Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Mon, 27 Mar 2000 15:28:14 -0600

Geoff Savage wrote:
> 
> After searching through the archives it appears that I need to modify my
> mv162lx BSP to handle A24 DMA correctly.  Has someone already made this
> modification?  Can I get a copy?  Are any changes to the driver
> (drvGpib.c) necessary?

Geoff,

the following routines are from the sysLib.c of my latest mv162 BSP in use
here at APS. I haven't looked at all the changes I made, but hopefully you
should get the idea and be able to use most of this code as is.  You'll
also have to modify sysProcNumSet() to disable the A24 VME window [clear
the VSAMSR2 bits of VMECHIP2_VSAMSR - the A24 window is set up later in
sysA24MapRam()], and change the A24 part of sysLocalToBusAdrs() as shown. 
You shouldn't need to change anything in the NI-1014 gpib driver, which
uses devLib routines that call sysA24Malloc() if it is present.

None of the code below was written by Wind River Systems.

- Andrew
-- 
Complexity comes for free, Simplicity you have to work for.

---- from sysLocalToBusAdrs: ------------------------------------------

        case VME_AM_STD_SUP_PGM:
        case VME_AM_STD_SUP_DATA:
        case VME_AM_STD_USR_PGM:
        case VME_AM_STD_USR_DATA:
            if (*VMECHIP2_VSAMSR & VSAMSR2_A24)
	        {
        	ULONG vsatr = *VMECHIP2_VSATR2;
		ULONG vsar  = *VMECHIP2_VSAR2;
		ULONG adrs = vsatr & (vsatr << 16);
		if (((ULONG)localAdrs < adrs) ||
		    ((ULONG)localAdrs > adrs + (vsar | 0x0000ffff)))
		    return (ERROR);
		adrs = (ULONG)localAdrs - adrs + ((vsar & 0xffff) << 16);
		*pBusAdrs = (char *)adrs;
		return (OK);
		}
	    return (ERROR);

---- other routines: -------------------------------------------------

/*******************************************************************************
*
* sysVmeMapShow - report mappings between VMEbus and local memory
*
* This routine displays the mapping between VMEbus and local memory 
* locations in both directions.
*
* RETURNS: OK
*
* NOMANUAL
*/

STATUS sysVmeMapShow(void)
    {
    unsigned int local, vme, size;

    printf("\nVMEbus viewed from CPU:\n");
    vme  = *VMECHIP2_LBSAR1 << 16;
    if (vme < 0x80000000) vme = 0x80000000;	/* dtt1 setting */
    size = *VMECHIP2_LBSAR1 | 0x0000ffff;
    printf("  CPU:\t0x%8.8X - 0x%8.8X  =>  A32: 0x%8.8X - 0x%8.8X\n",
	   vme, size, vme, size);
    printf("\t0xF0000000 - 0xF0FFFFFF  =>  A24:   0x000000 -  
0xFFFFFF\n");
    printf("\t0xFFFF0000 - 0xFFFFFFFF  =>  A16:     0x0000 -    
0xFFFF\n");

    printf("\nCPU viewed from VMEbus:\n");
    if (*VMECHIP2_VSAMSR & VSAMSR1_A32)
	{
	local = *VMECHIP2_VSATR1 & (*VMECHIP2_VSATR1 << 16);
	vme   = *VMECHIP2_VSAR1 << 16;
	size  = (*VMECHIP2_VSAR1 | 0x0000ffff) - vme;
	printf("  A32:\t0x%8.8X - 0x%8.8X  =>  CPU: 0x%8.8X - 0x%8.8X\n",
		vme, vme + size, local, local + size);
	}
    else
	printf("  A32:\t           -             =>                  -\n");

    if (*VMECHIP2_VSAMSR & VSAMSR2_A24)
	{
	local = *VMECHIP2_VSATR2 & (*VMECHIP2_VSATR2 << 16);
	vme   = *VMECHIP2_VSAR2 << 16;
	size  = (*VMECHIP2_VSAR2 | 0x0000ffff) - vme;
	printf("  A24:\t  0x%6.6X -   0x%6.6X  =>       0x%8.8X - 0x%8.8X\n",
		vme, vme + size, local, local + size);
	}
    else
	printf("  A24:\t           -             =>                  -\n");

    vme = (unsigned) (*VMECHIP2_LBTVCR >> 16) & 0xfff0;
    if ((vme & 0x00f0) != 0xf0)
	{
	printf("  A16:\t    0x%4.4X -     0x%4.4X  =>       Global Ctrl Status
Regs\n",
		vme, vme + 0x000f);
	}
    else
	printf("  A16:\t           -             =>                  -\n");

    return OK;
    }

#define MEM_PART_OVERHEAD 64
LOCAL PART_ID a24MemPartId;		/* VME A24 memory partition */

