arch/arm64/kernel/acpi.c - kernel/lockdown - Git at Google

 /*
  *  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/acpi.h>
 #include <linux/bootmem.h>
 #include <linux/cpumask.h>
 #include <linux/init.h>
 #include <linux/irq.h>
 #include <linux/irqdomain.h>
 #include <linux/memblock.h>
 #include <linux/of_fdt.h>
 #include <linux/smp.h>

 #include <asm/cputype.h>
 #include <asm/cpu_ops.h>
 #include <asm/smp_plat.h>

 int acpi_noirq = 1;		/* skip ACPI IRQ initialization */
 int acpi_disabled = 1;
 EXPORT_SYMBOL(acpi_disabled);

 int acpi_pci_disabled = 1;	/* skip ACPI PCI scan and IRQ initialization */
 EXPORT_SYMBOL(acpi_pci_disabled);

 /* Processors with enabled flag and sane MPIDR */
 static int enabled_cpus;

 /* Boot CPU is valid or not in MADT */
 static bool bootcpu_valid  __initdata;

 static bool param_acpi_off __initdata;
 static bool param_acpi_force __initdata;

 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)
 		param_acpi_off = true;
 	else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */
 		param_acpi_force = true;
 	else
 		return -EINVAL;	/* Core will print when we return error */

 	return 0;
 }
 early_param("acpi", parse_acpi);

 static int __init dt_scan_depth1_nodes(unsigned long node,
 				       const char *uname, int depth,
 				       void *data)
 {
 	/*
 	 * Return 1 as soon as we encounter a node at depth 1 that is
 	 * not the /chosen node.
 	 */
 	if (depth == 1 && (strcmp(uname, "chosen") != 0))
 		return 1;
 	return 0;
 }

 /*
  * __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 (!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
  */
 static void __init
 acpi_map_gic_cpu_interface(struct acpi_madt_generic_interrupt *processor)
 {
 	int i;
 	u64 mpidr = processor->arm_mpidr & MPIDR_HWID_BITMASK;
 	bool enabled = !!(processor->flags & ACPI_MADT_ENABLED);

 	if (mpidr == INVALID_HWID) {
 		pr_info("Skip MADT cpu entry with invalid MPIDR\n");
 		return;
 	}

 	total_cpus++;
 	if (!enabled)
 		return;

 	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;
 	}

 	/* Check if GICC structure of boot CPU is available in the MADT */
 	if (cpu_logical_map(0) == mpidr) {
 		if (bootcpu_valid) {
 			pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
 			       mpidr);
 			return;
 		}

 		bootcpu_valid = true;
 	}

 	/*
 	 * Duplicate MPIDRs are a recipe for disaster. Scan
 	 * all initialized entries and check for
 	 * duplicates. If any is found just ignore the CPU.
 	 */
 	for (i = 1; i < enabled_cpus; i++) {
 		if (cpu_logical_map(i) == mpidr) {
 			pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
 			       mpidr);
 			return;
 		}
 	}

 	if (!acpi_psci_present())
 		return;

 	cpu_ops[enabled_cpus] = cpu_get_ops("psci");
 	/* CPU 0 was already initialized */
 	if (enabled_cpus) {
 		if (!cpu_ops[enabled_cpus])
 			return;

 		if (cpu_ops[enabled_cpus]->cpu_init(NULL, enabled_cpus))
 			return;

 		/* map the logical cpu id to cpu MPIDR */
 		cpu_logical_map(enabled_cpus) = mpidr;
 	}

 	enabled_cpus++;
 }

 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);
 	return 0;
 }

 /* Parse GIC cpu interface entries in MADT for SMP init */
 void __init acpi_init_cpus(void)
 {
 	int count, i;

 	/*
 	 * 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;
 	}

 	if (!bootcpu_valid) {
 		pr_err("MADT missing boot CPU MPIDR, not enabling secondaries\n");
 		return;
 	}

 	for (i = 0; i < enabled_cpus; i++)
 		set_cpu_possible(i, true);

 	/* Make boot-up look pretty */
 	pr_info("%d CPUs enabled, %d CPUs total\n", enabled_cpus, total_cpus);
 }

 /*
  * acpi_fadt_sanity_check() - Check FADT presence and carry out sanity
  *			      checks on it
  *
  * Return 0 on success,  <0 on failure
  */
 static int __init acpi_fadt_sanity_check(void)
 {
 	struct acpi_table_header *table;
 	struct acpi_table_fadt *fadt;
 	acpi_status status;
 	acpi_size tbl_size;
 	int ret = 0;

