Communication of device presence between boot routine and operating system

Various embodiments are directed to creating multiple device blocks associated with hardware devices, arranging the device blocks in an order indicative of positions of the hardware devices in a hierarchy of buses and bridges, and enabling access to the multiple device blocks from an operating system. An apparatus comprises a processor circuit and storage storing instructions operative on the processor circuit to create a device table comprising multiple device blocks, each device block corresponding to one of multiple hardware devices accessible to the processor circuit, the device blocks arranged in an order indicative of relative positions of the hardware devices in a hierarchy of buses and at least one bridge device; enable access to the device table by an operating system; and execute a second sequence of instructions of the operating system operative on the processor circuit to access the device table. Other embodiments are described and claimed herein.