3 Command Line Options for Linux/m68k
4 ===================================
6 Last Update: 2 May 1999
7 Linux/m68k version: 2.2.6
8 Author: Roman.Hodek@informatik.uni-erlangen.de (Roman Hodek)
9 Update: jds@kom.auc.dk (Jes Sorensen) and faq@linux-m68k.org (Chris Lawrence)
14 Often I've been asked which command line options the Linux/m68k
15 kernel understands, or how the exact syntax for the ... option is, or
16 ... about the option ... . I hope, this document supplies all the
19 Note that some options might be outdated, their descriptions being
20 incomplete or missing. Please update the information and send in the
24 1) Overview of the Kernel's Option Processing
25 =============================================
27 The kernel knows three kinds of options on its command line:
30 2) environment settings
33 To which of these classes an argument belongs is determined as
34 follows: If the option is known to the kernel itself, i.e. if the name
35 (the part before the '=') or, in some cases, the whole argument string
36 is known to the kernel, it belongs to class 1. Otherwise, if the
37 argument contains an '=', it is of class 2, and the definition is put
38 into init's environment. All other arguments are passed to init as
41 This document describes the valid kernel options for Linux/m68k in
42 the version mentioned at the start of this file. Later revisions may
43 add new such options, and some may be missing in older versions.
45 In general, the value (the part after the '=') of an option is a
46 list of values separated by commas. The interpretation of these values
47 is up to the driver that "owns" the option. This association of
48 options with drivers is also the reason that some are further
52 2) General Kernel Options
53 =========================
58 Syntax: root=/dev/<device>
61 This tells the kernel which device it should mount as the root
62 filesystem. The device must be a block device with a valid filesystem
65 The first syntax gives the device by name. These names are converted
66 into a major/minor number internally in the kernel in an unusual way.
67 Normally, this "conversion" is done by the device files in /dev, but
68 this isn't possible here, because the root filesystem (with /dev)
69 isn't mounted yet... So the kernel parses the name itself, with some
70 hardcoded name to number mappings. The name must always be a
71 combination of two or three letters, followed by a decimal number.
74 /dev/ram: -> 0x0100 (initial ramdisk)
75 /dev/hda: -> 0x0300 (first IDE disk)
76 /dev/hdb: -> 0x0340 (second IDE disk)
77 /dev/sda: -> 0x0800 (first SCSI disk)
78 /dev/sdb: -> 0x0810 (second SCSI disk)
79 /dev/sdc: -> 0x0820 (third SCSI disk)
80 /dev/sdd: -> 0x0830 (forth SCSI disk)
81 /dev/sde: -> 0x0840 (fifth SCSI disk)
82 /dev/fd : -> 0x0200 (floppy disk)
83 /dev/xda: -> 0x0c00 (first XT disk, unused in Linux/m68k)
84 /dev/xdb: -> 0x0c40 (second XT disk, unused in Linux/m68k)
86 The name must be followed by a decimal number, that stands for the
87 partition number. Internally, the value of the number is just
88 added to the device number mentioned in the table above. The
89 exceptions are /dev/ram and /dev/fd, where /dev/ram refers to an
90 initial ramdisk loaded by your bootstrap program (please consult the
91 instructions for your bootstrap program to find out how to load an
92 initial ramdisk). As of kernel version 2.0.18 you must specify
93 /dev/ram as the root device if you want to boot from an initial
94 ramdisk. For the floppy devices, /dev/fd, the number stands for the
95 floppy drive number (there are no partitions on floppy disks). I.e.,
96 /dev/fd0 stands for the first drive, /dev/fd1 for the second, and so
97 on. Since the number is just added, you can also force the disk format
98 by adding a number greater than 3. If you look into your /dev
99 directory, use can see the /dev/fd0D720 has major 2 and minor 16. You
100 can specify this device for the root FS by writing "root=/dev/fd16" on
101 the kernel command line.
