atadrv.c

vxworks硬盘DMA驱动,VXWORKS 6.0以前版本不支持ATA硬盘的DMA传输方式,只支持PIO模式,假如该驱动后,可能会极大提高传输速度,快下吧!

/* ataDrv.c - ATA/IDE and ATAPI CDROM (LOCAL and PCMCIA) disk device driver */

/*
 * Copyright (c) 1989-2005 Wind River Systems, Inc.
 *
 * The right to copy, distribute, modify or otherwise make use
 * of this software may be licensed only pursuant to the terms
 * of an applicable Wind River license agreement.
 */

/*
modification history
--------------------
02j,13oct05,dee  SPR# 113433, better error handling for non-existent ATA
                 drives
02i,12oct05,dee  Fix SPR#113365, detect removable device on first insertion;
		 SPR#113108, cleanup gnu compiler warnings
02h,19sep05,dee  Fix SPR#112529, change all ERF events to ASYNC
02g,07sep05,dee  SPR#111796 fix ioctl handling when checking for media present
02f,01sep05,pcm  fixed documentation
02e,08aug05,dee  Change to XBD (extended block device) interface.
02d,29jul05,dee  checkin new dma version ATAPI-5
02c,24may05,dee  fix SPR#102006, pccard ata disk, cleanup copyright
02b,07sep04,jyo  Fixing SPR 100119: Removing references to RT11.
02a,18feb04,rfr  Added ioctl FIOSYNC
01i,22feb02,rip  api change for ModeNegotiate (to take into account chan,drv)
                 Also merged in changes from smz wrt cdrom multimedia
01h,01feb02,ero  changed the name of the function ataDrv to ataPiDrv
01g,01feb02,taw  Bug Fix
01f,31jan02,smz  removed hardware depencies.
01e,24jan02,bsp  bug fixed in determining best multi DMA mode if supported.
01d,15jan02,bsp  memory initialization for packet command functions done  
01c,11jan02,bsp  some of function names changed as WRCC rule
01b,20dec01,bsp  standardized as per WRCC and some functions moved from/to 
                 atapiLib.c to differentiate from low level function to 
                 high level ( with respective to functionality).
01a,21Nov01,bsp  written.
*/

/*
DESCRIPTION:
\sh BLOCK DEVICE DRIVER:
This is a Block Device Driver for ATA/ATAPI devices on IDE host controller. 
It also provides neccessary functions to user for device and its features 
control which are not used or utilized by file system. 

This driver provides standard Block Device Driver functions,(blkRd, blkWrt, 
ioctl, statusChk, and reset) for ATA and ATAPI devices separately as the 
scheme of implementation differs. These functions are implemented as 
ataBlkRd(), ataBlkWrt(), ataBlkIoctl(), ataStatus() and ataReset() for ATA
devices and atapiBlkRd(), atapiBlkWrt(), atapiBlkIoctl(), atapiStatusChk() 
and atapiReset() for ATAPI devices. The Block Device Structure BLK_DEV is
updated with these function pointers ata initialization of the driver 
depending on the type of the device in function ataDevCreate().

ataDrv(), a user callable function, initializes ATA/ATAPI devices present on
the specified IDE controller(either primary or secondary), which must be called
once for each controller, before usage of this driver, usally called from
usrRoot()in usrConfig.c. 

The routine ataDevCreate(), which is user callable function, is used to mount
a logical drive on an ATAPI drive.This routine returns a pointer to BLK_DEV 
structure, which is used to mount the file system on the logical drive.

\sh OTHER NECESSARY FUNCTIONS FOR USER:

There are various functions provided to user, which can be classified to 
different catagories as device contol function, device information functions 
and functions meant for packet devices.

Device Control Function:

atapiIoctl() function is used to control a device. Block Device Driver functions 
ataBlkIoctl() and atapiBlkIcotl()functions are also routed to this function. 
This function implements various control command functions which are not used 
by the I/O system (like power managment feature set commands, host protected 
feature set commands, security feature set commands, media control functions 
etc).

Device Information Function:

In this catagory various functions are implmented depending on the information 
required. These functions return information required ( like cylinder count, 
Head count, device serial number, device Type, etc)from the internal device 
structures.

Packet Command Functions:

Although Block Device Driver functions deliver packet commands using functions 
provided by atapiLib.c for required functionality. There are group of functions 
provided in this driver to user for ATAPI device, which implements packet 
commands for 'CD_ROM' that comply to 'ATAPI-SFF8020i' specification which are 
essentially required for CD ROM operation for file system.  These 
functions are named after their command name (like for REQUEST SENSE packet 
command atapiReqSense() function).  To issue other packet commands 
atapiPktCmdSend() can be used.

This driver also provides a generic function atapiPktCmdSend() to issue a 
packet command to ATAPI devices, which can be utilized by user to issue packet
command directly instead using the implmented functions also may be used to 
send new commands ( may come in later specs) to device. User can issue any 
packet command using atapiPktCmdSend() function to the required device by 
passing its BLK_DEV structure pointer and pointer for ATAPI_CMD command packet.

typedef of ATAPI_CMD

.CS
    typedef struct atapi_cmd
        {
        UINT8          cmdPkt [ATAPI_MAX_CMD_LENGTH];
        char           **ppBuf;
        UINT32         bufLength;
        ATA_DATA_DIR   direction;
        UINT32         desiredTransferSize;
        BOOL           dma;
        BOOL           overlap;
        } ATAPI_CMD;
.CE

and ATA_DATA_DIR typedef is 

.CS
typedef enum  /@ with respect to host/memory @/
    {
    NON_DATA, /@ non data command     @/
    OUT_DATA, /@ to drive from memory @/
    IN_DATA   /@ from drive to memory @/
    } ATA_DATA_DIR;
.CE

User is expected supposed to fill the ATAPI_CMD structure with required 
parameters of the packet and pass the ATAPI_CMD structure pointer to  
atapiPktCmdSend() fuuction for command execution.  

All the packet command functions require ATA_DEV structure to be passed, which 
alternatively a BLK_DEV Device Structure of the device. One should type convert 
the structure and the same BLK_DEV structrue pointer to these functions.

The routine ataPiRawio() supports physical I/O access. The first
argument is the controller number, 0 or 1; the second argument is drive
number, 0 or 1; the third argument is a pointer to an ATA_RAW structure.

\sh PARAMETERS:
The ataPiDrv() function requires a configuration flag as a parameter.
The configuration flag is one of the following or Bitwise OR of any of the
following combination:

configuration flag =
    Transfer mode | Transfer bits | Transfer unit | Geometry parameters

.TS
tab(|);
l l l.
Transfer mode       | Description                   |  Transfer Rate

ATA_PIO_DEF_0       | PIO default mode              |
ATA_PIO_DEF_1       | PIO default mode, no IORDY    |
ATA_PIO_0           | PIO mode 0                    |     3.3 MBps
ATA_PIO_1           | PIO mode 1                    |     5.2 MBps
ATA_PIO_2           | PIO mode 2                    |     8.3 MBps
ATA_PIO_3           | PIO mode 3                    |    11.1 MBps
ATA_PIO_4           | PIO mode 4                    |    16.6 MBps
ATA_PIO_AUTO        | PIO max supported mode        |
ATA_DMA_SINGLE_0    | Single DMA mode 0             |     2.1 MBps
ATA_DMA_SINGLE_1    | Single DMA mode 1             |     4.2 MBps
ATA_DMA_SINGLE_2    | Single DMA mode 2             |     8.3 MBps
ATA_DMA_MULTI_0     | Multi word DMA mode 0         |     4.2 MBps
ATA_DMA_MULTI_1     | Multi word DMA mode 1         |    13.3 MBps
ATA_DMA_MULTI_2     | Multi word DMA mode 2         |    16.6 MBps
ATA_DMA_ULTRA_0     | Ultra DMA mode 0              |    16.6 MBps
ATA_DMA_ULTRA_1     | Ultra DMA mode 1              |    25.0 MBps
ATA_DMA_ULTRA_2     | Ultra DMA mode 2              |    33.3 MBps
ATA_DMA_ULTRA_3     | Ultra DMA mode 3              |    44.4 MBps
ATA_DMA_ULTRA_4     | Ultra DMA mode 4              |    66.6 MBps
ATA_DMA_ULTRA_5     | Ultra DMA mode 5              |   100.0 MBps
ATA_DMA_AUTO        | DMA max supported mode        |

