[PATCH 2/7] arm64: ACPI: move kernel acpi files to a directory

[al.stone@linaro.org]

From: Al Stone <ahs3@redhat.com>

In preparation for adding some additional arch-dependent ACPI files,
move the existing ones to a directory to try to keep clutter down in
the arch/arm64/kernel directory.

There is no functional change.  This patch only moves source files.

Signed-off-by: Al Stone <al.stone@linaro.org>
---
 arch/arm64/kernel/Makefile      |   2 +-
 arch/arm64/kernel/acpi.c        | 359 ----------------------------------------
 arch/arm64/kernel/acpi/Makefile |   1 +
 arch/arm64/kernel/acpi/acpi.c   | 359 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 361 insertions(+), 360 deletions(-)
 delete mode 100644 arch/arm64/kernel/acpi.c
 create mode 100644 arch/arm64/kernel/acpi/Makefile
 create mode 100644 arch/arm64/kernel/acpi/acpi.c

diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 8bdc6bd..d7d622f 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -34,7 +34,7 @@ arm64-obj-$(CONFIG_KGDB)		+= kgdb.o
 arm64-obj-$(CONFIG_EFI)			+= efi.o efi-stub.o efi-entry.o
 arm64-obj-$(CONFIG_PCI)			+= pci.o
 arm64-obj-$(CONFIG_ARMV8_DEPRECATED)	+= armv8_deprecated.o
-arm64-obj-$(CONFIG_ACPI)		+= acpi.o
+arm64-obj-$(CONFIG_ACPI)		+= acpi/
 
 obj-y					+= $(arm64-obj-y) vdso/
 obj-m					+= $(arm64-obj-m)
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
deleted file mode 100644
index ea3c9fc..0000000
--- a/arch/arm64/kernel/acpi.c
+++ /dev/null
@@ -1,359 +0,0 @@
-/*
- *  ARM64 Specific Low-Level ACPI Boot Support
- *
- *  Copyright (C) 2013-2014, Linaro Ltd.
- *	Author: Al Stone <al.stone@linaro.org>
- *	Author: Graeme Gregory <graeme.gregory@linaro.org>
- *	Author: Hanjun Guo <hanjun.guo@linaro.org>
- *	Author: Tomasz Nowicki <tomasz.nowicki@linaro.org>
- *	Author: Naresh Bhat <naresh.bhat@linaro.org>
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License version 2 as
- *  published by the Free Software Foundation.
- */
-
-#define pr_fmt(fmt) "ACPI: " fmt
-
-#include <linux/init.h>
-#include <linux/acpi.h>
-#include <linux/cpumask.h>
-#include <linux/memblock.h>
-#include <linux/irq.h>
-#include <linux/irqdomain.h>
-#include <linux/bootmem.h>
-#include <linux/smp.h>
-#include <linux/irqchip/arm-gic-acpi.h>
-
-#include <asm/cputype.h>
-#include <asm/cpu_ops.h>
-
-int acpi_noirq;			/* skip ACPI IRQ initialization */
-int acpi_disabled;
-EXPORT_SYMBOL(acpi_disabled);
-
-int acpi_pci_disabled;		/* skip ACPI PCI scan and IRQ initialization */
-EXPORT_SYMBOL(acpi_pci_disabled);
-
-static int enabled_cpus;	/* Processors (GICC) with enabled flag in MADT */
-
-/*
- * Since we're on ARM, the default interrupt routing model
- * clearly has to be GIC.
- */
-enum acpi_irq_model_id acpi_irq_model = ACPI_IRQ_MODEL_GIC;
-
-/*
- * __acpi_map_table() will be called before page_init(), so early_ioremap()
- * or early_memremap() should be called here to for ACPI table mapping.
