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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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tree | a94efe259b9009378be6d90eb30d2b019d95c194 /Documentation/m68k/kernel-options.rst | |
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Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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diff --git a/Documentation/m68k/kernel-options.rst b/Documentation/m68k/kernel-options.rst new file mode 100644 index 000000000..cabd94197 --- /dev/null +++ b/Documentation/m68k/kernel-options.rst @@ -0,0 +1,911 @@ +=================================== +Command Line Options for Linux/m68k +=================================== + +Last Update: 2 May 1999 + +Linux/m68k version: 2.2.6 + +Author: Roman.Hodek@informatik.uni-erlangen.de (Roman Hodek) + +Update: jds@kom.auc.dk (Jes Sorensen) and faq@linux-m68k.org (Chris Lawrence) + +0) Introduction +=============== + +Often I've been asked which command line options the Linux/m68k +kernel understands, or how the exact syntax for the ... option is, or +... about the option ... . I hope, this document supplies all the +answers... + +Note that some options might be outdated, their descriptions being +incomplete or missing. Please update the information and send in the +patches. + + +1) Overview of the Kernel's Option Processing +============================================= + +The kernel knows three kinds of options on its command line: + + 1) kernel options + 2) environment settings + 3) arguments for init + +To which of these classes an argument belongs is determined as +follows: If the option is known to the kernel itself, i.e. if the name +(the part before the '=') or, in some cases, the whole argument string +is known to the kernel, it belongs to class 1. Otherwise, if the +argument contains an '=', it is of class 2, and the definition is put +into init's environment. All other arguments are passed to init as +command line options. + +This document describes the valid kernel options for Linux/m68k in +the version mentioned at the start of this file. Later revisions may +add new such options, and some may be missing in older versions. + +In general, the value (the part after the '=') of an option is a +list of values separated by commas. The interpretation of these values +is up to the driver that "owns" the option. This association of +options with drivers is also the reason that some are further +subdivided. + + +2) General Kernel Options +========================= + +2.1) root= +---------- + +:Syntax: root=/dev/<device> +:or: root=<hex_number> + +This tells the kernel which device it should mount as the root +filesystem. The device must be a block device with a valid filesystem +on it. + +The first syntax gives the device by name. These names are converted +into a major/minor number internally in the kernel in an unusual way. +Normally, this "conversion" is done by the device files in /dev, but +this isn't possible here, because the root filesystem (with /dev) +isn't mounted yet... So the kernel parses the name itself, with some +hardcoded name to number mappings. The name must always be a +combination of two or three letters, followed by a decimal number. +Valid names are:: + + /dev/ram: -> 0x0100 (initial ramdisk) + /dev/hda: -> 0x0300 (first IDE disk) + /dev/hdb: -> 0x0340 (second IDE disk) + /dev/sda: -> 0x0800 (first SCSI disk) + /dev/sdb: -> 0x0810 (second SCSI disk) + /dev/sdc: -> 0x0820 (third SCSI disk) + /dev/sdd: -> 0x0830 (forth SCSI disk) + /dev/sde: -> 0x0840 (fifth SCSI disk) + /dev/fd : -> 0x0200 (floppy disk) + +The name must be followed by a decimal number, that stands for the +partition number. Internally, the value of the number is just +added to the device number mentioned in the table above. The +exceptions are /dev/ram and /dev/fd, where /dev/ram refers to an +initial ramdisk loaded by your bootstrap program (please consult the +instructions for your bootstrap program to find out how to load an +initial ramdisk). As of kernel version 2.0.18 you must specify +/dev/ram as the root device if you want to boot from an initial +ramdisk. For the floppy devices, /dev/fd, the number stands for the +floppy drive number (there are no partitions on floppy disks). I.e., +/dev/fd0 stands for the first drive, /dev/fd1 for the second, and so +on. Since the number is just