diff options
Diffstat (limited to 'arch/arm64/kernel/acpi.c')
| -rw-r--r-- | arch/arm64/kernel/acpi.c | 149 |
1 files changed, 147 insertions, 2 deletions
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index 2269e3032c07..c9203c0a1179 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -25,6 +25,10 @@ #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); @@ -32,6 +36,12 @@ 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; @@ -85,6 +95,129 @@ void __init __acpi_unmap_table(char *map, unsigned long size) 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; @@ -96,8 +229,20 @@ static int __init acpi_parse_fadt(struct acpi_table_header *table) * boot protocol configuration data, or we will disable ACPI. */ if (table->revision > 5 || - (table->revision == 5 && fadt->minor_revision >= 1)) - return 0; + (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 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); |