103 [Strange and maybe uninteresting stuff ON]
105 This unusual translation of device names has some strange
106 consequences: If, for example, you have a symbolic link from /dev/fd
107 to /dev/fd0D720 as an abbreviation for floppy driver #0 in DD format,
108 you cannot use this name for specifying the root device, because the
109 kernel cannot see this symlink before mounting the root FS and it
110 isn't in the table above. If you use it, the root device will not be
111 set at all, without an error message. Another example: You cannot use a
112 partition on e.g. the sixth SCSI disk as the root filesystem, if you
113 want to specify it by name. This is, because only the devices up to
114 /dev/sde are in the table above, but not /dev/sdf. Although, you can
115 use the sixth SCSI disk for the root FS, but you have to specify the
116 device by number... (see below). Or, even more strange, you can use the
117 fact that there is no range checking of the partition number, and your
118 knowledge that each disk uses 16 minors, and write "root=/dev/sde17"
121 [Strange and maybe uninteresting stuff OFF]
123 If the device containing your root partition isn't in the table
124 above, you can also specify it by major and minor numbers. These are
125 written in hex, with no prefix and no separator between. E.g., if you
126 have a CD with contents appropriate as a root filesystem in the first
127 SCSI CD-ROM drive, you boot from it by "root=0b00". Here, hex "0b" =
128 decimal 11 is the major of SCSI CD-ROMs, and the minor 0 stands for
129 the first of these. You can find out all valid major numbers by
130 looking into include/linux/major.h.
139 These two options tell the kernel whether it should mount the root
140 filesystem read-only or read-write. The default is read-only, except
141 for ramdisks, which default to read-write.
149 This raises the kernel log level to 10 (the default is 7). This is the
150 same level as set by the "dmesg" command, just that the maximum level
151 selectable by dmesg is 8.
157 Syntax: debug=<device>
159 This option causes certain kernel messages be printed to the selected
160 debugging device. This can aid debugging the kernel, since the
161 messages can be captured and analyzed on some other machine. Which
162 devices are possible depends on the machine type. There are no checks
163 for the validity of the device name. If the device isn't implemented,
166 Messages logged this way are in general stack dumps after kernel
167 memory faults or bad kernel traps, and kernel panics. To be exact: all
168 messages of level 0 (panic messages) and all messages printed while
169 the log level is 8 or more (their level doesn't matter). Before stack
170 dumps, the kernel sets the log level to 10 automatically. A level of
171 at least 8 can also be set by the "debug" command line option (see
172 2.3) and at run time with "dmesg -n 8".
174 Devices possible for Amiga:
176 - "ser": built-in serial port; parameters: 9600bps, 8N1
177 - "mem": Save the messages to a reserved area in chip mem. After
178 rebooting, they can be read under AmigaOS with the tool
181 Devices possible for Atari:
183 - "ser1": ST-MFP serial port ("Modem1"); parameters: 9600bps, 8N1
184 - "ser2": SCC channel B serial port ("Modem2"); parameters: 9600bps, 8N1
185 - "ser" : default serial port
186 This is "ser2" for a Falcon, and "ser1" for any other machine
187 - "midi": The MIDI port; parameters: 31250bps, 8N1
188 - "par" : parallel port
189 The printing routine for this implements a timeout for the
190 case there's no printer connected (else the kernel would
191 lock up). The timeout is not exact, but usually a few
198 Syntax: ramdisk_size=<size>
200 This option instructs the kernel to set up a ramdisk of the given
201 size in KBytes. Do not use this option if the ramdisk contents are
202 passed by bootstrap! In this case, the size is selected automatically
203 and should not be overwritten.
205 The only application is for root filesystems on floppy disks, that
206 should be loaded into memory. To do that, select the corresponding
207 size of the disk as ramdisk size, and set the root device to the disk
208 drive (with "root=").
215 I can't find any sign of these options in 2.2.6.
218 3) General Device Options (Amiga and Atari)
219 ===========================================
224 Syntax: ether=[<irq>[,<base_addr>[,<mem_start>[,<mem_end>]]]],<dev-name>
226 <dev-name> is the name of a net driver, as specified in
227 drivers/net/Space.c in the Linux source. Most prominent are eth0, ...
228 eth3, sl0, ... sl3, ppp0, ..., ppp3, dummy, and lo.
230 The non-ethernet drivers (sl, ppp, dummy, lo) obviously ignore the
231 settings by this options. Also, the existing ethernet drivers for
232 Linux/m68k (ariadne, a2065, hydra) don't use them because Zorro boards
233 are really Plug-'n-Play, so the "ether=" option is useless altogether
240 Syntax: hd=<cylinders>,<heads>,<sectors>
242 This option sets the disk geometry of an IDE disk. The first hd=
243 option is for the first IDE disk, the second for the second one.
