minix/kernel/arch/i386/arch_system.c
Tomas Hruby a774cc832f do_ipc() rearrangements
this patch does not add or change any functionality of do_ipc(), it
only makes things a little cleaner (hopefully).

Until now do_ipc() was responsible for handling all ipc calls. The
catch is that SENDA is fairly different which results in some ugly
code like this typecasting and variables naming which does not make
much sense for SENDA and makes the code hard to read.

result = mini_senda(caller_ptr, (asynmsg_t *)m_ptr, (size_t)src_dst_e);

As it is called directly from assembly, the new do_ipc() takes as
input values of 3 registers in reg_t variables (it used to be 4,
however, bit_map wasn't used so I removed it), does the checks common
to all ipc calls and call the appropriate handler either for
do_sync_ipc() (all except SENDA) or mini_senda() (for SENDA) while
typecasting the reg_t values correctly. As a result, handling SENDA
differences in do_sync_ipc() is no more needed. Also the code that
uses msg_size variable is improved a little bit.

arch_do_syscall() is simplified too.
2010-04-06 11:24:26 +00:00

473 lines
10 KiB
C

/* system dependent functions for use inside the whole kernel. */
#include "kernel/kernel.h"
#include <unistd.h>
#include <ctype.h>
#include <string.h>
#include <machine/cmos.h>
#include <machine/bios.h>
#include <minix/portio.h>
#include <minix/cpufeature.h>
#include <a.out.h>
#include <assert.h>
#include "archconst.h"
#include "proto.h"
#include "kernel/proc.h"
#include "kernel/debug.h"
#ifdef CONFIG_APIC
#include "apic.h"
#endif
/* set MP and NE flags to handle FPU exceptions in native mode. */
#define CR0_MP_NE 0x0022
/* set CR4.OSFXSR[bit 9] if FXSR is supported. */
#define CR4_OSFXSR (1L<<9)
/* set OSXMMEXCPT[bit 10] if we provide #XM handler. */
#define CR4_OSXMMEXCPT (1L<<10)
FORWARD _PROTOTYPE( void ser_debug, (int c));
PUBLIC void arch_monitor(void)
{
monitor();
}
PUBLIC int cpu_has_tsc;
PUBLIC void arch_shutdown(const int how)
{
/* Mask all interrupts, including the clock. */
outb( INT_CTLMASK, ~0);
if(minix_panicing) {
/* We're panicing? Then retrieve and decode currently
* loaded segment selectors.
*/
printseg("cs: ", 1, proc_ptr, read_cs());
printseg("ds: ", 0, proc_ptr, read_ds());
if(read_ds() != read_ss()) {
printseg("ss: ", 0, NULL, read_ss());
}
}
if(how != RBT_RESET) {
/* return to boot monitor */
outb( INT_CTLMASK, 0);
outb( INT2_CTLMASK, 0);
/* Return to the boot monitor. Set
* the program if not already done.
*/
if (how != RBT_MONITOR)
arch_set_params("", 1);
if(minix_panicing) {
int source, dest;
static char mybuffer[sizeof(params_buffer)];
const char *lead = "echo \\n*** kernel messages:\\n";
const int leadlen = strlen(lead);
strcpy(mybuffer, lead);
#define DECSOURCE source = (source - 1 + _KMESS_BUF_SIZE) % _KMESS_BUF_SIZE
dest = sizeof(mybuffer)-1;
mybuffer[dest--] = '\0';
source = kmess.km_next;
DECSOURCE;
while(dest >= leadlen) {
const char c = kmess.km_buf[source];
if(c == '\n') {
mybuffer[dest--] = 'n';
mybuffer[dest] = '\\';
} else if(isprint(c) &&
c != '\'' && c != '"' &&
c != '\\' && c != ';') {
mybuffer[dest] = c;
} else mybuffer[dest] = ' ';
DECSOURCE;
dest--;
}
arch_set_params(mybuffer, strlen(mybuffer)+1);
}
arch_monitor();
} else {
/* Reset the system by forcing a processor shutdown. First stop
* the BIOS memory test by setting a soft reset flag.
*/
u16_t magic = STOP_MEM_CHECK;
phys_copy(vir2phys(&magic), SOFT_RESET_FLAG_ADDR,
SOFT_RESET_FLAG_SIZE);
reset();
}
}
/* address of a.out headers, set in mpx386.s */
phys_bytes aout;
PUBLIC void arch_get_aout_headers(const int i, struct exec *h)
