diff options
| -rw-r--r-- | arch/arm64/Kconfig | 9 | ||||
| -rw-r--r-- | arch/arm64/include/asm/acpi.h | 19 | ||||
| -rw-r--r-- | arch/arm64/include/asm/hardirq.h | 2 | ||||
| -rw-r--r-- | arch/arm64/include/asm/smp.h | 9 | ||||
| -rw-r--r-- | arch/arm64/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/arm64/kernel/acpi_parking_protocol.c | 153 | ||||
| -rw-r--r-- | arch/arm64/kernel/cpu_ops.c | 27 | ||||
| -rw-r--r-- | arch/arm64/kernel/smp.c | 28 |
8 files changed, 242 insertions, 6 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 8cc62289a63e..53e48a617fef 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -756,6 +756,15 @@ endmenu menu "Boot options" +config ARM64_ACPI_PARKING_PROTOCOL + bool "Enable support for the ARM64 ACPI parking protocol" + depends on ACPI + help + Enable support for the ARM64 ACPI parking protocol. If disabled + the kernel will not allow booting through the ARM64 ACPI parking + protocol even if the corresponding data is present in the ACPI + MADT table. + config CMDLINE string "Default kernel command string" default "" diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index caafd63b8092..aee323b13802 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -87,9 +87,26 @@ void __init acpi_init_cpus(void); static inline void acpi_init_cpus(void) { } #endif /* CONFIG_ACPI */ +#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL +bool acpi_parking_protocol_valid(int cpu); +void __init +acpi_set_mailbox_entry(int cpu, struct acpi_madt_generic_interrupt *processor); +#else +static inline bool acpi_parking_protocol_valid(int cpu) { return false; } +static inline void +acpi_set_mailbox_entry(int cpu, struct acpi_madt_generic_interrupt *processor) +{} +#endif + static inline const char *acpi_get_enable_method(int cpu) { - return acpi_psci_present() ? "psci" : NULL; + if (acpi_psci_present()) + return "psci"; + + if (acpi_parking_protocol_valid(cpu)) + return "parking-protocol"; + + return NULL; } #ifdef CONFIG_ACPI_APEI diff --git a/arch/arm64/include/asm/hardirq.h b/arch/arm64/include/asm/hardirq.h index a57601f9d17c..8740297dac77 100644 --- a/arch/arm64/include/asm/hardirq.h +++ b/arch/arm64/include/asm/hardirq.h @@ -20,7 +20,7 @@ #include <linux/threads.h> #include <asm/irq.h> -#define NR_IPI 5 +#define NR_IPI 6 typedef struct { unsigned int __softirq_pending; diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h index d9c3d6a6100a..2013a4dc5124 100644 --- a/arch/arm64/include/asm/smp.h +++ b/arch/arm64/include/asm/smp.h @@ -64,6 +64,15 @@ extern void secondary_entry(void); extern void arch_send_call_function_single_ipi(int cpu); extern void arch_send_call_function_ipi_mask(const struct cpumask *mask); +#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL +extern void arch_send_wakeup_ipi_mask(const struct cpumask *mask); +#else +static inline void arch_send_wakeup_ipi_mask(const struct cpumask *mask) +{ + BUILD_BUG(); +} +#endif + extern int __cpu_disable(void); extern void __cpu_die(unsigned int cpu); diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 83cd7e68e83b..8a9c65ccb636 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -41,6 +41,7 @@ arm64-obj-$(CONFIG_EFI) += efi.o efi-entry.stub.o arm64-obj-$(CONFIG_PCI) += pci.o arm64-obj-$(CONFIG_ARMV8_DEPRECATED) += armv8_deprecated.o arm64-obj-$(CONFIG_ACPI) += acpi.o +arm64-obj-$(CONFIG_ARM64_ACPI_PARKING_PROTOCOL) += acpi_parking_protocol.o arm64-obj-$(CONFIG_PARAVIRT) += paravirt.o obj-y += $(arm64-obj-y) vdso/ diff --git a/arch/arm64/kernel/acpi_parking_protocol.c b/arch/arm64/kernel/acpi_parking_protocol.c new file mode 100644 index 000000000000..4b1e5a7a98da --- /dev/null +++ b/arch/arm64/kernel/acpi_parking_protocol.c @@ -0,0 +1,153 @@ +/* + * ARM64 ACPI Parking Protocol implementation + * + * Authors: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> + * Mark Salter <msalter@redhat.com> + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#include <linux/acpi.h> +#include <linux/types.h> + +#include <asm/cpu_ops.h> + +struct cpu_mailbox_entry { + phys_addr_t mailbox_addr; + u8 version; + u8 gic_cpu_id; +}; + +static struct cpu_mailbox_entry cpu_mailbox_entries[NR_CPUS]; + +void __init acpi_set_mailbox_entry(int cpu, + struct acpi_madt_generic_interrupt *p) +{ + struct cpu_mailbox_entry *cpu_entry = &cpu_mailbox_entries[cpu]; + + cpu_entry->mailbox_addr = p->parked_address; + cpu_entry->version = p->parking_version; + cpu_entry->gic_cpu_id = p->cpu_interface_number; +} + +bool acpi_parking_protocol_valid(int cpu) +{ + struct cpu_mailbox_entry *cpu_entry = &cpu_mailbox_entries[cpu]; + + return cpu_entry->mailbox_addr && cpu_entry->version; +} + +static int acpi_parking_protocol_cpu_init(unsigned int cpu) +{ + pr_debug("%s: ACPI parked addr=%llx\n", __func__, + cpu_mailbox_entries[cpu].mailbox_addr); + + return 0; +} + +static int acpi_parking_protocol_cpu_prepare(unsigned int cpu) +{ + return 0; +} + +struct parking_protocol_mailbox { + __le32 cpu_id; + __le32 reserved; + __le64 entry_point; +}; + +static int acpi_parking_protocol_cpu_boot(unsigned int cpu) +{ + struct cpu_mailbox_entry *cpu_entry = &cpu_mailbox_entries[cpu]; + struct parking_protocol_mailbox __iomem *mailbox; + __le32 cpu_id; + + /* + * Map mailbox memory with attribute device nGnRE (ie ioremap - + * this deviates from the parking protocol specifications since + * the mailboxes are required to be mapped nGnRnE; the attribute + * discrepancy is harmless insofar as the protocol specification + * is concerned). + * If the mailbox is mistakenly allocated in the linear mapping + * by FW ioremap will fail since the mapping will be prevented + * by the kernel (it clashes with the linear mapping attributes + * specifications). + */ + mailbox = ioremap(cpu_entry->mailbox_addr, sizeof(*mailbox)); + if (!mailbox) + return -EIO; + + cpu_id = readl_relaxed(&mailbox->cpu_id); + /* + * Check if firmware has set-up the mailbox entry properly + * before kickstarting the respective cpu. + */ + if (cpu_id != ~0U) { + iounmap(mailbox); + return -ENXIO; + } + + /* + * We write the entry point and cpu id as LE regardless of the + * native endianness of the kernel. Therefore, any boot-loaders + * that read this address need to convert this address to the + * Boot-Loader's endianness before jumping. + */ + writeq_relaxed(__pa(secondary_entry), &mailbox->entry_point); + writel_relaxed(cpu_entry->gic_cpu_id, &mailbox->cpu_id); + + arch_send_wakeup_ipi_mask(cpumask_of(cpu)); + + iounmap(mailbox); + + return 0; +} + +static void acpi_parking_protocol_cpu_postboot(void) +{ + int cpu = smp_processor_id(); + struct cpu_mailbox_entry *cpu_entry = &cpu_mailbox_entries[cpu]; + struct parking_protocol_mailbox __iomem *mailbox; + __le64 entry_point; + + /* + * Map mailbox memory with attribute device nGnRE (ie ioremap - + * this deviates from the parking protocol specifications since + * the mailboxes are required to be mapped nGnRnE; the attribute + * discrepancy is harmless insofar as the protocol specification + * is concerned). + * If the mailbox is mistakenly allocated in the linear mapping + * by FW ioremap will fail since the mapping will be prevented + * by the kernel (it clashes with the linear mapping attributes + * specifications). + */ + mailbox = ioremap(cpu_entry->mailbox_addr, sizeof(*mailbox)); + if (!mailbox) + return; + + entry_point = readl_relaxed(&mailbox->entry_point); + /* + * Check if firmware has cleared the entry_point as expected + * by the protocol specification. + */ + WARN_ON(entry_point); + + iounmap(mailbox); +} + +const struct cpu_operations