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xv6-cs450/mp.c
kaashoek a44ee3cde8 stick mpstack in cpu structure
2006-06-26 16:40:43 +00:00

368 lines
9.9 KiB
C
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#include "types.h"
#include "mp.h"
#include "defs.h"
#include "memlayout.h"
#include "param.h"
#include "x86.h"
#include "mmu.h"
/*
* Credit: Plan 9 sources, Intel MP spec, and Cliff Frey
*/
enum { /* Local APIC registers */
LAPIC_ID = 0x0020, /* ID */
LAPIC_VER = 0x0030, /* Version */
LAPIC_TPR = 0x0080, /* Task Priority */
LAPIC_APR = 0x0090, /* Arbitration Priority */
LAPIC_PPR = 0x00A0, /* Processor Priority */
LAPIC_EOI = 0x00B0, /* EOI */
LAPIC_LDR = 0x00D0, /* Logical Destination */
LAPIC_DFR = 0x00E0, /* Destination Format */
LAPIC_SVR = 0x00F0, /* Spurious Interrupt Vector */
LAPIC_ISR = 0x0100, /* Interrupt Status (8 registers) */
LAPIC_TMR = 0x0180, /* Trigger Mode (8 registers) */
LAPIC_IRR = 0x0200, /* Interrupt Request (8 registers) */
LAPIC_ESR = 0x0280, /* Error Status */
LAPIC_ICRLO = 0x0300, /* Interrupt Command */
LAPIC_ICRHI = 0x0310, /* Interrupt Command [63:32] */
LAPIC_TIMER = 0x0320, /* Local Vector Table 0 (TIMER) */
LAPIC_PCINT = 0x0340, /* Performance Counter LVT */
LAPIC_LINT0 = 0x0350, /* Local Vector Table 1 (LINT0) */
LAPIC_LINT1 = 0x0360, /* Local Vector Table 2 (LINT1) */
LAPIC_ERROR = 0x0370, /* Local Vector Table 3 (ERROR) */
LAPIC_TICR = 0x0380, /* Timer Initial Count */
LAPIC_TCCR = 0x0390, /* Timer Current Count */
LAPIC_TDCR = 0x03E0, /* Timer Divide Configuration */
};
enum { /* LAPIC_SVR */
LAPIC_ENABLE = 0x00000100, /* Unit Enable */
LAPIC_FOCUS = 0x00000200, /* Focus Processor Checking Disable */
};
enum { /* LAPIC_ICRLO */
/* [14] IPI Trigger Mode Level (RW) */
LAPIC_DEASSERT = 0x00000000, /* Deassert level-sensitive interrupt */
LAPIC_ASSERT = 0x00004000, /* Assert level-sensitive interrupt */
/* [17:16] Remote Read Status */
LAPIC_INVALID = 0x00000000, /* Invalid */
LAPIC_WAIT = 0x00010000, /* In-Progress */
LAPIC_VALID = 0x00020000, /* Valid */
/* [19:18] Destination Shorthand */
LAPIC_FIELD = 0x00000000, /* No shorthand */
LAPIC_SELF = 0x00040000, /* Self is single destination */
LAPIC_ALLINC = 0x00080000, /* All including self */
LAPIC_ALLEXC = 0x000C0000, /* All Excluding self */
};
enum { /* LAPIC_ESR */
LAPIC_SENDCS = 0x00000001, /* Send CS Error */
LAPIC_RCVCS = 0x00000002, /* Receive CS Error */
LAPIC_SENDACCEPT = 0x00000004, /* Send Accept Error */
LAPIC_RCVACCEPT = 0x00000008, /* Receive Accept Error */
LAPIC_SENDVECTOR = 0x00000020, /* Send Illegal Vector */
LAPIC_RCVVECTOR = 0x00000040, /* Receive Illegal Vector */
LAPIC_REGISTER = 0x00000080, /* Illegal Register Address */
};
enum { /* LAPIC_TIMER */
/* [17] Timer Mode (RW) */
LAPIC_ONESHOT = 0x00000000, /* One-shot */
LAPIC_PERIODIC = 0x00020000, /* Periodic */
/* [19:18] Timer Base (RW) */
LAPIC_CLKIN = 0x00000000, /* use CLKIN as input */
LAPIC_TMBASE = 0x00040000, /* use TMBASE */
LAPIC_DIVIDER = 0x00080000, /* use output of the divider */
};
enum { /* LAPIC_TDCR */
LAPIC_X2 = 0x00000000, /* divide by 2 */
LAPIC_X4 = 0x00000001, /* divide by 4 */
LAPIC_X8 = 0x00000002, /* divide by 8 */
LAPIC_X16 = 0x00000003, /* divide by 16 */
LAPIC_X32 = 0x00000008, /* divide by 32 */
LAPIC_X64 = 0x00000009, /* divide by 64 */
