You do understand that readl is in fact a call to in_le32() on ppc
(cf. include/asm-ppc/io.h).
=20
The question now is, what endianness you would like in that register?
Regards
--=20
Stephane
Dear Stephane:
Your point is well made. I can see that readl is in fact a call to
in_le32. Maybe there is a more basic problem here.=20
If I change the call to readl to a call to in_be32, things make sense
again. So, maybe I don't quite understand the endianness setup of this
Linux project.
I am told that we are running this ppc in big endian, so would this mean
that readl & writel should actually be resolving to in_be32/out_be32
respectively? Is there some other setup that may be wrong?
Charles
On Mar 5, 2007, at 9:02 AM, Charles Krinke wrote:
You do understand that readl is in fact a call to in_le32() on ppc
(cf. include/asm-ppc/io.h).
The question now is, what endianness you would like in that register?
Regards
--
Stephane
Dear Stephane:
Your point is well made. I can see that readl is in fact a call to
in_le32. Maybe there is a more basic problem here.
If I change the call to readl to a call to in_be32, things make sense
again. So, maybe I don't quite understand the endianness setup of this
Linux project.
readl/writel are for PCI bus accesses. PCI is inherently little endian.
I am told that we are running this ppc in big endian, so would this
mean
that readl & writel should actually be resolving to in_be32/out_be32
respectively? Is there some other setup that may be wrong?
Nope, readl/writel are doing the write thing, they will ALWAYS be
little endian.
You truly want in_be*/out_be* when accessing 85xx CCSR registers
since all of them are big endian.
- k