we can reaad CDROMS

2026-06-24 13:30:23 -05:00
parent ae4b6863bf
commit 68dbdbb2c8
7 changed files with 133 additions and 57 deletions
--- a/kernel/drivers/ide/ide.c
+++ b/kernel/drivers/ide/ide.c
@@ -0,0 +1,239 @@
+#include "ide.h"
+
+#include "lib/print.h"
+
+#include <stddef.h>
+#include <stdint.h>
+
+extern uint8_t inb(uint16_t port);
+extern void outb(uint16_t port, uint8_t data);
+
+extern void insw(uint32_t address, void* buf, uint32_t sz);
+extern void outsw(uint32_t address, void* buf, uint32_t sz);
+
+uint8_t selected_drive_primary = 0;
+uint8_t selected_drive_secondary = 0;
+
+uint8_t ide_info_buffer[512];
+
+ide_device_t ide_devices[4];
+
+static void fix_ata_string(char* buf, size_t sz) {
+    if ((sz % 2) != 0) return;
+    for (size_t i = 0; i < sz; i += 2) {
+        char tmp = buf[i];
+        buf[i] = buf[i + 1];
+        buf[i + 1] = tmp;
+    }
+    buf[sz-1] = '\0'; 
+}
+
+static uint16_t fetch_ctrl_reg(uint16_t bus) {
+    if (bus == IDE_PRIMARY_IO_BASE) return IDE_PRIMARY_CRTL_BASE;
+    if (bus == IDE_SECONDARY_IO_BASE) return IDE_SECONDARY_CRTL_BASE;
+    return 0;
+}   
+
+static void ata_delay(uint16_t bus) {
+    uint16_t ctrl = fetch_ctrl_reg(bus);
+    for (int i = 0; i < 5; i++) {
+        inb(ctrl);
+    }
+}
+
+static int wait_not_bsy_drq(uint16_t bus) {
+    ata_delay(bus);
+
+    int timeout = 10000;
+    int error = 0;
+    while(timeout--) {
+        uint16_t ctrl = fetch_ctrl_reg(bus);
+        uint8_t stat = inb(ctrl);
+        if (stat & STATUS_REG_ERR) error = 1; break;
+        if (!(stat & STATUS_REG_BSY)) break;
+    }
+
+    if (timeout == 0 || error) {
+        return 1;
+    }
+
+    return 0;
+}
+
+static int select_drive(uint16_t bus, uint8_t drive) {
+    if (bus == IDE_PRIMARY_IO_BASE && selected_drive_primary == drive) {
+        return 1;
+    }
+
+    if (bus == IDE_SECONDARY_IO_BASE && selected_drive_secondary == drive) {
+        return 1;
+    }
+
+    uint16_t ctrl_reg = fetch_ctrl_reg(bus);
+    if (ctrl_reg == 0) {
+        return 0;
+    }
+
+    // wait for bsy and drq clear
+    while (1) {
+        uint8_t status = inb(ctrl_reg + CTRL_ALT_STATUS_REG);
+        if (!(status & STATUS_REG_BSY) && !(status & STATUS_REG_DRQ)) {
+            break;
+        }
+    }
+
+    outb(bus + IO_DRIVE_SELECT_REG, drive);
+
+    ata_delay(bus);
+
+    uint8_t status = inb(ctrl_reg + CTRL_ALT_STATUS_REG);
+    if (status & STATUS_REG_ERR) {
+        return 0;
+    }
+
+    return 1;
+}
+
+static void ident_device(uint16_t bus, uint8_t drive, uint32_t slot) {
+    ide_dev_type type = NO_DEVICE;
+
+    uint8_t stat = inb(bus + IO_STATUS_REG);
+    if (stat == 0xFF) {
+        kprintf("no device on bus 0x%x\n", bus);
+        return;
+    }
+
+    if (!select_drive(bus, drive)) {
+        kprintf("failed to select drive 0x%x on bus 0x%x\n", bus, drive);
+        return;
+    }
+
+    outb(bus + IO_SECTOR_COUNT_REG, 0x00);
+    outb(bus + IO_LBA_LO_REG, 0x00);
+    outb(bus + IO_LBA_MID_REG, 0x00);
+    outb(bus + IO_LBA_HI_REG, 0x00);
+    // ident ata
+    outb(bus + IO_CMD_REG, ATA_CMD_IDENTIFY);
+    ata_delay(bus);
+
+    stat = inb(bus + IO_STATUS_REG);
+    if (stat == 0x00) {
+        kprintf("no drive 0x%x on bus 0x%x\n", drive, bus);
+        return;
+    }
+
+    int not_ata = 0;
+    int timeout = 10000;
+    while(timeout--) {
+        stat = inb(bus + IO_STATUS_REG);