added, you can also force the disk format +by adding a number greater than 3. If you look into your /dev +directory, use can see the /dev/fd0D720 has major 2 and minor 16. You +can specify this device for the root FS by writing "root=/dev/fd16" on +the kernel command line. + +[Strange and maybe uninteresting stuff ON] + +This unusual translation of device names has some strange +consequences: If, for example, you have a symbolic link from /dev/fd +to /dev/fd0D720 as an abbreviation for floppy driver #0 in DD format, +you cannot use this name for specifying the root device, because the +kernel cannot see this symlink before mounting the root FS and it +isn't in the table above. If you use it, the root device will not be +set at all, without an error message. Another example: You cannot use a +partition on e.g. the sixth SCSI disk as the root filesystem, if you +want to specify it by name. This is, because only the devices up to +/dev/sde are in the table above, but not /dev/sdf. Although, you can +use the sixth SCSI disk for the root FS, but you have to specify the +device by number... (see below). Or, even more strange, you can use the +fact that there is no range checking of the partition number, and your +knowledge that each disk uses 16 minors, and write "root=/dev/sde17" +(for /dev/sdf1). + +[Strange and maybe uninteresting stuff OFF] + +If the device containing your root partition isn't in the table +above, you can also specify it by major and minor numbers. These are +written in hex, with no prefix and no separator between. E.g., if you +have a CD with contents appropriate as a root filesystem in the first +SCSI CD-ROM drive, you boot from it by "root=0b00". Here, hex "0b" = +decimal 11 is the major of SCSI CD-ROMs, and the minor 0 stands for +the first of these. You can find out all valid major numbers by +looking into include/linux/major.h. + +In addition to major and minor numbers, if the device containing your +root partition uses a partition table format with unique partition +identifiers, then you may use them. For instance, +"root=PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF". It is also +possible to reference another partition on the same device using a +known partition UUID as the starting point. For example, +if partition 5 of the device has the UUID of +00112233-4455-6677-8899-AABBCCDDEEFF then partition 3 may be found as +follows: + + PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF/PARTNROFF=-2 + +Authoritative information can be found in +"Documentation/admin-guide/kernel-parameters.rst". + + +2.2) ro, rw +----------- + +:Syntax: ro +:or: rw + +These two options tell the kernel whether it should mount the root +filesystem read-only or read-write. The default is read-only, except +for ramdisks, which default to read-write. + + +2.3) debug +---------- + +:Syntax: debug + +This raises the kernel log level to 10 (the default is 7). This is the +same level as set by the "dmesg" command, just that the maximum level +selectable by dmesg is 8. + + +2.4) debug= +----------- + +:Syntax: debug=<device> + +This option causes certain kernel messages be printed to the selected +debugging device. This can aid debugging the kernel, since the +messages can be captured and analyzed on some other machine. Which +devices are possible depends on the machine type. There are no checks +for the validity of the device name. If the device isn't implemented, +nothing happens. + +Messages logged this way are in general stack dumps after kernel +memory faults or bad kernel traps, and kernel panics. To be exact: all +messages of level 0 (panic messages) and all messages printed while +the log level is 8 or more (their level doesn't matter). Before stack +dumps, the kernel sets the log level to 10 automatically. A level of +at least 8 can also be set by the "debug" command line option (see +2.3) and at run time with "dmesg -n 8". + +Devices possible for Amiga: + + - "ser": + built-in serial port; parameters: 9600bps, 8N1 + - "mem": + Save the messages to a reserved area in chip mem. After + rebooting, they can be read under AmigaOS with the tool + 'dmesg'. + +Devices possible for Atari: + + - "ser1": + ST-MFP serial port ("Modem1"); parameters: 9600bps, 8N1 + - "ser2": + SCC channel B serial port ("Modem2"); parameters: 9600bps, 8N1 + - "ser" : + default serial port + This is "ser2" for a Falcon, and "ser1" for any other