244 (I.e., you can give this option twice.) In most cases, you won't have
245 to use this option, since the kernel can obtain the geometry data
246 itself. It exists just for the case that this fails for one of your
253 Syntax: max_scsi_luns=<n>
255 Sets the maximum number of LUNs (logical units) of SCSI devices to
256 be scanned. Valid values for <n> are between 1 and 8. Default is 8 if
257 "Probe all LUNs on each SCSI device" was selected during the kernel
258 configuration, else 1.
264 Syntax: st=<buffer_size>,[<write_thres>,[<max_buffers>]]
266 Sets several parameters of the SCSI tape driver. <buffer_size> is
267 the number of 512-byte buffers reserved for tape operations for each
268 device. <write_thres> sets the number of blocks which must be filled
269 to start an actual write operation to the tape. Maximum value is the
270 total number of buffers. <max_buffer> limits the total number of
271 buffers allocated for all tape devices.
277 Syntax: dmasound=[<buffers>,<buffer-size>[,<catch-radius>]]
279 This option controls some configurations of the Linux/m68k DMA sound
280 driver (Amiga and Atari): <buffers> is the number of buffers you want
281 to use (minimum 4, default 4), <buffer-size> is the size of each
282 buffer in kilobytes (minimum 4, default 32) and <catch-radius> says
283 how much percent of error will be tolerated when setting a frequency
284 (maximum 10, default 0). For example with 3% you can play 8000Hz
285 AU-Files on the Falcon with its hardware frequency of 8195Hz and thus
286 don't need to expand the sound.
290 4) Options for Atari Only
291 =========================
296 Syntax: video=<fbname>:<sub-options...>
298 The <fbname> parameter specifies the name of the frame buffer,
299 eg. most atari users will want to specify `atafb' here. The
300 <sub-options> is a comma-separated list of the sub-options listed
303 NB: Please notice that this option was renamed from `atavideo' to
304 `video' during the development of the 1.3.x kernels, thus you
305 might need to update your boot-scripts if upgrading to 2.x from
308 NBB: The behavior of video= was changed in 2.1.57 so the recommended
309 option is to specify the name of the frame buffer.
314 This sub-option may be any of the predefined video modes, as listed
315 in atari/atafb.c in the Linux/m68k source tree. The kernel will
316 activate the given video mode at boot time and make it the default
317 mode, if the hardware allows. Currently defined names are:
320 - stmid, default5 : 640x200x2
321 - sthigh, default4: 640x400x1
322 - ttlow : 320x480x8, TT only
323 - ttmid, default1 : 640x480x4, TT only
324 - tthigh, default2: 1280x960x1, TT only
325 - vga2 : 640x480x1, Falcon only
326 - vga4 : 640x480x2, Falcon only
327 - vga16, default3 : 640x480x4, Falcon only
328 - vga256 : 640x480x8, Falcon only
329 - falh2 : 896x608x1, Falcon only
330 - falh16 : 896x608x4, Falcon only
332 If no video mode is given on the command line, the kernel tries the
333 modes names "default<n>" in turn, until one is possible with the
336 A video mode setting doesn't make sense, if the external driver is
337 activated by a "external:" sub-option.
342 Invert the display. This affects both, text (consoles) and graphics
343 (X) display. Usually, the background is chosen to be black. With this
344 option, you can make the background white.
349 Syntax: font:<fontname>
351 Specify the font to use in text modes. Currently you can choose only
352 between `VGA8x8', `VGA8x16' and `PEARL8x8'. `VGA8x8' is default, if the
353 vertical size of the display is less than 400 pixel rows. Otherwise, the
354 `VGA8x16' font is the default.
361 The number of additional lines of video memory to reserve for
362 speeding up the scrolling ("hardware scrolling"). Hardware scrolling
363 is possible only if the kernel can set the video base address in steps
364 fine enough. This is true for STE, MegaSTE, TT, and Falcon. It is not
365 possible with plain STs and graphics cards (The former because the
366 base address must be on a 256 byte boundary there, the latter because
367 the kernel doesn't know how to set the base address at all.)
369 By default, <n> is set to the number of visible text lines on the
370 display. Thus, the amount of video memory is doubled, compared to no
371 hardware scrolling. You can turn off the hardware scrolling altogether
377 Syntax: internal:<xres>;<yres>[;<xres_max>;<yres_max>;<offset>]
379 This option specifies the capabilities of some extended internal video
380 hardware, like e.g. OverScan. <xres> and <yres> give the (extended)
381 dimensions of the screen.
