Booting a computer system at start-up by transferring a first part of instructions using a second bus and transferring a second part of instructions using a first bus where the second bus is configured to transfer instructions at a faster rate than the first bus
View Patent ↗A computing device is provided that includes a computing unit, which has a working memory and a processing unit, and a boot memory having control instructions for operating the computing device. The control instructions are stored in boot memory and are to be transferred to the computing unit at start-up of the computing device. A boot control unit is connected to the computing unit by at least a first and a second interface and connected to the boot memory by a third interface. The boot control unit is configured to transfer a first part of the control instructions from the boot memory via the first interface to the computing unit and to transfer a second part of the control instructions from the boot memory via the second interface to the computing unit.
1. A computing device comprising:
a computing unit having a working memory and a processing unit;
a boot memory having control instructions to be transferred to the computing unit at start-up of the computing device, the control instructions configured to operate the computing device; and
a boot control unit connected to the computing unit by a first bus and a second bus and connected to the boot memory by a third bus, the boot control unit configured to transfer a first part of the control instructions configured to initialize the second bus from the boot memory via the first bus to the computing unit and to transfer a second part of the control instructions from the boot memory via the second bus to the computing unit, where the second bus is configured to transfer data at a faster rate than the first bus.
2. The computing device of claim 1 where the second part of the control instructions is larger than the first part.
3. The computing device of claim 1 where the boot control unit includes a direct memory access controller for transferring the second part of the control instructions via the second bus into the working memory of the computing unit.
4. The computing device of claim 1 where the boot control unit includes a field-programmable gate array or an application specific integrated circuit.
5. The computing device of claim 1 where the first bus is a low pin count bus and the second bus is a peripheral component interconnect express bus.
6. The computing device of claim 1 where the computing unit includes a system controller hub having the first and the second buses, and connected to the working memory.
7. The computing device of claim 6 where the boot memory includes a flash memory, the computing unit includes an Intel® Menlow platform with the system controller hub and the processing unit is an x86-compatible microprocessor.
8. The computing device of claim 1 where the first part of the control instructions includes control instructions for initializing the second bus, the boot control unit being configured to transfer the second part of the control instructions after initialization of the second bus.
9. A method of operating a computing device having a computing unit having a working memory and a processing unit, a boot memory having control instructions for operating the computing device to be transferred to the computing unit at start-up of the computing device, and a boot control unit connected to the computing unit by at least a first bus and a second bus and to the boot memory by a third interface, the method comprising:
retrieving the control instructions from the boot memory by the boot control unit;
transferring a first part of the control instructions configured to initialize the second bus via the first bus to the computing unit, where the second bus is configured to transfer data at a faster rate than the first bus; and
transferring a second part of the control instructions via the second bus to the computing unit.
10. The method of claim 9 where the control instructions are stored in a compressed format in the boot memory, the method further comprising:
decompressing the control instructions after the compressed control instructions are received at the computing unit.
11. The method of claim 9 where the computing unit further includes a system controller hub having the first and the second bus, and connected to the working memory.
12. A computing device comprising:
a computing unit having a working memory, a processing unit and a system controller hub connected to the memory and the processing unit;
a boot memory having control instructions for operating the computing device to be transferred to the computing unit at start-up of the computing device; and
a boot control unit connected to the system controller hub of the computing unit by at least a first and a second bus and connected to the boot memory by a third bus, the boot control unit configured to transfer a first part of the control instructions configured to initialize the second bus from the boot memory via the first bus to the computing unit and to transfer a second part of the control instructions from the boot memory via the second bus to the computing unit, the second bus being configured to transfer data at a faster rate than the first bus.