+        if (stat & STATUS_REG_ERR) not_ata = 1; break;
+        if (!(stat & STATUS_REG_BSY) && (stat & STATUS_REG_DRQ)) type = ATA; break;
+    }
+
+    if (timeout == 0) {
+        kprintf("drive 0x%x ident timed out on bus 0x%x\n", drive, bus);
+        return;
+    }
+
+    if (not_ata) {
+        uint8_t mid = inb(bus + IO_LBA_MID_REG);
+        uint8_t hi = inb(bus + IO_LBA_HI_REG);
+
+        if (mid != 0x14 || hi != 0xEB) {
+            return;
+        }
+
+        type = ATAPI;
+
+        // ident atapi
+        outb(bus + IO_CMD_REG, ATA_CMD_IDENTIFY_PACKET);
+        ata_delay(bus);
+    }
+
+    
+    insw(bus + IO_DATA_REG, ide_info_buffer, 256);
+
+    ide_devices[slot].bus = bus;
+    ide_devices[slot].device = drive;
+    ide_devices[slot].type = type;
+    ide_devices[slot].capabilities = *(uint16_t*)(ide_info_buffer + ATA_IDENT_CAPABILITIES);
+    ide_devices[slot].sig = *(uint16_t*)(ide_info_buffer + ATA_IDENT_DEVICETYPE);
+    ide_devices[slot].command_set = *(uint32_t*)(ide_info_buffer + ATA_IDENT_COMMANDSETS);
+
+    if (ide_devices[slot].command_set & (1 << 26)) {
+        ide_devices[slot].size = *(uint32_t*)(ide_info_buffer + ATA_IDENT_MAX_LBA_EXT);
+    } else {
+        ide_devices[slot].size = *(uint32_t*)(ide_info_buffer + ATA_IDENT_MAX_LBA);
+    }
+}
+
+static int atapi_read_sector(ide_device_t* dev, uint32_t lba, uint32_t sectors, void* buf) {
+    ide_device_t drive = *dev;
+
+    // enable irqs
+    uint16_t ctrl_reg = fetch_ctrl_reg(drive.bus);
+    outb(ctrl_reg, 0x00);
+
+    uint8_t pkt[12];
+    pkt[ 0] = ATAPI_CMD_READ;
+    pkt[ 1] = 0x0;
+    pkt[ 2] = (lba >> 24) & 0xFF;
+    pkt[ 3] = (lba >> 16) & 0xFF;
+    pkt[ 4] = (lba >> 8) & 0xFF;
+    pkt[ 5] = (lba >> 0) & 0xFF;
+    pkt[ 6] = 0x0;
+    pkt[ 7] = 0x0;
+    pkt[ 8] = 0x0;
+    pkt[ 9] = sectors;
+    pkt[10] = 0x0;
+    pkt[11] = 0x0;
+
+    if (!select_drive(drive.bus, drive.device)) {
+        return 0;
+    }
+
+    outb(drive.bus + IO_FEATURE_REG, 0x00); // PIO mode
+
+    uint32_t words = 1024;
+    outb(drive.bus + IO_LBA_MID_REG, (words * 2) & 0xFF);
+    outb(drive.bus + IO_LBA_HI_REG, (words * 2) >> 8);
+
+    outb(drive.bus + IO_CMD_REG, ATA_CMD_PACKET);
+    
+    // poll for drq
+    int err = wait_not_bsy_drq(drive.bus);
+    if (err) {
+        return 0;
+    }
+
+    outsw(drive.bus + IO_DATA_REG, pkt, 6);
+
+    uint32_t ptr = (uint32_t)buf;
+    for (int i = 0; i < sectors; i++) {
+        err = wait_not_bsy_drq(drive.bus);
+        if (err) {
+            return 0;
+        }
+        
+        insw(drive.bus + IO_DATA_REG, (void*)ptr, 1024);
+        ptr += 2048;    
+    }
+
+    return 1;
+}
+
+void scan_drives() {
+    ident_device(IDE_SECONDARY_IO_BASE, IDE_DRIVE_MASTER, 0);
+}
+
+ide_device_t* get_device(uint8_t slot) {
+    if (slot > 3) return NULL;
+    return &ide_devices[slot];
+}
+
+int ide_read_blks(ide_device_t* dev, uint32_t lba, uint32_t sectors, void* buf) {
+    if (dev->type == ATAPI) {
+        return atapi_read_sector(dev, lba, sectors, buf);
+    }
+    return 0;
+}
--- a/kernel/drivers/ide/ide.h
+++ b/kernel/drivers/ide/ide.h
@@ -0,0 +1,123 @@
+#ifndef KATA_H
+#define KATA_H
+
+#ifndef __ASSEMBLER__
+#include <stdint.h>
+#include <stddef.h>
+#endif
+
+#define IDE_PRIMARY_IO_BASE 0x01F0
+#define IDE_PRIMARY_CRTL_BASE 0x03F6
+
+#define IDE_SECONDARY_IO_BASE 0x0170
+#define IDE_SECONDARY_CRTL_BASE 0x0376
+
+#define IDE_DRIVE_MASTER 0xA0
+#define IDE_DRIVE_SLAVE 0xB0
+
+#define IO_DATA_REG 0x0000
+#define IO_ERROR_REG 0x0001
+#define IO_FEATURE_REG 0x0001
+#define IO_SECTOR_COUNT_REG 0x0002
+#define IO_SECTOR_NUM_REG 0x0003 
+#define IO_LBA_LO_REG 0x0003
+#define IO_CYL_LO_REG 0x0004
+#define IO_LBA_MID_REG 0x0004
+#define IO_LBA_HI_REG 0x0005
+#define IO_CYL_HI_REG 0x0005
+#define IO_DRIVE_SELECT_REG 0x0006
+#define IO_STATUS_REG 0x0007
+#define IO_CMD_REG 0x0007
+
+#define CTRL_ALT_STATUS_REG 0x00
+#define CTRL_DEV_CTRL_REG 0x00
+#define CTRL_DRIVE_ADDR_REG 0x01
+
+#define ERROR_REG_AMNF  0b00000001  // Address mark not found
+#define ERROR_REG_TKZNF 0b00000010  // Track zero not found
+#define ERROR_REG_ABRT  0b00000100  // Aborted command
+#define ERROR_REG_MCR   0b00001000  // Media change request
+#define ERROR_REG_IDNF  0b00010000  // ID not found
+#define ERROR_REG_MC    0b00100000  // Media changed
+#define ERROR_REG_UNC   0b01000000  // Uncorrectable data error
+#define ERROR_REG_BBK   0b10000000  // Bad Block detected
+
+#define DRIVE_SELECT_REG_BN     0b00000111
+#define DRIVE_SELECT_REG_DRV    0b00010000
+#define DRIVE_SELECT_REG_LBA   0b01000000
+
+#define STATUS_REG_ERR  0b00000001
+#define STATUS_REG_IDX  0b00000010
+#define STATUS_REG_CORR 0b00000100
+#define STATUS_REG_DRQ  0b00001000
+#define STATUS_REG_SRV  0b00010000
+#define STATUS_REG_DF   0b00100000
+#define STATUS_REG_RDY  0b01000000
+#define STATUS_REG_BSY  0b10000000
+
+#define DEV_CTRL_REG_nIEN   0b00000010
+#define DEV_CTRL_REG_SRST   0b00000100
+#define DEV_CTRL_REG_HOB    0b10000000
+
+#define DRIVE_ADDR_REG_DS0      0b00000001
+#define DRIVE_ADDR_REG_DS1      0b00000010
+#define DRIVE_ADDR_REG_HEAD     0b00111100
+#define DRIVE_ADDR_REG_WTG      0b01000000
+
+#define ATA_CMD_READ_PIO          0x20
+#define ATA_CMD_READ_PIO_EXT      0x24
+#define ATA_CMD_READ_DMA          0xC8
+#define ATA_CMD_READ_DMA_EXT      0x25
+#define ATA_CMD_WRITE_PIO         0x30
+#define ATA_CMD_WRITE_PIO_EXT     0x34
+#define ATA_CMD_WRITE_DMA         0xCA
+#define ATA_CMD_WRITE_DMA_EXT     0x35
+#define ATA_CMD_CACHE_FLUSH       0xE7
+#define ATA_CMD_CACHE_FLUSH_EXT   0xEA
+#define ATA_CMD_PACKET            0xA0
+#define ATA_CMD_IDENTIFY_PACKET   0xA1
+#define ATA_CMD_IDENTIFY          0xEC
+
+#define ATAPI_CMD_READ       0xA8
+#define ATAPI_CMD_EJECT      0x1B
+
+#define ATA_IDENT_DEVICETYPE   0
+#define ATA_IDENT_CYLINDERS    2
+#define ATA_IDENT_HEADS        6
+#define ATA_IDENT_SECTORS      12
+#define ATA_IDENT_SERIAL       20
+#define ATA_IDENT_MODEL        54
+#define ATA_IDENT_MODEL_SZ     40
+#define ATA_IDENT_CAPABILITIES 98
+#define ATA_IDENT_FIELDVALID   106
+#define ATA_IDENT_MAX_LBA      120
+#define ATA_IDENT_COMMANDSETS  164
+#define ATA_IDENT_MAX_LBA_EXT  200
+
+#ifndef __ASSEMBLER__
+typedef enum {
+    NO_DEVICE = 0,
+    ATA,
+    ATAPI,
+} ide_dev_type;
+
+
+typedef struct __attribute__((packed)) {
+    uint16_t bus;
+    uint8_t device;
+    ide_dev_type type;
+    uint16_t sig;
+    uint16_t capabilities;
+    uint32_t command_set;
+    char* serial;
+    char* model;
+    uint32_t size;
+} ide_device_t;
+
+void scan_drives();
+ide_device_t* get_device(uint8_t slot);
+int ide_read_blks(ide_device_t* dev, uint32_t lba, uint32_t sectors, void* buf);
+
+#endif
+
+#endif