LAPIC_X128 = 0x0000000A, /* divide by 128 */
LAPIC_X1 = 0x0000000B, /* divide by 1 */
};
#define APBOOTCODE 0x7000 // XXX hack
#define MPSTACK 512
static struct MP* mp; // The MP floating point structure
static uint32_t *lapicaddr;
static struct cpu {
uint8_t apicid; // Local APIC ID
int lintr[2]; // Local APIC
char mpstack[MPSTACK]; // per-cpu start-up stack, only used to get into main()
} cpus[NCPU];
static int ncpu;
static struct cpu *bcpu;
static int
lapic_read(int r)
{
return *(lapicaddr+(r/sizeof(*lapicaddr)));
}
static void
lapic_write(int r, int data)
{
*(lapicaddr+(r/sizeof(*lapicaddr))) = data;
}
void
lapic_init(int c)
{
uint32_t r, lvt;
cprintf("lapic_init %d\n", c);
lapic_write(LAPIC_DFR, 0xFFFFFFFF);
r = (lapic_read(LAPIC_ID)>>24) & 0xFF;
lapic_write(LAPIC_LDR, (1<<r)<<24);
lapic_write(LAPIC_TPR, 0xFF);
lapic_write(LAPIC_SVR, LAPIC_ENABLE|(IRQ_OFFSET+IRQ_SPURIOUS));
/*
* Set the local interrupts. It's likely these should just be
* masked off for SMP mode as some Pentium Pros have problems if
* LINT[01] are set to ExtINT.
* Acknowledge any outstanding interrupts.
*/
lapic_write(LAPIC_LINT0, cpus[c].lintr[0]);
lapic_write(LAPIC_LINT1, cpus[c].lintr[1]);
lapic_write(LAPIC_EOI, 0);
lvt = (lapic_read(LAPIC_VER)>>16) & 0xFF;
if(lvt >= 4)
lapic_write(LAPIC_PCINT, APIC_IMASK);
lapic_write(LAPIC_ERROR, IRQ_OFFSET+IRQ_ERROR);
lapic_write(LAPIC_ESR, 0);
lapic_read(LAPIC_ESR);
/*
* Issue an INIT Level De-Assert to synchronise arbitration ID's.
*/
lapic_write(LAPIC_ICRHI, 0);
lapic_write(LAPIC_ICRLO, LAPIC_ALLINC|APIC_LEVEL|LAPIC_DEASSERT|APIC_INIT);
while(lapic_read(LAPIC_ICRLO) & APIC_DELIVS)
;
/*
* Do not allow acceptance of interrupts until all initialisation
* for this processor is done. For the bootstrap processor this can be
* early duing initialisation. For the application processors this should
* be after the bootstrap processor has lowered priority and is accepting
* interrupts.
*/
lapic_write(LAPIC_TPR, 0);
cprintf("Done init of an apic\n");
}
static void
lapic_online(void)
{
lapic_write(LAPIC_TPR, 0);
}
int
cpu(void)
{
return (lapic_read(LAPIC_ID)>>24) & 0xFF;
}
static void
lapic_startap(struct cpu *c, int v)
{
int crhi, i;
volatile int j = 0;
crhi = c->apicid<<24;
lapic_write(LAPIC_ICRHI, crhi);
lapic_write(LAPIC_ICRLO, LAPIC_FIELD|APIC_LEVEL|LAPIC_ASSERT|APIC_INIT);
while (j++ < 10000) {;}
lapic_write(LAPIC_ICRLO, LAPIC_FIELD|APIC_LEVEL|LAPIC_DEASSERT|APIC_INIT);
while (j++ < 1000000) {;}
// in p9 code, this was i < 2, which is what the spec says on page B-3
for(i = 0; i < 1; i++){
lapic_write(LAPIC_ICRHI, crhi);
lapic_write(LAPIC_ICRLO, LAPIC_FIELD|APIC_EDGE|APIC_STARTUP|(v/PGSIZE));
while (j++ < 100000) {;}
}
}
static struct MP*
mp_scan(uint8_t *addr, int len)
{
uint8_t *e, *p, sum;
int i;
cprintf("scanning: 0x%x\n", (uint32_t)addr);
e = addr+len;
for(p = addr; p < e; p += sizeof(struct MP)){
if(memcmp(p, "_MP_", 4))
continue;
sum = 0;
for(i = 0; i < sizeof(struct MP); i++)
sum += p[i];
if(sum == 0)
return (struct MP *)p;
}
return 0;
}
static struct MP*
mp_search(void)
{
uint8_t *bda;
uint32_t p;
struct MP *mp;
/*
* Search for the MP Floating Pointer Structure, which according to the
* spec is in one of the following three locations:
* 1) in the first KB of the EBDA;
* 2) in the last KB of system base memory;
* 3) in the BIOS ROM between 0xE0000 and 0xFFFFF.
