Dear Angelo Dureghello, please don't top-post / full quote.
In message <20121113001651.GA21177@angel3> you wrote: > > seems that mcf5307, working at 90Mhz, is not fast enough when "-Os -g" > compile options are set. > > I changed for test config.mk from > > DBGFLAGS= -g # -DDEBUG > OPTFLAGS= -Os #-fomit-frame-pointer > > into > > DBGFLAGS= #-g # -DDEBUG > OPTFLAGS= -O2 #-Os #-fomit-frame-pointer > > common compiles now with -O2 and ymodem works fine again at 115200. Removing -g makes no sense in this cotext. It has no impact on the generated code. I am really surprised about your claim that the -O2 compiled code is actually running faster than the -Os compiled one on a low-end system as yours (90 MHz CPU clock, 8 kB cache size). Which exact tool chain are you using to build the code? > Also, i don't understand why "-g" is set by default. It is set because it is useful to some (those in the need of debugging their code) and does not hurt others. > Is there a way to override/customize this options for this cpu ? I am not convinced that it makes sense to change settings on a per-cpu base. A 90 MHz CPU should be more than sufficient to receive data at 115kbps. I can only compare against 50 MHz PowerQuicc I systems (which is about the lowest end machines I have at hands now), and there no such problem exists. It would be good to understand exactly where the problem is coming from. I don't think that the -Os setting is the core of the problem; I tend to suspect rather your tool chain or your serial driver or such. > Or i have to definitely step down to 57600 ? There should be no need for that. Best regards, Wolfgang Denk -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: w...@denx.de Lispers are among the best grads of the Sweep-It-Under-Someone- Else's-Carpet School of Simulated Simplicity. [Was that sufficiently incendiary? :-)] - Larry Wall in <1992jan10.201804.11...@netlabs.com _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
