Motorola CPCI-6115 manual Interrupt Controller, PCI Bus Arbitration

Functional Description MV64360 System Controller

the second function, the controller is used by the system software to read the contents of the VPD EEPROM contained on the CPCI-6115 board, along with the SPD EEPROMs for the onboard memory banks, to further initialize the memory controller and other interfaces. See the programming model section of this document for more information including I2C bus device addressing.

The CPCI-6115 board has the following I2C serial devices connected to this I2C bus:

z8 KB EEPROM for user defined MV64360 initialization

z8 KB EEPROM for VPD

z8 KB EEPROM for user data

zTwo 256-byte EEPROMs for SPD

zDS1621 Temperature Sensor

The 8 KB devices are Atmel AT24C04N Serial EEPROMs.

4.3.4.12 Interrupt Controller

The CPCI-6115 uses the interrupt controller integrated into MV64360 to manage the MV64360 internal interrupts, as well as external interrupt requests. The interrupts are routed to the MV64360 MPP pins from onboard resources as shown in Figure 4-2 on page 75. The external interrupt sources include the following:

zOnboard PCI device interrupts

zPMC slot interrupts

zRTC interrupt

zWatchdog timer interrupts

zABORT switch interrupt

zExternal UART interrupts

zCompactPCI interrupts

zEthernet PHY interrupts

For added information on external interrupt assignments, refer to the MCPN905 CompactPCI Single Board Computer Programmer’s Reference Guide.

4.3.4.13 PCI Bus Arbitration

PCI arbitration is performed by the MV64360 chip. The MV64360 integrates two PCI arbiters, one for each PCI interface (PCI Bus 0.0/1.0). Each arbiter can handle up to six external agents plus one internal agent (PCI Bus 0.0/1.0 master). The internal PCI arbiter REQ#/GNT# signals are multiplexed on the MV64360 MPP pins. The internal PCI arbiter is disabled by default (the MPP pins function as general purpose inputs). Software will configure the MPP pins to function as request/grant pairs for the internal PCI arbiter. The arbitration pairs for the CPCI-6115 are assigned to the MPP pins as shown in the following table.

74 CPCI-6115 CompactPCI Single Board Computer Installation and Use (6806800A68D)