[ARM] nommu: manage the CP15 things

All the current CP15 access codes in ARM arch can be categorized and
conditioned by the defines as follows:

     Related operation	Safe condition
  a. any CP15 access	!CPU_CP15
  b. alignment trap	CPU_CP15_MMU
  c. D-cache(C-bit)	CPU_CP15
  d. I-cache		CPU_CP15 && !( CPU_ARM610 || CPU_ARM710 ||
				CPU_ARM720 || CPU_ARM740 ||
				CPU_XSCALE || CPU_XSC3 )
  e. alternate vector	CPU_CP15 && !CPU_ARM740
  f. TTB		CPU_CP15_MMU
  g. Domain		CPU_CP15_MMU
  h. FSR/FAR		CPU_CP15_MMU

For example, alternate vector is supported if and only if
"CPU_CP15 && !CPU_ARM740" is satisfied.

Signed-off-by: Hyok S. Choi <hyok.choi@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/asm-arm/system.h b/include/asm-arm/system.h
index c19c5b009f71..f05fbe31576c 100644
--- a/include/asm-arm/system.h
+++ b/include/asm-arm/system.h
@@ -46,6 +46,7 @@
 #define CPUID_TCM       2
 #define CPUID_TLBTYPE   3
 
+#ifdef CONFIG_CPU_CP15
 #define read_cpuid(reg)                                                 \
         ({                                                              \
                 unsigned int __val;                                     \
@@ -55,6 +56,9 @@
                     : "cc");                                            \
                 __val;                                                  \
         })
+#else
+#define read_cpuid(reg) (processor_id)
+#endif
 
 /*
  * This is used to ensure the compiler did actually allocate the register we