- */
-char *__init __acpi_map_table(unsigned long phys, unsigned long size)
-{
-	if (!phys || !size)
-		return NULL;
-
-	return early_memremap(phys, size);
-}
-
-void __init __acpi_unmap_table(char *map, unsigned long size)
-{
-	if (!map || !size)
-		return;
-
-	early_memunmap(map, size);
-}
-
-/**
- * acpi_map_gic_cpu_interface - generates a logical cpu number
- * and map to MPIDR represented by GICC structure
- * @mpidr: CPU's hardware id to register, MPIDR represented in MADT
- * @enabled: this cpu is enabled or not
- *
- * Returns the logical cpu number which maps to MPIDR
- */
-static int acpi_map_gic_cpu_interface(u64 mpidr, u8 enabled)
-{
-	int cpu;
-
-	if (mpidr == INVALID_HWID) {
-		pr_info("Skip MADT cpu entry with invalid MPIDR\n");
-		return -EINVAL;
-	}
-
-	total_cpus++;
-	if (!enabled)
-		return -EINVAL;
-
-	if (enabled_cpus >=  NR_CPUS) {
-		pr_warn("NR_CPUS limit of %d reached, Processor %d/0x%llx ignored.\n",
-			NR_CPUS, total_cpus, mpidr);
-		return -EINVAL;
-	}
-
-	/* No need to check duplicate MPIDRs for the first CPU */
-	if (enabled_cpus) {
-		/*
-		 * Duplicate MPIDRs are a recipe for disaster. Scan
-		 * all initialized entries and check for
-		 * duplicates. If any is found just ignore the CPU.
-		 */
-		for_each_possible_cpu(cpu) {
-			if (cpu_logical_map(cpu) == mpidr) {
-				pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
-				       mpidr);
-				return -EINVAL;
-			}
-		}
-
-		/* allocate a logical cpu id for the new comer */
-		cpu = cpumask_next_zero(-1, cpu_possible_mask);
-	} else {
-		/*
-		 * First GICC entry must be BSP as ACPI spec said
-		 * in section 5.2.12.15
-		 */
-		if  (cpu_logical_map(0) != mpidr) {
-			pr_err("First GICC entry with MPIDR 0x%llx is not BSP\n",
-			       mpidr);
-			return -EINVAL;
-		}
-
-		/*
-		 * boot_cpu_init() already hold bit 0 in cpu_present_mask
-		 * for BSP, no need to allocate again.
-		 */
-		cpu = 0;
-	}
-
-	/* CPU 0 was already initialized */
-	if (cpu) {
-		cpu_ops[cpu] = cpu_get_ops(acpi_psci_present() ? "psci" : NULL);
-		if (!cpu_ops[cpu])
-			return -EINVAL;
-
-		if (cpu_ops[cpu]->cpu_init(NULL, cpu))
-			return -EOPNOTSUPP;
-
-		/* map the logical cpu id to cpu MPIDR */
-		cpu_logical_map(cpu) = mpidr;
-
-		set_cpu_possible(cpu, true);
-	} else {
-		/* get cpu0's ops, no need to return if ops is null */
-		cpu_ops[0] = cpu_get_ops(acpi_psci_present() ? "psci" : NULL);
-	}
-
-	enabled_cpus++;
-	return cpu;
-}
-
-static int __init
-acpi_parse_gic_cpu_interface(struct acpi_subtable_header *header,
-				const unsigned long end)
-{
-	struct acpi_madt_generic_interrupt *processor;
-
-	processor = (struct acpi_madt_generic_interrupt *)header;
-
-	if (BAD_MADT_ENTRY(processor, end))
-		return -EINVAL;
-
-	acpi_table_print_madt_entry(header);
-
-	acpi_map_gic_cpu_interface(processor->arm_mpidr & MPIDR_HWID_BITMASK,
-		processor->flags & ACPI_MADT_ENABLED);
-
-	return 0;
-}
-
-/* Parse GIC cpu interface entries in MADT for SMP init */
-void __init acpi_smp_init_cpus(void)
-{
-	int count;
-
-	/*
-	 * do a partial walk of MADT to determine how many CPUs
-	 * we have including disabled CPUs, and get information
-	 * we need for SMP init
-	 */
-	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
-			acpi_parse_gic_cpu_interface, 0);
-
-	if (!count) {
-		pr_err("No GIC CPU interface entries present\n");
-		return;
-	} else if (count < 0) {
-		pr_err("Error parsing GIC CPU interface entry\n");
-		return;
-	}
-
-	/* Make boot-up look pretty */
-	pr_info("%d CPUs enabled, %d CPUs total\n", enabled_cpus, total_cpus);
-}
-
-int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
-{
-	*irq = irq_find_mapping(NULL, gsi);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
-
-/*
- * success: return IRQ number (>0)
- * failure: return =< 0
- */
-int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity)
-{
-	unsigned int irq;
-	unsigned int irq_type;
-
-	/*
-	 * ACPI have no bindings to indicate SPI or PPI, so we
-	 * use different mappings from DT in ACPI.