machine + - "midi": + The MIDI port; parameters: 31250bps, 8N1 + - "par" : + parallel port + + The printing routine for this implements a timeout for the + case there's no printer connected (else the kernel would + lock up). The timeout is not exact, but usually a few + seconds. + + +2.6) ramdisk_size= +------------------ + +:Syntax: ramdisk_size=<size> + +This option instructs the kernel to set up a ramdisk of the given +size in KBytes. Do not use this option if the ramdisk contents are +passed by bootstrap! In this case, the size is selected automatically +and should not be overwritten. + +The only application is for root filesystems on floppy disks, that +should be loaded into memory. To do that, select the corresponding +size of the disk as ramdisk size, and set the root device to the disk +drive (with "root="). + + +2.7) swap= + + I can't find any sign of this option in 2.2.6. + +2.8) buff= +----------- + + I can't find any sign of this option in 2.2.6. + + +3) General Device Options (Amiga and Atari) +=========================================== + +3.1) ether= +----------- + +:Syntax: ether=[<irq>[,<base_addr>[,<mem_start>[,<mem_end>]]]],<dev-name> + +<dev-name> is the name of a net driver, as specified in +drivers/net/Space.c in the Linux source. Most prominent are eth0, ... +eth3, sl0, ... sl3, ppp0, ..., ppp3, dummy, and lo. + +The non-ethernet drivers (sl, ppp, dummy, lo) obviously ignore the +settings by this options. Also, the existing ethernet drivers for +Linux/m68k (ariadne, a2065, hydra) don't use them because Zorro boards +are really Plug-'n-Play, so the "ether=" option is useless altogether +for Linux/m68k. + + +3.2) hd= +-------- + +:Syntax: hd=<cylinders>,<heads>,<sectors> + +This option sets the disk geometry of an IDE disk. The first hd= +option is for the first IDE disk, the second for the second one. +(I.e., you can give this option twice.) In most cases, you won't have +to use this option, since the kernel can obtain the geometry data +itself. It exists just for the case that this fails for one of your +disks. + + +3.3) max_scsi_luns= +------------------- + +:Syntax: max_scsi_luns=<n> + +Sets the maximum number of LUNs (logical units) of SCSI devices to +be scanned. Valid values for <n> are between 1 and 8. Default is 8 if +"Probe all LUNs on each SCSI device" was selected during the kernel +configuration, else 1. + + +3.4) st= +-------- + +:Syntax: st=<buffer_size>,[<write_thres>,[<max_buffers>]] + +Sets several parameters of the SCSI tape driver. <buffer_size> is +the number of 512-byte buffers reserved for tape operations for each +device. <write_thres> sets the number of blocks which must be filled +to start an actual write operation to the tape. Maximum value is the +total number of buffers. <max_buffer> limits the total number of +buffers allocated for all tape devices. + + +3.5) dmasound= +-------------- + +:Syntax: dmasound=[<buffers>,<buffer-size>[,<catch-radius>]] + +This option controls some configurations of the Linux/m68k DMA sound +driver (Amiga and Atari): <buffers> is the number of buffers you want +to use (minimum 4, default 4), <buffer-size> is the size of each +buffer in kilobytes (minimum 4, default 32) and <catch-radius> says +how much percent of error will be tolerated when setting a frequency +(maximum 10, default 0). For example with 3% you can play 8000Hz +AU-Files on the Falcon with its hardware frequency of 8195Hz and thus +don't need to expand the sound. + + + +4) Options for Atari Only +========================= + +4.1) video= +----------- + +:Syntax: video=<fbname>:<sub-options...> + +The <fbname> parameter specifies the name of the frame buffer, +eg. most atari users will want to specify `atafb` here. The +<sub-options> is a comma-separated list of the sub-options listed +below. + +NB: + Please notice that this option was renamed from `atavideo` to + `video` during the development of the 1.3.x kernels, thus you + might need to update your boot-scripts if upgrading to 2.x from + an 1.2.x kernel. + +NBB: + The behavior of video= was changed in 2.1.57 so the recommended + option is to specify the name of the frame buffer. + +4.1.1) Video Mode +----------------- + +This sub-option may be any of the predefined video modes, as listed +in atari/atafb.c in the Linux/m68k source tree. The kernel will +activate the given video mode at boot time and make it the default +mode, if the