On Mon, Nov 09, 2009 at 07:20:26PM -0600, Peter Tyser wrote: > On Tue, 2009-11-10 at 09:08 +0800, Liu Dave-R63238 wrote: > > > On Tue, 2009-11-10 at 08:42 +0800, Liu Dave-R63238 wrote: > > > > > IIRC, 85xx cache is enabled, so when we do the ecc error inject > > > > > test, What will happen before disable ecc error inject? > > > > > I-fetch may get wrong instruction? > > > > > > If you're injecting multibit errors, yes, things could break > > > down, much like a real multibit error. > > > > IIRC, 83xx ECC code will NOT break down when we inject multibit error. > > The code will go on, u-boot also go on... > > What is the benefit of having such a high level of control over error > injection? When do people use this feature? How often do they use it? >
I used the ECC error injection code when adding ECC support on our board, to verify that ECC was actually enabled and reporting errors. I found it extremely useful at the time, though I haven't used it since. > > > > and .... > > > > Because cache is enabled, data bus assume 64 bits (it is > > > normal case). > > > > The DDR bus will have 4-beat burst. So the error > > > information will be > > > > the last beat triggered, or multi-bit error at first beat....., or.. > > > > It is really complex..... > > > > > > I believe all 4 beats would have the ecc error injected. > > > > > > In my opinion, the error reporting functionality of the ECC > > > code is much more important than error injection. Other than > > > testing code during development, when do you inject errors? > > > ECC detection and reporting is useful day-to-day, in the > > > field, during manufacturing tests, etc so that's where the > > > emphasis of this patch is focussed. > > > > 83xx ECC code also has good ECC error reporting functionality, > > IIRC, type ecc status... > > I believe the ecc status command basically just did a register dump of > the ECC registers. In my opinion, the output was overly verbose and not > that useful. The patch I submitted attempts to *decode* the register > dump so Joe User can figure out what's really wrong with their board. > I haven't looked at your code. When I was running the old ecc command, I had the 83xx reference manual open to decode the command's output, IIRC. PS - I'm happy to test stuff on 83xx, I'll try and find time to test this patch series tomorrow. Ira _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
