Help in SATA device......

[East]

Hi all
I want to know the basics of SATA driver and how the sata devices are communicated to the driver> In PATA we have ports to access the devices.is there anything for SATA.As in a beginner stage can anyone help me?
Thanks in advance.

[East]

Can moderator redirect the thread to the correct forum topic?
Thanks.

[wje_lf]

Well, I think you're in the right church.

I googled, and found this. Does it help?

[East]

I have found site that tells about sending ATA commands to SATA device using sg ioctl. I have filled the sg structure with the below value.I am running this program in Fedora4

sg_io.interface_id = 'S';
sg_io.cmdp = cdb;
sg_io.cmd_len = sizeof(cdb);
sg_io.dxferp = data_in_buffer;
sg_io.dxfer_len = 512;//data_in_length; //
sg_io.dxfer_direction = SG_DXFER_FROM_DEV;
sg_io.sbp = sense;
sg_io.mx_sb_len = sizeof(sense);
sg_io.timeout = 15000;
and CDB structure is,
cdb[0] = 0x85; // ATA pass-through 12
cdb[1] = (4 << 1); // data-in
cdb[2] = 0x2e; // data-in
cdb[4] = 0x00; // ATA feature ID
cdb[6] = 1; // number of sector
cdb[7] = 0x00; //lba_low >> 8;
cdb[8] = 0x00; //lba_low;
cdb[9] = 0x00; //lba_mid >> 8;
cdb[10] = 0x00; //lba_mid;
cdb[11] = 0x00; //lba_high >> 8;
cdb[12] = 0x00; //lba_high;
cdb[14] = 0xEC; // ATA command ID
I have checked CDB values which i am passing with the document "ATA over scsi standard passthru implementation." I am creating the handle for /dev/sda. After passing the ioctl i am getting wrong values in sense buffer.
sense buffer[0]:0x70
sense buffer[1]:0x00
sense buffer[2]:0x05
sense buffer[3]:0x00
sense buffer[4]:0x00
sense buffer[5]:0x00
sense buffer[6]:0x00
sense buffer[7]:0x06
sense buffer[8]:0x00
sense buffer[9]:0x00
sense buffer[10]:0x00. As per program, these values are not valid. I dont know how they have defined like this. Can anyone help me regarding the sense buffer values.

[wje_lf]

I'm not ignoring you; unfortunately, I don't know the answer. I'm guessing that since nobody else has jumped in, nobody else here knows the answer here either. Sorry.