383 If your OverScan needs a black border, you have to write the last
384 three arguments of the "internal:". <xres_max> is the maximum line
385 length the hardware allows, <yres_max> the maximum number of lines.
386 <offset> is the offset of the visible part of the screen memory to its
387 physical start, in bytes.
389 Often, extended interval video hardware has to be activated somehow.
390 For this, see the "sw_*" options below.
396 external:<xres>;<yres>;<depth>;<org>;<scrmem>[;<scrlen>[;<vgabase>\
397 [;<colw>[;<coltype>[;<xres_virtual>]]]]]
399 [I had to break this line...]
401 This is probably the most complicated parameter... It specifies that
402 you have some external video hardware (a graphics board), and how to
403 use it under Linux/m68k. The kernel cannot know more about the hardware
404 than you tell it here! The kernel also is unable to set or change any
405 video modes, since it doesn't know about any board internal. So, you
406 have to switch to that video mode before you start Linux, and cannot
407 switch to another mode once Linux has started.
409 The first 3 parameters of this sub-option should be obvious: <xres>,
410 <yres> and <depth> give the dimensions of the screen and the number of
411 planes (depth). The depth is the logarithm to base 2 of the number
412 of colors possible. (Or, the other way round: The number of colors is
415 You have to tell the kernel furthermore how the video memory is
416 organized. This is done by a letter as <org> parameter:
418 'n': "normal planes", i.e. one whole plane after another
419 'i': "interleaved planes", i.e. 16 bit of the first plane, than 16 bit
420 of the next, and so on... This mode is used only with the
421 built-in Atari video modes, I think there is no card that
423 'p': "packed pixels", i.e. <depth> consecutive bits stand for all
424 planes of one pixel; this is the most common mode for 8 planes
425 (256 colors) on graphic cards
426 't': "true color" (more or less packed pixels, but without a color
427 lookup table); usually depth is 24
429 For monochrome modes (i.e., <depth> is 1), the <org> letter has a
432 'n': normal colors, i.e. 0=white, 1=black
433 'i': inverted colors, i.e. 0=black, 1=white
435 The next important information about the video hardware is the base
436 address of the video memory. That is given in the <scrmem> parameter,
437 as a hexadecimal number with a "0x" prefix. You have to find out this
438 address in the documentation of your hardware.
440 The next parameter, <scrlen>, tells the kernel about the size of the
441 video memory. If it's missing, the size is calculated from <xres>,
442 <yres>, and <depth>. For now, it is not useful to write a value here.
443 It would be used only for hardware scrolling (which isn't possible
444 with the external driver, because the kernel cannot set the video base
445 address), or for virtual resolutions under X (which the X server
446 doesn't support yet). So, it's currently best to leave this field
447 empty, either by ending the "external:" after the video address or by
448 writing two consecutive semicolons, if you want to give a <vgabase>
449 (it is allowed to leave this parameter empty).
451 The <vgabase> parameter is optional. If it is not given, the kernel
452 cannot read or write any color registers of the video hardware, and
453 thus you have to set appropriate colors before you start Linux. But if
454 your card is somehow VGA compatible, you can tell the kernel the base
455 address of the VGA register set, so it can change the color lookup
456 table. You have to look up this address in your board's documentation.
457 To avoid misunderstandings: <vgabase> is the _base_ address, i.e. a 4k
458 aligned address. For read/writing the color registers, the kernel
459 uses the addresses vgabase+0x3c7...vgabase+0x3c9. The <vgabase>
460 parameter is written in hexadecimal with a "0x" prefix, just as
463 <colw> is meaningful only if <vgabase> is specified. It tells the
464 kernel how wide each of the color register is, i.e. the number of bits
465 per single color (red/green/blue). Default is 6, another quite usual
468 Also <coltype> is used together with <vgabase>. It tells the kernel
469 about the color register model of your gfx board. Currently, the types
470 "vga" (which is also the default) and "mv300" (SANG MV300) are
473 Parameter <xres_virtual> is required for ProMST or ET4000 cards where
474 the physical linelength differs from the visible length. With ProMST,
475 xres_virtual must be set to 2048. For ET4000, xres_virtual depends on the
476 initialisation of the video-card.
477 If you're missing a corresponding yres_virtual: the external part is legacy,
478 therefore we don't support hardware-dependent functions like hardware-scroll,
484 The external pixel clock attached to the Falcon VIDEL shifter. This
485 currently works only with the ScreenWonder!
