diff --git a/arch/arm64/include/asm/cpu_ops.h b/arch/arm64/include/asm/cpu_ops.h index 3c60c8d1d928aeeac2d19632b8cbe4c120ae9a43..67bc4fd83798c625993ca22bde489210fb98d83a 100644 --- a/arch/arm64/include/asm/cpu_ops.h +++ b/arch/arm64/include/asm/cpu_ops.h @@ -21,10 +21,26 @@ struct device_node; +/** + * struct cpu_operations - Callback operations for hotplugging CPUs. + * + * @name: Name of the property as appears in a devicetree cpu node's + * enable-method property. + * @cpu_init: Reads any data necessary for a specific enable-method from the + * devicetree, for a given cpu node and proposed logical id. + * @cpu_prepare: Early one-time preparation step for a cpu. If there is a + * mechanism for doing so, tests whether it is possible to boot + * the given CPU. + * @cpu_boot: Boots a cpu into the kernel. + * @cpu_postboot: Optionally, perform any post-boot cleanup or necesary + * synchronisation. Called from the cpu being booted. + */ struct cpu_operations { const char *name; int (*cpu_init)(struct device_node *, unsigned int); int (*cpu_prepare)(unsigned int); + int (*cpu_boot)(unsigned int); + void (*cpu_postboot)(void); }; extern const struct cpu_operations *cpu_ops[NR_CPUS]; diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h index 7e34295f78e325ac59dead45f440d20c1d4db319..d64187ce69a2459f1d15681b6c5dfebff05b335e 100644 --- a/arch/arm64/include/asm/smp.h +++ b/arch/arm64/include/asm/smp.h @@ -60,8 +60,7 @@ struct secondary_data { void *stack; }; extern struct secondary_data secondary_data; -extern void secondary_holding_pen(void); -extern volatile unsigned long secondary_holding_pen_release; +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); diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 7090c126797cb27e3db102e830d5de72c14c3310..bf7efdf2d7e79584af4645992dd010a47f365c21 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -225,7 +225,6 @@ ENTRY(__boot_cpu_mode) .quad PAGE_OFFSET #ifdef CONFIG_SMP - .pushsection .smp.pen.text, "ax" .align 3 1: .quad . .quad secondary_holding_pen_release @@ -250,7 +249,16 @@ pen: ldr x4, [x3] wfe b pen ENDPROC(secondary_holding_pen) - .popsection + + /* + * Secondary entry point that jumps straight into the kernel. Only to + * be used where CPUs are brought online dynamically by the kernel. + */ +ENTRY(secondary_entry) + bl __calc_phys_offset // x2=phys offset + bl el2_setup // Drop to EL1 + b secondary_startup +ENDPROC(secondary_entry) ENTRY(secondary_startup) /* diff --git a/arch/arm64/kernel/psci.c b/arch/arm64/kernel/psci.c index ccec2ca67755c2ba8f2ef39300ad318eba963491..fb56b6158344ab2c4db0bf01097126ce9026aef6 100644 --- a/arch/arm64/kernel/psci.c +++ b/arch/arm64/kernel/psci.c @@ -239,26 +239,28 @@ static int __init cpu_psci_cpu_init(struct device_node *dn, unsigned int cpu) static int __init cpu_psci_cpu_prepare(unsigned int cpu) { - int err; - if (!psci_ops.cpu_on) { pr_err("no cpu_on method, not booting CPU%d\n", cpu); return -ENODEV; } - err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_holding_pen)); - if (err) { - pr_err("failed to boot CPU%d (%d)\n", cpu, err); - return err; - } - return 0; } +static int cpu_psci_cpu_boot(unsigned int cpu) +{ + int err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_entry)); + if (err) + pr_err("psci: failed to boot CPU%d (%d)\n", cpu, err); + + return err; +} + const struct cpu_operations cpu_psci_ops = { .name = "psci", .cpu_init = cpu_psci_cpu_init, .cpu_prepare = cpu_psci_cpu_prepare, + .cpu_boot = cpu_psci_cpu_boot, }; #endif diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 8965fb7dee89bb94de7d42571cf699ed59449bd4..6806bc40b630ec2b104c8743bfeccf9a40a6f16e 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -55,7 +55,6 @@ * where to place its SVC stack */ struct secondary_data secondary_data; -volatile unsigned long secondary_holding_pen_release = INVALID_HWID; enum ipi_msg_type { IPI_RESCHEDULE, @@ -64,61 +63,16 @@ enum ipi_msg_type { IPI_CPU_STOP, }; -static DEFINE_RAW_SPINLOCK(boot_lock); - -/* - * Write secondary_holding_pen_release in a way that is guaranteed to be - * visible to all observers, irrespective of whether they're taking part - * in coherency or not. This is necessary for the hotplug code to work - * reliably. - */ -static void write_pen_release(u64 val) -{ - void *start = (void *)&secondary_holding_pen_release; - unsigned long size = sizeof(secondary_holding_pen_release); - - secondary_holding_pen_release = val; - __flush_dcache_area(start, size); -} - /* * Boot a secondary CPU, and assign it the specified idle task. * This also gives us the initial stack to use for this CPU. */ static int boot_secondary(unsigned int cpu, struct task_struct *idle) { - unsigned long timeout; - - /* - * Set synchronisation state between this boot processor - * and the secondary one - */ - raw_spin_lock(&boot_lock); - - /* - * Update the pen release flag. - */ - write_pen_release(cpu_logical_map(cpu)); + if (cpu_ops[cpu]->cpu_boot) + return cpu_ops[cpu]->cpu_boot(cpu); - /* - * Send an event, causing the secondaries to read pen_release. - */ - sev(); - - timeout = jiffies + (1 * HZ); - while (time_before(jiffies, timeout)) { - if (secondary_holding_pen_release == INVALID_HWID) - break; - udelay(10); - } - - /* - * Now the secondary core is starting up let it run its - * calibrations, then wait for it to finish - */ - raw_spin_unlock(&boot_lock); - - return secondary_holding_pen_release != INVALID_HWID ? -ENOSYS : 0; + return -EOPNOTSUPP; } static DECLARE_COMPLETION(cpu_running); @@ -188,17 +142,8 @@ asmlinkage void secondary_start_kernel(void) preempt_disable(); trace_hardirqs_off(); - /* - * Let the primary processor know we're out of the - * pen, then head off into the C entry point - */ - write_pen_release(INVALID_HWID); - - /* - * Synchronise with the boot thread. - */ - raw_spin_lock(&boot_lock); - raw_spin_unlock(&boot_lock); + if (cpu_ops[cpu]->cpu_postboot) + cpu_ops[cpu]->cpu_postboot(); /* * OK, now it's safe to let the boot CPU continue. Wait for diff --git a/arch/arm64/kernel/smp_spin_table.c b/arch/arm64/kernel/smp_spin_table.c index a8b76e4eccff1be8b59c90307b178b37c0d235da..27f08367a6e73ef9abfc8e313a927ae223514b92 100644 --- a/arch/arm64/kernel/smp_spin_table.c +++ b/arch/arm64/kernel/smp_spin_table.c @@ -16,14 +16,37 @@ * along with this program. If not, see . */ +#include #include #include #include #include #include +#include +#include + +extern void secondary_holding_pen(void); +volatile unsigned long secondary_holding_pen_release = INVALID_HWID; static phys_addr_t cpu_release_addr[NR_CPUS]; +static DEFINE_RAW_SPINLOCK(boot_lock); + +/* + * Write secondary_holding_pen_release in a way that is guaranteed to be + * visible to all observers, irrespective of whether they're taking part + * in coherency or not. This is necessary for the hotplug code to work + * reliably. + */ +static void write_pen_release(u64 val) +{ + void *start = (void *)&secondary_holding_pen_release; + unsigned long size = sizeof(secondary_holding_pen_release); + + secondary_holding_pen_release = val; + __flush_dcache_area(start, size); +} + static int smp_spin_table_cpu_init(struct device_node *dn, unsigned int cpu) { @@ -60,8 +83,60 @@ static int smp_spin_table_cpu_prepare(unsigned int cpu) return 0; } +static int smp_spin_table_cpu_boot(unsigned int cpu) +{ + unsigned long timeout; + + /* + * Set synchronisation state between this boot processor + * and the secondary one + */ + raw_spin_lock(&boot_lock); + + /* + * Update the pen release flag. + */ + write_pen_release(cpu_logical_map(cpu)); + + /* + * Send an event, causing the secondaries to read pen_release. + */ + sev(); + + timeout = jiffies + (1 * HZ); + while (time_before(jiffies, timeout)) { + if (secondary_holding_pen_release == INVALID_HWID) + break; + udelay(10); + } + + /* + * Now the secondary core is starting up let it run its + * calibrations, then wait for it to finish + */ + raw_spin_unlock(&boot_lock); + + return secondary_holding_pen_release != INVALID_HWID ? -ENOSYS : 0; +} + +void smp_spin_table_cpu_postboot(void) +{ + /* + * Let the primary processor know we're out of the pen. + */ + write_pen_release(INVALID_HWID); + + /* + * Synchronise with the boot thread. + */ + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); +} + const struct cpu_operations smp_spin_table_ops = { .name = "spin-table", .cpu_init = smp_spin_table_cpu_init, .cpu_prepare = smp_spin_table_cpu_prepare, + .cpu_boot = smp_spin_table_cpu_boot, + .cpu_postboot = smp_spin_table_cpu_postboot, }; diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index f8ab9d8e2ea3343a0b185d1c5d6cd306afa99fc2..991ffddf49dfa2df60695ab97d04d731a628858d 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -54,7 +54,6 @@ SECTIONS } .text : { /* Real text segment */ _stext = .; /* Text and read-only data */ - *(.smp.pen.text) __exception_text_start = .; *(.exception.text) __exception_text_end = .;