-	 *
-	 * For FDT
-	 * PPI interrupt: in the range [0, 15];
-	 * SPI interrupt: in the range [0, 987];
-	 *
-	 * For ACPI, GSI should be unique so using
-	 * the hwirq directly for the mapping:
-	 * PPI interrupt: in the range [16, 31];
-	 * SPI interrupt: in the range [32, 1019];
-	 */
-
-	if (trigger == ACPI_EDGE_SENSITIVE &&
-				polarity == ACPI_ACTIVE_LOW)
-		irq_type = IRQ_TYPE_EDGE_FALLING;
-	else if (trigger == ACPI_EDGE_SENSITIVE &&
-				polarity == ACPI_ACTIVE_HIGH)
-		irq_type = IRQ_TYPE_EDGE_RISING;
-	else if (trigger == ACPI_LEVEL_SENSITIVE &&
-				polarity == ACPI_ACTIVE_LOW)
-		irq_type = IRQ_TYPE_LEVEL_LOW;
-	else if (trigger == ACPI_LEVEL_SENSITIVE &&
-				polarity == ACPI_ACTIVE_HIGH)
-		irq_type = IRQ_TYPE_LEVEL_HIGH;
-	else
-		irq_type = IRQ_TYPE_NONE;
-
-	/*
-	 * Since only one GIC is supported in ACPI 5.0, we can
-	 * create mapping refer to the default domain
-	 */
-	irq = irq_create_mapping(NULL, gsi);
-	if (!irq)
-		return irq;
-
-	/* Set irq type if specified and different than the current one */
-	if (irq_type != IRQ_TYPE_NONE &&
-		irq_type != irq_get_trigger_type(irq))
-		irq_set_irq_type(irq, irq_type);
-	return irq;
-}
-EXPORT_SYMBOL_GPL(acpi_register_gsi);
-
-void acpi_unregister_gsi(u32 gsi)
-{
-}
-EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
-
-static int __init acpi_parse_fadt(struct acpi_table_header *table)
-{
-	struct acpi_table_fadt *fadt = (struct acpi_table_fadt *)table;
-
-	/*
-	 * Revision in table header is the FADT Major revision,
-	 * and there is a minor revision of FADT which was introduced
-	 * by ACPI 5.1, we only deal with ACPI 5.1 or newer revision
-	 * to get arm boot flags, or we will disable ACPI.
-	 */
-	if (table->revision > 5 ||
-	    (table->revision == 5 && fadt->minor_revision >= 1)) {
-		/*
-		 * ACPI 5.1 only has two explicit methods to boot up SMP,
-		 * PSCI and Parking protocol, but the Parking protocol is
-		 * only specified for ARMv7 now, so make PSCI as the only
-		 * way for the SMP boot protocol before some updates for
-		 * the ACPI spec or the Parking protocol spec.
-		 */
-		if (acpi_psci_present())
-			return 0;
-
-		pr_warn("No PSCI support, will not bring up secondary CPUs\n");
-		return -EOPNOTSUPP;
-	}
-
-	pr_warn("Unsupported FADT revision %d.%d, should be 5.1+, will disable ACPI\n",
-		table->revision, fadt->minor_revision);
-	disable_acpi();
-
-	return -EINVAL;
-}
-
-/*
- * acpi_boot_table_init() called from setup_arch(), always.
- *	1. find RSDP and get its address, and then find XSDT
- *	2. extract all tables and checksums them all
- *	3. check ACPI FADT revision
- *
- * We can parse ACPI boot-time tables such as MADT after
- * this function is called.
