Abstract: There is disclosed in one example a multi-core computing system configured to provide a hot-swappable CPU0, including: a first CPU in a first CPU socket and a second CPU in a second CPU socket; a switch including a first media interface to the first CPU socket and a second media interface to the second CPU socket; and one or more mediums including non-transitory instructions to detect a hot swap event of the first CPU, designate the second CPU as CPU0, determine that a new CPU has replaced the first CPU, operate the switch to communicatively couple the new CPU to a backup initialization code store via the first media interface, initialize the new CPU, and designate the new CPU as CPUN, wherein N?0.

Abstract: There is disclosed in one example a multi-core computing system configured to provide a hot-swappable CPU0, including: a first CPU in a first CPU socket and a second CPU in a second CPU socket; a switch including a first media interface to the first CPU socket and a second media interface to the second CPU socket; and one or more mediums including non-transitory instructions to detect a hot swap event of the first CPU, designate the second CPU as CPU0, determine that a new CPU has replaced the first CPU, operate the switch to communicatively couple the new CPU to a backup initialization code store via the first media interface, initialize the new CPU, and designate the new CPU as CPUN, wherein N?0.

Abstract: Technologies for control and status register (CSR) access include a computing device that starts a firmware initialization phase. The firmware accesses a CSR at an abstract CSR address. The computing device determines whether an upper part of the CSR address matches a cached upper part of a previously accessed CSR address. If the upper parts do not match, the computing device converts the CSR address into a physical address and caches the upper part of the CSR address and the upper part of the physical address. If the upper parts match, the computing device combines a cached upper part of a previously accessed physical address with an offset of the CSR address. The upper part may include 20 bits and the lower part may include 12 bits. The physical address may be a PCIe address of the CSR added with an MMCFG base address. Other embodiments are described and claimed.

Abstract: Technologies for control and status register (CSR) access include a computing device that starts a firmware initialization phase. The firmware accesses a CSR at an abstract CSR address. The computing device determines whether an upper part of the CSR address matches a cached upper part of a previously accessed CSR address. If the upper parts do not match, the computing device converts the CSR address into a physical address and caches the upper part of the CSR address and the upper part of the physical address. If the upper parts match, the computing device combines a cached upper part of a previously accessed physical address with an offset of the CSR address. The upper part may include 20 bits and the lower part may include 12 bits. The physical address may be a PCIe address of the CSR added with an MMCFG base address. Other embodiments are described and claimed.