Hi Wolfgang, On 30/08/11 19:29, Wolfgang Denk wrote: > Dear Graeme Russ, > > In message > <CALButC+t=oul9xgqnfyadzmgpjrp7mdrwee9lkogyheg1d+...@mail.gmail.com> you > wrote: >> >>> If you want to support arbitrary buffer sizes, then just use >>> >>> #define CIRC_BUF_IDX(idx) ((idx) % CONFIG_SYS_TMP_CON_BUF_SZ) >> >> I know, but I was concerned that you wouldn't like the use of modulo >> arithmetic for every putc() - But I suppose thats cheaper than a compare >> plus branch... > > Well, the difference of "i & (CONFIG_SYS_TMP_CON_BUF_SZ-1)" versus > "i % CONFIG_SYS_TMP_CON_BUF_SZ" is 1 versus 4 assembler instructions > on Power, and 2 versus 5 assembler instructions on ARM. I think we > can tolerate this.
And it's only hit during printf() before console is initialised :) Respinning now Regards, Graeme _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