hardware allows. Currently defined names are: + + - stlow : 320x200x4 + - stmid, default5 : 640x200x2 + - sthigh, default4: 640x400x1 + - ttlow : 320x480x8, TT only + - ttmid, default1 : 640x480x4, TT only + - tthigh, default2: 1280x960x1, TT only + - vga2 : 640x480x1, Falcon only + - vga4 : 640x480x2, Falcon only + - vga16, default3 : 640x480x4, Falcon only + - vga256 : 640x480x8, Falcon only + - falh2 : 896x608x1, Falcon only + - falh16 : 896x608x4, Falcon only + +If no video mode is given on the command line, the kernel tries the +modes names "default<n>" in turn, until one is possible with the +hardware in use. + +A video mode setting doesn't make sense, if the external driver is +activated by a "external:" sub-option. + +4.1.2) inverse +-------------- + +Invert the display. This affects both, text (consoles) and graphics +(X) display. Usually, the background is chosen to be black. With this +option, you can make the background white. + +4.1.3) font +----------- + +:Syntax: font:<fontname> + +Specify the font to use in text modes. Currently you can choose only +between `VGA8x8`, `VGA8x16` and `PEARL8x8`. `VGA8x8` is default, if the +vertical size of the display is less than 400 pixel rows. Otherwise, the +`VGA8x16` font is the default. + +4.1.4) `hwscroll_` +------------------ + +:Syntax: `hwscroll_<n>` + +The number of additional lines of video memory to reserve for +speeding up the scrolling ("hardware scrolling"). Hardware scrolling +is possible only if the kernel can set the video base address in steps +fine enough. This is true for STE, MegaSTE, TT, and Falcon. It is not +possible with plain STs and graphics cards (The former because the +base address must be on a 256 byte boundary there, the latter because +the kernel doesn't know how to set the base address at all.) + +By default, <n> is set to the number of visible text lines on the +display. Thus, the amount of video memory is doubled, compared to no +hardware scrolling. You can turn off the hardware scrolling altogether +by setting <n> to 0. + +4.1.5) internal: +---------------- + +:Syntax: internal:<xres>;<yres>[;<xres_max>;<yres_max>;<offset>] + +This option specifies the capabilities of some extended internal video +hardware, like e.g. OverScan. <xres> and <yres> give the (extended) +dimensions of the screen. + +If your OverScan needs a black border, you have to write the last +three arguments of the "internal:". <xres_max> is the maximum line +length the hardware allows, <yres_max> the maximum number of lines. +<offset> is the offset of the visible part of the screen memory to its +physical start, in bytes. + +Often, extended interval video hardware has to be activated somehow. +For this, see the "sw_*" options below. + +4.1.6) external: +---------------- + +:Syntax: + external:<xres>;<yres>;<depth>;<org>;<scrmem>[;<scrlen>[;<vgabase> + [;<colw>[;<coltype>[;<xres_virtual>]]]]] + +.. I had to break this line... + +This is probably the most complicated parameter... It specifies that +you have some external video hardware (a graphics board), and how to +use it under Linux/m68k. The kernel cannot know more about the hardware +than you tell it here! The kernel also is unable to set or change any +video modes, since it doesn't know about any board internal. So, you +have to switch to that video mode before you start Linux, and cannot +switch to another mode once Linux has started. + +The first 3 parameters of this sub-option should be obvious: <xres>, +<yres> and <depth> give the dimensions of the screen and the number of +planes (depth). The depth is the logarithm to base 2 of the number +of colors possible. (Or, the other way round: The number of colors is +2^depth). + +You have to tell the kernel furthermore how the video memory is +organized. This is done by a letter as <org> parameter: + + 'n': + "normal planes", i.e. one whole plane after another + 'i': + "interleaved planes", i.e. 16 bit of the first plane, than 16 bit + of the next, and so on... This mode is used only with the + built-in Atari video modes, I think there is no card that + supports this mode. + 'p': + "packed pixels", i.e. <depth> consecutive bits stand for all + planes of one pixel; this is the most common mode for 8 planes + (256 colors) on graphic cards + 't': + "true color" (more or less packed pixels, but without a color + lookup table); usually depth is 24 + +For monochrome modes (i.e., <depth> is 1), the <org> letter has a +different meaning: + + 'n': + normal colors, i.e. 0=white, 1=black + 'i': + inverted colors, i.e. 0=black, 1=white + +The next important information about the video hardware is the base +address of the video memory. That is given in the <scrmem> parameter, +as a hexadecimal number with a "0x" prefix. You have to find out this +address in the documentation of your hardware. + +The next parameter, <scrlen>, tells the kernel about the size of the +video memory. If it's missing, the size is calculated from <xres>, +<yres>, and <depth>. For now, it is not useful to write a value here. +It would be used only for hardware scrolling (which isn't possible +with the external driver, because the kernel cannot set the video base +address), or for virtual resolutions under X (which the X server +doesn't support yet). So, it's currently best to leave this field +empty, either by ending the "external:" after the video address or by +writing two consecutive semicolons, if you want to give a <vgabase> +(it is allowed to leave this parameter empty). + +The <vgabase> parameter is optional. If it is not given, the kernel +cannot read or write any color registers of the video hardware, and +thus you have to set appropriate colors before you start Linux. But if +your card is somehow VGA compatible, you can tell the kernel the base +address of the VGA register set, so it can change the color lookup +table. You have to look up this address in your board's documentation. +To avoid misunderstandings: <vgabase> is the _base_ address, i.e. a 4k +aligned address. For read/writing the color registers, the kernel +uses the addresses vgabase+0x3c7...vgabase+0x3c9. The <vgabase> +parameter is written in hexadecimal with a "0x" prefix, just as +<scrmem>. + +<colw> is meaningful only if <vgabase> is specified. It tells the +kernel how wide each of the color register is, i.e. the number of bits +per single color (red/green/blue). Default is 6, another quite usual +value is 8. + +Also <coltype> is used together with <vgabase>. It tells the kernel +about the color register model of your gfx board. Currently, the types +"vga" (which is also the default) and "mv300" (SANG MV300) are +implemented. + +Parameter <xres_virtual> is required for ProMST or ET4000 cards where +the physical linelength differs from the visible length. With ProMST, +xres_virtual must be set to 2048. For ET4000, xres_virtual depends on the +initialisation of the video-card. +If you're missing a corresponding yres_virtual: the external part is legacy, +therefore we don't support hardware-dependent functions like hardware-scroll, +panning or blanking. + +4.1.7) eclock: +-------------- + +The external pixel clock attached to the Falcon VIDEL shifter. This +currently works only with the ScreenWonder! + +4.1.8) monitorcap: +------------------- + +:Syntax: monitorcap:<vmin>;<vmax>;<hmin>;<hmax> + +This describes the capabilities of a multisync monitor. Don't use it +with a fixed-frequency monitor! For now, only the Falcon frame buffer +uses the settings of "monitorcap:". + +<vmin> and <vmax> are the minimum and maximum, resp., vertical frequencies +your monitor can work with, in Hz. <hmin> and <hmax> are the same for +the horizontal frequency, in kHz. + + The defaults are 58;62;31;32 (VGA compatible). + + The defaults for TV/SC1224/SC1435 cover both PAL and NTSC standards. + +4.1.9) keep +------------ + +If this option is given, the framebuffer device doesn't do any video +mode calculations and settings on its own. The only Atari fb device +that does this currently is the Falcon. + +What you reach with this: Settings for unknown video extensions +aren't overridden by the driver, so you can still use the mode found +when booting, when the driver doesn't know to set this mode itself. +But this also means, that you can't switch video modes anymore... + +An example where you may want to use "keep" is the ScreenBlaster for +the Falcon. + + +4.2) atamouse= +-------------- + +:Syntax: atamouse=<x-threshold>,[<y-threshold>] + +With this option, you can set the mouse movement reporting threshold. +This is the number of pixels of mouse movement that have to accumulate +before the IKBD sends a new mouse packet to the kernel. Higher values +reduce the mouse interrupt load and thus reduce the chance of keyboard +overruns. Lower values give a slightly faster mouse responses