[U-Boot] [RFC][PATCH 17/19] arm cp15: setup mmu and enable dcache

[Alessandro Rubini <rubini@gnudd.com>]

Thanks Heiko for picking these up, wanted to reply today offlist.

Nick Thompson:
> As you noted, not all boards define these two symbols. I don't see where you
> have added them in the config.h files.

When I've done this, I couldn't find a name that all boards were
using, so I had to make a choice. I think I just counted the various
names and picked the more common.  A board enabling cache must ensure
to have the correct names defined, I see no easy solution.

   tornado% grep -rl CONFIG_SYS_SDRAM_BASE include/configs | wc -l
   353
   tornado% grep -rL CONFIG_SYS_SDRAM_BASE include/configs/ | wc -l
   193

For example integratorcp is in this "grep -L", and it has
PHYS_SDRAM_1/PHYS_SDRAM_1_SIZE . This matches less than half of those 193
boards:

   tornado% grep -rl PHYS_SDRAM_1_SIZE include/configs/ | wc -l
   86

However, re-reading the patch looks like I chose the wrong symbol.
This ought to be fixed, I'll try next week to address the issue.

>> +		page_table[i] = i << 20 | (3 << 10) | 0x1e;
> 
> These numbers ought to be defines, no?

Yes, it was a lazy RFC. I'll clean up ASAP (monday, hopefully),
unless Heiko does it in his tree.  Writeback or writethtough should
be selectable.

> I have previously tested this patch on da830 and it works fine, bar the two
> issues above.

Thanks for testing and your feedback
/alessandro