 	/*
 	 * FADT is required on arm64; retrieve it to check its presence
 	 * and carry out revision and ACPI HW reduced compliancy tests
 	 */
 	status = acpi_get_table_with_size(ACPI_SIG_FADT, 0, &table, &tbl_size);
 	if (ACPI_FAILURE(status)) {
 		const char *msg = acpi_format_exception(status);

 		pr_err("Failed to get FADT table, %s\n", msg);
 		return -ENODEV;
 	}

 	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 GIC and SMP
 	 * boot protocol configuration data.
 	 */
 	if (table->revision < 5 ||
 	   (table->revision == 5 && fadt->minor_revision < 1)) {
 		pr_err("Unsupported FADT revision %d.%d, should be 5.1+\n",
 		       table->revision, fadt->minor_revision);
 		ret = -EINVAL;
 		goto out;
 	}

 	if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) {
 		pr_err("FADT not ACPI hardware reduced compliant\n");
 		ret = -EINVAL;
 	}

 out:
 	/*
 	 * acpi_get_table_with_size() creates FADT table mapping that
 	 * should be released after parsing and before resuming boot
 	 */
 	early_acpi_os_unmap_memory(table, tbl_size);
 	return ret;
 }

 /*
  * 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
  *	4. check ACPI FADT HW reduced flag
  *
  * We can parse ACPI boot-time tables such as MADT after
  * this function is called.
  *
  * On return ACPI is enabled if either:
  *
  * - ACPI tables are initialized and sanity checks passed
  * - acpi=force was passed in the command line and ACPI was not disabled
  *   explicitly through acpi=off command line parameter
  *
  * ACPI is disabled on function return otherwise
  */
 void __init acpi_boot_table_init(void)
 {
 	/*
 	 * Enable ACPI instead of device tree unless
 	 * - ACPI has been disabled explicitly (acpi=off), or
 	 * - the device tree is not empty (it has more than just a /chosen node)
 	 *   and ACPI has not been force enabled (acpi=force)
 	 */
 	if (param_acpi_off ||
 	    (!param_acpi_force && of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
 		return;

 	/*
 	 * ACPI is disabled at this point. Enable it in order to parse
 	 * the ACPI tables and carry out sanity checks
 	 */
 	enable_acpi();

 	/*
 	 * If ACPI tables are initialized and FADT sanity checks passed,
 	 * leave ACPI enabled and carry on booting; otherwise disable ACPI
 	 * on initialization error.
 	 * If acpi=force was passed on the command line it forces ACPI
 	 * to be enabled even if its initialization failed.
 	 */
 	if (acpi_table_init() || acpi_fadt_sanity_check()) {
 		pr_err("Failed to init ACPI tables\n");
 		if (!param_acpi_force)
 			disable_acpi();
 	}
 }

 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);
 }
	/*
	* 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/acpi.h>
	#include <linux/bootmem.h>
	#include <linux/cpumask.h>
	#include <linux/init.h>
	#include <linux/irq.h>
	#include <linux/irqdomain.h>
	#include <linux/memblock.h>
	#include <linux/of_fdt.h>
	#include <linux/smp.h>

	#include <asm/cputype.h>
	#include <asm/cpu_ops.h>
	#include <asm/smp_plat.h>

	int acpi_noirq = 1; /* skip ACPI IRQ initialization */
	int acpi_disabled = 1;
	EXPORT_SYMBOL(acpi_disabled);

	int acpi_pci_disabled = 1; /* skip ACPI PCI scan and IRQ initialization */
	EXPORT_SYMBOL(acpi_pci_disabled);

	/* Processors with enabled flag and sane MPIDR */
	static int enabled_cpus;

	/* Boot CPU is valid or not in MADT */
	static bool bootcpu_valid __initdata;

	static bool param_acpi_off __initdata;
	static bool param_acpi_force __initdata;

	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)
	param_acpi_off = true;
	else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */
	param_acpi_force = true;
	else
	return -EINVAL; /* Core will print when we return error */

	return 0;
	}
	early_param("acpi", parse_acpi);

	static int __init dt_scan_depth1_nodes(unsigned long node,
	const char *uname, int depth,
	void *data)
	{
	/*
	* Return 1 as soon as we encounter a node at depth 1 that is
	* not the /chosen node.
	*/
	if (depth == 1 && (strcmp(uname, "chosen") != 0))
	return 1;
	return 0;
	}

	/*
	* __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 (!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
	*/
	static void __init
	acpi_map_gic_cpu_interface(struct acpi_madt_generic_interrupt *processor)
	{
	int i;
	u64 mpidr = processor->arm_mpidr & MPIDR_HWID_BITMASK;
	bool enabled = !!(processor->flags & ACPI_MADT_ENABLED);

	if (mpidr == INVALID_HWID) {
	pr_info("Skip MADT cpu entry with invalid MPIDR\n");
	return;
	}

	total_cpus++;
	if (!enabled)
	return;

