/**
* This is the architecture-independent kernel entry point. Before it is
* called, architecture-specific code has done the bare minimum initialization
* necessary. This function initializes the kernel and its various subsystems.
* It calls back to architecture-specific code at several well defined points,
* which all architectures must implement (e.g., setup_arch()).
*
* \callgraph
*/
void
start_kernel()
{
unsigned int cpu;
unsigned int timeout;
int status;
/*
* Parse the kernel boot command line.
* This is where boot-time configurable variables get set,
* e.g., the ones with param() and DRIVER_PARAM() specifiers.
*/
parse_params(lwk_command_line);
/*
* Initialize the console subsystem.
* printk()'s will be visible after this.
*/
console_init();
/*
* Hello, Dave.
*/
printk("%s", lwk_banner);
printk(KERN_DEBUG "%s\n", lwk_command_line);
sort_exception_table();
/*
* Do architecture specific initialization.
* This detects memory, CPUs, architecture dependent irqs, etc.
*/
setup_arch();
/*
* Setup the architecture independent interrupt handling.
*/
irq_init();
/*
* Initialize the kernel memory subsystem. Up until now, the simple
* boot-time memory allocator (bootmem) has been used for all dynamic
* memory allocation. Here, the bootmem allocator is destroyed and all
* of the free pages it was managing are added to the kernel memory
* pool (kmem) or the user memory pool (umem).
*
* After this point, any use of the bootmem allocator will cause a
* kernel panic. The normal kernel memory subsystem API should be used
* instead (e.g., kmem_alloc() and kmem_free()).
*/
mem_subsys_init();
/*
* Initialize the address space management subsystem.
*/
aspace_subsys_init();
sched_init_runqueue(0); /* This CPUs scheduler state + idle task */
sched_add_task(current); /* now safe to call schedule() */
/*
* Initialize the task scheduling subsystem.
*/
core_timer_init(0);
/* Start the kernel filesystems */
kfs_init();
/*
* Initialize the random number generator.
*/
rand_init();
workq_init();
/*
* Boot all of the other CPUs in the system, one at a time.
*/
printk(KERN_INFO "Number of CPUs detected: %d\n", num_cpus());
for_each_cpu_mask(cpu, cpu_present_map) {
/* The bootstrap CPU (that's us) is already booted. */
if (cpu == 0) {
cpu_set(cpu, cpu_online_map);
continue;
}
printk(KERN_DEBUG "Booting CPU %u.\n", cpu);
arch_boot_cpu(cpu);
/* Wait for ACK that CPU has booted (5 seconds max). */
for (timeout = 0; timeout < 50000; timeout++) {
if (cpu_isset(cpu, cpu_online_map))
break;
udelay(100);
}
if (!cpu_isset(cpu, cpu_online_map))
panic("Failed to boot CPU %d.\n", cpu);
}
/*
* Initialize the PCI subsystem.
*/
init_pci();
/*
* Enable external interrupts.
*/
local_irq_enable();
#ifdef CONFIG_NETWORK
/*
* Bring up any network devices.
*/
netdev_init();
#endif
#ifdef CONFIG_CRAY_GEMINI
driver_init_list("net", "gemini");
#endif
#ifdef CONFIG_BLOCK_DEVICE
/**
* Initialize the block devices
*/
blkdev_init();
#endif
mcheck_init_late();
/*
* And any modules that need to be started.
*/
driver_init_by_name( "module", "*" );
#ifdef CONFIG_KGDB
/*
* Stop eary (before "late" devices) in KGDB if requested
*/
kgdb_initial_breakpoint();
#endif
/*
* Bring up any late init devices.
*/
driver_init_by_name( "late", "*" );
/*
* Bring up the Linux compatibility layer, if enabled.
*/
linux_init();
#ifdef CONFIG_DEBUG_HW_NOISE
/* Measure noise/interference in the underlying hardware/VMM */
extern void measure_noise(int, uint64_t);
measure_noise(0, 0);
#endif
/*
* Start up user-space...
*/
printk(KERN_INFO "Loading initial user-level task (init_task)...\n");
if ((status = create_init_task()) != 0)
panic("Failed to create init_task (status=%d).", status);
current->state = TASK_EXITED;
schedule(); /* This should not return */
BUG();
}
/**
* This is the architecture-independent kernel entry point. Before it is
* called, architecture-specific code has done the bare minimum initialization
* necessary. This function initializes the kernel and its various subsystems.
* It calls back to architecture-specific code at several well defined points,
* which all architectures must implement (e.g., setup_arch()).
*/
void
start_kernel()
{
unsigned int cpu;
unsigned int timeout;
/*
* Parse the kernel boot command line.
* This is where boot-time configurable variables get set,
* e.g., the ones with param() and driver_param() specifiers.
*/
parse_params(lwk_command_line);
/*
* Initialize the console subsystem.
* printk()'s will be visible after this.
*/
console_init();
/*
* Hello, Dave.
*/
printk(lwk_banner);
printk(KERN_DEBUG "%s\n", lwk_command_line);
/*
* Do architecture specific initialization.
* This detects memory, CPUs, etc.
*/
setup_arch();
/*
* Initialize the kernel memory subsystem. Up until now, the simple
* boot-time memory allocator (bootmem) has been used for all dynamic
* memory allocation. Here, the bootmem allocator is destroyed and all
* of the free pages it was managing are added to the kernel memory
* pool (kmem) or the user memory pool (umem).
*
* After this point, any use of the bootmem allocator will cause a
* kernel panic. The normal kernel memory subsystem API should be used
* instead (e.g., kmem_alloc() and kmem_free()).
*/
mem_subsys_init();
/*
* Initialize the address space management subsystem.
*/
aspace_subsys_init();
/*
* Initialize the task management subsystem.
*/
task_subsys_init();
/*
* Initialize the task scheduling subsystem.
*/
sched_subsys_init();
/*
* Initialize the task scheduling subsystem.
*/
timer_subsys_init();
/*
* Boot all of the other CPUs in the system, one at a time.
*/
printk(KERN_INFO "Number of CPUs detected: %d\n", num_cpus());
for_each_cpu_mask(cpu, cpu_present_map) {
/* The bootstrap CPU (that's us) is already booted. */
if (cpu == 0) {
cpu_set(cpu, cpu_online_map);
continue;
}
printk(KERN_DEBUG "Booting CPU %u.\n", cpu);
arch_boot_cpu(cpu);
/* Wait for ACK that CPU has booted (5 seconds max). */
for (timeout = 0; timeout < 50000; timeout++) {
if (cpu_isset(cpu, cpu_online_map))
break;
udelay(100);
}
if (!cpu_isset(cpu, cpu_online_map))
panic("Failed to boot CPU %d.\n", cpu);
}
#ifdef CONFIG_V3VEE
v3vee_run_vmm();
printk( "%s: VMM returned. We're spinning\n", __func__ );
while(1) { asm( "hlt" ); }
#else
/*
* Start up user-space...
*/
printk(KERN_INFO "Loading initial user-level task (init_task)...\n");
int status;
if ((status = create_init_task()) != 0)
panic("Failed to create init_task (status=%d).", status);
schedule(); /* This should not return */
BUG();
#endif
}
