SMART 6873M Artwork, Инструкция по установке и эксплуатации

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Functional Description
ATCA-F125 (6873M Artwork) Installation and Use (6806800J94N) 75
4.5.1 Serial Configuration PROM
The FPGA is configured at power up by loading the contents of an Atmel AT45DB041 SPI
PROM device. This configuration uses standard SPI Flashes for the FPGA configuration.
For fault recovery during the remote upgrade of the FPGA PROM, the ATCF125 board will
provide a backup SPI device. Both PROMs will be programmed with identical images
during the production process. The IPMI infrastructure can be used to select the secondary
boot device. The primary PROM device is selected by default.
The SPI device chain will also include the SPI device for the BCM8747 microcode so that
it can be upgraded by the service processor.
There are four different modes of operation for the FPGA and the SPI flash devices:
 FPGA Configuration - The FPGA automatically controls the CSO_B, CCLK and
MOSI pins and reads the configuration data over DIN. Whether the configuration
data is supplied by SPI Flash 1 or 2 is determined by the routing of the CSO_B
signal which is controlled by the IPMC. AUX_SS is deasserted by virtue of the fact
the FPGA is not configured.
 Configuration Flash programming - A SPI controller in the FPGA (driven by the
service processor over the local bus) controls CSO_B, CCLK and MOSI, and
monitors DIN. The IPMC has to select the chip select routing for the primary SPI
device. The secondary SPI device, which is for fail-safe backup purposes only, is
write protected and cannot be programmed in the field through the FPGA SPI
interface. AUX_SS is deasserted by the SPI controller.
 BCM8747 microcode Flash programming - The same SPI controller in the FPGA
is used as with configuration Flash programming, but now AUX_SS is driven
instead of CSO_B (which is deasserted), allowing SPI Flash 3 to be programmed.
 BCM8747 microcode loading - The SPI port from the BCM8747 is routed to
AUX_CS, CCLK, MOSI and DIN pins in the FPGA to allow the microcode to be
read from SPI Flash 3.