Broadcom BCM1250 User Manual page 225

User Manual
10/21/02
Compatibility space routing is summarized in the pseudo-code below:
if (00_4000_0000 <= zbaddr <= 00_7FFF_FFFF)
{
pcildtaddr = zbaddr & DFFF_FFFF
endian = zbaddr[29] ? match bit lanes : match byte lanes
if (pcildtaddr < 00_4100_0000) /* Note after a[29] removal */
{
}
else if (HT mem base <= pcildtaddr <= HT mem limit)
else
}
Document 1250_1125-UM100CB-R
if (pcildtaddr[23:17] == 7'b0000101) /* 0A_xxxx/0B_xxxx */
{
if (Bridge Control VgaEn)
send (pcildtaddr & 00FF_FFFF) to HT with COMPAT bit clear
else
send (pciaddr & 00FF_FFFF) to PCI
}
else
{
if (Southbridge is on LDT)
send (pcildtaddr & 00FF_FFFF) to HT with COMPAT bit set
else
send (pciaddr & 00FF_FFFF) to PCI
}
send to HT
send to PCI
B r oadco m C orp or ati on
BCM1250/BCM1125/BCM1125H
Section 8: PCI Bus and HyperTransport Fabric Page 197