MIPS: Optimize current_cpu_type() for better code.

 o Move current_cpu_type() to a separate header file
 o #ifdefing on supported CPU types lets modern GCC know that certain
   code in callers may be discarded ideally turning current_cpu_type() into
   a function returning a constant.
 o Use current_cpu_type() rather than direct access to struct cpuinfo_mips.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5833/

1 files changed, 4 insertions, 2 deletions

diff --git a/arch/mips/mm/c-octeon.c b/arch/mips/mm/c-octeon.c
index 729e7702b1de..c8efdb5b6ee0 100644
--- a/arch/mips/mm/c-octeon.c
+++ b/arch/mips/mm/c-octeon.c
@@ -19,6 +19,7 @@
 #include <asm/bootinfo.h>
 #include <asm/cacheops.h>
 #include <asm/cpu-features.h>
+#include <asm/cpu-type.h>
 #include <asm/page.h>
 #include <asm/pgtable.h>
 #include <asm/r4kcache.h>
@@ -186,9 +187,10 @@ static void probe_octeon(void)
         unsigned long dcache_size;
         unsigned int config1;
         struct cpuinfo_mips *c = &current_cpu_data;
+        int cputype = current_cpu_type();
 
         config1 = read_c0_config1();
-        switch (c->cputype) {
+        switch (cputype) {
         case CPU_CAVIUM_OCTEON:
         case CPU_CAVIUM_OCTEON_PLUS:
                 c->icache.linesz = 2 << ((config1 >> 19) & 7);
@@ -199,7 +201,7 @@ static void probe_octeon(void)
                         c->icache.sets * c->icache.ways * c->icache.linesz;
                 c->icache.waybit = ffs(icache_size / c->icache.ways) - 1;
                 c->dcache.linesz = 128;
-                if (c->cputype == CPU_CAVIUM_OCTEON_PLUS)
+                if (cputype == CPU_CAVIUM_OCTEON_PLUS)
                         c->dcache.sets = 2; /* CN5XXX has two Dcache sets */
                 else
                         c->dcache.sets = 1; /* CN3XXX has one Dcache set */