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#include "types.h"
#include "Task.h"
#include "IPC.h"
#include "VGA.h"
#include "Disk.h"
#include "kmalloc.h"
#include "StdLib.h"
#include "IO.h"
#include "i386.h"
#include "DataBuffer.h"
#include "PIC.h"
//#define DISK_DEBUG
extern "C" void handle_interrupt();
namespace Disk {
ide_drive_t drive[4];
static volatile bool interrupted;
#define IRQ_FIXED_DISK 14
extern "C" void ide_ISR();
asm(
".globl ide_ISR \n"
"ide_ISR: \n"
" pusha\n"
" pushw %ds\n"
" pushw %es\n"
" pushw %ss\n"
" pushw %ss\n"
" popw %ds\n"
" popw %es\n"
" call handle_interrupt\n"
" popw %es\n"
" popw %ds\n"
" popa\n"
" iret\n"
);
static void enableIRQ()
{
PIC::enable(IRQ_FIXED_DISK);
}
static void disableIRQ()
{
PIC::disable(IRQ_FIXED_DISK);
}
static bool waitForInterrupt()
{
#ifdef DISK_DEBUG
kprintf("disk: waiting for interrupt...\n");
#endif
// FIXME: Add timeout.
while (!interrupted) {
yield();
}
#ifdef DISK_DEBUG
kprintf("disk: got interrupt!\n");
#endif
return true;
}
void interrupt()
{
IRQHandlerScope scope(IRQ_FIXED_DISK);
#ifdef DISK_DEBUG
BYTE status = IO::in8(0x1f7);
kprintf("disk:interrupt: DRQ=%u BUSY=%u DRDY=%u\n", (status & DRQ) != 0, (status & BUSY) != 0, (status & DRDY) != 0);
#endif
interrupted = true;
}
void initialize()
{
disableIRQ();
interrupted = false;
registerInterruptHandler(IRQ_VECTOR_BASE + IRQ_FIXED_DISK, ide_ISR);
while (IO::in8(IDE0_STATUS) & BUSY);
IO::out8(0x1F6, 0xA0); // 0xB0 for 2nd device
IO::out8(IDE0_COMMAND, IDENTIFY_DRIVE);
enableIRQ();
waitForInterrupt();
RefPtr<DataBuffer> wbuf = DataBuffer::createUninitialized(512);
BYTE* byteBuffer = new BYTE[512];
BYTE* b = byteBuffer;
WORD* wbufbase = (WORD*)wbuf->data();
WORD* w = (WORD*)wbuf->data();
for (DWORD i = 0; i < 256; ++i) {
WORD data = IO::in16(IDE0_DATA);
*(w++) = data;
*(b++) = MSB(data);
*(b++) = LSB(data);
}
// "Unpad" the device name string.
for (DWORD i = 93; i > 54 && byteBuffer[i] == ' '; --i)
byteBuffer[i] = 0;
drive[0].cylinders = wbufbase[1];
drive[0].heads = wbufbase[3];
drive[0].sectors_per_track = wbufbase[6];
kprintf(
"ide0: Master=\"%s\", C/H/Spt=%u/%u/%u\n",
byteBuffer + 54,
drive[0].cylinders,
drive[0].heads,
drive[0].sectors_per_track
);
delete byteBuffer;
}
struct CHS {
DWORD cylinder;
WORD head;
WORD sector;
};
static CHS lba2chs(BYTE drive_index, DWORD lba)
{
ide_drive_t& d = drive[drive_index];
CHS chs;
chs.cylinder = lba / (d.sectors_per_track * d.heads);
chs.head = (lba / d.sectors_per_track) % d.heads;
chs.sector = (lba % d.sectors_per_track) + 1;
return chs;
}
bool readSectors(DWORD startSector, WORD count, BYTE* outbuf)
{
#ifdef DISK_DEBUG
kprintf("%s: Disk::readSectors request (%u sector(s) @ %u)\n",
current->name().characters(),
count,
startSector);
#endif
Task::checkSanity("Disk::readSectors");
disableIRQ();
CHS chs = lba2chs(IDE0_DISK0, startSector);
while (IO::in8(IDE0_STATUS) & BUSY);
#ifdef DISK_DEBUG
kprintf("ide0: Reading %u sector(s) @ LBA %u (%u/%u/%u)\n", count, startSector, chs.cylinder, chs.head, chs.sector);
#endif
IO::out8(0x1F2, count == 256 ? 0 : LSB(count));
IO::out8(0x1F3, chs.sector);
IO::out8(0x1F4, LSB(chs.cylinder));
IO::out8(0x1F5, MSB(chs.cylinder));
IO::out8(0x1F6, 0xA0 | chs.head); /* 0xB0 for 2nd device */
IO::out8(0x3F6, 0x08);
while (!(IO::in8(IDE0_STATUS) & DRDY));
IO::out8(IDE0_COMMAND, READ_SECTORS);
interrupted = false;
enableIRQ();
waitForInterrupt();
BYTE status = IO::in8(0x1f7);
if (status & DRQ) {
#ifdef DISK_DEBUG
kprintf("Retrieving %u bytes (status=%b), outbuf=%p...\n", count * 512, status, outbuf);
#endif
for (DWORD i = 0; i < (count * 512); i += 2) {
WORD w = IO::in16(IDE0_DATA);
outbuf[i] = LSB(w);
outbuf[i+1] = MSB(w);
}
}
return true;
}
}
extern "C" void handle_interrupt()
{
Disk::interrupt();
}
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