[RFC part1 PATCH 4/7] ARM64 / ACPI: Introduce the skeleton of _PDC related for ARM64

[Hanjun Guo]

The _PDC (Processor Driver Capabilities) object provides OSPM a
mechanism to convey to the platform the capabilities supported
by OSPM for processor power management.

OSPM evaluates _PDC prior to evaluating any other processor
power management objects returning configuration information.

This patch introduces the skeleton of _PDC related file to make
ACPI core can be compiled on ARM64.

Signed-off-by: Al Stone <al.stone at linaro.org>
Signed-off-by: Graeme Gregory <graeme.gregory at linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo at linaro.org>
---
 arch/arm64/include/asm/acpi.h      |   32 ++++++++++++++++++++++++++++++++
 arch/arm64/include/asm/processor.h |   11 +++++++++++
 arch/arm64/kernel/process.c        |    5 +++++
 3 files changed, 48 insertions(+)
 create mode 100644 arch/arm64/include/asm/acpi.h

diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
new file mode 100644
index 0000000..c186f5b
--- /dev/null
+++ b/arch/arm64/include/asm/acpi.h
@@ -0,0 +1,32 @@
+/*
+ *  Copyright (C) 2013, Al Stone <al.stone at linaro.org>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#ifndef _ASM_ARM_ACPI_H
+#define _ASM_ARM_ACPI_H
+
+static inline bool arch_has_acpi_pdc(void)
+{
+	return false;	/* always false for now */
+}
+
+static inline void arch_acpi_set_pdc_bits(u32 *buf)
+{
+	return;
+}
+
+#endif /*_ASM_ARM_ACPI_H*/
diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
index 45b20cd..73b1d3a 100644
--- a/arch/arm64/include/asm/processor.h
+++ b/arch/arm64/include/asm/processor.h
@@ -162,6 +162,17 @@ static inline void spin_lock_prefetch(const void *x)
 
 #define HAVE_ARCH_PICK_MMAP_LAYOUT
 
+#ifdef CONFIG_ACPI
+/*
+ * FIXME: there is no MWAIT on ARM, should be WFI or something else,
+ * and modify drivers/acpi/processor_core.c too.
+ */
+enum idle_boot_override { IDLE_NO_OVERRIDE = 0, IDLE_HALT, IDLE_NOMWAIT,
+			IDLE_POLL, IDLE_FORCE_MWAIT };
+
+extern unsigned long    boot_option_idle_override;
+#endif
+
 #endif
 
 #endif /* __ASM_PROCESSOR_H */
diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
index de17c89..2cd4182 100644
--- a/arch/arm64/kernel/process.c
+++ b/arch/arm64/kernel/process.c
@@ -347,3 +347,8 @@ unsigned long randomize_et_dyn(unsigned long base)
 {
 	return randomize_base(base);
 }
+
+#ifdef CONFIG_ACPI
+unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE;
+EXPORT_SYMBOL(boot_option_idle_override);
+#endif
-- 
1.7.9.5