[0/2] build failure for E500 CPUs w/ CONFIG_OPROFLE=y

[Vitaly Wool]

Hello folks,

we've observed the following build failure compiling the kernel w/ oprofile on 8540 (FSL_BOOKE):

CC      arch/powerpc/oprofile/op_model_7450.o
arch/powerpc/oprofile/op_model_7450.c:62: error: conflicting types for
'pmc_start_ctrs'
include/asm/pmc.h:41: error: previous declaration of 'pmc_start_ctrs' was here
arch/powerpc/oprofile/op_model_7450.c:62: error: conflicting types for
'pmc_start_ctrs'
include/asm/pmc.h:41: error: previous declaration of 'pmc_start_ctrs' was here
arch/powerpc/oprofile/op_model_7450.c:73: warning: static declaration of
'pmc_stop_ctrs' follows non-static declaration
include/asm/pmc.h:42: warning: previous declaration of 'pmc_stop_ctrs' was here
arch/powerpc/oprofile/op_model_7450.c: In function `fsl7450_start':
arch/powerpc/oprofile/op_model_7450.c:140: warning: implicit declaration of
function `ctr_write'
arch/powerpc/oprofile/op_model_7450.c: In function `fsl7450_handle_interrupt':
arch/powerpc/oprofile/op_model_7450.c:182: warning: implicit declaration of
function `ctr_read'
make[1]: *** [arch/powerpc/oprofile/op_model_7450.o] Error 1

The thing is that op_model_7450.c is compiled when CONFIG_PPC32 is true which might be reasonable but results in conflicting functions' types when compiled w/ CONFIG_FSL_BOOKE=y. Effectively, op_model_fsl_booke.c introduces the functions with the same names as op_model_7450.c but with different declarations, and latter ones are static while former ones are not, and this can drive any compiler mad.

This message will have two *alternative* follow-up patches which are probably more likely RFCs rather than complete solutions, but still I'm sure it's reasonable to look at those, b/c those represent two different approaches and we need to decide which way to go first.

Vitaly