In message 4553B60D.3030901@freescale.com you wrote:
In looking at OF_TBCLK-related code, I noticed that U-Boot has what is basically two structures that contain a variety of "global" data, global_data and bd_info. There are a number of fields in bd_info that also exist in global_data and contain the same value. For instance, we have this in board_init_f():
Right. Historically, we started with bd_info, and gd was added later when we needed to find a way to pass "global data" around in U-Boot. This was mostly a code size optimization - before, we had to pass all this stuff in long argument lists - if any low level function needed such data, we had to pass it though all callers.
From my understanding, the bd_info structure is passed to the kernel as a binary blob, whereas the the global_data structure is used internally by U-Boot to store global data. Obviously, we can't get rid of one or the other.
Correct.
Wouldn't it be better if the bd_info structure were created and initialized only when Linux is about to be booted? Currently, we have some code that uses
Yes, but IIRC also contains information that is noit available in gd, and I don't want to extend gd if it can be avoided, a this is taken from very scarce resources.
bd->xxx and other code that uses gd->xxx, with no real consistence. I think
Actually, in most cases it makes some sense if you think longer about it. But I agree, it's not nice.
the bd_info structure should be local to cmd_bootm.c, and should be allocated and initialized only if we're booting a non-OF version of Linux. This would eliminate using bd-> for anything other than booting non-OF Linux.
Comments?
Did you try to implement this?
Keep in mind that not all the world is a VAX ... oops, wrong decade, a PowerPC. You won't find OFT implementations on ARM, MIPS, NIOS, BF, CF, ...
Best regards,
Wolfgang Denk