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minix/kernel/main.c
Thomas Cort 9f23acf410 kernel: spelling fixes 
Change-Id: I73c759bdef98be35be77130895ae0ec497e1b954
2013-10-09 20:24:17 -04:00

517 lines
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/* This file contains the main program of MINIX as well as its shutdown code.
* The routine main() initializes the system and starts the ball rolling by
* setting up the process table, interrupt vectors, and scheduling each task
* to run to initialize itself.
* The routine shutdown() does the opposite and brings down MINIX.
*
* The entries into this file are:
* main: MINIX main program
* prepare_shutdown: prepare to take MINIX down
*/
#include "kernel/kernel.h"
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <minix/com.h>
#include <minix/endpoint.h>
#include <machine/vmparam.h>
#include <minix/u64.h>
#include <minix/type.h>
#include <minix/reboot.h>
#include "clock.h"
#include "direct_utils.h"
#include "hw_intr.h"
#include "arch_proto.h"
#ifdef CONFIG_SMP
#include "smp.h"
#endif
#ifdef USE_WATCHDOG
#include "watchdog.h"
#endif
#include "spinlock.h"
/* dummy for linking */
char *** _penviron;
/* Prototype declarations for PRIVATE functions. */
static void announce(void);
void bsp_finish_booting(void)
{
int i;
#if SPROFILE
sprofiling = 0; /* we're not profiling until instructed to */
#endif /* SPROFILE */
cprof_procs_no = 0; /* init nr of hash table slots used */
cpu_identify();
vm_running = 0;
krandom.random_sources = RANDOM_SOURCES;
krandom.random_elements = RANDOM_ELEMENTS;
/* MINIX is now ready. All boot image processes are on the ready queue.
* Return to the assembly code to start running the current process.
*/
/* it should point somewhere */
get_cpulocal_var(bill_ptr) = get_cpulocal_var_ptr(idle_proc);
get_cpulocal_var(proc_ptr) = get_cpulocal_var_ptr(idle_proc);
announce(); /* print MINIX startup banner */
/*
* we have access to the cpu local run queue, only now schedule the processes.
* We ignore the slots for the former kernel tasks
*/
for (i=0; i < NR_BOOT_PROCS - NR_TASKS; i++) {
RTS_UNSET(proc_addr(i), RTS_PROC_STOP);
}
/*
* enable timer interrupts and clock task on the boot CPU
*/
if (boot_cpu_init_timer(system_hz)) {
panic("FATAL : failed to initialize timer interrupts, "
"cannot continue without any clock source!");
}
fpu_init();
/* Warnings for sanity checks that take time. These warnings are printed
* so it's a clear warning no full release should be done with them
* enabled.
*/
#if DEBUG_SCHED_CHECK
FIXME("DEBUG_SCHED_CHECK enabled");
#endif
#if DEBUG_VMASSERT
FIXME("DEBUG_VMASSERT enabled");
#endif
#if DEBUG_PROC_CHECK
FIXME("PROC check enabled");
#endif
DEBUGEXTRA(("cycles_accounting_init()... "));
cycles_accounting_init();
DEBUGEXTRA(("done\n"));
#ifdef CONFIG_SMP
cpu_set_flag(bsp_cpu_id, CPU_IS_READY);
machine.processors_count = ncpus;
machine.bsp_id = bsp_cpu_id;
#else
machine.processors_count = 1;
machine.bsp_id = 0;
#endif
/* Kernel may no longer use bits of memory as VM will be running soon */
kernel_may_alloc = 0;
switch_to_user();
NOT_REACHABLE;
}
#ifdef __arm__
#include "omap_serial.h"
#endif
/*===========================================================================*
* kmain *
*===========================================================================*/
void kmain(kinfo_t *local_cbi)
{
/* Start the ball rolling. */
