1 files changed, 345 insertions, 0 deletions
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
new file mode 100644
index 000000000000..8b839558838e
--- /dev/null
+++ b/arch/arm64/kernel/acpi.c
@@ -0,0 +1,345 @@
+/*
+ *  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);
+}