Alpha AXP 體系結構是一個爲了速度而設計的 64 位的加載 / 存儲（ load/store
） RISC 體系結構。所有的寄存器都是 64 位長的： 32 個整數寄存器和 32 個
浮點寄存器。第 31 個整數寄存器和第 31 個浮點寄存器用於 null 操作：讀取它
們得到 0 ，寫向它們沒有任何結果。所有的指令和內存操作（不管是讀或寫）都
是 32 位。只要具體的實現遵循這種體系結構，允許不同的實現方式。
沒有直接在內存中操作數值的指令：所有的數據操作都是在寄存器之間進行。所以
，如果你希望增加內存中一個計數器，你必須首先把它讀到一個積存其中，修改之
後再寫回去。只有通過一個指令寫向一個寄存器或內存位置，而另一個讀取這個寄
存器或內存位置，指令之間才能過相互作用。 Alpha AXP 的一個有趣的特點是它
有可以產生標誌位的指令，比如測試兩個整數是否相等，這個結構不是存放到處理
器的一個狀態寄存器，而是存放到第三個寄存器。初看上去比較奇怪，但是不依賴
於狀態寄存器意味着可以更容易地讓這個 CPU 每一個循環執行多個指令。執行過
程中使用無關的寄存器的指令不需要互相等待，如果只有一個狀態寄存器則必須等
待。沒有對於內存的直接操作以及數目衆多的寄存器對於同時多條指令也有幫助。
Alpha AXP 體系結構使用一系列子例程，叫做體系結構的授權庫代碼（
privileged architecture library code PALcode ）。 PALcode 和操作系統、
Alpha AXP 體系的 CPU 具體實現和系統硬件相關。這些子例程向操作系統提供上
下文切換、中斷、異常和內存管理的基本支持。這些子例程可以被硬件調用或通過
CALL_PAL 指令調用。 PALcode 用標準的 Alpha AXP 彙編程序編寫，帶有一些特
殊擴展的實現，用於提供直接訪問低級硬件的功能，例如內部處理器的寄存器。
PALcode 在 PAL 模式運行，這是一個特權的模式，會停止一些系統事件的發上，
並允許 PALcode 完全控制系統的物理硬件。
Appendix C （附錄 C ）
Useful Web and FTP Sites （有用的 web 和 ftp 站點）
http://www.azstarnet.com/~axplinux ;This is David Mosberger-Tang'sAlpha
AXP Linux web site and it is the place to go for all of the Alpha AXP
HOW-
TOs. It also has a large number of pointers to Linux and Alpha AXP
specific
information such as CPU data sheets.
http://www.redhat.com/ ;Red Hat's web site. This has a lot of usefulpointers.
ftp://sunsite.unc.edu ;This is the major site for a lot of free software.The Linux
specfic software is held in pub/Linux.
http://www.intel.com ;Intel's web site and a good place to look for Intelchip
information.
http://www.ssc.com/lj/index.html ;The Linux Journal is a very goodLinux
magazine and well worth the yearly subscription for its excellent
articles.
http://www.blackdown.org/java-linux.html ;This is the primary site forinfor-
mation on Java on Linux.
ftp://tsx-11.mit.edu/ ;~ftp/pub/linux MIT's Linux ftp site.ftp://ftp.cs.helsinki.fi/pub/Software/Linux/Kernel ;Linus's kernelsources.
http://www.linux.org.uk ;The UK Linux User Group.http://sunsite.unc.edu/mdw/linux.html ;Home page for the Linux Documen-tation Project,
http://www.digital.com ;Digital Equipment Corporation's main web page.http://altavista.digital.com ;DIGITAL's Altavista search engine. A verygood
place to search for information within the web and news groups.
http://www.linuxhq.com ;The Linux HQ web site holds up to date officaland
unoffical patches as well as advice and web pointers that help you get
the best
set of kernel sources possible for your system.
http://www.amd.com ;The AMD web site.http://www.cyrix.com ;Cyrix's web site.Appendix D( 附錄 D)
The GNU General Public
License
Printed below is the GNU General Public License (the GPL or copyleft),
under
which Linux is licensed. It is reproduced here to clear up some of the
confusion
about Linux's copyright status|Linux is not shareware, and it is not
in the public
domain. The bulk of the Linux kernel is copyright c 1993 by Linus
Torvalds, and
other software and parts of the kernel are copyrighted by their authors.