struct boot_image *ip; /* boot image pointer */
register struct proc *rp; /* process pointer */
register int i, j;
/* save a global copy of the boot parameters */
memcpy(&kinfo, local_cbi, sizeof(kinfo));
memcpy(&kmess, kinfo.kmess, sizeof(kmess));
#ifdef __arm__
/* We want to initialize serial before we do any output */
omap3_ser_init();
#endif
/* We can talk now */
printf("MINIX booting\n");
/* Kernel may use bits of main memory before VM is started */
kernel_may_alloc = 1;
assert(sizeof(kinfo.boot_procs) == sizeof(image));
memcpy(kinfo.boot_procs, image, sizeof(kinfo.boot_procs));
cstart();
BKL_LOCK();
DEBUGEXTRA(("main()\n"));
proc_init();
if(NR_BOOT_MODULES != kinfo.mbi.mods_count)
panic("expecting %d boot processes/modules, found %d",
NR_BOOT_MODULES, kinfo.mbi.mods_count);
/* Set up proc table entries for processes in boot image. */
for (i=0; i < NR_BOOT_PROCS; ++i) {
int schedulable_proc;
proc_nr_t proc_nr;
int ipc_to_m, kcalls;
sys_map_t map;
ip = &image[i]; /* process' attributes */
DEBUGEXTRA(("initializing %s... ", ip->proc_name));
rp = proc_addr(ip->proc_nr); /* get process pointer */
ip->endpoint = rp->p_endpoint; /* ipc endpoint */
rp->p_cpu_time_left = 0;
if(i < NR_TASKS) /* name (tasks only) */
strlcpy(rp->p_name, ip->proc_name, sizeof(rp->p_name));
if(i >= NR_TASKS) {
/* Remember this so it can be passed to VM */
multiboot_module_t *mb_mod = &kinfo.module_list[i - NR_TASKS];
ip->start_addr = mb_mod->mod_start;
ip->len = mb_mod->mod_end - mb_mod->mod_start;
}
reset_proc_accounting(rp);
/* See if this process is immediately schedulable.
* In that case, set its privileges now and allow it to run.
* Only kernel tasks and the root system process get to run immediately.
* All the other system processes are inhibited from running by the
* RTS_NO_PRIV flag. They can only be scheduled once the root system
* process has set their privileges.
*/
proc_nr = proc_nr(rp);
schedulable_proc = (iskerneln(proc_nr) || isrootsysn(proc_nr) ||
proc_nr == VM_PROC_NR);
if(schedulable_proc) {
/* Assign privilege structure. Force a static privilege id. */
(void) get_priv(rp, static_priv_id(proc_nr));
/* Privileges for kernel tasks. */
if(proc_nr == VM_PROC_NR) {
priv(rp)->s_flags = VM_F;
priv(rp)->s_trap_mask = SRV_T;
ipc_to_m = SRV_M;
kcalls = SRV_KC;
priv(rp)->s_sig_mgr = SELF;
rp->p_priority = SRV_Q;
rp->p_quantum_size_ms = SRV_QT;
}
else if(iskerneln(proc_nr)) {
/* Privilege flags. */
priv(rp)->s_flags = (proc_nr == IDLE ? IDL_F : TSK_F);
/* Allowed traps. */
priv(rp)->s_trap_mask = (proc_nr == CLOCK
|| proc_nr == SYSTEM ? CSK_T : TSK_T);
ipc_to_m = TSK_M; /* allowed targets */
kcalls = TSK_KC; /* allowed kernel calls */
}
/* Privileges for the root system process. */
else {
assert(isrootsysn(proc_nr));
priv(rp)->s_flags= RSYS_F; /* privilege flags */
priv(rp)->s_trap_mask= SRV_T; /* allowed traps */
ipc_to_m = SRV_M; /* allowed targets */
kcalls = SRV_KC; /* allowed kernel calls */
priv(rp)->s_sig_mgr = SRV_SM; /* signal manager */
rp->p_priority = SRV_Q; /* priority queue */
rp->p_quantum_size_ms = SRV_QT; /* quantum size */
}
/* Fill in target mask. */
memset(&map, 0, sizeof(map));
if (ipc_to_m == ALL_M) {
for(j = 0; j < NR_SYS_PROCS; j++)
set_sys_bit(map, j);
}
fill_sendto_mask(rp, &map);
/* Fill in kernel call mask. */
for(j = 0; j < SYS_CALL_MASK_SIZE; j++) {
priv(rp)->s_k_call_mask[j] = (kcalls == NO_C ? 0 : (~0));
