Re: [U-Boot] [PATCH 1/3] [RFC] Add support for early serial debugconsole
> It's weekend, and not many people are active now. Let's wait for a > few more days if anybody shows up with arguments to support your > patches. In my opinion, the serial device should be the first device initialized and utilized before all other devices where that is possible. For example, it would be very useful to have serial output while debugging RAM initialization. An early serial port prior to U-Boot relocating itself would be very useful for porting U-Boot to new boards. An early debug serial port would be a good candidate for mainline U-Boot: CONFIG_DEBUG_EARLY_SERIAL has been implemented in a few forks of U-Boot. I also favor an early serial debug console as advocated by this patch, but perhaps its code should be self contained. I'm not sure it is a good idea to modify some commands so they can be run before RAM relocation. If such a thing can be done simply, it should be done for all commands. Is the patch submitted clean enough? No, the implementation could be improved with some effort; a few #if - #else - #endif clauses could be eliminated for example. Would an easier to maintain implementation even be feasible? I agree that a JTAG debugger is extremely useful for board bring-up, but they are very expensive. I'm strongly in favor of having some early serial functionality whether in the form of simply being able to send output to the serial port or having a semi-functional to fully functional shell prior to RAM relocation. Sincerely, Ken Fuchs ___ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
Re: [U-Boot] [PATCH 1/3] [RFC] Add support for early serial debugconsole
[EMAIL PROTECTED] wrote: > I'm strongly in favor of having some early serial functionality > whether in the form of simply being able to send output to the > serial port or having a semi-functional to fully functional shell > prior to RAM relocation. We already have the former. -Scott ___ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
Re: [U-Boot] [PATCH 1/3] [RFC] Add support for early serial debugconsole
Dear [EMAIL PROTECTED], In message <[EMAIL PROTECTED]> you wrote: > > In my opinion, the serial device should be the first device > initialized and utilized before all other devices where that > is possible. For example, it would be very useful to have This is exactly how U-Boot was designed. However, we try to do this in C, and we try to support all kinds of hardware to do so. > serial output while debugging RAM initialization. An early > serial port prior to U-Boot relocating itself would be very > useful for porting U-Boot to new boards. We have that, and always had this as long U-Boot and PPCBoot exist. > Is the patch submitted clean enough? No, the implementation The patch itself may be ok, but the concept is broken, and that's why I reject it. > I agree that a JTAG debugger is extremely useful for board > bring-up, but they are very expensive. Calculate you own time wasted on fruitless attempts to get a board working times your hourly rate and you get ... enough money for more than one BDI3000. > I'm strongly in favor of having some early serial functionality > whether in the form of simply being able to send output to the > serial port or having a semi-functional to fully functional shell > prior to RAM relocation. But hey, we *do* have this. We just don't have an interactve shell prompt. 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: [EMAIL PROTECTED] That Microsoft, the Trabant of the operating system world, may be glancing over the Berlin Wall at the Audis and BMWs and Mercedes. In their own universe Trabants and Ladas were mainstream too... -- Evan Leibovitch ___ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot