1 files changed, 74 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/epapr_paravirt.c b/arch/powerpc/kernel/epapr_paravirt.c
new file mode 100644
index 000000000..d4b8aff20
--- /dev/null
+++ b/arch/powerpc/kernel/epapr_paravirt.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ePAPR para-virtualization support.
+ *
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ */
+
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <asm/epapr_hcalls.h>
+#include <asm/cacheflush.h>
+#include <asm/code-patching.h>
+#include <asm/machdep.h>
+#include <asm/inst.h>
+
+#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64)
+extern void epapr_ev_idle(void);
+extern u32 epapr_ev_idle_start[];
+#endif
+
+bool epapr_paravirt_enabled;
+static bool __maybe_unused epapr_has_idle;
+
+static int __init early_init_dt_scan_epapr(unsigned long node,
+					   const char *uname,
+					   int depth, void *data)
+{
+	const u32 *insts;
+	int len;
+	int i;
+
+	insts = of_get_flat_dt_prop(node, "hcall-instructions", &len);
+	if (!insts)
+		return 0;
+
+	if (len % 4 || len > (4 * 4))
+		return -1;
+
+	for (i = 0; i < (len / 4); i++) {
+		ppc_inst_t inst = ppc_inst(be32_to_cpu(insts[i]));
+		patch_instruction(epapr_hypercall_start + i, inst);
+#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64)
+		patch_instruction(epapr_ev_idle_start + i, inst);
+#endif
+	}
+
+#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64)
+	if (of_get_flat_dt_prop(node, "has-idle", NULL))
+		epapr_has_idle = true;
+#endif
+
+	epapr_paravirt_enabled = true;
+
+	return 1;
+}
+
+int __init epapr_paravirt_early_init(void)
+{
+	of_scan_flat_dt(early_init_dt_scan_epapr, NULL);
+
+	return 0;
+}
+
+static int __init epapr_idle_init(void)
+{
+#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64)
+	if (epapr_has_idle)
+		ppc_md.power_save = epapr_ev_idle;
+#endif
+
+	return 0;
+}
+
+postcore_initcall(epapr_idle_init);