Transfer bits

ATA_BITS_16      | RW bits size, 16 bits
ATA_BITS_32      | RW bits size, 32 bits

Transfer unit

ATA_PIO_SINGLE   | RW PIO single sector
ATA_PIO_MULTI    | RW PIO multi sector

Geometry parameters

ATA_GEO_FORCE    | set geometry in the table
ATA_GEO_PHYSICAL | set physical geometry
ATA_GEO_CURRENT  | set current geometry
.TE

ISA SingleWord DMA mode is obsolete in ata-3.

The Transfer rates shown above are the Burst transfer rates.
If ATA_PIO_AUTO is specified, the driver automatically chooses the maximum
PIO mode supported by the device. If ATA_DMA_AUTO is specified, the driver
automatically chooses the maximum Ultra DMA mode supported by the device and if
the device doesn't support the Ultra DMA mode of data transfer, the driver
chooses the best Multi Word DMA mode. If the device doesn't support the
multiword DMA mode, driver chooses the best single word DMA mode. If the device
doesn't support DMA mode, driver automatically chooses the best PIO mode.
So it is recommended to specify the ATA_DMA_AUTO.

If ATA_PIO_MULTI is specified, and the device does not support it, the driver
automatically chooses single sector or word mode. If ATA_BITS_32 is specified,
the driver uses 32-bit transfer mode regardless of the capability of the drive.
The Single word DMA mode will not be supported by the devices compliant to
ATA/ATAPI-5 or higher.

This driver supports UDMA mode data transfer from device to host, provided 80 
conductor cable is used for required controller device. This check done at the 
initilisation of the device from the device parameters and if 80 conductor
cable is connected then UDMA mode transfer is selected for operation subject to 
condition that required UDMA mode is supported by device as well as host. 
This driver follows ref-3 Chapter 4 "Determining a Drive's Transfer Rate 
Capability" to determine drives best transfer rate for all modes ( ie UDMA, 
MDMA, SDMA and PIO modes).

The host IDE Bus master functions are to be mapped to follwing macro defined 
for various functionality in header file which are used in this driver. 

'ATA_HOST_CTRL_INIT'          - initialize the controller

'ATA_HOST_DMA_ENGINE_INIT'    - initialize bus master DMA engine  

'ATA_HOST_DMA_ENGINE_START'   - Start bus master operation

'ATA_HOST_DMA_ENGINE_STOP'    - Stop bus master operation

'ATA_HOST_DMA_TRANSFER_CHK'   - check bus master data transfer complete

'ATA_HOST_DMA_MODE_NEGOTIATE' - get mode supported by controller

'ATA_HOST_SET_DMA_RWMODE'     - set controller to required mode

'ATA_HOST_CTRL_RESET'         - reset the controller  

If ATA_GEO_PHYSICAL is specified, the driver uses the physical geometry
parameters stored in the drive.  If ATA_GEO_CURRENT is specified,
the driver uses current geometry parameters initialized by BIOS.
If ATA_GEO_FORCE is specified, the driver uses geometry parameters stored
in sysLib.c.

The geometry parameters are stored in the structure table
`ataTypes[]' in sysLib.c. That table has two entries, the first for
drive 0, the second for drive 1. The members of the structure are:
.CS
    int cylinders;              /@ number of cylinders @/
    int heads;                  /@ number of heads @/
    int sectors;                /@ number of sectors per track @/
    int bytes;                  /@ number of bytes per sector @/
    int precomp;                /@ precompensation cylinder @/
.CE


The driver supports two controllers and two drives on each. This is dependent 
on the configuration parameters supplied to ataPiDrv().

References:
    1) ATAPI-5 specification "T13-1321D Revision 1b, 7 July 1999"
    2) ATAPI for CD-ROMs "SFF-8020i Revision 2.6, Jan 22,1996"
    3) Intel