The Alpha is a 64-bit general-purpose processor designed and marketed by the Digital Equipment Corporation of blessed memory, now Hewlett-Packard. The Alpha Linux project has a home page at <http://www.alphalinux.org/>.
This is the system type of your hardware. A "generic" kernel will run on any supported Alpha system. However, if you configure a kernel for your specific system, it will be faster and smaller. To find out what type of Alpha system you have, you may want to check out the Linux/Alpha FAQ, accessible on the WWW from <http://www.alphalinux.org/>. In summary: Alcor/Alpha-XLT AS 600, AS 500, XL-300, XL-366 Alpha-XL XL-233, XL-266 AlphaBook1 Alpha laptop Avanti AS 200, AS 205, AS 250, AS 255, AS 300, AS 400 Cabriolet AlphaPC64, AlphaPCI64 DP264 DP264 / DS20 / ES40 / DS10 / DS10L EB164 EB164 21164 evaluation board EB64+ EB64+ 21064 evaluation board EB66 EB66 21066 evaluation board EB66+ EB66+ 21066 evaluation board Jensen DECpc 150, DEC 2000 models 300, 500 LX164 AlphaPC164-LX Lynx AS 2100A Miata Personal Workstation 433/500/600 a/au Marvel AlphaServer ES47 / ES80 / GS1280 Mikasa AS 1000 Noname AXPpci33, UDB (Multia) Noritake AS 1000A, AS 600A, AS 800 PC164 AlphaPC164 Rawhide AS 1200, AS 4000, AS 4100 Ruffian RPX164-2, AlphaPC164-UX, AlphaPC164-BX SX164 AlphaPC164-SX Sable AS 2000, AS 2100 Shark DS 20L Takara Takara (OEM) Titan AlphaServer ES45 / DS25 / DS15 Wildfire AlphaServer GS 40/80/160/320 If you don't know what to do, choose "generic".
A generic kernel will run on all supported Alpha hardware.
For systems using the Digital ALCOR chipset: 5 chips (4, 64-bit data slices (Data Switch, DSW) - 208-pin PQFP and 1 control (Control, I/O Address, CIA) - a 383 pin plastic PGA). It provides a DRAM controller (256-bit memory bus) and a PCI interface. It also does all the work required to support an external Bcache and to maintain memory coherence when a PCI device DMAs into (or out of) memory.
XL-233 and XL-266-based Alpha systems.
Dec AlphaBook1/Burns Alpha-based laptops.
Cabriolet AlphaPC64, AlphaPCI64 systems. Derived from EB64+ but now baby-AT with Flash boot ROM, no on-board SCSI or Ethernet. 3 ISA slots, 4 PCI slots (one pair are on a shared slot), uses plug-in Bcache SIMMs. Requires power supply with 3.3V output.
Various 21264 systems with the tsunami core logic chipset. API Networks: 264DP, UP2000(+), CS20; Compaq: DS10(E,L), XP900, XP1000, DS20(E), ES40.
EB164 21164 evaluation board from DEC. Uses 21164 and ALCOR. Has ISA and PCI expansion (3 ISA slots, 2 64-bit PCI slots (one is shared with an ISA slot) and 2 32-bit PCI slots. Uses plus-in Bcache SIMMs. I/O sub-system provides SuperI/O (2S, 1P, FD), KBD, MOUSE (PS2 style), RTC/NVRAM. Boot ROM is Flash. PC-AT-sized motherboard. Requires power supply with 3.3V output.
A Digital DS group board. Uses 21066 or 21066A. I/O sub-system is identical to EB64+. Baby PC-AT size. Runs from standard PC power supply. The EB66 schematic was published as a marketing poster advertising the 21066 as "the first microprocessor in the world with embedded PCI".
Later variant of the EB66 board.
Apparently an obscure OEM single-board computer based on the Typhoon/Tsunami chipset family. Information on it is scanty.
