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-rw-r--r--arch/powerpc/kernel/vdso/getcpu.S50
1 files changed, 50 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/vdso/getcpu.S b/arch/powerpc/kernel/vdso/getcpu.S
new file mode 100644
index 000000000000..8e08ccf19062
--- /dev/null
+++ b/arch/powerpc/kernel/vdso/getcpu.S
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *
+ * Copyright (C) IBM Corporation, 2012
+ *
+ * Author: Anton Blanchard <anton@au.ibm.com>
+ */
+#include <asm/ppc_asm.h>
+#include <asm/vdso.h>
+
+ .text
+/*
+ * Exact prototype of getcpu
+ *
+ * int __kernel_getcpu(unsigned *cpu, unsigned *node);
+ *
+ */
+#if defined(CONFIG_PPC64)
+V_FUNCTION_BEGIN(__kernel_getcpu)
+ .cfi_startproc
+ mfspr r5,SPRN_SPRG_VDSO_READ
+ PPC_LCMPI cr0,r3,0
+ PPC_LCMPI cr1,r4,0
+ clrlwi r6,r5,16
+ rlwinm r7,r5,16,31-15,31-0
+ beq cr0,1f
+ stw r6,0(r3)
+1: crclr cr0*4+so
+ li r3,0 /* always success */
+ beqlr cr1
+ stw r7,0(r4)
+ blr
+ .cfi_endproc
+V_FUNCTION_END(__kernel_getcpu)
+#elif !defined(CONFIG_SMP)
+V_FUNCTION_BEGIN(__kernel_getcpu)
+ .cfi_startproc
+ cmpwi cr0, r3, 0
+ cmpwi cr1, r4, 0
+ li r5, 0
+ beq cr0, 1f
+ stw r5, 0(r3)
+1: li r3, 0 /* always success */
+ crclr cr0*4+so
+ beqlr cr1
+ stw r5, 0(r4)
+ blr
+ .cfi_endproc
+V_FUNCTION_END(__kernel_getcpu)
+#endif