PIO read sometimes dont work

[Klakap]

Good day!

I have strange problem. My PIO driver sometimes read values and sometimes not.

Code: Select all

int ata_pio28(uint16_t base, uint8_t type, uint64_t addr) {
    int cycle=0;

    //PIO28
    outb(base+ATA_PORT_FEATURES, 0x00);
    outb(base+ATA_PORT_SCT_COUNT, 0x01);
    outb(base+ATA_PORT_SCT_NUMBER, (unsigned char)addr);
    outb(base+ATA_PORT_CYL_LOW, (unsigned char)(addr >> 8));
    outb(base+ATA_PORT_CYL_HIGH, (unsigned char)(addr >> 16));
    //type
    if(type==ATA_READ) {
    outb(base+ATA_PORT_COMMAND, 0x20);  // Send command
    }
    else {
    outb(base+ATA_PORT_COMMAND, 0x30);
    }

    //wait for BSY clear and DRQ set
    cycle=0;
    for(int i=0; i<1000; i++) {
        inb(base+ATA_PORT_ALT_STATUS);  //wait
        if( (inb(base+ATA_PORT_ALT_STATUS) & 0x88)==0x08 ) {  //drq is set
            cycle=1;
            break;    
        }    
    }
    if(cycle==0) {  //Something is wrong
        if( (inb(base+ATA_PORT_ALT_STATUS) & 0x01)==0x01 ) {  //bad block
            system_ata_pio_error();    
        } 
        return 0;
    }

    if( (inb(base+ATA_PORT_ALT_STATUS) & 0x01)==0x01 ) {  //bad block
        system_ata_pio_error();    
    }

    for (int idx = 0; idx < 256; idx++)
    {
        if(type==ATA_READ) {
            ata_buffer[idx] = inw(base + ATA_PORT_DATA);
        }
        else {
            outw(base + ATA_PORT_DATA, ata_buffer[idx]);
        }
    }

    return 1;
}

And I am acknowledging irq:

Code: Select all

void irq14_handler(void) {
          outb(0xA0, 0x20);
          outb(0x20, 0x20); //EOI

          //acknowledge interrupt
          inb(0x1F7);
}

Please, what is wrong? Or is error here?