Hi Simon, I'm very glad you answered this, I was busy with other stuff these last weeks but I had planed to pick this issue again this week.
On 09/28/2014 06:27 AM, Simon Glass wrote: > Hi, > > On 26 August 2014 09:17, Valentin Longchamp > <valentin.longch...@keymile.com> wrote: >> >> Hello, >> >> Here is the outcome of my debug session today: >> >> On 08/25/2014 05:42 PM, Valentin Longchamp wrote: >>> Hello, >>> >>> I am currently porting all the Keymile boards to CONFIG_SYS_GENERIC_BOARD. >>> On u-boot 2014.10-rc1 I have all of them working quite well (at least >>> booting >>> and showing no obvious problem), except for our boards using a MPC8360 >>> from Freescale (kmcoge5ne and kmeter1, both using km8360.h as config) that >>> do >>> not boot at all. >>> >>> I have found out that u-boot crashes as soon as a getenv function call >>> happens >>> before relocation. When I disable them, u-boot seems to work fine. I am >>> currently trying to debug further, but it's not clear yet exactly what >>> causes >>> the crash. >> >> So the problem is that for an unknown reason, the gd->flags are not correct >> and >> getenv actually calls hsearch_h to look for the desired env variable. This >> fails >> before relocation (due to the small stack ?). >> >> If I replace the board_f getenv_ulong calls in board_f.c with my >> getenv_f_ulong >> function that explicitely calls getenv_f the board boots up nicely. >> >> Now the question is, why are my gd->flags not correct/corrupted ? Has someone >> already seen something similar ? I unfortunateley cannot access gd easily >> with >> the BDI, since it is located in the INIT_RAM which is a data cache, for >> which I >> have no LAW configured (could work on that). > > I just saw this. There is condition code at the start of > board_init_f() in board_f.c that might exclude your board. So your > global data might not be zeroed. > That's not exactly the problem here, since defining CONFIG_SYS_GENERIC_GLOBAL_DATA did not solve the problem. However it made me look at the right place and I have noticed that gd->flags are set in the generic board_inif_f() and were not in the previous powerpc specific board_init_f(). If I comment out the gd->flags = boot_flags in the board_init_f() function, then everything works well. Since board_init_f() is called from the assembly code (in my case mpc83xx/start.S), I guess the ulong boot_flags argument ends up being a register (if the arguments are passed in register ... which I am not sure of for powerpc). Since prior to the bl board_init_f call in the start.S file, there is a call another C function (cpu_init_f()), I guess the register passed as argument has an undefined content ... that ends up in gd->flags. I think that the best way to fix this is to make sure from start.S that boot_flags (so the register) has a defined (zeroed ?) content ? But how to make sure which register it is and that this will not change, since the compiler comes into play here ? Valentin _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