Thus, Linux
is copyrighted, however, you may redistribute it under the terms of
the GPL printed
below.
GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundation, Inc. 675 Mass Ave,
Cambridge,
MA 02139, USA Everyone is permitted to copy and distribute verbatim
copies of
this license document． but changing it is not allowed.
D.1 Preamble
The licenses for most software are designed to take away your freedom to
share and
change it. By contrast, the GNU General Public License is intended to
guarantee
your freedom to share and change free software{to make sure the software
is free
for all its users. This General Public License applies to most of the
Free Software
Foundation's software and to any other program whose authors commit to
using
it. (Some other Free Software Foundation software is covered by the
GNU Library
General Public License instead.) You can apply it to your programs,
too.
When we speak of free software, we are referring to freedom, not price.
Our General
Public Licenses are designed to make sure that you have the freedom to
distribute
copies of free software (and charge for this service if you wish),
that you receive
source code or can get it if you want it, that you can change the
software or use
pieces of it in new free programs; and that you know you can do these
things.
To protect your rights, we need to make restrictions that forbid
anyone to deny
you these rights or to ask you to surrender the rights. These
restrictions translate
to certain responsibilities for you if you distribute copies of the
software, or if you
modify it.
For example, if you distribute copies of such a program, whether
gratis or for a fee,
you must give the recipients all the rights that you have. You must make
sure that
they, too, receive or can get the source code. And you must show them
these terms
so they know their rights.
We protect your rights with two steps: (1) copyright the software, and
(2) offer you
this license which gives you legal permission to copy, distribute and/or
modify the
software.
Also, for each author's protection and ours, we want to make certain
that everyone
understands that there is no warranty for this free software. If the
software is modified
by someone else and passed on, we want its recipients to know that
what they have
is not the original, so that any problems introduced by others will
not re ect on the
original authors' reputations.
Finally, any free program is threatened constantly by software patents.
We wish to
avoid the danger that redistributors of a free program will individually
obtain patent
licenses, in e
ect making the program proprietary. To prevent this, we have made it
clear that any patent must be licensed for everyone's free use or not
licensed at all.
The precise terms and conditions for copying, distribution and
modification follow.
D.2 Terms and Conditions for Copying, Distribu-
tion, and Modification 0. This License applies to any program or other
work which contains a notice
placed by the copyright holder saying it may be distributed under the
terms of
this General Public License. The /Program", below, refers to any such
program
or work, and a /work based on the Program" means either the Program or
any derivative work under copyright law: that is to say, a work
containing
the Program or a portion of it, either verbatim or with modifications
and/or
translated into another language. (Hereinafter, translation is
included without
limitation in the term /modification".) Each licensee is addressed as
/you".
Activities other than copying, distribution and modification are not
covered
by this License; they are outside its scope. The act of running the
Program is
not restricted, and the output from the Program is covered only if its
contents
constitute a work based on the Program (independent ofhaving been made
by
running the Program). Whether that is true depends on what the Program
does.
1. You may copy and distribute verbatim copies of the Program's source
code
as you receive it, in any medium, provided that you conspicuously and
appro-
priately publish on each copy an appropriate copyright notice and
disclaimer
of warranty; keep intact all the notices that refer to this License
and to the
absence of any warranty; and give any other recipients of the Program
a copy
of this License along with the Program.
You may charge a fee for the physical act of transferring a copy, and
you may
at your option offer warranty protection in exchange for a fee.
2. You may modify your copy or copies of the Program or any portion of
it,
thus forming a work based on the Program, and copy and distribute such
modifications or work under the terms of Section 1 above, provided
that you
also meet all of these conditions:
a. You must cause the modified files to carry prominent notices
stating that
you changed the files and the date of any change.
b. You must cause any work that you distribute or publish, that in whole
or
in part contains or is derived from the Program or any part thereof,
to
be licensed as a whole at no charge to all third parties under the terms
of
this License.
c. If the modified program normally reads commands interactively when
run,
you must cause it, when started running for such interactive use in
the
most ordinary way, to print or display an announcement including an
appropriate copyright notice and a notice that there is no warranty
(or
else, saying that you provide a warranty) and that users may
redistribute
the program under these conditions, and telling the user how to view a
copy of this License. (Exception: if the Program itself is interactive
but
does not normally print such an announcement, your work based on the
Program is not required to print an announcement.)
