powerpc/85xx: p2020rdb - move the NAND address.

[Kumar Gala]

On Mar 29, 2012, at 2:26 AM, Sebastian Andrzej Siewior wrote:

> On 03/28/2012 10:30 PM, Bryan Hundven wrote:
>> > It is not at 0xffa00000. According to current u-boot source the NAND
>> > controller is always at 0xff800000 and it is either at CS0 or CS1
>> > depending on NAND or NAND+NOR mode. In 36bit mode it is shifted to
>> > 0xfff800000 but it has always an eight there and never an A.
>> >
>> > Signed-off-by: Sebastian Andrzej Siewior <bigeasy at linutronix.de>
>> > Signed-off-by: Kumar Gala <galak at kernel.crashing.org>
>> 
>> I am having a hard time verifying this change. I don't think you are
>> wrong, I'm just having a hard time following.
>> 
>> I do not see where this has always been 0xff800000 in u-boot.
> 
> <cut>
> 
>> But while I was checking changes in arch/powerpc/, I found this change
>> and wanted to understand why 0xffa00000 has worked for us for so long?
> 
> Kumar, I wasn't wrong entirely I just missed one detail. U-Boot
> provides two different configs, not just one define like its for
> SPL/SPI/...:
> 
> - include/configs/P1_P2_RDB.h
> 
> #ifndef CONFIG_NAND_SPL
> #define CONFIG_SYS_NAND_BASE            0xffa00000
> #ifdef CONFIG_PHYS_64BIT
> #define CONFIG_SYS_NAND_BASE_PHYS       0xfffa00000ull
> #else
> #define CONFIG_SYS_NAND_BASE_PHYS       CONFIG_SYS_NAND_BASE
> #endif
> #else
> #define CONFIG_SYS_NAND_BASE            0xfff00000
> #ifdef CONFIG_PHYS_64BIT
> #define CONFIG_SYS_NAND_BASE_PHYS       0xffff00000ull
> #else
> #define CONFIG_SYS_NAND_BASE_PHYS       CONFIG_SYS_NAND_BASE
> #endif
> #endif
> 
> - include/configs/p1_p2_rdb_pc.h
> 
> #ifdef CONFIG_NAND_FSL_ELBC
> #define CONFIG_SYS_NAND_BASE            0xff800000
> #ifdef CONFIG_PHYS_64BIT
> #define CONFIG_SYS_NAND_BASE_PHYS       0xfff800000ull
> #else
> #define CONFIG_SYS_NAND_BASE_PHYS       CONFIG_SYS_NAND_BASE
> #endif
> 
> and for kernel they use both the same device tree. So with the change,
> the _pc variant finds its flash. Before that it worked for the non-pc
> variant only if NAND_SPL wasn't used.
> Any suggestion on fixing that? Providing a new dt for _pc would "fix"
> it but the non pc variant won't find it in the case of NAND_SPL.

There are two (well 3 since rdb-pc has both 32b & 36b) in the tree now:

arch/powerpc/boot/dts/p2020rdb.dts
arch/powerpc/boot/dts/p2020rdb-pc_32b.dts
arch/powerpc/boot/dts/p2020rdb-pc_36b.dts

> 
> Since both system have the same SoC and the NAND_SPL is always linked
> against 0xfff00000 I don't see anything wrong to relocate the NAND CS
> later to 0xff800000 (or to 0xffa00000) and having it consistent among
> both configs.


- k