Software Environments - Heterogeneous Multicore Processor Technologies for Embedded Systems - page 151

Chapter 5
Software Environments

5.1 Linux ® on Multicore Processor

Linux 1 is one of the operating systems capable of symmetric multiprocessing (SMP).
In this subsection, we describe the work of porting SMP Linux to the RP-1, RP-2,
and RP-X multicore chips which are explained in Chap. 4, and extending functions
of Linux to use the new processor's features. Each chip has the following special
points:

￿ RP-1: The first SMP-ready multicore processor of SuperH™

2 (SH) architecture
RP-2: The second SMP-ready multicore processor which has enhanced power- ￿

saving features
RP-X: The SMP-ready multicore processor with 40-bit physical addressing ￿

We have extended Linux in the following steps:

￿ Porting SMP Linux to RP-1

￿ Extending a power-saving feature of Linux to RP-2

￿ Developing a physical address extension feature of Linux to RP-X

The details of the work are described in the following sub-subsections:

5.1.1 Porting SMP Linux

5.1.1.1 Introduction

Linux source code consists of architecture-dependent and architecture-independent
parts. The architecture-independent part is common among all processor architectures.

1 Linux ® is the registered trademark of Linus Torvalds in the USA and other countries.
2 SuperH™ is a trademark of Renesas Electronics.