nnpi(7) —

NAME

nnp − Number Nine PEPPER PRO1024ISA driver

DESCRIPTION

The Number Nine PEPPER PRO1024ISA kernel driver facilitates accessing the Number Nine PEPPER PRO1024ISA board. It is a regular character-based driver that manages one PRO1024ISA board. It is used by programs that draw using the graphics modes of the PRO1024ISA.

CONFIGURATION

The sdevice(4) file /etc/conf/sdevice.d/nnpi describes the memory addresses of the PRO1024ISA board. The ninth and tenth fields in this file describe the starting and ending memory addresses. These fields are given in hexadecimal. The default sdevice file entry with an memory base address of C:C000 is:

nnpi Y 1 0 0 0 0 0 cc000 ccfff

As an example, if you want to change the default sdevice to use an addresses of D:C000, then the following sdevice file is used:

nnpi Y 1 0 0 0 0 0 dc000 dcfff

If you change the default sdevice entry, you will have to build a new kernel and boot it for these changes to become effective.

PROGRAMMING INTERFACE

The Number Nine PEPPER PRO1024ISA device is opened by a call to open. Currently, only minor device 0 is supported. If a non-zero minor device is specified, then an error will occur and errno will be set to ENOENT. A simple check is done to see if the PRO1024ISA board is in the system. If it is not, an error will result and errno will be set to ENXIO. A memory address clash may also cause this error. Only one user is allowed to open the PRO1024ISA board at a time, unless the subsequent user is the superuser. If a subsequent open is attempted by another user who is not the superuser, an error will result and errno will be set to EPERM.

Read and write interfaces are provided to access the memory of the Texas Instruments 34010 processor in the PRO1024ISA. Seek addresses are specified in bytes. Because addresses on a 34010 processor are given in bits, it is necessary to divide the bit address by 8 to get a byte address. The state of the 34010 is saved before each read and write, and restored when completed.

The following ioctl calls allow a user program to access the PRO1024ISA board directly:

NNPI_GET_INFO
This ioctl returns a structure containing the addresses of the board described in the section “Configuration” above. The structure returned is:

typedef struct nnpi_info {
char*nnpi_addr;/* physical address */
char*nnpi_endaddr; /* physical address */
} nnpi_info_t;

This structure is filled in with information in the ninth through tenth fields of the sdevice file. It is stored at the location specified by the argument that is passed.

NNPI_MAP_BOARD
This ioctl allows the process to have direct access to the PRO1024ISA memory. The argument passed is the address of the memory to map to the PRO1024ISA board. It must be page (4096 byte) aligned and span a length specified by the sdevice file (which is also a multiple of 4096 bytes). The memory that had existed at the argument passed will be irretrievably deleted, and the current contents of the PRO1024ISA memory will be placed at those locations. One way of allocating the virtual memory in the user’s address space that will be mapped to the PRO1024ISA memory is to call malloc requesting (length + 4096) bytes. Then, using the address that malloc returns, round it up to the next page (4K) boundary and use the result as the argument to this ioctl.

NNPI_UNMAP_BOARD
This ioctl call unmaps the direct access to the PRO1024ISA memory. The map must have been set up with NNPI_MAP_BOARD by the current process. The argument passed should be the same one given to NNPI_MAP_BOARD. The memory where the PRO1024ISA memory had been becomes zeros.

FILES

/dev/nnpi

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