}
}
else {
/* Don't let the process run for now. */
RTS_SET(rp, RTS_NO_PRIV | RTS_NO_QUANTUM);
}
/* Arch-specific state initialization. */
arch_boot_proc(ip, rp);
/* scheduling functions depend on proc_ptr pointing somewhere. */
if(!get_cpulocal_var(proc_ptr))
get_cpulocal_var(proc_ptr) = rp;
/* Process isn't scheduled until VM has set up a pagetable for it. */
if(rp->p_nr != VM_PROC_NR && rp->p_nr >= 0) {
rp->p_rts_flags |= RTS_VMINHIBIT;
rp->p_rts_flags |= RTS_BOOTINHIBIT;
}
rp->p_rts_flags |= RTS_PROC_STOP;
rp->p_rts_flags &= ~RTS_SLOT_FREE;
DEBUGEXTRA(("done\n"));
}
/* update boot procs info for VM */
memcpy(kinfo.boot_procs, image, sizeof(kinfo.boot_procs));
#define IPCNAME(n) { \
assert((n) >= 0 && (n) <= IPCNO_HIGHEST); \
assert(!ipc_call_names[n]); \
ipc_call_names[n] = #n; \
}
arch_post_init();
IPCNAME(SEND);
IPCNAME(RECEIVE);
IPCNAME(SENDREC);
IPCNAME(NOTIFY);
IPCNAME(SENDNB);
IPCNAME(SENDA);
/* System and processes initialization */
memory_init();
DEBUGEXTRA(("system_init()... "));
system_init();
DEBUGEXTRA(("done\n"));
/* The bootstrap phase is over, so we can add the physical
* memory used for it to the free list.
*/
add_memmap(&kinfo, kinfo.bootstrap_start, kinfo.bootstrap_len);
#ifdef CONFIG_SMP
if (config_no_apic) {
BOOT_VERBOSE(printf("APIC disabled, disables SMP, using legacy PIC\n"));
smp_single_cpu_fallback();
} else if (config_no_smp) {
BOOT_VERBOSE(printf("SMP disabled, using legacy PIC\n"));
smp_single_cpu_fallback();
} else {
smp_init();
/*
* if smp_init() returns it means that it failed and we try to finish
* single CPU booting
*/
bsp_finish_booting();
}
#else
/*
* if configured for a single CPU, we are already on the kernel stack which we
* are going to use everytime we execute kernel code. We finish booting and we
* never return here
*/
bsp_finish_booting();
#endif
NOT_REACHABLE;
}
/*===========================================================================*
* announce *
*===========================================================================*/
static void announce(void)
{
/* Display the MINIX startup banner. */
printf("\nMINIX %s.%s. "
#ifdef _VCS_REVISION
"(" _VCS_REVISION ")\n"
#endif
"Copyright 2012, Vrije Universiteit, Amsterdam, The Netherlands\n",
OS_RELEASE, OS_VERSION);
printf("MINIX is open source software, see http://www.minix3.org\n");
}
/*===========================================================================*
* prepare_shutdown *
*===========================================================================*/
void prepare_shutdown(const int how)
{
/* This function prepares to shutdown MINIX. */
static timer_t shutdown_timer;
/* Continue after 1 second, to give processes a chance to get scheduled to
* do shutdown work. Set a watchog timer to call shutdown(). The timer
* argument passes the shutdown status.
*/
printf("MINIX will now be shut down ...\n");
tmr_arg(&shutdown_timer)->ta_int = how;
set_timer(&shutdown_timer, get_monotonic() + system_hz, minix_shutdown);
}
/*===========================================================================*
* shutdown *
*===========================================================================*/
void minix_shutdown(timer_t *tp)
{
/* This function is called from prepare_shutdown or stop_sequence to bring
* down MINIX. How to shutdown is in the argument: RBT_HALT (return to the
* monitor), RBT_RESET (hard reset).
