C Address Space Conflicts with Other Hardware

This appendix describes various address space conflicts which may arise when the SNC is added to a server that contains other hardware. These conflicts may arise in the interrupt vector address space, the VME address space or the DVMA space.

C.1 Changing Interrupt Vectors Because of Conflicts

Sun Microsystems reserves a set of interrupt vectors in the kernel for other devices. The range of these vectors is from 0xc8 to 0xff. By default the SNC uses the interrupt vectors shown in the table below:

Table C-1 Interrupt Vectors for the Sun Network CoProcessor

It is possible that other hardware previously installed in a server conflicts with the interrupt vectors used by an SNC. If there is a conflict the system will show evidence of spurious interrupts and even system panics. To correct the situation you should change the interrupt vectors used by the SNC or the device with which they conflict.

To change the interrupt vectors used by the SNC perform the following steps:

1. Change directory to/sys/sun{ 4 | 4m }/conf.

2. Edit the kernel configuration file. The name of the kernel can be found in the message of the day file /etc/motd.

Note - All of the interrupt vectors for hardware on a given system are defined in the kernel configuration file. You can examine which vectors are being used and make your modifications accordingly.

3. Find all of the device ne? lines that are similar to those shown below:

4. Change the interrupt vector numbers in the lines that begin with vector to a value that will not conflict with other installed hardware.

5. Write and terminate the edit of the file.

6. Build the kernel configuration files for the new kernel:

7. Change directories to ../NAME_SNC

8. Make the kernel.

9. Remove the old kernel.

10. Move the kernel you have just created to the root directory. The kernel can be over a megabyte in length. Be sure you have enough space for it.

11. If it does not already exist make a symbolic link to the kernel you just moved.

12. Reboot the system to install the new SNC kernel.

C.2 Changing VME Address Space Because of Conflicts

The SNC uses a set of 16-bit VME addresses and a set of 32/24-bit VME addresses. These addresses may conflict with the VME address used by other boards already configured in your system. If there is a conflict, these addresses must be changed.

SNC uses the 32-bit VME address space on Sun 600MP servers, and uses 24-bit VME address space on all other Sun systems. It is possible that the SNC 32/24- bit VME addresses may conflict with another vendor's board that uses either 32-bit or 24-bit VME addresses.

The default address space used by the SNC for 16 and 32/24-bit addresses is shown below:

Table C-2 Default Address Space For The SNC

Note - The following list of alternate addresses may be used. Any 16-bit VME address may be used with any 24-bit address, assuming the configuration file and switches on the board are set correctly.

Table C-3 Alternate Address Space For The SNC

Look at the address space used by other hardware to see that there is a VME address space conflict. This should be defined in the hardware documentation. It may help to examine the controller and device lines in the configuration file. Cchange the switch settings on the boards to change the SNC VME address space. If you change the switch settings for the VME address space, you must change the kernel configuration files and rebuild the kernel.

To change the VME address space used by the SNC:

1. Prepare the system for hardware adjustments.

a. Shutdown the system

b. Power down the system and unplug it.

c. Remove any cover panels that are in the way.

2. Perform the following steps.

a. Remove the SNC from the system.

Note - The following examples give several alternative VME addresses and the switch settings that correspond to them.

b. If the 16-bit VME address space for an SNC board conflicts with existing devices in the system change the address jumpers on the board. Make a note of the jumper setting and the 16-bit VME address selected. See Figure C-2, note that jumpers marked in gray should not be moved.

Figure C-1 SNC Jumper Settings for 16-bit VME Address Spaces

c. If the 16-bit VME address space for an switched SNC board conflicts with existing devices in the system change Switch 1 on the board. Make a note of the switch setting and the 16-bit VME address selected. See Figure C-2.

Figure C-2 Switched SNC Switch Settings for 16-bit VME Address Spaces

Figure C-3 shows 32/24-bit VME addresses as set by the jumpers on an SNC. In the figure, jumpers JP1 through JP13 correspond to the high-order 13 bits of 32-bit VME addresses, and the JP9 through JP13 jumpers correspond to the high-order five bits of 24-bit VME addresses.

