Dear Prabhakar Kushwaha,
In message 4F56DD59.1080304@freescale.com you wrote:
--- a/arch/powerpc/cpu/mpc85xx/start.S +++ b/arch/powerpc/cpu/mpc85xx/start.S @@ -82,6 +82,11 @@ .globl _start_e500
_start_e500: +#if defined(CONFIG_E500_V1_V2) +/* Enable debug exception */
- li r1,MSR_DE
- mtmsr r1
+#endif
Why is this #ifdef needed here?
This #ifdef is to make sure MSR_DE bit is set before u-boot's actual code start executing. it is for overcoming one of the requirement of debugging i.e. Keep MSR_DE bit set.
Sorry, this makes no sense to me. The #ifdef does not change the order of execution, it just enables or disables the code. Are there any situations where omitting this code is required, or where it makes sense?
@@ -729,8 +734,8 @@ create_init_ram_area: msync tlbwe
- lis r6,MSR_IS|MSR_DS@h
- ori r6,r6,MSR_IS|MSR_DS@l
- lis r6,MSR_IS|MSR_DS|MSR_DE@h
- ori r6,r6,MSR_IS|MSR_DS|MSR_DE@l
And why don;t we need such an #ifdef here?
I found similar piece of code in start.S without any #define at label _start_cont. That's why i made it like this. if required i will put it under #define.
Please handle in a consistent way. See above.
Also, CONFIG_E500_V1_V2 is undocumented.
Definition of this #define is part of documentation. I will add comment before using it.
CONFIG_ options must be explained in the README.
Best regards,
Wolfgang Denk