[POWERPC] Consolidate feature fixup code

There are currently two versions of the functions for applying the
feature fixups, one for CPU features and one for firmware features. In
addition, they are both in assembly and with separate implementations
for 32 and 64 bits. identify_cpu() is also implemented in assembly and
separately for 32 and 64 bits.

This patch replaces them with a pair of C functions. The call sites are
slightly moved on ppc64 as well to be called from C instead of from
assembly, though it's a very small change, and thus shouldn't cause any
problem.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 71 insertions, 1 deletions

diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c
index f23aad66a79e..6fdfaa4a82b8 100644
--- a/arch/powerpc/kernel/cputable.c
+++ b/arch/powerpc/kernel/cputable.c
@@ -18,6 +18,7 @@
 
 #include <asm/oprofile_impl.h>
 #include <asm/cputable.h>
+#include <asm/prom.h>           /* for PTRRELOC on ARCH=ppc */
 
 struct cpu_spec* cur_cpu_spec = NULL;
 EXPORT_SYMBOL(cur_cpu_spec);
@@ -73,7 +74,7 @@ extern void __restore_cpu_ppc970(void);
 #define PPC_FEATURE_SPE_COMP    0
 #endif
 
-struct cpu_spec cpu_specs[] = {
+static struct cpu_spec cpu_specs[] = {
 #ifdef CONFIG_PPC64
         {       /* Power3 */
                 .pvr_mask               = 0xffff0000,
@@ -1167,3 +1168,72 @@ struct cpu_spec	cpu_specs[] = {
 #endif /* !CLASSIC_PPC */
 #endif /* CONFIG_PPC32 */
 };
+
+struct cpu_spec *identify_cpu(unsigned long offset)
+{
+        struct cpu_spec *s = cpu_specs;
+        struct cpu_spec **cur = &cur_cpu_spec;
+        unsigned int pvr = mfspr(SPRN_PVR);
+        int i;
+
+        s = PTRRELOC(s);
+        cur = PTRRELOC(cur);
+
+        if (*cur != NULL)
+                return PTRRELOC(*cur);
+
+        for (i = 0; i < ARRAY_SIZE(cpu_specs); i++,s++)
+                if ((pvr & s->pvr_mask) == s->pvr_value) {
+                        *cur = cpu_specs + i;
+#ifdef CONFIG_PPC64
+                        /* ppc64 expects identify_cpu to also call setup_cpu
+                         * for that processor. I will consolidate that at a
+                         * later time, for now, just use our friend #ifdef.
+                         * we also don't need to PTRRELOC the function pointer
+                         * on ppc64 as we are running at 0 in real mode.
+                         */
+                        if (s->cpu_setup) {
+                                s->cpu_setup(offset, s);
+                        }
+#endif /* CONFIG_PPC64 */
+                        return s;
+                }
+        BUG();
+        return NULL;
+}
+
+void do_feature_fixups(unsigned long offset, unsigned long value,
+                       void *fixup_start, void *fixup_end)
+{
+        struct fixup_entry {
+                unsigned long   mask;
+                unsigned long   value;
+                unsigned int    *start;
+                unsigned int    *end;
+        } *fcur, *fend;
+
+        fcur = fixup_start;
+        fend = fixup_end;
+
+        for (; fcur < fend; fcur++) {
+                unsigned int *pstart, *pend, *p;
+
+                if ((value & fcur->mask) == fcur->value)
+                        continue;
+
+                /* These PTRRELOCs will disappear once the new scheme for
+                 * modules and vdso is implemented
+                 */
+                pstart = PTRRELOC(fcur->start);
+                pend = PTRRELOC(fcur->end);
+
+                for (p = pstart; p < pend; p++) {
+                        *p = 0x60000000u;
+                        asm volatile ("dcbst 0, %0" : : "r" (p));
+                }
+                asm volatile ("sync" : : : "memory");
+                for (p = pstart; p < pend; p++)
+                        asm volatile ("icbi 0,%0" : : "r" (p));
+                asm volatile ("sync; isync" : : : "memory");
+        }
+}