Figure C-3 32-bit VME Address Jumper Assignments

The ?????? notation in Figure C-3 corresponds to 32/24-bit VME addresses as indicated by the setting of switch 2 on a switched SNC.

Figure C-4 sw3: 32-bit VME Address Switch Setting Example

Note - All eight switches on switch 3 are significant.They change the high- order eight bits of the 32-bit addresses that cause the SNC to respond.

Note - Changing the value of switch 3 will not remove any 24-bit VME address conflict that might exist. You should change the value of switch 3 only if you encounter 32-bit VME address conflicts with the 32/24-bit VME addresses used by the SNC. To change 24-bit VME addresses on the SNC, you must change switch 2 only.

d. If the 32/24-bit VME address space conflicts with existing devices in the system change Switch 2 on the board. Make a note of the switch setting and the 24-bit VME address space selected. See Figure C-5, note that the gray jumpers shown should not be changed when setting the VME addresses.

Figure C-5 SNC Jumper Settings for 32/24-bit VME Address Space

e. If the 32/24-bit VME address space of a switched SNC board conflicts with existing devices in the system change Switch 2 on the board. Make a note of the switch setting and the 24-bit VME address space. selected. See Figure C-6.

Figure C-6 SNC Switch Setting for 24-bit VME Address Space

3. Repeat the steps above for each SNC that conflicts with existing boards. Replace the boards.

4. Power up and reboot the system.

5. Make appropriate changes to the kernel configuration file.

a. Change directories to /sys/sun{4 | 4m}/conf.

b. Edit the kernel configuration file. The name of the kernel can be found in the message of the day file /etc/motd.

c. Find all of the device ne? lines that are similar to those shown below:

d. If you changed the 16-bit VME address space on the SNC boards, change the 0x6000, 0x6800, 0x5000, 0x5800, 0x2000, 0x2800, 0x3000, or 0x3800 VME addresses to their new values.

e. If you changed the 32/24-bit VME address space on the boards, change the 0x00a00000, 0x00a80000, 0x00b00000, 0x00b80000, 0x00c00000, 0x00c80000, 0x00d00000, or 0x00d80000 VME addresses to their new values.

f. Write and terminate the edit of the file.

6. Build and install an SNC kernel.

a. Change directory to /sys/sun{ 4 | 4m }/conf .

b. Build the kernel configuration files for the new kernel:

c. Change directories to ../filename.

d. Make the kernel.

e. Remove the old kernel.

f. Move the kernel you have just created to the root directory. The kernel can be over a megabyte in length. Be sure you have enough space for it.

g. If it does not already exist make a symbolic link to the kernel you just moved.

7. Reboot your system with the new kernel.

C.3 Correcting DVMA Address Space Conflicts

The SNC uses Direct Virtual Memory Access (DVMA) to transfer data between itself and the host server. The size of the DVMA memory space used by SNC hardware is not a configurable option. If the sum of all DVMA space used by the peripherals installed in a server is greater than the amount available, some of the peripherals in the server will not run correctly.

The issues associated with DVMA address space conflicts vary, depending on whether you have installed the SNC in a SPARCserver 400 or SPARCserver 600.

C.3.1 DVMA Address Space Conflicts on SPARCserver 400

Solaris 1.x reserves about one megabyte of DVMA space for peripherals on SPARCserver 400's. The following table shows the amount of DVMA address space used by the SNC hardware.

Table C-4 DVMA Address Space Used by The SNC on SPARCserver 400

If the SPARCserver does not have the needed DVMA space, you must modify the configuration of your server to allow more DVMA space for the installed SNC(s).

C.3.2 DVMA Address Space Conflicts on SPARCserver 600

SunOS 4.1.2 has 6 Megabytes of DVMA (Direct Virtual Memory Access) space available for use by VME32 peripheral devices on SPARCserver 600MP systems. The use of DVMA space by various devices is not configurable. The SNC driver maps in 416 kilobytes of DVMA space for each SNC board at boot time. If the sum of all DVMA space requested by VME32 devices ever exceeds 6 Megabytes, some of those devices in your system will not run correctly. In this case the only solution is to remove some VME32 device(s) from the hardware configuration.