1.2. Hardware Dependency

Linux tries to maintain a neat distinction between hardware-dependent and hardware-independent source code. To that end, both the arch and the include directories include 23 subdirectories that correspond to the different types of hardware platforms supported. The standard names of the platforms are:

alpha

Hewlett-Packard's Alpha workstations (originally Digital, then Compaq; no longer manufactured)

arm, arm26

ARM processor-based computers such as PDAs and embedded devices

cris

"Code Reduced Instruction Set" CPUs used by Axis in its thin-servers, such as web cameras or development boards

frv

Embedded systems based on microprocessors of the Fujitsu's FR-V family

h8300

Hitachi h8/300 and h8S RISC 8/16-bit microprocessors

i386

IBM-compatible personal computers based on 80x86 microprocessors

ia64

Workstations based on the Intel 64-bit Itanium microprocessor

m32r

Computers based on the Renesas M32R family of microprocessors

m68k, m68knommu

Personal computers based on Motorola MC680x0 microprocessors

mips

Workstations based on MIPS microprocessors, such as those marketed by Silicon Graphics

parisc

Workstations based on Hewlett Packard HP 9000 PA-RISC microprocessors

ppc, ppc64

Workstations based on the 32-bit and 64-bit Motorola-IBM PowerPC microprocessors

s390

IBM ESA/390 and zSeries mainframes

sh, sh64

Embedded systems based on SuperH microprocessors developed by Hitachi and STMicroelectronics

sparc, sparc64

Workstations based on Sun Microsystems SPARC and 64-bit Ultra SPARC microprocessors

um

User Mode Linux, a virtual platform that allows developers to run a kernel in User Mode

v850

NEC V850 microcontrollers that incorporate a 32-bit RISC core based on the Harvard architecture

x86_64

Workstations based on the AMD's 64-bit microprocessorssuch Athlon and Opteron and Intel's ia32e/EM64T 64-bit microprocessors