- */
-void __init acpi_boot_table_init(void)
-{
-	/* If acpi_disabled, bail out */
-	if (acpi_disabled)
-		return;
-
-	/* Initialize the ACPI boot-time table parser. */
-	if (acpi_table_init()) {
-		disable_acpi();
-		return;
-	}
-
-	if (acpi_table_parse(ACPI_SIG_FADT, acpi_parse_fadt))
-		pr_err("Can't find FADT or error happened during parsing FADT\n");
-}
-
-void __init acpi_gic_init(void)
-{
-	struct acpi_table_header *table;
-	acpi_status status;
-	acpi_size tbl_size;
-	int err;
-
-	if (acpi_disabled)
-		return;
-
-	status = acpi_get_table_with_size(ACPI_SIG_MADT, 0, &table, &tbl_size);
-	if (ACPI_FAILURE(status)) {
-		const char *msg = acpi_format_exception(status);
-
-		pr_err("Failed to get MADT table, %s\n", msg);
-		return;
-	}
-
-	err = gic_v2_acpi_init(table);
-	if (err)
-		pr_err("Failed to initialize GIC IRQ controller");
-
-	early_acpi_os_unmap_memory((char *)table, tbl_size);
-}
-
-static int __init parse_acpi(char *arg)
-{
-	if (!arg)
-		return -EINVAL;
-
-	/* "acpi=off" disables both ACPI table parsing and interpreter */
-	if (strcmp(arg, "off") == 0)
-		disable_acpi();
-	else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */
-		enable_acpi();
-	else
-		return -EINVAL;	/* Core will print when we return error */
-
-	return 0;
-}
-early_param("acpi", parse_acpi);
diff --git a/arch/arm64/kernel/acpi/Makefile b/arch/arm64/kernel/acpi/Makefile
new file mode 100644
index 0000000..e049f94
--- /dev/null
+++ b/arch/arm64/kernel/acpi/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_ACPI)		+= acpi.o
diff --git a/arch/arm64/kernel/acpi/acpi.c b/arch/arm64/kernel/acpi/acpi.c
new file mode 100644
index 0000000..ea3c9fc
--- /dev/null
+++ b/arch/arm64/kernel/acpi/acpi.c
@@ -0,0 +1,359 @@
+/*
+ *  ARM64 Specific Low-Level ACPI Boot Support
+ *
+ *  Copyright (C) 2013-2014, Linaro Ltd.
+ *	Author: Al Stone <al.stone@linaro.org>
+ *	Author: Graeme Gregory <graeme.gregory@linaro.org>
+ *	Author: Hanjun Guo <hanjun.guo@linaro.org>
+ *	Author: Tomasz Nowicki <tomasz.nowicki@linaro.org>
+ *	Author: Naresh Bhat <naresh.bhat@linaro.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+#define pr_fmt(fmt) "ACPI: " fmt
+
+#include <linux/init.h>
+#include <linux/acpi.h>
+#include <linux/cpumask.h>
+#include <linux/memblock.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/bootmem.h>
+#include <linux/smp.h>
+#include <linux/irqchip/arm-gic-acpi.h>
+
+#include <asm/cputype.h>
+#include <asm/cpu_ops.h>
+
+int acpi_noirq;			/* skip ACPI IRQ initialization */
+int acpi_disabled;
+EXPORT_SYMBOL(acpi_disabled);
+
+int acpi_pci_disabled;		/* skip ACPI PCI scan and IRQ initialization */
+EXPORT_SYMBOL(acpi_pci_disabled);
+
+static int enabled_cpus;	/* Processors (GICC) with enabled flag in MADT */
+
+/*
+ * Since we're on ARM, the default interrupt routing model
+ * clearly has to be GIC.
+ */
+enum acpi_irq_model_id acpi_irq_model = ACPI_IRQ_MODEL_GIC;
+
+/*
+ * __acpi_map_table() will be called before page_init(), so early_ioremap()
+ * or early_memremap() should be called here to for ACPI table mapping.
+ */
+char *__init __acpi_map_table(unsigned long phys, unsigned long size)
+{
+	if (!phys || !size)
+		return NULL;
+
+	return early_memremap(phys, size);
+}
+
+void __init __acpi_unmap_table(char *map, unsigned long size)
+{
+	if (!map || !size)
+		return;
+
+	early_memunmap(map, size);
+}
+
+/**
+ * acpi_map_gic_cpu_interface - generates a logical cpu number
+ * and map to MPIDR represented by GICC structure
+ * @mpidr: CPU's hardware id to register, MPIDR represented in MADT
+ * @enabled: this cpu is enabled or not
+ *
+ * Returns the logical cpu number which maps to MPIDR
+ */
+static int acpi_map_gic_cpu_interface(u64 mpidr, u8 enabled)
+{
+	int cpu;
+
+	if (mpidr == INVALID_HWID) {
+		pr_info("Skip MADT cpu entry with invalid MPIDR\n");
+		return -EINVAL;
+	}
+
+	total_cpus++;
+	if (!enabled)
+		return -EINVAL;
+
+	if (enabled_cpus >=  NR_CPUS) {
+		pr_warn("NR_CPUS limit of %d reached, Processor %d/0x%llx ignored.\n",
+			NR_CPUS, total_cpus, mpidr);
+		return -EINVAL;
+	}
+
+	/* No need to check duplicate MPIDRs for the first CPU */
+	if (enabled_cpus) {
+		/*
+		 * Duplicate MPIDRs are a recipe for disaster. Scan
+		 * all initialized entries and check for
+		 * duplicates. If any is found just ignore the CPU.