	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;
	}

	/* Check if GICC structure of boot CPU is available in the MADT */
	if (cpu_logical_map(0) == mpidr) {
	if (bootcpu_valid) {
	pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
	mpidr);
	return;
	}

	bootcpu_valid = true;
	}

	/*
	* Duplicate MPIDRs are a recipe for disaster. Scan
	* all initialized entries and check for
	* duplicates. If any is found just ignore the CPU.
	*/
	for (i = 1; i < enabled_cpus; i++) {
	if (cpu_logical_map(i) == mpidr) {
	pr_err("Firmware bug, duplicate CPU MPIDR: 0x%llx in MADT\n",
	mpidr);
	return;
	}
	}

	if (!acpi_psci_present())
	return;

	cpu_ops[enabled_cpus] = cpu_get_ops("psci");
	/* CPU 0 was already initialized */
	if (enabled_cpus) {
	if (!cpu_ops[enabled_cpus])
	return;

	if (cpu_ops[enabled_cpus]->cpu_init(NULL, enabled_cpus))
	return;

	/* map the logical cpu id to cpu MPIDR */
	cpu_logical_map(enabled_cpus) = mpidr;
	}

	enabled_cpus++;
	}

	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);
	return 0;
	}

	/* Parse GIC cpu interface entries in MADT for SMP init */
	void __init acpi_init_cpus(void)
	{
	int count, i;

	/*
	* 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;
	}

	if (!bootcpu_valid) {
	pr_err("MADT missing boot CPU MPIDR, not enabling secondaries\n");
	return;
	}

	for (i = 0; i < enabled_cpus; i++)
	set_cpu_possible(i, true);

	/* Make boot-up look pretty */
	pr_info("%d CPUs enabled, %d CPUs total\n", enabled_cpus, total_cpus);
	}

	/*
	* acpi_fadt_sanity_check() - Check FADT presence and carry out sanity
	* checks on it
	*
	* Return 0 on success, <0 on failure
	*/
	static int __init acpi_fadt_sanity_check(void)
	{
	struct acpi_table_header *table;
	struct acpi_table_fadt *fadt;
	acpi_status status;
	acpi_size tbl_size;
	int ret = 0;

	/*
	* FADT is required on arm64; retrieve it to check its presence
	* and carry out revision and ACPI HW reduced compliancy tests
	*/
	status = acpi_get_table_with_size(ACPI_SIG_FADT, 0, &table, &tbl_size);
	if (ACPI_FAILURE(status)) {
	const char *msg = acpi_format_exception(status);

	pr_err("Failed to get FADT table, %s\n", msg);
	return -ENODEV;
	}

	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 GIC and SMP
	* boot protocol configuration data.
	*/
	if (table->revision < 5 \|\|
	(table->revision == 5 && fadt->minor_revision < 1)) {
	pr_err("Unsupported FADT revision %d.%d, should be 5.1+\n",
	table->revision, fadt->minor_revision);
	ret = -EINVAL;
	goto out;
	}

	if (!(fadt->flags & ACPI_FADT_HW_REDUCED)) {
	pr_err("FADT not ACPI hardware reduced compliant\n");
	ret = -EINVAL;
	}

	out:
	/*
	* acpi_get_table_with_size() creates FADT table mapping that
	* should be released after parsing and before resuming boot
	*/
	early_acpi_os_unmap_memory(table, tbl_size);
	return ret;
	}

	/*
	* 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
	* 4. check ACPI FADT HW reduced flag
	*
	* We can parse ACPI boot-time tables such as MADT after
	* this function is called.
	*
	* On return ACPI is enabled if either:
	*
	* - ACPI tables are initialized and sanity checks passed
	* - acpi=force was passed in the command line and ACPI was not disabled
	* explicitly through acpi=off command line parameter
	*
	* ACPI is disabled on function return otherwise
	*/
	void __init acpi_boot_table_init(void)
	{
	/*
	* Enable ACPI instead of device tree unless
	* - ACPI has been disabled explicitly (acpi=off), or
	* - the device tree is not empty (it has more than just a /chosen node)
	* and ACPI has not been force enabled (acpi=force)
	*/
	if (param_acpi_off \|\|
	(!param_acpi_force && of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
	return;

	/*
	* ACPI is disabled at this point. Enable it in order to parse
	* the ACPI tables and carry out sanity checks
	*/
	enable_acpi();

	/*
	* If ACPI tables are initialized and FADT sanity checks passed,
	* leave ACPI enabled and carry on booting; otherwise disable ACPI
	* on initialization error.
	* If acpi=force was passed on the command line it forces ACPI
	* to be enabled even if its initialization failed.
	*/
	if (acpi_table_init() \|\| acpi_fadt_sanity_check()) {
	pr_err("Failed to init ACPI tables\n");
	if (!param_acpi_force)
	disable_acpi();
	}
	}

	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);
	}