12 Nov
2010
12 Nov
'10
10:47 a.m.
On 12/11/10 19:50, Wolfgang Denk wrote:
Dear Reinhard Meyer,
In message 4CDCE769.8080209@emk-elektronik.de you wrote:
Is bootflag ever used? If not, why not change the parameter to give the gd address to board_init_f?
No, bootflag is never used and could / should be removed.
Passing gd as parameter makes no sense, thoug, as it's global data and we reserve a register to store it's address, so it can always be used with minimal overhead.
Which is a really nice idea if you have a register to spare. Unfortunately, x86 does not have this luxury, and the only way I can get gd (and as a consequence upper memory bound for relocation) is to allocate it in assembler and pass to C as a function argument
Regards,
Graeme