{
/* The bootstrap loader created an array of the a.out headers at
* absolute address 'aout'. Get one element to h.
*/
phys_copy(aout + i * A_MINHDR, vir2phys(h), (phys_bytes) A_MINHDR);
}
PRIVATE void tss_init(struct tss_s * tss, void * kernel_stack,
const unsigned cpu)
{
/*
* make space for process pointer and cpu id and point to the first
* usable word
*/
tss->sp0 = ((unsigned) kernel_stack) - 2 * sizeof(void *);
tss->ss0 = DS_SELECTOR;
/*
* set the cpu id at the top of the stack so we know on which cpu is
* this stak in use when we trap to kernel
*/
*((reg_t *)(tss->sp0 + 1 * sizeof(reg_t))) = cpu;
}
PUBLIC void arch_init(void)
{
unsigned short cw, sw;
fninit();
sw = fnstsw();
fnstcw(&cw);
if((sw & 0xff) == 0 &&
(cw & 0x103f) == 0x3f) {
/* We have some sort of FPU, but don't check exact model.
* Set CR0_NE and CR0_MP to handle fpu exceptions
* in native mode. */
write_cr0(read_cr0() | CR0_MP_NE);
fpu_presence = 1;
if(_cpufeature(_CPUF_I386_FXSR)) {
register struct proc *rp;
phys_bytes aligned_fp_area;
/* Enable FXSR feature usage. */
write_cr4(read_cr4() | CR4_OSFXSR | CR4_OSXMMEXCPT);
osfxsr_feature = 1;
for (rp = BEG_PROC_ADDR; rp < END_PROC_ADDR; ++rp) {
/* FXSR requires 16-byte alignment of memory
* image, but unfortunately some old tools
* (probably linker) ignores ".balign 16"
* applied to our memory image.
* Thus we have to do manual alignment.
*/
aligned_fp_area =
(phys_bytes) &rp->p_fpu_state.fpu_image;
if(aligned_fp_area % FPUALIGN) {
aligned_fp_area += FPUALIGN -
(aligned_fp_area % FPUALIGN);
}
rp->p_fpu_state.fpu_save_area_p =
(void *) aligned_fp_area;
}
} else {
osfxsr_feature = 0;
}
} else {
/* No FPU presents. */
fpu_presence = 0;
osfxsr_feature = 0;
return;
}
#ifdef CONFIG_APIC
/*
* this is setting kernel segments to cover most of the phys memory. The
* value is high enough to reach local APIC nad IOAPICs before paging is
* turned on.
*/
prot_set_kern_seg_limit(0xfff00000);
reload_ds();
#endif
idt_init();
tss_init(&tss, &k_boot_stktop, 0);
#if defined(CONFIG_APIC) && !defined(CONFIG_SMP)
if (config_no_apic) {
BOOT_VERBOSE(printf("APIC disabled, using legacy PIC\n"));
}
else if (!apic_single_cpu_init()) {
BOOT_VERBOSE(printf("APIC not present, using legacy PIC\n"));
}
#endif
}
#define COM1_BASE 0x3F8
#define COM1_THR (COM1_BASE + 0)
#define COM1_RBR (COM1_BASE + 0)
#define COM1_LSR (COM1_BASE + 5)
#define LSR_DR 0x01
#define LSR_THRE 0x20
PUBLIC void ser_putc(char c)
{
int i;
int lsr, thr;
lsr= COM1_LSR;
thr= COM1_THR;
for (i= 0; i<100000; i++)
{
if (inb( lsr) & LSR_THRE)
break;
}
outb( thr, c);
}
/*===========================================================================*
* do_ser_debug *
*===========================================================================*/
PUBLIC void do_ser_debug()
{
u8_t c, lsr;
lsr= inb(COM1_LSR);
if (!(lsr & LSR_DR))
return;
c = inb(COM1_RBR);
ser_debug(c);
}
PRIVATE void ser_dump_queues(void)
{
int q;
for(q = 0; q < NR_SCHED_QUEUES; q++) {
struct proc *p;
if(rdy_head[q])
printf("%2d: ", q);
for(p = rdy_head[q]; p; p = p->p_nextready) {
printf("%s / %d ", p->p_name, p->p_endpoint);
}
printf("\n");
}
}
PRIVATE void ser_dump_segs(void)
{
struct proc *pp;
for (pp= BEG_PROC_ADDR; pp < END_PROC_ADDR; pp++)
{
if (isemptyp(pp))
continue;
printf("%d: %s ep %d\n", proc_nr(pp), pp->p_name, pp->p_endpoint);
printseg("cs: ", 1, pp, pp->p_reg.cs);
printseg("ds: ", 0, pp, pp->p_reg.ds);
if(pp->p_reg.ss != pp->p_reg.ds) {
printseg("ss: ", 0, pp, pp->p_reg.ss);
}
}
}
PRIVATE void ser_debug(const int c)
{
serial_debug_active = 1;
switch(c)
{
case 'Q':
minix_shutdown(NULL);