These requirements apply to the modified work as a whole. If
identifiable
sections of that work are not derived from the Program, and can be
reasonably
considered independent and separate works in themselves, then this
License,
and its terms, do not apply to those sections when you distribute them
as
separate works. But when you distribute the same sections as part of a
whole
which is a work based on the Program, the distribution of the whole must
be
on the terms of this License, whose permissions for other licensees
extend to
the entire whole, and thus to each and every part regardless of who
wrote it.
Thus, it is not the intent of this section to claim rights or contest
your rights
to work written entirely by you; rather, the intent is to exercise the
right to
control the distribution of derivative or collective works based on
the Program.
In addition, mere aggregation of another work not based on the Program
with
the Program (or with a work based on the Program) on a volume of a
storage
or distribution medium does not bring the other work under the scope
of this
License.
3. You may copy and distribute the Program (or a work based on it, under
Section
2) in object code or executable form under the terms of Sections 1 and 2
above
provided that you also do one of the following:
a. Accompany it with the complete corresponding machine-readable
source
code, which must be distributed under the terms of Sections 1 and 2
above
on a medium customarily used for software interchange; or,
b. Accompany it with a written offer, valid for at least three years, to
give any
third party, for a charge no more than your cost of physically
performing
source distribution, a complete machine-readable copy of the
correspond-
ing source code, to be distributed under the terms of Sections 1 and 2
above on a medium customarily used for software interchange; or,
c. Accompany it with the information you received as to the offer to
dis-
tribute corresponding source code. (This alternative isallowed only
for
noncommercial distribution and only if you received the program in
object
code or executable form with such an offer, in accord with Subsection
b above.)
The source code for a work means the preferred form of the work for
making
modifications to it. For an executable work, complete source code
means all
the source code for all modules it contains, plus any associated
interface defi-
nition files, plus the scripts used to control compilation and
installation of the
executable. However, as a special exception, the source code distributed
need
not include anything that is normally distributed (in either source or
binary
form) with the major components (compiler, kernel, and so on) of the
operating
system on which the executable runs, unless that component itself
accompanies
the executable.
If distribution of executable or object code is made by offering
access to copy
from a designated place, then offering equivalent access to copy the
source code
from the same place counts as distribution of the source code, even
though third
parties are not compelled to copy the source along with the object
code.
4. You may not copy, modify, sublicense, or distribute the Program
except as
expressly provided under this License. Any attempt otherwise to copy,
modify,
sublicense or distribute the Program is void, and will automatically
terminate
your rights under this License. However, parties who have received
copies, or
rights, from you under this License will not have their licenses
terminated so
long as such parties remain in full compliance.
5. You are not required to accept this License, since you have not
signed it. How-
ever, nothing else grants you permission to modify or distribute the
Program
or its derivative works. These actions are prohibited by law ifyou do
not ac-
cept this License. Therefore, by modifying or distributing the Program
(or any
work based on the Program), you indicate your acceptance of this License
to
do so, and all its terms and conditions for copying, distributing or
modifying
the Program or works based on it.
6. Each time you redistribute the Program (or any work based on the
Program),
the recipient automatically receives a license from the original
licensor to copy,
distribute or modify the Program subject to these terms and conditions.
You
may not impose any further restrictions on the recipients' exercise of
the rights
granted herein. You are not responsible for enforcing compliance by
third
parties to this License.
7. If, as a consequence of a court judgment or allegation of patent
infringement
or for any other reason (not limited to patent issues), conditions are
imposed
on you (whether by court order, agreement or otherwise) that
contradict the
conditions of this License, they do not excuse you from the conditions
of this
License. If you cannot distribute so as to satisfy simultaneously your
obligations
under this License and any other pertinent obligations, then as a
consequence
you may not distribute the Program at all. For example, if a patent
license
would not permit royalty-free redistribution of the Program by all those
who
receive copies directly or indirectly through you, then the only way you
could
satisfy both it and this License would be to refrain entirely from
distribution
of the Program.
If any portion of this section is held invalid or unenforceable under
any par-
ticular circumstance, the balance of the section is intended to apply
and the
section as a whole is intended to apply in other circumstances.
It is not the purpose of this section to induce you to infringe any
patents or
other property right claims or to contest validity ofany such claims;
this section
has the sole purpose of protecting the integrity of the free software
distribution
system, which isimplemented by public license practices. Many people
have
made generous contributions to the wide range of software distributed
through
that system in reliance on consistent application of that system; it
is up to the
author/donor to decide if he or she is willing to distribute software
through
any other system and a licensee cannot impose that choice.