DEC PC 150 AXP (aka Jensen): This is a very old Digital system - one of the first-generation Alpha systems. A number of these systems seem to be available on the second- hand market. The Jensen is a floor-standing tower system which originally used a 150MHz 21064 It used programmable logic to interface a 486 EISA I/O bridge to the CPU.
A technical overview of this board is available at <http://www.unix-ag.org/Linux-Alpha/Architectures/LX164.html>.
AlphaServer 2100A-based systems.
AlphaServer ES47 / ES80 / GS1280 based on EV7.
The Digital PersonalWorkStation (PWS 433a, 433au, 500a, 500au, 600a, or 600au).
AlphaServer 1000-based Alpha systems.
Alpha systems based on the AMD 751 & ALI 1543C chipsets.
AlphaServer 1000A, AlphaServer 600A, and AlphaServer 800-based systems.
AlphaServer 1200, AlphaServer 4000 and AlphaServer 4100 machines. See HOWTO at <http://www.alphalinux.org/docs/rawhide/4100_install.shtml>.
Samsung APC164UX. There is a page on known problems and workarounds at <http://www.alphalinux.org/faq/FAQ-11.html>.
Digital AlphaServer 2000 and 2100-based systems.
Alpha 11164-based OEM single-board computer.
AlphaServer ES45/DS25 SMP based on EV68 and Titan chipset.
AlphaServer GS 40/80/160/320 SMP based on the EV67 core.
Find out whether you have ISA slots on your motherboard. ISA is the name of a bus system, i.e. the way the CPU talks to the other stuff inside your box. Other bus systems are PCI, EISA, MicroChannel (MCA) or VESA. ISA is an older system, now being displaced by PCI; newer boards don't support it. If you have ISA, say Y, otherwise N.
The AXPpci33 (aka NoName), is based on the EB66 (includes the Multia UDB). This design was produced by Digital's Technical OEM (TOEM) group. It uses the 21066 processor running at 166MHz or 233MHz. It is a baby-AT size, and runs from a standard PC power supply. It has 5 ISA slots and 3 PCI slots (one pair are a shared slot). There are 2 versions, with either PS/2 or large DIN connectors for the keyboard.
Uses 21064 or 21064A and APECs. Has ISA and PCI expansion (3 ISA, 2 PCI, one pair are on a shared slot). Supports 36-bit DRAM SIMs. ISA bus generated by Intel SaturnI/O PCI-ISA bridge. On-board SCSI (NCR 810 on PCI) Ethernet (Digital 21040), KBD, MOUSE (PS2 style), SuperI/O (2S, 1P, FD), RTC/NVRAM. Boot ROM is EPROM. PC-AT size. Runs from standard PC power supply.
Say Y if you have an AS 1000 5/xxx or an AS 1000A 5/xxx.
Say Y if you have an AS 2000 5/xxx or an AS 2100 5/xxx.
Is this a machine based on the EV67 core? If in doubt, select N here and the machine will be treated as an EV6.
Avanti AS 200, AS 205, AS 250, AS 255, AS 300, and AS 400-based Alphas. Info at <http://www.unix-ag.org/Linux-Alpha/Architectures/Avanti.html>.
Support VGA on an arbitrary hose; needed for several platforms which always have multiple hoses, and whose consoles support it.
Assume the presence of special features supported by QEMU PALcode that reduce the overhead of system emulation. Generic kernels will auto-detect QEMU. But when building a system-specific kernel, the assumption is that we want to eliminate as many runtime tests as possible. If unsure, say N.
There are two different types of booting firmware on Alphas: SRM, which is command line driven, and ARC, which uses menus and arrow keys. Details about the Linux/Alpha booting process are contained in the Linux/Alpha FAQ, accessible on the WWW from <http://www.alphalinux.org/>. The usual way to load Linux on an Alpha machine is to use MILO (a bootloader that lets you pass command line parameters to the kernel just like lilo does for the x86 architecture) which can be loaded either from ARC or can be installed directly as a permanent firmware replacement from floppy (which requires changing a certain jumper on the motherboard). If you want to do either of these, say N here. If MILO doesn't work on your system (true for Jensen motherboards), you can bypass it altogether and boot Linux directly from an SRM console; say Y here in order to do that. Note that you won't be able to boot from an IDE disk using SRM. If unsure, say N.