490 Syntax: monitorcap:<vmin>;<vmax>;<hmin>;<hmax>
492 This describes the capabilities of a multisync monitor. Don't use it
493 with a fixed-frequency monitor! For now, only the Falcon frame buffer
494 uses the settings of "monitorcap:".
496 <vmin> and <vmax> are the minimum and maximum, resp., vertical frequencies
497 your monitor can work with, in Hz. <hmin> and <hmax> are the same for
498 the horizontal frequency, in kHz.
500 The defaults are 58;62;31;32 (VGA compatible).
502 The defaults for TV/SC1224/SC1435 cover both PAL and NTSC standards.
507 If this option is given, the framebuffer device doesn't do any video
508 mode calculations and settings on its own. The only Atari fb device
509 that does this currently is the Falcon.
511 What you reach with this: Settings for unknown video extensions
512 aren't overridden by the driver, so you can still use the mode found
513 when booting, when the driver doesn't know to set this mode itself.
514 But this also means, that you can't switch video modes anymore...
516 An example where you may want to use "keep" is the ScreenBlaster for
523 Syntax: atamouse=<x-threshold>,[<y-threshold>]
525 With this option, you can set the mouse movement reporting threshold.
526 This is the number of pixels of mouse movement that have to accumulate
527 before the IKBD sends a new mouse packet to the kernel. Higher values
528 reduce the mouse interrupt load and thus reduce the chance of keyboard
529 overruns. Lower values give a slightly faster mouse responses and
530 slightly better mouse tracking.
532 You can set the threshold in x and y separately, but usually this is
533 of little practical use. If there's just one number in the option, it
534 is used for both dimensions. The default value is 2 for both
541 Syntax: ataflop=<drive type>[,<trackbuffering>[,<steprateA>[,<steprateB>]]]
543 The drive type may be 0, 1, or 2, for DD, HD, and ED, resp. This
544 setting affects how many buffers are reserved and which formats are
545 probed (see also below). The default is 1 (HD). Only one drive type
546 can be selected. If you have two disk drives, select the "better"
549 The second parameter <trackbuffer> tells the kernel whether to use
550 track buffering (1) or not (0). The default is machine-dependent:
551 no for the Medusa and yes for all others.
553 With the two following parameters, you can change the default
554 steprate used for drive A and B, resp.
560 Syntax: atascsi=<can_queue>[,<cmd_per_lun>[,<scat-gat>[,<host-id>[,<tagged>]]]]
562 This option sets some parameters for the Atari native SCSI driver.
563 Generally, any number of arguments can be omitted from the end. And
564 for each of the numbers, a negative value means "use default". The
565 defaults depend on whether TT-style or Falcon-style SCSI is used.
566 Below, defaults are noted as n/m, where the first value refers to
567 TT-SCSI and the latter to Falcon-SCSI. If an illegal value is given
568 for one parameter, an error message is printed and that one setting is
569 ignored (others aren't affected).
572 This is the maximum number of SCSI commands queued internally to the
573 Atari SCSI driver. A value of 1 effectively turns off the driver
574 internal multitasking (if it causes problems). Legal values are >=
575 1. <can_queue> can be as high as you like, but values greater than
576 <cmd_per_lun> times the number of SCSI targets (LUNs) you have
577 don't make sense. Default: 16/8.
580 Maximum number of SCSI commands issued to the driver for one
581 logical unit (LUN, usually one SCSI target). Legal values start
582 from 1. If tagged queuing (see below) is not used, values greater
583 than 2 don't make sense, but waste memory. Otherwise, the maximum
584 is the number of command tags available to the driver (currently
585 32). Default: 8/1. (Note: Values > 1 seem to cause problems on a
586 Falcon, cause not yet known.)
588 The <cmd_per_lun> value at a great part determines the amount of
589 memory SCSI reserves for itself. The formula is rather
590 complicated, but I can give you some hints:
591 no scatter-gather : cmd_per_lun * 232 bytes
592 full scatter-gather: cmd_per_lun * approx. 17 Kbytes
595 Size of the scatter-gather table, i.e. the number of requests
596 consecutive on the disk that can be merged into one SCSI command.
597 Legal values are between 0 and 255. Default: 255/0. Note: This
598 value is forced to 0 on a Falcon, since scatter-gather isn't
599 possible with the ST-DMA. Not using scatter-gather hurts
600 performance significantly.
