hi~
thanks for your reply. sorry for my ability of writing and understanding the code =D
btw, How contribute my idea of this function, I means, it should be more clean or easy just like this:
unsigned long get_ram_size(volatile long *base, long maxsize) {
unsigned long mem; for (mem = (*base); mem < (maxsize); mem <<= 1)) { if (*(unsigned long *)((unsigned long)(get_ram_size) + mem) == *(unsigned long *)(get_ram_size)) break; } }
On Thu, Jun 25, 2009 at 8:56 PM, Detlev Zundel dzu@denx.de wrote:
Hi ya,
I could not understand common/memsize.c, how it works?
Like a charm ;)
maxsize / sizeof (long), what's meaning of it? why sizeof (long) is dividend?
As the comment in line 50 states, "cnt" is used in pointer arithmetic, so addr is increased in sizeof(long) bytes. maxsize however is considered to be in bytes only. Makes sense?
just like stack, push every step mem addr to save:
save[i++] = *addr; and then?
Cannot parse the question.
The algorithm should be pretty clear however (take a paper and pencil and work out the values of addr as it proceeds) - we save the original content of the adressed cells and write our own pattern there (~cnt). Then we walk these cells upward and see where the previous write did not work like it was supposed to - voila.
Cheers Detlev
-- The continental people think life is a game. The English think cricket is a game. -- George Mikes -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-40 Fax: (+49)-8142-66989-80 Email: dzu@denx.de