This enables support for systems with more than one CPU. If you have a system with only one CPU, say N. If you have a system with more than one CPU, say Y. If you say N here, the kernel will run on uni- and multiprocessor machines, but will use only one CPU of a multiprocessor machine. If you say Y here, the kernel will run on many, but not all, uniprocessor machines. On a uniprocessor machine, the kernel will run faster if you say N here. See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>. If you don't know what to do here, say N.
MARVEL support can handle a maximum of 32 CPUs, all the others with working support have a maximum of 4 CPUs.
Say Y to support efficient handling of discontiguous physical memory, for architectures which are either NUMA (Non-Uniform Memory Access) or have huge holes in the physical address space for other reasons. See <file:Documentation/vm/numa.rst> for more.
Say Y to support efficient handling of discontiguous physical memory, for systems that have huge holes in the physical address space.
Say Y to compile the kernel to support NUMA (Non-Uniform Memory Access). This option is for configuring high-end multiprocessor server machines. If in doubt, say N.
The Wait for Interrupt (WTINT) PALcall attempts to place the CPU to sleep until the next interrupt. This may reduce the power consumed, and the heat produced by the computer. However, it has the side effect of making the cycle counter unreliable as a timing device across the sleep. For emulation under QEMU, definitely say Y here, as we have other mechanisms for measuring time than the cycle counter. For EV4 (but not LCA), EV5 and EV56 systems, or for systems running MILO, sleep mode is not supported so you might as well say N here. For SMP systems we cannot use the cycle counter for timing anyway, so you might as well say Y here. If unsure, say N.
Process creation and other aspects of virtual memory management can be streamlined if we restrict the kernel to one PGD for all vmalloc allocations. This equates to about 8GB. Under normal circumstances, this is so far and above what is needed as to be laughable. However, there are certain applications (such as benchmark-grade in-kernel web serving) that can make use of as much vmalloc space as is available. Say N unless you know you need gobs and gobs of vmalloc space.
This option allows the default printing mode to be set, and then possibly overridden by a boot command argument. For example, if one wanted the option of printing verbose machine checks, but wanted the default to be as if verbose machine check printing was turned off, then one would choose the printing mode to be 0. Then, upon reboot, one could add the boot command line "verbose_mcheck=1" to get the normal verbose machine check printing, or "verbose_mcheck=2" to get the maximum information available. Take the default (1) unless you want more control or more info.
The frequency at which timer interrupts occur. A high frequency minimizes latency, whereas a low frequency minimizes overhead of process accounting. The later effect is especially significant when being run under QEMU. Note that some Alpha hardware cannot change the interrupt frequency of the timer. If unsure, say 1024 (or 1200 for Rawhide). config HZ_32 bool "32 Hz" config HZ_64 bool "64 Hz" config HZ_128 bool "128 Hz" config HZ_256 bool "256 Hz" config HZ_1024 bool "1024 Hz" config HZ_1200 bool "1200 Hz"
If you enable this option, a subdirectory inside /proc called /proc/srm_environment will give you access to the all important SRM environment variables (those which have a name) and also to all others (by their internal number). SRM is something like a BIOS for Alpha machines. There are some other such BIOSes, like AlphaBIOS, which this driver cannot support (hey, that's not SRM!). Despite the fact that this driver doesn't work on all Alphas (but only on those which have SRM as their firmware), it's save to build it even if your particular machine doesn't know about SRM (or if you intend to compile a generic kernel). It will simply not create those subdirectory in /proc (and give you some warning, of course). This driver is also available as a module and will be called srm_env then.