*/
int how;
#ifdef CONFIG_SMP
/*
* FIXME
*
* we will need to stop timers on all cpus if SMP is enabled and put them in
* such a state that we can perform the whole boot process once restarted from
* monitor again
*/
if (ncpus > 1)
smp_shutdown_aps();
#endif
hw_intr_disable_all();
stop_local_timer();
how = tp ? tmr_arg(tp)->ta_int : RBT_PANIC;
/* Show shutdown message */
direct_cls();
switch(how) {
case RBT_HALT:
direct_print("MINIX has halted. "
"It is safe to turn off your computer.\n");
break;
case RBT_POWEROFF:
direct_print("MINIX has halted and will now power off.\n");
break;
case RBT_DEFAULT:
case RBT_REBOOT:
case RBT_RESET:
default:
direct_print("MINIX will now reset.\n");
break;
}
arch_shutdown(how);
}
/*===========================================================================*
* cstart *
*===========================================================================*/
void cstart()
{
/* Perform system initializations prior to calling main(). Most settings are
* determined with help of the environment strings passed by MINIX' loader.
*/
register char *value; /* value in key=value pair */
int h;
/* low-level initialization */
prot_init();
/* determine verbosity */
if ((value = env_get(VERBOSEBOOTVARNAME)))
verboseboot = atoi(value);
/* Get clock tick frequency. */
value = env_get("hz");
if(value)
system_hz = atoi(value);
if(!value || system_hz < 2 || system_hz > 50000) /* sanity check */
system_hz = DEFAULT_HZ;
DEBUGEXTRA(("cstart\n"));
/* Record miscellaneous information for user-space servers. */
kinfo.nr_procs = NR_PROCS;
kinfo.nr_tasks = NR_TASKS;
strlcpy(kinfo.release, OS_RELEASE, sizeof(kinfo.release));
strlcpy(kinfo.version, OS_VERSION, sizeof(kinfo.version));
/* Load average data initialization. */
kloadinfo.proc_last_slot = 0;
for(h = 0; h < _LOAD_HISTORY; h++)
kloadinfo.proc_load_history[h] = 0;
#ifdef USE_APIC
value = env_get("no_apic");
if(value)
config_no_apic = atoi(value);
else
config_no_apic = 1;
value = env_get("apic_timer_x");
if(value)
config_apic_timer_x = atoi(value);
else
config_apic_timer_x = 1;
#endif
#ifdef USE_WATCHDOG
value = env_get("watchdog");
if (value)
watchdog_enabled = atoi(value);
#endif
#ifdef CONFIG_SMP
if (config_no_apic)
config_no_smp = 1;
value = env_get("no_smp");
if(value)
config_no_smp = atoi(value);
else
config_no_smp = 0;
#endif
DEBUGEXTRA(("intr_init(0)\n"));
intr_init(0);
arch_init();
}
/*===========================================================================*
* get_value *
*===========================================================================*/
char *get_value(
const char *params, /* boot monitor parameters */
const char *name /* key to look up */
)
{
/* Get environment value - kernel version of getenv to avoid setting up the
* usual environment array.
*/
register const char *namep;
register char *envp;
for (envp = (char *) params; *envp != 0;) {
for (namep = name; *namep != 0 && *namep == *envp; namep++, envp++)
;
if (*namep == '\0' && *envp == '=') return(envp + 1);
while (*envp++ != 0)
;
}
return(NULL);
}
/*===========================================================================*
* env_get *
*===========================================================================*/
char *env_get(const char *name)
{
return get_value(kinfo.param_buf, name);
}
void cpu_print_freq(unsigned cpu)
{
u64_t freq;
freq = cpu_get_freq(cpu);
printf("CPU %d freq %lu MHz\n", cpu, div64u(freq, 1000000));
}
int is_fpu(void)
{
return get_cpulocal_var(fpu_presence);
}
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