diff options
Diffstat (limited to 'c/src/lib/libbsp/powerpc/motorola_powerpc/BOOTING')
| -rw-r--r-- | c/src/lib/libbsp/powerpc/motorola_powerpc/BOOTING | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/powerpc/motorola_powerpc/BOOTING b/c/src/lib/libbsp/powerpc/motorola_powerpc/BOOTING index 5565fbb2b3..a8e58c3f27 100644 --- a/c/src/lib/libbsp/powerpc/motorola_powerpc/BOOTING +++ b/c/src/lib/libbsp/powerpc/motorola_powerpc/BOOTING @@ -6,6 +6,24 @@ This file documents the on board monitor (PPCBUG) configuration used to be able to boot the archives located in powerpc-rtems/c/mcp750/bin. This information was provided by Eric Valette <valette@crf.canon.fr> +NOTE (by Till Straumann <strauman@slac.stanford.edu>, 2003): +Apparently, PPCBug fails to shut down the network interface after +loading an image. This means that the ethernet chip is still able +to write into its descriptors and network buffer memory which +can result in the loaded system to be corrupted if that system +relocates itself!. The proper place to shut down the interface +would be PPCBug itself or a 'PPCBug startup script' - unfortunately, +PPCBug doesn't offer such a feature. Therefore, the bootloader +is by default compiled with the +#ifdef USE_PPCBUG +compile-time option ENABLED. It will then use a PPCBug system +call to shut down the ethernet chip during an early stage of +the boot process. +NOTE: THIS (i.e. the system call) WILL FAIL IF YOU USE SOFTWARE +OTHER THAN PPCBUG TO BOOT THE BSP. In such a case, you must +recompile with #undef USE_PPCBUG and make sure the ethernet +interface is quiet by other means. + ----------------------- ENV command-------------- PPC1-Bug>env Bug or System environment [B/S] = B? |