+		 */
+		for_each_possible_cpu(cpu) {
+			if (cpu_logical_map(cpu) == mpidr) {
+				pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
+				       mpidr);
+				return -EINVAL;
+			}
+		}
+
+		/* allocate a logical cpu id for the new comer */
+		cpu = cpumask_next_zero(-1, cpu_possible_mask);
+	} else {
+		/*
+		 * First GICC entry must be BSP as ACPI spec said
+		 * in section 5.2.12.15
+		 */
+		if  (cpu_logical_map(0) != mpidr) {
+			pr_err("First GICC entry with MPIDR 0x%llx is not BSP\n",
+			       mpidr);
+			return -EINVAL;
+		}
+
+		/*
+		 * boot_cpu_init() already hold bit 0 in cpu_present_mask
+		 * for BSP, no need to allocate again.
+		 */
+		cpu = 0;
+	}
+
+	/* CPU 0 was already initialized */
+	if (cpu) {
+		cpu_ops[cpu] = cpu_get_ops(acpi_psci_present() ? "psci" : NULL);
+		if (!cpu_ops[cpu])
+			return -EINVAL;
+
+		if (cpu_ops[cpu]->cpu_init(NULL, cpu))
+			return -EOPNOTSUPP;
+
+		/* map the logical cpu id to cpu MPIDR */
+		cpu_logical_map(cpu) = mpidr;
+
+		set_cpu_possible(cpu, true);
+	} else {
+		/* get cpu0's ops, no need to return if ops is null */
+		cpu_ops[0] = cpu_get_ops(acpi_psci_present() ? "psci" : NULL);
+	}
+
+	enabled_cpus++;
+	return cpu;
+}
+
+static int __init
+acpi_parse_gic_cpu_interface(struct acpi_subtable_header *header,
+				const unsigned long end)
+{
+	struct acpi_madt_generic_interrupt *processor;
+
+	processor = (struct acpi_madt_generic_interrupt *)header;
+
+	if (BAD_MADT_ENTRY(processor, end))
+		return -EINVAL;
+
+	acpi_table_print_madt_entry(header);
+
+	acpi_map_gic_cpu_interface(processor->arm_mpidr & MPIDR_HWID_BITMASK,
+		processor->flags & ACPI_MADT_ENABLED);
+
+	return 0;
+}
+
+/* Parse GIC cpu interface entries in MADT for SMP init */
+void __init acpi_smp_init_cpus(void)
+{
+	int count;
+
+	/*
+	 * do a partial walk of MADT to determine how many CPUs
+	 * we have including disabled CPUs, and get information
+	 * we need for SMP init
+	 */
+	count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
+			acpi_parse_gic_cpu_interface, 0);
+
+	if (!count) {
+		pr_err("No GIC CPU interface entries present\n");
+		return;
+	} else if (count < 0) {
+		pr_err("Error parsing GIC CPU interface entry\n");
+		return;
+	}
+
+	/* Make boot-up look pretty */
+	pr_info("%d CPUs enabled, %d CPUs total\n", enabled_cpus, total_cpus);
+}
+
+int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
+{
+	*irq = irq_find_mapping(NULL, gsi);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
+
+/*
+ * success: return IRQ number (>0)
+ * failure: return =< 0
+ */
+int acpi_register_gsi(struct device *dev, u32 gsi, int trigger, int polarity)
+{
+	unsigned int irq;
+	unsigned int irq_type;
+
+	/*
+	 * ACPI have no bindings to indicate SPI or PPI, so we
+	 * use different mappings from DT in ACPI.