This section is intended to make thoroughly clear what is believed to be
a
consequence of the rest of this License.
8. If the distribution and/or use of the Program is restricted in
certain countries
either by patents or by copyrighted interfaces, the original copyright
holder
who places the Program under this License may add an explicit
geographical
distribution limitation excluding those countries, so that
distribution is permit-
ted only in or among countries not thus excluded. In such case, this
License
incorporates the limitation as if written in the body of this License.
9. The Free Software Foundation may publish revised and/or new
versions of the
General Public License from time to time. Such new versions will be
similar in
spirit to the present version, but may differ in detail to address new
problems
or concerns.
Each version is given a distinguishing version number. If the Program
specifies
a version number of this License which applies to it and /any later
version", you
have the option of following the terms and conditions either of that
version or
of any later version published by the Free Software Foundation. If the
Program
does not specify a version number of this License, you may choose any
version
ever published by the Free Software Foundation.
10. If you wish to incorporate parts of the Program into other free
programs whose
distribution conditions are different, write to the author to ask for
permission.
For software which is copyrighted by the Free Software Foundation, write
to the
Free Software Foundation; we sometimes make exceptions for this. Our
decision
will be guided by the two goals of preserving the free status of all
derivatives of
our free software and of promoting the sharing and reuse of software
generally.
NO WARRANTY
11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE
IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMIT-
TED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED
IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
PROVIDE THE PROGRAM /AS IS" WITHOUT WARRANTY OF ANY
KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIM-
ITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO
THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH
YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORREC-
TION.
12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAWOR AGREED
TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER
PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE PROGRAM
AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, IN-
CLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUEN-
TIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA
OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED
BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO
OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER
OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES.
END OF TERMS AND CONDITIONS
D.3 Appendix: How to Apply These Terms to Your
New Programs
If you develop a new program, and you want it to be of the greatest
possible use to
the public, the best way toachieve this is to make itfree software which
everyone
can redistribute and change under these terms.
To do so, attach the following notices to the program. It is safest to
attach them
to the start of each source file to most effectively convey the
exclusion of warranty;
and each file should have at least the /copyright" line and a pointer to
where the full
notice is found.
hone line to give the program's name and a brief idea of what it does.
i
Copyright c 19yy hname of authori
This program is free software; you can redistribute it and/or modify
it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
This program is distributed in the hope that it will be useful, but
WITH-
OUT ANY WARRANTY; without even the implied warranty of MER-
CHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
the GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along
with this program; if not, write to the Free Software Foundation, Inc.,
675 Mass Ave, Cambridge, MA 02139, USA.
Also add information on how to contact you by electronic and paper
mail.
If the program is interactive, make it output a short notice like this
when it starts
in an interactive mode:
Gnomovision version 69, Copyright (C) 19yy name of author Gnomovision
comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This
is free software, and you are welcome to redistribute it under certain
conditions; type `show c' for details.
The hypothetical commands `show w' and `show c' should show the
appropriate
parts of the General Public License. Of course, the commands you use may
be called
something other than `show w' and `show c'; they could even be
mouse-clicks or
menu items{whatever suits your program.
You should also get your employer (if you work as a programmer) or
your school, if
any, to sign a /copyright disclaimer" for the program, if necessary.
Here is a sample;
alter the names:
Yoyodyne, Inc., hereby disclaims all copyright interest in the program
`Gnomovision' (which makes passes at compilers) written by James
Hacker.
hsignature of Ty Cooni, 1 April 1989 Ty Coon, President of Vice
This General Public License does not permit incorporating your program
into pro-
prietary programs. If your program is a subroutine library, you may
consider it more
useful to permit linking proprietary applications with the library. If
this is what you
want to do, use the GNU Library General Public License instead of this
License.
Glossary （名詞表）
Argument Functions and routines are passed arguments to process.
ARP Address Resolution Protocol. Used to translate IP addresses into
physical
hardware addresses.
Ascii American Standard Code for Information Interchange. Each letter of
the
alphabet is represented by an 8 bit code. Ascii is most often used to
store
written characters.
Bit A single bit of data that represents either 1 or 0 (on or off).
Bottom Half Handler Handlers for work queued within the kernel.
