Le 23/09/2010 18:37, Ben Gardiner a écrit :
On Wed, Sep 22, 2010 at 3:07 PM, Albert ARIBAUDalbert.aribaud@free.fr wrote:
- build with your fix in;
$git log --format=oneline|head -n 3 f619c1537af105cd1471f9447ac9132feab79c3a arm926ejs: reduce code size with -msingle-pic-base 6285f63589a87dfd28c7d73ff68075c5d1ee7f35 arm: change relocation flag from -fPIC to -fPIE e69e520f9d235bb7d96296081fdfc09b9fee8c46 fsl: refactor MPC8610 and MPC5121 DIU code to use existing bitmap and logo features
$git diff diff --git a/arch/arm/cpu/arm926ejs/config.mk b/arch/arm/cpu/arm926ejs/config.mk index aa84706..f8ef90f 100644 --- a/arch/arm/cpu/arm926ejs/config.mk +++ b/arch/arm/cpu/arm926ejs/config.mk @@ -23,11 +23,6 @@
PLATFORM_RELFLAGS += -fno-common -ffixed-r8 -msoft-float
-ifndef CONFIG_SYS_ARM_WITHOUT_RELOC -# needed for optimal relocation -PLATFORM_RELFLAGS += -msingle-pic-base -endif
- PLATFORM_CPPFLAGS += -march=armv5te # ========================================================================= #
$make mrproper; make da850evm_config; make -j9 all [...] make[1]: Entering directory `[...]arch/arm/lib' arm-none-linux-gnueabi-gcc -g -Os -fPIE -fno-common -ffixed-r8 -msoft-float -fno-common -ffixed-r8 -msoft-float -D__KERNEL__ -DTEXT_BASE=0xC1080000 -I[...]/include -fno-builtin -ffreestanding -nostdinc -isystem /opt/codesourcery-arm-none-eabi-2009q1/bin/../lib/gcc/arm-none-linux-gnueabi/4.3.3/include -pipe -DCONFIG_ARM -D__ARM__ -marm -mabi=aapcs-linux -mno-thumb-interwork -march=armv5te -march=armv5te -Wall -Wstrict-prototypes -fno-stack-protector \ -o board.o board.c -c [...]
- debug (at the assembly instruction level) the start.S code and see what
value ends up in r10 (aka sl) right before calling board_init_f;
(gdb) p /x $r10 $1 = 0xc1098564 (gdb) p /x $pc $2 = 0xc1080088
- proceed (still at the assembly instruction level) until you get within
board_init_f. Among the first instructions will be the recomputation of 10/sl; see what value it is assigned;
(gdb) p /x $r10 $5 = 0xc1098564 (gdb) p /x $pc $6 = 0xc1080694 (gdb)
- compare values found in 2 and 3 with the value of __got_base in the .map
file.
$cat System.map |grep __got_base c1098564 A __got_base
I hope that helps.
Well, it confirms that the start.S code computes a correct r10 / sl register, since it is the same value as board_init_f (and any other function) computes when -msingle-pic-base is not present, and this value is that of __got_base.
Note that if I'm not mistaken, your build uses r9 as the pic base, not 10 -- this is a possibility, and my patches are written so as to allow either register use.
Now, we need to find out why board_init_f fails to go through the init sequence and print out at least the banner and some diagnostics.
Please build with my two patches alone (i.e., put -msingle-pic-base back in place, which will remove the recomputation of the pic base in every function), and run it until board_init_f() calls its first init function through (*init_fnc_ptr)(). This call should be materialized by a 'blx <reg>' instruction; please report the value of <reg> at that point as well as the addresses of arch_cpu_init, board_early_init_f, and timer_init; <reg> should be one of these depending on the board config.
Best Regards, Ben Gardiner
Thanks again for your help in testing my patches!
Amicalement,