175 lines
3.1 KiB
C
175 lines
3.1 KiB
C
/*
|
|
* Minimal PIO-based (non-interrupt-driven) IDE driver code.
|
|
* For information about what all this IDE/ATA magic means,
|
|
* see the materials available on the class references page.
|
|
*/
|
|
|
|
#include "types.h"
|
|
#include "param.h"
|
|
#include "mmu.h"
|
|
#include "proc.h"
|
|
#include "defs.h"
|
|
#include "x86.h"
|
|
|
|
#define IDE_BSY 0x80
|
|
#define IDE_DRDY 0x40
|
|
#define IDE_DF 0x20
|
|
#define IDE_ERR 0x01
|
|
|
|
struct ide_request {
|
|
uint32_t secno;
|
|
void *dst;
|
|
unsigned nsecs;
|
|
};
|
|
struct ide_request request[NREQUEST];
|
|
int head, tail;
|
|
|
|
static int diskno = 0;
|
|
int disk_channel;
|
|
|
|
static int
|
|
ide_wait_ready(int check_error)
|
|
{
|
|
int r;
|
|
|
|
while (((r = inb(0x1F7)) & (IDE_BSY|IDE_DRDY)) != IDE_DRDY)
|
|
/* do nothing */;
|
|
|
|
if (check_error && (r & (IDE_DF|IDE_ERR)) != 0)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
ide_init(void)
|
|
{
|
|
cprintf("ide_init: enable IRQ 14\n");
|
|
irq_setmask_8259A(irq_mask_8259A & ~(1<<14));
|
|
ide_wait_ready(0);
|
|
}
|
|
|
|
void
|
|
ide_intr(void)
|
|
{
|
|
cprintf("ide_intr\n");
|
|
wakeup(&request[tail]);
|
|
}
|
|
|
|
int
|
|
ide_probe_disk1(void)
|
|
{
|
|
int r, x;
|
|
|
|
// wait for Device 0 to be ready
|
|
ide_wait_ready(0);
|
|
|
|
// switch to Device 1
|
|
outb(0x1F6, 0xE0 | (1<<4));
|
|
|
|
// check for Device 1 to be ready for a while
|
|
for (x = 0; x < 1000 && (r = inb(0x1F7)) == 0; x++)
|
|
/* do nothing */;
|
|
|
|
// switch back to Device 0
|
|
outb(0x1F6, 0xE0 | (0<<4));
|
|
|
|
cprintf("Device 1 presence: %d\n", (x < 1000));
|
|
return (x < 1000);
|
|
}
|
|
|
|
void
|
|
ide_set_disk(int d)
|
|
{
|
|
if (d != 0 && d != 1)
|
|
panic("bad disk number");
|
|
diskno = d;
|
|
}
|
|
|
|
void
|
|
ide_start_request (void)
|
|
{
|
|
struct ide_request *r;
|
|
|
|
if (head == tail) {
|
|
r = &request[tail];
|
|
ide_wait_ready(0);
|
|
outb(0x3f6, 0);
|
|
outb(0x1F2, r->nsecs);
|
|
outb(0x1F3, r->secno & 0xFF);
|
|
outb(0x1F4, (r->secno >> 8) & 0xFF);
|
|
outb(0x1F5, (r->secno >> 16) & 0xFF);
|
|
outb(0x1F6, 0xE0 | ((diskno&1)<<4) | ((r->secno>>24)&0x0F));
|
|
outb(0x1F7, 0x20); // CMD 0x20 means read sector
|
|
}
|
|
}
|
|
|
|
void *
|
|
ide_start_read(uint32_t secno, void *dst, unsigned nsecs)
|
|
{
|
|
struct ide_request *r;
|
|
|
|
if(nsecs > 256)
|
|
panic("ide_start_read: nsecs too large");
|
|
|
|
while ((head + 1) % NREQUEST == tail)
|
|
sleep (&disk_channel);
|
|
|
|
r = &request[head];
|
|
r->secno = secno;
|
|
r->dst = dst;
|
|
r->nsecs = nsecs;
|
|
|
|
ide_start_request();
|
|
|
|
head = (head + 1) % NREQUEST;
|
|
|
|
return r;
|
|
}
|
|
|
|
int
|
|
ide_finish_read(void *c)
|
|
{
|
|
int r = 0;
|
|
struct ide_request *req = (struct ide_request *) c;
|
|
|
|
for (; req->nsecs > 0; req->nsecs--, req->dst += 512) {
|
|
if ((r = ide_wait_ready(1)) < 0)
|
|
break;
|
|
insl(0x1F0, req->dst, 512/4);
|
|
}
|
|
|
|
if ((head + 1) % NREQUEST == tail) {
|
|
wakeup(&disk_channel);
|
|
}
|
|
|
|
tail = (tail + 1) % NREQUEST;
|
|
ide_start_request();
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
ide_write(uint32_t secno, const void *src, unsigned nsecs)
|
|
{
|
|
int r;
|
|
|
|
if(nsecs > 256)
|
|
panic("ide_write");
|
|
|
|
ide_wait_ready(0);
|
|
|
|
outb(0x1F2, nsecs);
|
|
outb(0x1F3, secno & 0xFF);
|
|
outb(0x1F4, (secno >> 8) & 0xFF);
|
|
outb(0x1F5, (secno >> 16) & 0xFF);
|
|
outb(0x1F6, 0xE0 | ((diskno&1)<<4) | ((secno>>24)&0x0F));
|
|
outb(0x1F7, 0x30); // CMD 0x30 means write sector
|
|
|
|
for (; nsecs > 0; nsecs--, src += 512) {
|
|
if ((r = ide_wait_ready(1)) < 0)
|
|
return r;
|
|
outsl(0x1F0, src, 512/4);
|
|
}
|
|
|
|
return 0;
|
|
}
|