I'm tring to read PMA base haddress in order to throttle the cpu clock (Z510 / U15W) by bios.
Reference data sheet is :
Intel® System Controller Hub
External Design Specification (EDS)
To issue the read on Intel Sch Message Network I'm doing:
// Intel SCH Message Network (offset 0x70 port 4)
// opcode = 0xD0 (read)
// target port = 0x04
// Reg. Address = 0x70
// Byte Enable = 0x00
pciwrite32(0, 0, 0, 0xd4, 0x00000000); // Set MDR = 0
pciwrite32(0, 0, 0, 0xd0, 0xd0047000); // Issue Read command MCR
data32 = pciread32(0, 0, 0, 0xd4);
sprintf(buffer, "HOST BRIDGE PMBA = 0x%08X\n\r", data32);
The return code is always 0x4 (data32) what's wrong?
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J. Felix McNulty
Community Moderator (Intel contractor)