NOT_REACHABLE;
case '1':
ser_dump_proc();
break;
case '2':
ser_dump_queues();
break;
case '3':
ser_dump_segs();
break;
#if DEBUG_TRACE
#define TOGGLECASE(ch, flag) \
case ch: { \
if(verboseflags & flag) { \
verboseflags &= ~flag; \
printf("%s disabled\n", #flag); \
} else { \
verboseflags |= flag; \
printf("%s enabled\n", #flag); \
} \
break; \
}
TOGGLECASE('8', VF_SCHEDULING)
TOGGLECASE('9', VF_PICKPROC)
#endif
}
serial_debug_active = 0;
}
PRIVATE void printslot(struct proc *pp, const int level)
{
struct proc *depproc = NULL;
endpoint_t dep;
#define COL { int i; for(i = 0; i < level; i++) printf("> "); }
if(level >= NR_PROCS) {
printf("loop??\n");
return;
}
COL
printf("%d: %s %d prio %d time %d/%d cycles 0x%x%08x cr3 0x%lx rts %s misc %s sched %s",
proc_nr(pp), pp->p_name, pp->p_endpoint,
pp->p_priority, pp->p_user_time,
pp->p_sys_time, pp->p_cycles.hi, pp->p_cycles.lo, pp->p_seg.p_cr3,
rtsflagstr(pp->p_rts_flags), miscflagstr(pp->p_misc_flags),
schedulerstr(pp->p_scheduler));
if((dep = P_BLOCKEDON(pp)) != NONE) {
printf(" blocked on: ");
if(dep == ANY) {
printf(" ANY\n");
} else {
int procno;
if(!isokendpt(dep, &procno)) {
printf(" ??? %d\n", dep);
} else {
depproc = proc_addr(procno);
if(isemptyp(depproc)) {
printf(" empty slot %d???\n", procno);
depproc = NULL;
} else {
printf(" %s\n", depproc->p_name);
}
}
}
} else {
printf("\n");
}
COL
proc_stacktrace(pp);
if(depproc)
printslot(depproc, level+1);
}
PUBLIC void ser_dump_proc()
{
struct proc *pp;
for (pp= BEG_PROC_ADDR; pp < END_PROC_ADDR; pp++)
{
if (isemptyp(pp))
continue;
printslot(pp, 0);
}
}
#if SPROFILE
PUBLIC int arch_init_profile_clock(const u32_t freq)
{
int r;
/* Set CMOS timer frequency. */
outb(RTC_INDEX, RTC_REG_A);
outb(RTC_IO, RTC_A_DV_OK | freq);
/* Enable CMOS timer interrupts. */
outb(RTC_INDEX, RTC_REG_B);
r = inb(RTC_IO);
outb(RTC_INDEX, RTC_REG_B);
outb(RTC_IO, r | RTC_B_PIE);
/* Mandatory read of CMOS register to enable timer interrupts. */
outb(RTC_INDEX, RTC_REG_C);
inb(RTC_IO);
return CMOS_CLOCK_IRQ;
}
PUBLIC void arch_stop_profile_clock(void)
{
int r;
/* Disable CMOS timer interrupts. */
outb(RTC_INDEX, RTC_REG_B);
r = inb(RTC_IO);
outb(RTC_INDEX, RTC_REG_B);
outb(RTC_IO, r & ~RTC_B_PIE);
}
PUBLIC void arch_ack_profile_clock(void)
{
/* Mandatory read of CMOS register to re-enable timer interrupts. */
outb(RTC_INDEX, RTC_REG_C);
inb(RTC_IO);
}
#endif
#define COLOR_BASE 0xB8000L
PRIVATE void cons_setc(const int pos, const int c)
{
char ch;
ch= c;
phys_copy(vir2phys((vir_bytes)&ch), COLOR_BASE+(20*80+pos)*2, 1);
}
PRIVATE void cons_seth(int pos, int n)
{
n &= 0xf;
if (n < 10)
cons_setc(pos, '0'+n);
else
cons_setc(pos, 'A'+(n-10));
}
/* Saved by mpx386.s into these variables. */
u32_t params_size, params_offset, mon_ds;
PUBLIC int arch_get_params(char *params, int maxsize)
{
phys_copy(seg2phys(mon_ds) + params_offset, vir2phys(params),
MIN(maxsize, params_size));
params[maxsize-1] = '\0';
return OK;
}
PUBLIC int arch_set_params(char *params, int size)
{
if(size > params_size)
return E2BIG;
phys_copy(vir2phys(params), seg2phys(mon_ds) + params_offset, size);
return OK;
}
PUBLIC void arch_do_syscall(struct proc *proc)
{
/* do_ipc assumes that it's running because of the current process */
assert(proc == proc_ptr);
/* Make the system call, for real this time. */
proc->p_reg.retreg =
do_ipc(proc->p_reg.cx, proc->p_reg.retreg, proc->p_reg.bx);
}
PUBLIC struct proc * arch_finish_schedcheck(void)
{
char * stk;
stk = (char *)tss.sp0;
/* set pointer to the process to run on the stack */
*((reg_t *)stk) = (reg_t) proc_ptr;
return proc_ptr;
}