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// MIT License, Copyright (c) 2020 Marvin Borner
#include <assert.h>
#include <cpu.h>
#include <def.h>
#include <fs.h>
#include <ide.h>
#include <mem.h>
#include <print.h>
PROTECTED static u8 *ide_buf = NULL;
struct ata_data {
u8 drive;
};
CLEAR static void ide_select_drive(u8 bus, u8 drive)
{
if (bus == ATA_PRIMARY) {
if (drive == ATA_MASTER)
outb(ATA_PRIMARY_IO + ATA_REG_HDDEVSEL, 0xa0);
else
outb(ATA_PRIMARY_IO + ATA_REG_HDDEVSEL, 0xb0);
} else {
if (drive == ATA_MASTER)
outb(ATA_SECONDARY_IO + ATA_REG_HDDEVSEL, 0xa0);
else
outb(ATA_SECONDARY_IO + ATA_REG_HDDEVSEL, 0xb0);
}
}
CLEAR static u8 ide_find(u8 bus, u8 drive)
{
u16 io = bus == ATA_PRIMARY ? ATA_PRIMARY_IO : ATA_SECONDARY_IO;
ide_select_drive(bus, drive);
// Reset
outb(io + ATA_REG_SECCOUNT0, 0);
outb(io + ATA_REG_LBA0, 0);
outb(io + ATA_REG_LBA1, 0);
outb(io + ATA_REG_LBA2, 0);
// Identify
outb(io + ATA_REG_COMMAND, ATA_CMD_IDENTIFY);
u8 status = inb(io + ATA_REG_STATUS);
if (!status)
return 0;
while ((inb(io + ATA_REG_STATUS) & ATA_SR_BSY) != 0)
;
do {
status = inb(io + ATA_REG_STATUS);
if (status & ATA_SR_ERR)
return 0;
} while ((status & ATA_SR_DRQ) == 0);
for (int i = 0; i < BLOCK_COUNT; i++)
*(u16 *)(ide_buf + i * 2) = inw(io + ATA_REG_DATA);
return 1;
}
static void ide_delay(u16 io) // 400ns
{
for (int i = 0; i < 4; i++)
inb(io + ATA_REG_ALTSTATUS);
}
static void ide_poll(u16 io)
{
for (int i = 0; i < 4; i++)
inb(io + ATA_REG_ALTSTATUS);
u8 status;
do {
status = inb(io + ATA_REG_STATUS);
} while (status & ATA_SR_BSY);
do {
status = inb(io + ATA_REG_STATUS);
assert(!(status & ATA_SR_ERR))
} while (!(status & ATA_SR_DRQ));
}
static u8 ata_read_one(u8 *buf, u32 lba, struct device *dev)
{
u8 drive = ((struct ata_data *)dev->data)->drive;
u16 io = (drive & ATA_PRIMARY << 1) == ATA_PRIMARY ? ATA_PRIMARY_IO : ATA_SECONDARY_IO;
drive = (drive & ATA_SLAVE) == ATA_SLAVE ? ATA_SLAVE : ATA_MASTER;
u8 cmd = drive == ATA_MASTER ? 0xe0 : 0xf0;
outb(io + ATA_REG_HDDEVSEL, (cmd | (u8)((lba >> 24 & 0x0f))));
outb(io + 1, 0x00);
outb(io + ATA_REG_SECCOUNT0, 1);
outb(io + ATA_REG_LBA0, (u8)lba);
outb(io + ATA_REG_LBA1, (u8)(lba >> 8));
outb(io + ATA_REG_LBA2, (u8)(lba >> 16));
outb(io + ATA_REG_COMMAND, ATA_CMD_READ_PIO);
ide_poll(io);
for (int i = 0; i < BLOCK_COUNT; i++) {
u16 data = inw(io + ATA_REG_DATA);
*(u16 *)(buf + i * 2) = data;
}
ide_delay(io);
return 1;
}
static res ata_read(void *buf, u32 lba, u32 sector_count, struct device *dev)
{
u8 *b = buf; // I love bytes, yk
for (u32 i = 0; i < sector_count; i++) {
ata_read_one(b, lba + i, dev);
b += SECTOR_SIZE;
}
return sector_count;
}
u8 ata_pm = 0, ata_ps = 0, ata_sm = 0, ata_ss = 0;
CLEAR static void ata_probe(void)
{
for (u8 i = 0; i < 4; i++) {
u32 bus = i < 2 ? ATA_PRIMARY : ATA_SECONDARY;
u32 drive = i % 2 ? ATA_MASTER : ATA_SLAVE;
if (!ide_find(bus, drive))
continue;
struct device *dev = zalloc(sizeof(*dev));
struct ata_data *data = malloc(sizeof(*data));
data->drive = (bus << 1) | drive;
char *str = malloc(40);
for (int j = 0; j < 40; j += 2) {
str[j] = ide_buf[ATA_IDENT_MODEL + j + 1];
str[j + 1] = ide_buf[ATA_IDENT_MODEL + j];
}
dev->name = str;
dev->type = DEV_BLOCK;
dev->read = ata_read;
device_add(dev);
if (vfs_mounted(dev, "/"))
continue;
// TODO: Check if ext2 first
struct vfs *vfs = zalloc(sizeof(*vfs));
vfs->type = VFS_EXT2;
vfs->read = ext2_read;
vfs->stat = ext2_stat;
vfs->perm = ext2_perm;
vfs->ready = ext2_ready;
dev->vfs = vfs;
dev->data = data;
vfs_mount(dev, "/");
}
}
CLEAR void ata_install(void)
{
ide_buf = zalloc(SECTOR_SIZE);
ata_probe();
}
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