Hi Wolfgang,
Sorry for delayed response.
On Wednesday 07 March 2012 05:33 PM, Wolfgang Denk wrote:
Dear Prabhakar Kushwaha,
In message4F56DD59.1080304@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?
OK. after having internal discussion about different processor support. we can make this code permanently enabled.
@@ -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.
Sure, I believe we should not have any #define for this piece of code to make it consistent across the file.
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.
I will take care of this
--Prabhakar