Method for realizing peripheral access control based on MMU (memory management unit) in ARM virtual machine

Abstract

The invention provides a method for realizing peripheral access control based on MMU (memory management unit) in an ARM virtual machine. The method comprises the following steps of: firstly, for a peripheral device required to be monitored by the virtual machine, changing a segmental page table item mapping corresponding to the physical register address of the peripheral device in each upper operating system; changing the position Domain in a corresponding page table item to a wrong value and simultaneously establishing a correct address mapping of the peripheral device in the address space of a bottom virtual machine wherein the bottom virtual machine takes over the data exception processing of hardware to capture possible address access mistakes of the upper operating systems; if Domain Fault occurs during address translation of the MMU when the upper operating systems access the address of the peripheral device, entering data exception processing mode of a processor; judging whether the mode is of the Domain Fault type or not by reading a hardware register when the action is captured by the virtual machine; if not, returning to the address space of the operating systems; and if so, processing the current access data of the operating systems by the bottom virtual machine, and allowing the virtual machines to access the corresponding peripheral register according to the processed data. The method solves the problem that the conflict of access to the same one peripheral device occurs when multiple operating systems run at the same time.

Description

technical field [0001] The invention belongs to the field of embedded virtualization technology, and relates to an implementation method of MMU-based peripheral access control in an ARM virtual machine, which is suitable for managing and controlling access to peripherals by an operating system running on the upper layer of the underlying virtual machine, and can satisfy Multiple operating systems have different access requirements to peripherals under the same hardware platform. Background technique [0002] In recent years, the popularization of mobile phones and tablet computers has set off an upsurge in the development of embedded operating systems and embedded applications. Many excellent embedded operating systems and corresponding applications have emerged on the market, and ARM processors because of their high performance And low power consumption, has become the most popular embedded application processor. In order to avoid the transplantation of applications develo...

AI Technical Summary

Problems solved by technology

[0008] However, running multiple operating systems on the same hardware platform at the same time may cause access conflicts between multiple operating systems on the same peripheral. normal operation of

The existing public solutions to this problem are generally difficult to implement, and the overall performance loss caused by the implementation is also relatively large

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