Broadcom BCM5722 - Figure 82: PCI-Specified Reset Interval

Programmer’s Guide BCM5722
10/15/07
Broadcom Corporation
Document 5722-PG101-R Expansion ROM Access After PCI Reset Page 530
Appendix C: Timing Considerations
EXPANSION ROM ACCESS AFTER PCI RESET
After the device is reset, ROM code in the device takes 20 ms to 50 ms (depending on the size of the boot firmware) to load
the initial firmware code stored in the NVRAM. This initial firmware code then enables the PCI Expansion ROM retry until
PXE code is completely loaded from NVRAM to Internal Memory. PXE loading process can take up to 3 or 4 seconds.
Expansion ROM auto-retry is removed when PXE code is completely loaded, which only occurs if PXE is administratively
enabled. If host software accesses the expansion ROM before the loading process has completed, the device will not target
terminate with a retry.
Figure 82: PCI-Specified Reset Interval
PCI specified reset interval
RST
2exp25 clocks
20 ms–50 ms
Access to expansion ROM after
20 ms–50 ms auto-retries
P
CI_CLK