Byte 8 bits of data,
C A high level programming language. Most of the Linux kernel is written
in C.
CPU Central Processing Unit. The main engine of the computer, see also
micro-
processor and processor.
Data Structure This is a set of data in memory comprised of fields,
Device Driver The software controlling a particular device, for
example the NCR
810 device driver controls the NCR 810 SCSI device.
DMA Direct Memory Access.
ELF Executable and Linkable Format. This object file format designed
by the Unix
System Laboratories is now firmly established as the most commonly
used
format in Linux.
EIDE Extended IDE.
Executable image A structured file containing machine instructions and
data.
This file can be loaded into a process's virtual memory and executed.
See
also program.
Function A piece of software that performs an action. For example,
returning the
bigger of two numbers.
IDE Integrated Disk Electronics.
Image See executable image.
IP Internet Protocol.
IPC Interprocess Communiction.
Interface A standard way of calling routines and passing data
structures. For
example, the interface between two layers of code might be expressed
in terms
of routines that pass and return a particular data structure. Linux's
VFS is a
good example of an interface.
IRQ Interrupt Request Queue.
ISA Industry Standard Architecture. This is a standard, although now
rather dated,
data bus interface for system components such as oppy disk drivers.
Kernel Module A dynamically loaded kernel function such as a
filesystem or a
device driver.
Kilobyte A thousand bytes of data, often written as Kbyte,
Megabyte A million bytes of data, often written as Mbyte,
Microprocessor A very integrated CPU. Most modern CPUs are
Microprocessors.
Module A file containing CPU instructions in the form of either assembly
language
instructions or a high level language like C.
Object file A fille containing machine code and data that has not yet
been linked
with other object files or libraries to become an executable image.
Page Physical memory is divided up into equal sized pages.
Pointer A location in memory that contains the address of another
location in
memory,
Process This is an entity which can execute programs. A process could be
thought
of as a program in action.
Processor Short for Microprocessor, equivalent toCPU.
PCI Peripheral Component Interconnect. A standard describing how the
peripheral
components of a computer system may be connected together.
Peripheral An intelligent processor that does work on behalf of the
system's CPU.
For example, an IDE controller chip,
Program A coherent set of CPU instructions that performs a task, such as
printing
/hello world". See also executable image.
Protocol A protocol is a networking language used to transfer
application data
between two cooperating processes or network layers.
Register A location within a chip, used to store information or
instructions.
Routine Similar to a function except that, strictly speaking, routines
do not return
values.
SCSI Small Computer Systems Interface.
Shell This is a program which acts as an interface between the operating
system
and a human user. Also called a command shell, the most commonly used
shell
in Linux is the bash shell.
SMP Symmetrical multiprocessing. Systems with more than one processor
which
fairly share the work amongst those processors.
Socket A socket represents one end of a network connection, Linux
supports the
BSD Socket interface.
Software CPU instructions (both assembler and high level languages
like C) and
data. Mostly interchangable with Program.
System V A variant ofUnix
TM
produced in 1983, which included, amongst other
things, System V IPC mechanisms.
TCP Transmission Control Protocol.
Task Queue A mechanism for deferring work in the Linux kernel.
UDP User Datagram Protocol.
Virtual memory A hardware and software mechanism for making the
physical
memory in a system appear larger than it actually is.
Bibliography （參考書目）
[1] Richard L. Sites. Alpha Architecture Reference Manual Digital
Press
[2] Matt Welsh and Lar Kaufman. Running Linux O'Reilly & Associates,
Inc, ISBN
1-56592-100-3
[3] PCI Special Interest Group PCI Local Bus Specification
[4] PCI Special Interest Group PCI BIOS ROM Specification
[5] PCI Special Interest Group PCI to PCI Bridge Architecture
Specification
[6] Intel Peripheral Components Intel 296467, ISBN 1-55512-207-8
[7] Brian W. Kernighan and Dennis M. Richie The C Programming Language
Pren-
tice Hall, ISBN 0-13-110362-8
[8] Steven Levy Hackers Penguin, ISBN 0-14-023269-9
[9] Intel Intel486 Processor Family: Programmer's Reference Manual
Intel
[10] Comer D. E. Interworking with TCP/IP, Volume 1 - Principles,
Protocols and
Architecture Prentice Hall International Inc
[11] David Jagger ARM Architectural Reference Manual Prentice Hall, ISBN
0-13-
736299-4