NAME

VPA − Sun vector processor accelerator

CONFIG — SUN-3 or SUN-4

vpa0 at vme32d32 ?  csr 0x200000 flags 0x20000000 priority 2

vpa1 at vme32d32 ?  csr 0x202000 flags 0x22000000 priority 2

vpa2 at vme32d32 ?  csr 0x204000 flags 0x24000000 priority 2

vpa3 at vme32d32 ?  csr 0x206000 flags 0x26000000 priority 2

DESCRIPTION

The VPA is a vector processor accelerator available for Sun-3 and Sun-4 systems. 

The vpa device driver emulates a character special device, but includes capabilities for mapping VPA registers and memory into an application’s virtual address space, as well as a simple capability to signal the occurence of interrupts to the process running the application. 

The driver supports the following operations:

open(2)
The driver can support multiple open devices, but only a single device /dev/vpa0 is guaranteed to work properly with other Sun hardware and software. 

close(2)
This is called automatically when the process terminates.  Upon closing, the driver resets and disables the VPA’s memory.

mmap(2)
This is used to map VPA memory into the application’s virtual address space.  When the system is booted, the VPA data memory is automatically sized.  The offset parameter to mmap(2) is used to select whether to map the registers or data memory with this call. An offset of 0 maps the register page.  An offset of NBPG (number of bytes in a page) yields the first byte of data (program) memory.  Before returning, the driver enables VPA memory.  If an application needs to access program memory instead, that application must issue the appropriate command to the status register (a call to mmapp using an offset of 0). 

read(2) and write(2) are not supported on this device.

IOCTLS

VPAGETMEMSZ
Return the size of the VPA data memory. 

SIGNALS

SIGURG is sent to the process when an interrupt occurs.  The process is expected to read the VPA status register to determine the cause of the interrupt, and do its own processing of that interrupt.  The driver doesn’t modify the state of the VPA. 

FILES

/dev/vpa0 sys/sundev/vpa_reg.h

SEE ALSO

mmap(2)
 

Sun Release 3.5  —  Last change: 4 July 1987