*/
bda = (uint8_t*) 0x400;
if((p = (bda[0x0F]<<8)|bda[0x0E])){
if((mp = mp_scan((uint8_t*) p, 1024)))
return mp;
}
else{
p = ((bda[0x14]<<8)|bda[0x13])*1024;
if((mp = mp_scan((uint8_t*)p-1024, 1024)))
return mp;
}
return mp_scan((uint8_t*)0xF0000, 0x10000);
}
static int
mp_detect(void)
{
struct MPCTB *pcmp;
uint8_t *p, sum;
uint32_t length;
/*
* Search for an MP configuration table. For now,
* don't accept the default configurations (physaddr == 0).
* Check for correct signature, calculate the checksum and,
* if correct, check the version.
* To do: check extended table checksum.
*/
if((mp = mp_search()) == 0 || mp->physaddr == 0)
return 1;
pcmp = (struct MPCTB *) mp->physaddr;
if(memcmp(pcmp, "PCMP", 4))
return 2;
length = pcmp->length;
sum = 0;
for(p = (uint8_t*)pcmp; length; length--)
sum += *p++;
if(sum || (pcmp->version != 1 && pcmp->version != 4))
return 3;
cprintf("MP spec rev #: %x\n", mp->specrev);
return 0;
}
int
mp_isbcpu()
{
if (bcpu == 0) return 1;
else return 0;
}
void
mp_init()
{
int r;
uint8_t *p, *e;
struct MPCTB *mpctb;
struct MPPE *proc;
int c;
extern int main();
ncpu = 0;
if ((r = mp_detect()) != 0) return;
cprintf ("This computer is a multiprocessor!\n");
/*
* Run through the table saving information needed for starting
* application processors and initialising any I/O APICs. The table
* is guaranteed to be in order such that only one pass is necessary.
*/
mpctb = (struct MPCTB *) mp->physaddr;
lapicaddr = (uint32_t *) mpctb->lapicaddr;
cprintf("apicaddr: %x\n", lapicaddr);
p = ((uint8_t*)mpctb)+sizeof(struct MPCTB);
e = ((uint8_t*)mpctb)+mpctb->length;
while(p < e) {
switch(*p){
case MPPROCESSOR:
proc = (struct MPPE *) p;
cpus[ncpu].apicid = proc->apicid;
cpus[ncpu].lintr[0] = APIC_IMASK;
cpus[ncpu].lintr[1] = APIC_IMASK;
cprintf("a processor %x\n", cpus[ncpu].apicid);
if (proc->flags & MPBP) {
bcpu = &cpus[ncpu];
}
ncpu++;
p += sizeof(struct MPPE);
continue;
case MPBUS:
p += sizeof(struct MPBE);
continue;
case MPIOAPIC:
cprintf("an I/O APIC\n");
p += sizeof(struct MPIOAPIC);
continue;
case MPIOINTR:
p += sizeof(struct MPIE);
continue;
default:
cprintf("mpinit: unknown PCMP type 0x%x (e-p 0x%x)\n", *p, e-p);
while(p < e){
cprintf("%uX ", *p);
p++;
}
break;
}
}
lapic_init(bcpu-cpus);
cprintf("ncpu: %d boot %d\n", ncpu, bcpu-cpus);
lapic_online();
extern uint8_t _binary_bootother_start[], _binary_bootother_size[];
memmove((void *) APBOOTCODE,_binary_bootother_start,
(uint32_t) _binary_bootother_size);
acquire_spinlock(&kernel_lock);
for(c = 0; c < ncpu; c++){
if (cpus+c == bcpu) continue;
cprintf ("starting processor %d\n", c);
release_grant_spinlock(&kernel_lock, c);
*(unsigned *)(APBOOTCODE-4) = (unsigned) (cpus[c].mpstack) + MPSTACK; // tell it what to use for %esp
*(unsigned *)(APBOOTCODE-8) = (unsigned)&main; // tell it where to jump to
lapic_startap(cpus + c, (uint32_t) APBOOTCODE);
acquire_spinlock(&kernel_lock);
cprintf ("done starting processor %d\n", c);
}
}
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