On 02/29/16 14:19, Gerd Hoffmann wrote: > Hi, > >> I didn't mean "fw_cfg-based configuration" as another, "new" config >> knob. I just recall some discussions that "etc/reserved-memory-end" is >> related to the 64-bit MMIO aperture, somehow. (I don't yet know how >> exactly -- I intended to ask about it anyway, later). > > Ah, that one you mean. It's simple: Firmware should not place anything > between 4G and the address given in etc/reserved-memory-end. It's > reserved address space for memory hotplug (and possibly other stuff).
Okay, OVMF does not conform to this at the moment. It fetches the amount of RAM above the 4GB mark from the CMOS, and makes it all available to the DXE and later phases (and the OS as well). Assuming the "etc/reserved-memory-end" fw_cfg file is found, how does that affect the CMOS value? Let's say the CMOS value is 2GB, and the reserved-memory-end file is 1GB. Which of the following true is correct: - 1GB gap between 4GB and 5GB, 1GB memory between 5GB and 6GB - 1GB gap between 4GB and 5GB, 2GB memory between 5GB and 7GB Also (assuming either answer): in that 4GB->5GB gap, where exactly should I place the 64-bit PCI MMIO aperture, so that it doesn't interfere with memory hotplug during OS runtime? Thanks Laszlo _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
