/*
* 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;
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
* @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 __init acpi_map_gic_cpu_interface(u64 mpidr, u8 enabled)
{
int i;
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;
}
/* 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 -EINVAL;
}
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 -EINVAL;
}
}
if (!acpi_psci_present())
return -EOPNOTSUPP;
cpu_ops[enabled_cpus] = cpu_get_ops("psci");
/* CPU 0 was already initialized */
if (enabled_cpus) {
if (!cpu_ops[enabled_cpus])
return -EINVAL;
if (cpu_ops[enabled_cpus]->cpu_init(NULL, enabled_cpus))
return -EOPNOTSUPP;
/* map the logical cpu id to cpu MPIDR */
cpu_logical_map(enabled_cpus) = mpidr;
}
enabled_cpus++;
return 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->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_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);
}
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 GIC and SMP
* boot protocol configuration data, or we will disable ACPI.
*/
if (table->revision > 5 ||
(table->revision == 5 && fadt->minor_revision >= 1)) {
if (!acpi_gbl_reduced_hardware) {
pr_err("Not hardware reduced ACPI mode, will not be supported\n");
goto disable_acpi;
}
/*
* 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 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:
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)
{
/*
* 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;
enable_acpi();
/* Initialize the ACPI boot-time table parser. */
if (acpi_table_init()) {
disable_acpi();
return;
}
if (acpi_table_parse(ACPI_SIG_FADT, acpi_parse_fadt)) {
/* disable ACPI if no FADT is found */
disable_acpi();
pr_err("Can't find 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);
}