+	 *
+	 * For FDT
+	 * PPI interrupt: in the range [0, 15];
+	 * SPI interrupt: in the range [0, 987];
+	 *
+	 * For ACPI, GSI should be unique so using
+	 * the hwirq directly for the mapping:
+	 * PPI interrupt: in the range [16, 31];
+	 * SPI interrupt: in the range [32, 1019];
+	 */
+
+	if (trigger == ACPI_EDGE_SENSITIVE &&
+				polarity == ACPI_ACTIVE_LOW)
+		irq_type = IRQ_TYPE_EDGE_FALLING;
+	else if (trigger == ACPI_EDGE_SENSITIVE &&
+				polarity == ACPI_ACTIVE_HIGH)
+		irq_type = IRQ_TYPE_EDGE_RISING;
+	else if (trigger == ACPI_LEVEL_SENSITIVE &&
+				polarity == ACPI_ACTIVE_LOW)
+		irq_type = IRQ_TYPE_LEVEL_LOW;
+	else if (trigger == ACPI_LEVEL_SENSITIVE &&
+				polarity == ACPI_ACTIVE_HIGH)
+		irq_type = IRQ_TYPE_LEVEL_HIGH;
+	else
+		irq_type = IRQ_TYPE_NONE;
+
+	/*
+	 * Since only one GIC is supported in ACPI 5.0, we can
+	 * create mapping refer to the default domain
+	 */
+	irq = irq_create_mapping(NULL, gsi);
+	if (!irq)
+		return irq;
+
+	/* Set irq type if specified and different than the current one */
+	if (irq_type != IRQ_TYPE_NONE &&
+		irq_type != irq_get_trigger_type(irq))
+		irq_set_irq_type(irq, irq_type);
+	return irq;
+}
+EXPORT_SYMBOL_GPL(acpi_register_gsi);
+
+void acpi_unregister_gsi(u32 gsi)
+{
+}
+EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
+
+static int __init acpi_parse_fadt(struct acpi_table_header *table)
+{
+	struct acpi_table_fadt *fadt = (struct acpi_table_fadt *)table;
+
+	/*
+	 * Revision in table header is the FADT Major revision,
+	 * and there is a minor revision of FADT which was introduced
+	 * by ACPI 5.1, we only deal with ACPI 5.1 or newer revision
+	 * to get arm boot flags, or we will disable ACPI.
+	 */
+	if (table->revision > 5 ||
+	    (table->revision == 5 && fadt->minor_revision >= 1)) {
+		/*
+		 * ACPI 5.1 only has two explicit methods to boot up SMP,
+		 * PSCI and Parking protocol, but the Parking protocol is
+		 * only specified for ARMv7 now, so make PSCI as the only
+		 * way for the SMP boot protocol before some updates for
+		 * the ACPI spec or the Parking protocol spec.
+		 */
+		if (acpi_psci_present())
+			return 0;
+
+		pr_warn("No PSCI support, will not bring up secondary CPUs\n");
+		return -EOPNOTSUPP;
+	}
+
+	pr_warn("Unsupported FADT revision %d.%d, should be 5.1+, will disable ACPI\n",
+		table->revision, fadt->minor_revision);
+	disable_acpi();
+
+	return -EINVAL;
+}
+
+/*
+ * acpi_boot_table_init() called from setup_arch(), always.
+ *	1. find RSDP and get its address, and then find XSDT
+ *	2. extract all tables and checksums them all
+ *	3. check ACPI FADT revision
+ *
+ * We can parse ACPI boot-time tables such as MADT after
+ * this function is called.
+ */
+void __init acpi_boot_table_init(void)
+{
+	/* If acpi_disabled, bail out */
+	if (acpi_disabled)
+		return;
+
+	/* Initialize the ACPI boot-time table parser. */
+	if (acpi_table_init()) {
+		disable_acpi();
+		return;
+	}
+
+	if (acpi_table_parse(ACPI_SIG_FADT, acpi_parse_fadt))
+		pr_err("Can't find FADT or error happened during parsing FADT\n");
+}
+
+void __init acpi_gic_init(void)
+{
+	struct acpi_table_header *table;
+	acpi_status status;
+	acpi_size tbl_size;
+	int err;
+
+	if (acpi_disabled)
+		return;
+
+	status = acpi_get_table_with_size(ACPI_SIG_MADT, 0, &table, &tbl_size);
+	if (ACPI_FAILURE(status)) {
+		const char *msg = acpi_format_exception(status);
+
+		pr_err("Failed to get MADT table, %s\n", msg);
+		return;
+	}
+
+	err = gic_v2_acpi_init(table);
+	if (err)
+		pr_err("Failed to initialize GIC IRQ controller");
+
+	early_acpi_os_unmap_memory((char *)table, tbl_size);
+}
+
+static int __init parse_acpi(char *arg)
+{
+	if (!arg)
+		return -EINVAL;
+
+	/* "acpi=off" disables both ACPI table parsing and interpreter */
+	if (strcmp(arg, "off") == 0)
+		disable_acpi();
+	else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */
+		enable_acpi();
+	else
+		return -EINVAL;	/* Core will print when we return error */
+
+	return 0;
+}
+early_param("acpi", parse_acpi);
-- 
2.1.0