Abatron Support <supp...@abatron.ch> wrote on 2012/05/31 11:30:57: > > > > Abatron Support <supp...@abatron.ch> wrote on 2012/05/30 14:08:26: > >> > >> >> I have tested this briefly with BDI2000 on P2010(e500) and > >> >> it works for me. I don't know if there are any bad side effects, > >> >> therfore > >> >> this RFC. > >> > >> > We used to have MSR_DE surrounded by CONFIG_something > >> > to ensure it wasn't set under normal operation. IIRC, if MSR_DE > >> > is set, you will have problems with software debuggers that > >> > utilize the the debugging registers in the chip itself. You only want > >> > to force this to be set when using the BDI, not at other times. > >> > >> This MSR_DE is also of interest and used for software debuggers that > >> make use of the debug registers. Only if MSR_DE is set then debug > >> interrupts are generated. If a debug event leads to a debug interrupt > >> handled by a software debugger or if it leads to a debug halt handled > >> by a JTAG tool is selected with DBCR0_EDM / DBCR0_IDM. > >> > >> The "e500 Core Family Reference Manual" chapter "Chapter 8 > >> Debug Support" explains in detail the effect of MSR_DE. > > > So what is the verdict on this? I don't buy into Dan argument without some > > hard data. > > What I tried to mention is that handling the MSR_DE correct is not only > an emulator (JTAG debugger) requirement. Also a software debugger may > depend on a correct handled MSR_DE bit.
Yes, that made sense to me too. How would SW debuggers work if the kernel keeps turning off MSR_DE first chance it gets? Jocke _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev