sparc32: Implement hard_smp_processor_id() via instruction patching.
This is the last non-trivial user of btfixup.
Like sparc64, use a special patch section to resolve the various
implementations of how to read the current CPU's ID when we don't
have current_thread_info()->cpu necessarily available.
Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S
index d7143ba..773f3f0 100644
--- a/arch/sparc/kernel/entry.S
+++ b/arch/sparc/kernel/entry.S
@@ -7,6 +7,7 @@
* Copyright (C) 1997 Anton Blanchard (anton@progsoc.uts.edu.au)
*/
+#include <linux/linkage.h>
#include <linux/errno.h>
#include <asm/head.h>
@@ -1347,4 +1348,26 @@
ret
restore
+#ifdef CONFIG_SMP
+ENTRY(hard_smp_processor_id)
+661: rd %tbr, %g1
+ srl %g1, 12, %o0
+ and %o0, 3, %o0
+ .section .cpuid_patch, "ax"
+ /* Instruction location. */
+ .word 661b
+ /* SUN4D implementation. */
+ lda [%g0] ASI_M_VIKING_TMP1, %o0
+ nop
+ nop
+ /* LEON implementation. */
+ rd %asr17, %o0
+ srl %o0, 0x1c, %o0
+ nop
+ .previous
+ retl
+ nop
+ENDPROC(hard_smp_processor_id)
+#endif
+
/* End of entry.S */
