pdk/ spl/board/freescale/mx31pdk/Makefile ...
I thought we were going to have cpu directory SoC directory etc in this directory structure.
...this changes to: "spl/Makefile, spl/common/Makefile and spl/<bootdevice>/Makefile build libraries with the generic object files at their respective level (assuming these exist).
What's the distinction between spl/Makefile and spl/common/Makefile? I guess we won't have any source files at spl/ level?
I think we can implement the logic to decide which directories need to be entered and built into spl/Makefile, so we can keep this out of the top level Makefile.
spl/common/Makefile is responsible for building the common code in the spl/common/ directory.
Correct, I do not see need for any sources in spl/
We should try to get rid of the need to create symbolic links. If we use the same source files as for the "normal", then we should also use the normal object files.
You mean you will re-use *.o files with normal u-boot? If so, do you want to create symbolic links to them in the SPL directories or use them in-place?
We should use them in-place. Using --gc-sections and -ffunction-sections we have enough granularity to select only what we really need.
Whether you reuse the source code or the object files we still need directories for all the levels for the respective Makefiles, right?
Can we not use the objects that get normally built, with the existing Makefiles?
But where do you add the reference to SoC level and CPU level object files? Which library do you make them part of? I thought the board level Makefile was meant only to build the board specific library.
For example, let's say we have board 'a' and 'b' of same SoC(soc). Unless we have a SoC directory we may have to do something like this.
spl/board/<vendor>/a/Makefile: OBJS := soc_1.o OBJS += soc_2.o OBJS += a.o
spl/board/<vendor>/b/Makefile: OBJS := soc_1.o OBJS += soc_2.o OBJS += b.o
Please note that soc_1.o and soc_2.o are duplicated in the two Makefiles. We are back to square one, right? Or did you have something else in mind?
Also, at least some files will have to be built separately for SPL because they have conditional compilation with CONFIG_PRELOADER kind of flags.
Please let's check where this is needed, and how we can handle this. I'd really like to get rid of this symlinking.
One case is start.S. We need a simplified start.S for SPL(no relocation, no interrupt handling etc).
There are places where CONFIG_PRELOADER is used today. But maybe, these could be avoided it we try.
best regards, Aneesh