minor cleanups
This commit is contained in:
rsc
parent
cb30c81860
commit
d7b44dbcfc
1 changed files with 62 additions and 68 deletions
130
ide.c
130
ide.c
|
|
@ -26,20 +26,16 @@ static struct spinlock ide_lock;
|
|||
static struct buf *ide_queue;
|
||||
|
||||
static int disk_1_present;
|
||||
|
||||
static int ide_probe_disk1(void);
|
||||
static void ide_start_request();
|
||||
|
||||
//PAGEBREAK: 10
|
||||
// Wait for IDE disk to become ready.
|
||||
static int
|
||||
ide_wait_ready(int check_error)
|
||||
{
|
||||
int r;
|
||||
|
||||
while(((r = inb(0x1F7)) & (IDE_BSY|IDE_DRDY)) != IDE_DRDY)
|
||||
while(((r = inb(0x1f7)) & IDE_BSY) || !(r & IDE_DRDY))
|
||||
;
|
||||
|
||||
if(check_error && (r & (IDE_DF|IDE_ERR)) != 0)
|
||||
return -1;
|
||||
return 0;
|
||||
|
|
@ -48,105 +44,103 @@ ide_wait_ready(int check_error)
|
|||
void
|
||||
ide_init(void)
|
||||
{
|
||||
int i;
|
||||
|
||||
initlock(&ide_lock, "ide");
|
||||
irq_enable(IRQ_IDE);
|
||||
ioapic_enable(IRQ_IDE, ncpu - 1);
|
||||
ide_wait_ready(0);
|
||||
disk_1_present = ide_probe_disk1();
|
||||
|
||||
// Check if disk 1 is present
|
||||
outb(0x1f6, 0xE0 | (1<<4));
|
||||
for(i=0; i<1000; i++){
|
||||
if(inb(0x1f7) != 0){
|
||||
disk_1_present = 1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
// Probe to see if disk 1 exists (we assume disk 0 exists).
|
||||
static int
|
||||
ide_probe_disk1(void)
|
||||
// Switch back to disk 0.
|
||||
outb(0x1f6, 0xE0 | (0<<4));
|
||||
}
|
||||
|
||||
// Start the request for b. Caller must hold ide_lock.
|
||||
static void
|
||||
ide_start_request(struct buf *b)
|
||||
{
|
||||
int r, x;
|
||||
if(b == 0)
|
||||
panic("ide_start_request");
|
||||
|
||||
// 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++)
|
||||
;
|
||||
|
||||
// switch back to Device 0
|
||||
outb(0x1F6, 0xE0 | (0<<4));
|
||||
|
||||
return x < 1000;
|
||||
outb(0x3f6, 0); // generate interrupt
|
||||
outb(0x1f2, 1); // number of sectors
|
||||
outb(0x1f3, b->sector & 0xff);
|
||||
outb(0x1f4, (b->sector >> 8) & 0xff);
|
||||
outb(0x1f5, (b->sector >> 16) & 0xff);
|
||||
outb(0x1f6, 0xE0 | ((b->dev&1)<<4) | ((b->sector>>24)&0x0f));
|
||||
if(b->flags & B_WRITE){
|
||||
outb(0x1f7, IDE_CMD_WRITE);
|
||||
outsl(0x1f0, b->data, 512/4);
|
||||
}else{
|
||||
outb(0x1f7, IDE_CMD_READ);
|
||||
}
|
||||
}
|
||||
|
||||
// Interrupt handler - wake up the request that just finished.
|
||||
// Interrupt handler.
|
||||
void
|
||||
ide_intr(void)
|
||||
{
|
||||
struct buf *b;
|
||||
|
||||
acquire(&ide_lock);
|
||||
if(ide_queue){
|
||||
if((ide_queue->flags & B_WRITE) == 0)
|
||||
if(ide_wait_ready(1) >= 0)
|
||||
insl(0x1F0, ide_queue->data, 512/4);
|
||||
ide_queue->done = 1;
|
||||
wakeup(ide_queue);
|
||||
ide_queue = ide_queue->qnext;
|
||||
ide_start_request();
|
||||
} else {
|
||||
if((b = ide_queue) == 0){
|
||||
cprintf("stray ide interrupt\n");
|
||||
release(&ide_lock);
|
||||
return;
|
||||
}
|
||||
|
||||
// Read data if needed.
|
||||
if((b->flags & B_WRITE) == 0 && ide_wait_ready(1) >= 0)
|
||||
insl(0x1f0, b->data, 512/4);
|
||||
|
||||
// Wake process waiting for this buf.
|
||||
b->done = 1;
|
||||
wakeup(b);
|
||||
|
||||
// Start disk on next buf in queue.
|
||||
if((ide_queue = b->qnext) != 0)
|
||||
ide_start_request(ide_queue);
|
||||
|
||||
release(&ide_lock);
|
||||
}
|
||||
|
||||
// Start the next request in the queue.
|
||||
// Caller must hold ide_lock.
|
||||
static void
|
||||
ide_start_request (void)
|
||||
{
|
||||
if(ide_queue){
|
||||
ide_wait_ready(0);
|
||||
outb(0x3f6, 0); // generate interrupt
|
||||
outb(0x1F2, 1); // number of sectors
|
||||
outb(0x1F3, ide_queue->sector & 0xFF);
|
||||
outb(0x1F4, (ide_queue->sector >> 8) & 0xFF);
|
||||
outb(0x1F5, (ide_queue->sector >> 16) & 0xFF);
|
||||
outb(0x1F6, 0xE0 |
|
||||
((ide_queue->dev & 1)<<4) |
|
||||
((ide_queue->sector>>24)&0x0F));
|
||||
if(ide_queue->flags & B_WRITE){
|
||||
outb(0x1F7, IDE_CMD_WRITE);
|
||||
outsl(0x1F0, ide_queue->data, 512/4);
|
||||
} else {
|
||||
outb(0x1F7, IDE_CMD_READ);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
//PAGEBREAK: 30
|
||||
// Queue up a disk operation and wait for it to finish.
|
||||
// b must have B_BUSY set.
|
||||
//PAGEBREAK!
|
||||
// Queue a disk operation and wait for it to finish.
|
||||
void
|
||||
ide_rw(struct buf *b)
|
||||
{
|
||||
struct buf **pp;
|
||||
|
||||
if((b->dev & 0xff) && !disk_1_present)
|
||||
if(!(b->flags & B_BUSY))
|
||||
panic("ide_rw: buf not busy");
|
||||
if(b->dev != 0 && !disk_1_present)
|
||||
panic("ide disk 1 not present");
|
||||
|
||||
acquire(&ide_lock);
|
||||
|
||||
// Append b to ide_queue.
|
||||
b->done = 0;
|
||||
b->qnext = 0;
|
||||
|
||||
// append b to ide_queue
|
||||
pp = &ide_queue;
|
||||
while(*pp)
|
||||
pp = &(*pp)->qnext;
|
||||
for(pp=&ide_queue; *pp; pp=&(*pp)->qnext)
|
||||
;
|
||||
*pp = b;
|
||||
|
||||
// Start disk if necessary.
|
||||
if(ide_queue == b)
|
||||
ide_start_request();
|
||||
ide_start_request(b);
|
||||
|
||||
// Wait for request to finish.
|
||||
while(!b->done)
|
||||
sleep(b, &ide_lock);
|
||||
|
||||
release(&ide_lock);
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue