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-rw-r--r--arch/powerpc/kernel/epapr_hcalls.S52
1 files changed, 52 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/epapr_hcalls.S b/arch/powerpc/kernel/epapr_hcalls.S
new file mode 100644
index 000000000..69a912550
--- /dev/null
+++ b/arch/powerpc/kernel/epapr_hcalls.S
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ */
+
+#include <linux/threads.h>
+#include <asm/epapr_hcalls.h>
+#include <asm/reg.h>
+#include <asm/page.h>
+#include <asm/cputable.h>
+#include <asm/thread_info.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-compat.h>
+#include <asm/asm-offsets.h>
+#include <asm/export.h>
+
+#ifndef CONFIG_PPC64
+/* epapr_ev_idle() was derived from e500_idle() */
+_GLOBAL(epapr_ev_idle)
+ PPC_LL r4, TI_LOCAL_FLAGS(r2) /* set napping bit */
+ ori r4, r4,_TLF_NAPPING /* so when we take an exception */
+ PPC_STL r4, TI_LOCAL_FLAGS(r2) /* it will return to our caller */
+
+ wrteei 1
+
+idle_loop:
+ LOAD_REG_IMMEDIATE(r11, EV_HCALL_TOKEN(EV_IDLE))
+
+.global epapr_ev_idle_start
+epapr_ev_idle_start:
+ li r3, -1
+ nop
+ nop
+ nop
+
+ /*
+ * Guard against spurious wakeups from a hypervisor --
+ * only interrupt will cause us to return to LR due to
+ * _TLF_NAPPING.
+ */
+ b idle_loop
+#endif
+
+/* Hypercall entry point. Will be patched with device tree instructions. */
+.global epapr_hypercall_start
+epapr_hypercall_start:
+ li r3, -1
+ nop
+ nop
+ nop
+ blr
+EXPORT_SYMBOL(epapr_hypercall_start)