603 The SCSI ID to be used by the initiator (your Atari). This is
604 usually 7, the highest possible ID. Every ID on the SCSI bus must
605 be unique. Default: determined at run time: If the NV-RAM checksum
606 is valid, and bit 7 in byte 30 of the NV-RAM is set, the lower 3
607 bits of this byte are used as the host ID. (This method is defined
608 by Atari and also used by some TOS HD drivers.) If the above
609 isn't given, the default ID is 7. (both, TT and Falcon).
612 0 means turn off tagged queuing support, all other values > 0 mean
613 use tagged queuing for targets that support it. Default: currently
614 off, but this may change when tagged queuing handling has been
615 proved to be reliable.
617 Tagged queuing means that more than one command can be issued to
618 one LUN, and the SCSI device itself orders the requests so they
619 can be performed in optimal order. Not all SCSI devices support
620 tagged queuing (:-().
625 Syntax: switches=<list of switches>
627 With this option you can switch some hardware lines that are often
628 used to enable/disable certain hardware extensions. Examples are
629 OverScan, overclocking, ...
631 The <list of switches> is a comma-separated list of the following
634 ikbd: set RTS of the keyboard ACIA high
635 midi: set RTS of the MIDI ACIA high
636 snd6: set bit 6 of the PSG port A
637 snd7: set bit 6 of the PSG port A
639 It doesn't make sense to mention a switch more than once (no
640 difference to only once), but you can give as many switches as you
641 want to enable different features. The switch lines are set as early
642 as possible during kernel initialization (even before determining the
645 All of the items can also be prefixed with "ov_", i.e. "ov_ikbd",
646 "ov_midi", ... These options are meant for switching on an OverScan
647 video extension. The difference to the bare option is that the
648 switch-on is done after video initialization, and somehow synchronized
649 to the HBLANK. A speciality is that ov_ikbd and ov_midi are switched
650 off before rebooting, so that OverScan is disabled and TOS boots
653 If you give an option both, with and without the "ov_" prefix, the
654 earlier initialization ("ov_"-less) takes precedence. But the
655 switching-off on reset still happens in this case.
657 5) Options for Amiga Only:
658 ==========================
663 Syntax: video=<fbname>:<sub-options...>
665 The <fbname> parameter specifies the name of the frame buffer, valid
666 options are `amifb', `cyber', 'virge', `retz3' and `clgen', provided
667 that the respective frame buffer devices have been compiled into the
668 kernel (or compiled as loadable modules). The behavior of the <fbname>
669 option was changed in 2.1.57 so it is now recommended to specify this
672 The <sub-options> is a comma-separated list of the sub-options listed
673 below. This option is organized similar to the Atari version of the
674 "video"-option (4.1), but knows fewer sub-options.
679 Again, similar to the video mode for the Atari (see 4.1.1). Predefined
680 modes depend on the used frame buffer device.
682 OCS, ECS and AGA machines all use the color frame buffer. The following
683 predefined video modes are available:
686 - ntsc : 640x200, 15 kHz, 60 Hz
687 - ntsc-lace : 640x400, 15 kHz, 60 Hz interlaced
689 - pal : 640x256, 15 kHz, 50 Hz
690 - pal-lace : 640x512, 15 kHz, 50 Hz interlaced
692 - multiscan : 640x480, 29 kHz, 57 Hz
693 - multiscan-lace : 640x960, 29 kHz, 57 Hz interlaced
694 - euro36 : 640x200, 15 kHz, 72 Hz
695 - euro36-lace : 640x400, 15 kHz, 72 Hz interlaced
696 - euro72 : 640x400, 29 kHz, 68 Hz
697 - euro72-lace : 640x800, 29 kHz, 68 Hz interlaced
698 - super72 : 800x300, 23 kHz, 70 Hz
699 - super72-lace : 800x600, 23 kHz, 70 Hz interlaced
700 - dblntsc-ff : 640x400, 27 kHz, 57 Hz
701 - dblntsc-lace : 640x800, 27 kHz, 57 Hz interlaced
702 - dblpal-ff : 640x512, 27 kHz, 47 Hz
703 - dblpal-lace : 640x1024, 27 kHz, 47 Hz interlaced
704 - dblntsc : 640x200, 27 kHz, 57 Hz doublescan
705 - dblpal : 640x256, 27 kHz, 47 Hz doublescan
707 - vga : 640x480, 31 kHz, 60 Hz
708 - vga70 : 640x400, 31 kHz, 70 Hz
710 Please notice that the ECS and VGA modes require either an ECS or AGA
711 chipset, and that these modes are limited to 2-bit color for the ECS
712 chipset and 8-bit color for the AGA chipset.
