/*
* This is the secondary CPU boot entry. We're using this CPUs
* idle thread stack, but a set of temporary page tables.
*/
asmlinkage void secondary_start_kernel(void)
{
struct mm_struct *mm = &init_mm;
unsigned int cpu = smp_processor_id();
/*
* All kernel threads share the same mm context; grab a
* reference and switch to it.
*/
atomic_inc(&mm->mm_count);
current->active_mm = mm;
cpumask_set_cpu(cpu, mm_cpumask(mm));
set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
printk("CPU%u: Booted secondary processor\n", cpu);
/*
* TTBR0 is only used for the identity mapping at this stage. Make it
* point to zero page to avoid speculatively fetching new entries.
*/
cpu_set_reserved_ttbr0();
flush_tlb_all();
cpu_set_default_tcr_t0sz();
preempt_disable();
trace_hardirqs_off();
if (cpu_ops[cpu]->cpu_postboot)
cpu_ops[cpu]->cpu_postboot();
/*
* Log the CPU info before it is marked online and might get read.
*/
cpuinfo_store_cpu();
/*
* Enable GIC and timers.
*/
notify_cpu_starting(cpu);
smp_store_cpu_info(cpu);
/*
* OK, now it's safe to let the boot CPU continue. Wait for
* the CPU migration code to notice that the CPU is online
* before we continue.
*/
set_cpu_online(cpu, true);
complete(&cpu_running);
local_dbg_enable();
local_irq_enable();
local_async_enable();
/*
* OK, it's off to the idle thread for us
*/
cpu_startup_entry(CPUHP_ONLINE);
}
static void __init setup_machine_fdt(phys_addr_t dt_phys)
{
struct boot_param_header *devtree;
unsigned long dt_root;
cpuinfo_store_cpu();
/* Check we have a non-NULL DT pointer */
if (!dt_phys) {
early_print("\n"
"Error: NULL or invalid device tree blob\n"
"The dtb must be 8-byte aligned and passed in the first 512MB of memory\n"
"\nPlease check your bootloader.\n");
while (true)
cpu_relax();
}
devtree = phys_to_virt(dt_phys);
/* Check device tree validity */
if (be32_to_cpu(devtree->magic) != OF_DT_HEADER) {
early_print("\n"
"Error: invalid device tree blob at physical address 0x%p (virtual address 0x%p)\n"
"Expected 0x%x, found 0x%x\n"
"\nPlease check your bootloader.\n",
dt_phys, devtree, OF_DT_HEADER,
be32_to_cpu(devtree->magic));
while (true)
cpu_relax();
}
initial_boot_params = devtree;
dt_root = of_get_flat_dt_root();
machine_name = of_get_flat_dt_prop(dt_root, "model", NULL);
if (!machine_name)
machine_name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
if (!machine_name)
machine_name = "<unknown>";
pr_info("Machine: %s\n", machine_name);
/* Retrieve various information from the /chosen node */
of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
/* Initialize {size,address}-cells info */
of_scan_flat_dt(early_init_dt_scan_root, NULL);
/* Setup memory, calling early_init_dt_add_memory_arch */
of_scan_flat_dt(early_init_dt_scan_memory, NULL);
}
/*
* This is the secondary CPU boot entry. We're using this CPUs
* idle thread stack, but a set of temporary page tables.
*/
asmlinkage void secondary_start_kernel(void)
{
struct mm_struct *mm = &init_mm;
unsigned int cpu = smp_processor_id();
/*
* All kernel threads share the same mm context; grab a
* reference and switch to it.
*/
atomic_inc(&mm->mm_count);
current->active_mm = mm;
set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
/*
* TTBR0 is only used for the identity mapping at this stage. Make it
* point to zero page to avoid speculatively fetching new entries.
*/
cpu_uninstall_idmap();
preempt_disable();
trace_hardirqs_off();
/*
* If the system has established the capabilities, make sure
* this CPU ticks all of those. If it doesn't, the CPU will
* fail to come online.
*/
verify_local_cpu_capabilities();
if (cpu_ops[cpu]->cpu_postboot)
cpu_ops[cpu]->cpu_postboot();
/*
* Log the CPU info before it is marked online and might get read.
*/
cpuinfo_store_cpu();
/*
* Enable GIC and timers.
*/
notify_cpu_starting(cpu);
store_cpu_topology(cpu);
/*
* OK, now it's safe to let the boot CPU continue. Wait for
* the CPU migration code to notice that the CPU is online
* before we continue.
*/
pr_info("CPU%u: Booted secondary processor [%08x]\n",
cpu, read_cpuid_id());
update_cpu_boot_status(CPU_BOOT_SUCCESS);
set_cpu_online(cpu, true);
complete(&cpu_running);
local_irq_enable();
local_async_enable();
/*
* OK, it's off to the idle thread for us
*/
cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
}