acpi_parking_protocol_ops = { + .name = "parking-protocol", + .cpu_init = acpi_parking_protocol_cpu_init, + .cpu_prepare = acpi_parking_protocol_cpu_prepare, + .cpu_boot = acpi_parking_protocol_cpu_boot, + .cpu_postboot = acpi_parking_protocol_cpu_postboot +}; diff --git a/arch/arm64/kernel/cpu_ops.c b/arch/arm64/kernel/cpu_ops.c index b6bd7d447768..c7cfb8fe06f9 100644 --- a/arch/arm64/kernel/cpu_ops.c +++ b/arch/arm64/kernel/cpu_ops.c @@ -25,19 +25,30 @@ #include <asm/smp_plat.h> extern const struct cpu_operations smp_spin_table_ops; +extern const struct cpu_operations acpi_parking_protocol_ops; extern const struct cpu_operations cpu_psci_ops; const struct cpu_operations *cpu_ops[NR_CPUS]; -static const struct cpu_operations *supported_cpu_ops[] __initconst = { +static const struct cpu_operations *dt_supported_cpu_ops[] __initconst = { &smp_spin_table_ops, &cpu_psci_ops, NULL, }; +static const struct cpu_operations *acpi_supported_cpu_ops[] __initconst = { +#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL + &acpi_parking_protocol_ops, +#endif + &cpu_psci_ops, + NULL, +}; + static const struct cpu_operations * __init cpu_get_ops(const char *name) { - const struct cpu_operations **ops = supported_cpu_ops; + const struct cpu_operations **ops; + + ops = acpi_disabled ? dt_supported_cpu_ops : acpi_supported_cpu_ops; while (*ops) { if (!strcmp(name, (*ops)->name)) @@ -75,8 +86,16 @@ static const char *__init cpu_read_enable_method(int cpu) } } else { enable_method = acpi_get_enable_method(cpu); - if (!enable_method) - pr_err("Unsupported ACPI enable-method\n"); + if (!enable_method) { + /* + * In ACPI systems the boot CPU does not require + * checking the enable method since for some + * boot protocol (ie parking protocol) it need not + * be initialized. Don't warn spuriously. + */ + if (cpu != 0) + pr_err("Unsupported ACPI enable-method\n"); + } } return enable_method; diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 68e7f79630d4..24cb4f800033 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -70,6 +70,7 @@ enum ipi_msg_type { IPI_CPU_STOP, IPI_TIMER, IPI_IRQ_WORK, + IPI_WAKEUP }; /* @@ -443,6 +444,17 @@ acpi_map_gic_cpu_interface(struct acpi_madt_generic_interrupt *processor) /* map the logical cpu id to cpu MPIDR */ cpu_logical_map(cpu_count) = hwid; + /* + * Set-up the ACPI parking protocol cpu entries + * while initializing the cpu_logical_map to + * avoid parsing MADT entries multiple times for + * nothing (ie a valid cpu_logical_map entry should + * contain a valid parking protocol data set to + * initialize the cpu if the parking protocol is + * the only available enable method). + */ + acpi_set_mailbox_entry(cpu_count, processor); + cpu_count++; } @@ -625,6 +637,7 @@ static const char *ipi_types[NR_IPI] __tracepoint_string = { S(IPI_CPU_STOP, "CPU stop interrupts"), S(IPI_TIMER, "Timer broadcast interrupts"), S(IPI_IRQ_WORK, "IRQ work interrupts"), + S(IPI_WAKEUP, "CPU wake-up interrupts"), }; static void smp_cross_call(const struct cpumask *target, unsigned int ipinr) @@ -668,6 +681,13 @@ void arch_send_call_function_single_ipi(int cpu) smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC); } +#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL +void arch_send_wakeup_ipi_mask(const struct cpumask *mask) +{ + smp_cross_call(mask, IPI_WAKEUP); +} +#endif + #ifdef CONFIG_IRQ_WORK void arch_irq_work_raise(void) { @@ -745,6 +765,14 @@ void handle_IPI(int ipinr, struct pt_regs *regs) break; #endif +#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL + case IPI_WAKEUP: + WARN_ONCE(!acpi_parking_protocol_valid(cpu), + "CPU%u: Wake-up IPI outside the ACPI parking protocol\n", + cpu); + break; +#endif + default: pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr); break; |