/*******************************************************************************
*
* sysA24MapRam - reserve memory for A24 DMA use
*
* Some VME Bus Master cards are not able to generate extended VME (A32) 
* addresses, thus the CPU board must export some of its memory in the
* standard (A24) address space.  This routine allows application software
* to specify a minimum size of memory to be reserved for use with such
* devices.  If successful, memory is subsequently obtained from the memory
* partition by calling sysA24Malloc() and returned with sysA24Free().
*
* If this routine is not called, the first use of sysA24Malloc() will
* cause a default minimum size of partition to be created, currently set
* to 64 Kbytes.  Requests are clipped to 8Mbytes to ensure that there will
* always be room in the A24 address space for I/O cards.
*
* RETURNS: OK, or ERROR if the partition has already been created or
* insufficient free memory is available to fulfil the request.
*
* SEE ALSO: sysA24Malloc(), sysA24Free()
*/

STATUS sysA24MapRam
    (
    unsigned long size		/* Minimum partition size */
    )
    {
    int mask;
    int bsize;
    char *mem;

    if (sysProcNumGet() != 0)
	return ERROR;
    if (a24MemPartId != NULL)
	return ERROR;

    if (size > 0x800000)
	{
	size  = 0x800000;
	bsize = size;
	mask  = 0xff80;
	}
    else if (size < 0x010000)
	{
	size  = 0x10000;
	bsize = size;
	mask  = 0xffff;
	}
    else
	{
	/* Work out the correct window size and mask */
	bsize = 0x400000;
	mask  = 0xffffc0;
	while (bsize > size)
	    {
	    bsize >>= 1;
	    mask  >>= 1;
	    }
	if (bsize != size)
	    {
	    bsize <<= 1;
	    mask  <<= 1;
	    }
	mask &= 0xffff;
	}

    /* Check alignment against A24 base address */
    if ((LOCAL_MEM_BUS_A24 >> 16) & ~mask)
	return ERROR;

    /* Create the memory pool aligned on a bsize boundary */
    mem = memalign(bsize, size); /* cacheDmaMalloc??? */
    if (mem == NULL) return ERROR;
    a24MemPartId = memPartCreate(mem, size);
    if (a24MemPartId == NULL)
	{
	free(mem);
	return ERROR;
	}

    *VMECHIP2_VSAR2   = (LOCAL_MEM_BUS_A24 >> 16) |
			((LOCAL_MEM_BUS_A24 + bsize - 1) & 0xffff0000);
    *VMECHIP2_VSATR2  = (int)mem | mask;
    *VMECHIP2_VSAMSR |= (VSAMSR2_SNP_WSD |
			 VSAMSR2_WP	|
			 VSAMSR2_SUP	|
			 VSAMSR2_USR	|
			 VSAMSR2_A24	|
			 VSAMSR2_D64	|
			 VSAMSR2_BLK	|
			 VSAMSR2_PGM	|
			 VSAMSR2_DAT);	/* all but A32 */
    return OK;
    }

/*******************************************************************************
*
* sysA24Malloc - allocate a memory block from the A24 partition
*
* This routine allocates a block of memory for use by VME devices that
* can only perform DMA in the standard (A24) address space. The size of
* the block will be equal to or greater than nBytes.  If the A24 memory
* partition has not already been created with sysA24MapRam() it will be
* allocated now if possible.
* 
* RETURNS: A pointer to the allocated block, or NULL if the buffer could
* not be allocated.
*
* SEE ALSO: sysA24MapRam(), sysA24Free()
*/

void *sysA24Malloc
    (
    unsigned nBytes	/* number of bytes to allocate */
    )
    {
    if (a24MemPartId == NULL)
	if (sysA24MapRam(nBytes + MEM_PART_OVERHEAD) != OK)
	    return NULL;

    return memPartAlloc(a24MemPartId, nBytes);
    }

/*******************************************************************************
*
* sysA24Free - free a block of memory from the A24 partition
*
* This routine returns to the A24 partition a block of memory that was
* previously allocated with sysA24Malloc().
*
* RETURNS: OK, or ERROR if the block is invalid.
*
* SEE ALSO: sysA24MapRam(), sysA24Malloc()
*/

STATUS sysA24Free
    (
    char *pBlock	/* pointer to block of memory to free */
    )
    {
    if (a24MemPartId == NULL)
	return ERROR;

    return memPartFree(a24MemPartId, pBlock);
    }

/*******************************************************************************
*
* sysA24MemShow - report status of the A24 memory partition
*
* This routine calls memPartShow for the A24 memory partition
*
* RETURNS: N/A
*
* SEE ALSO: sysA24MapRam(), sysA24Malloc(), sysA24Free()
*/

void sysA24MemShow(void)
    {
	if (a24MemPartId)
	    {
	    memPartShow(a24MemPartId, 0);
	    }
	else
	    puts("\nNo A24 memory currently reserved");
    }

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System