717 Syntax: depth:<nr. of bit-planes>
719 Specify the number of bit-planes for the selected video-mode.
724 Use inverted display (black on white). Functionally the same as the
725 "inverse" sub-option for the Atari.
730 Syntax: font:<fontname>
732 Specify the font to use in text modes. Functionally the same as the
733 "font" sub-option for the Atari, except that `PEARL8x8' is used instead
734 of `VGA8x8' if the vertical size of the display is less than 400 pixel
740 Syntax: monitorcap:<vmin>;<vmax>;<hmin>;<hmax>
742 This describes the capabilities of a multisync monitor. For now, only
743 the color frame buffer uses the settings of "monitorcap:".
745 <vmin> and <vmax> are the minimum and maximum, resp., vertical frequencies
746 your monitor can work with, in Hz. <hmin> and <hmax> are the same for
747 the horizontal frequency, in kHz.
749 The defaults are 50;90;15;38 (Generic Amiga multisync monitor).
755 Syntax: fd_def_df0=<value>
757 Sets the df0 value for "silent" floppy drives. The value should be in
758 hexadecimal with "0x" prefix.
764 Syntax: wd33c93=<sub-options...>
766 These options affect the A590/A2091, A3000 and GVP Series II SCSI
769 The <sub-options> is a comma-separated list of the sub-options listed
775 Syntax: nosync:bitmask
777 bitmask is a byte where the 1st 7 bits correspond with the 7
778 possible SCSI devices. Set a bit to prevent sync negotiation on that
779 device. To maintain backwards compatibility, a command-line such as
780 "wd33c93=255" will be automatically translated to
781 "wd33c93=nosync:0xff". The default is to disable sync negotiation for
782 all devices, eg. nosync:0xff.
789 `ns' is the minimum # of nanoseconds in a SCSI data transfer
790 period. Default is 500; acceptable values are 250 - 1000.
797 Specify x = 0 to never allow disconnects, 2 to always allow them.
798 x = 1 does 'adaptive' disconnects, which is the default and generally
806 If `DEBUGGING_ON' is defined, x is a bit mask that causes various
807 types of debug output to printed - see the DB_xxx defines in
815 x = clock input in MHz for WD33c93 chip. Normal values would be from
816 8 through 20. The default value depends on your hostadapter(s),
817 default for the A3000 internal controller is 14, for the A2091 it's 8
818 and for the GVP hostadapters it's either 8 or 14, depending on the
819 hostadapter and the SCSI-clock jumper present on some GVP
825 No argument. Used to separate blocks of keywords when there's more
826 than one wd33c93-based host adapter in the system.
833 If x is 1 (or if the option is just written as "nodma"), the WD33c93
834 controller will not use DMA (= direct memory access) to access the
835 Amiga's memory. This is useful for some systems (like A3000's and
836 A4000's with the A3640 accelerator, revision 3.0) that have problems
837 using DMA to chip memory. The default is 0, i.e. to use DMA if
844 Syntax: gvp11=<addr-mask>
846 The earlier versions of the GVP driver did not handle DMA
847 address-mask settings correctly which made it necessary for some
848 people to use this option, in order to get their GVP controller
849 running under Linux. These problems have hopefully been solved and the
850 use of this option is now highly unrecommended!
852 Incorrect use can lead to unpredictable behavior, so please only use
853 this option if you *know* what you are doing and have a reason to do
854 so. In any case if you experience problems and need to use this
855 option, please inform us about it by mailing to the Linux/68k kernel
858 The address mask set by this option specifies which addresses are
859 valid for DMA with the GVP Series II SCSI controller. An address is
860 valid, if no bits are set except the bits that are set in the mask,
863 Some versions of the GVP can only DMA into a 24 bit address range,
864 some can address a 25 bit address range while others can use the whole
865 32 bit address range for DMA. The correct setting depends on your
866 controller and should be autodetected by the driver. An example is the
867 24 bit region which is specified by a mask of 0x00fffffe.
870 /* Local Variables: */