and +slightly better mouse tracking. + +You can set the threshold in x and y separately, but usually this is +of little practical use. If there's just one number in the option, it +is used for both dimensions. The default value is 2 for both +thresholds. + + +4.3) ataflop= +------------- + +:Syntax: ataflop=<drive type>[,<trackbuffering>[,<steprateA>[,<steprateB>]]] + + The drive type may be 0, 1, or 2, for DD, HD, and ED, resp. This + setting affects how many buffers are reserved and which formats are + probed (see also below). The default is 1 (HD). Only one drive type + can be selected. If you have two disk drives, select the "better" + type. + + The second parameter <trackbuffer> tells the kernel whether to use + track buffering (1) or not (0). The default is machine-dependent: + no for the Medusa and yes for all others. + + With the two following parameters, you can change the default + steprate used for drive A and B, resp. + + +4.4) atascsi= +------------- + +:Syntax: atascsi=<can_queue>[,<cmd_per_lun>[,<scat-gat>[,<host-id>[,<tagged>]]]] + +This option sets some parameters for the Atari native SCSI driver. +Generally, any number of arguments can be omitted from the end. And +for each of the numbers, a negative value means "use default". The +defaults depend on whether TT-style or Falcon-style SCSI is used. +Below, defaults are noted as n/m, where the first value refers to +TT-SCSI and the latter to Falcon-SCSI. If an illegal value is given +for one parameter, an error message is printed and that one setting is +ignored (others aren't affected). + + <can_queue>: + This is the maximum number of SCSI commands queued internally to the + Atari SCSI driver. A value of 1 effectively turns off the driver + internal multitasking (if it causes problems). Legal values are >= + 1. <can_queue> can be as high as you like, but values greater than + <cmd_per_lun> times the number of SCSI targets (LUNs) you have + don't make sense. Default: 16/8. + + <cmd_per_lun>: + Maximum number of SCSI commands issued to the driver for one + logical unit (LUN, usually one SCSI target). Legal values start + from 1. If tagged queuing (see below) is not used, values greater + than 2 don't make sense, but waste memory. Otherwise, the maximum + is the number of command tags available to the driver (currently + 32). Default: 8/1. (Note: Values > 1 seem to cause problems on a + Falcon, cause not yet known.) + + The <cmd_per_lun> value at a great part determines the amount of + memory SCSI reserves for itself. The formula is rather + complicated, but I can give you some hints: + + no scatter-gather: + cmd_per_lun * 232 bytes + full scatter-gather: + cmd_per_lun * approx. 17 Kbytes + + <scat-gat>: + Size of the scatter-gather table, i.e. the number of requests + consecutive on the disk that can be merged into one SCSI command. + Legal values are between 0 and 255. Default: 255/0. Note: This + value is forced to 0 on a Falcon, since scatter-gather isn't + possible with the ST-DMA. Not using scatter-gather hurts + performance significantly. + + <host-id>: + The SCSI ID to be used by the initiator (your Atari). This is + usually 7, the highest possible ID. Every ID on the SCSI bus must + be unique. Default: determined at run time: If the NV-RAM checksum + is valid, and bit 7 in byte 30 of the NV-RAM is set, the lower 3 + bits of this byte are used as the host ID. (This method is defined + by Atari and also used by some TOS HD drivers.) If the above + isn't given, the default ID is 7. (both, TT and Falcon). + + <tagged>: + 0 means turn off tagged queuing support, all other values > 0 mean + use tagged queuing for targets that support it. Default: currently + off, but this may change when tagged queuing handling has been + proved to be reliable. + + Tagged queuing means that more than one command can be issued to + one LUN, and the SCSI device itself orders the requests so they + can be performed in optimal order. Not all SCSI devices support + tagged queuing (:-(). + +4.5 switches= +------------- + +:Syntax: switches=<list of switches> + +With this option you can switch some hardware lines that are often +used to enable/disable certain hardware extensions. Examples are +OverScan, overclocking, ... + +The <list of switches> is a comma-separated list of the following +items: + + ikbd: + set RTS of the keyboard ACIA high + midi: + set RTS of the MIDI ACIA high + snd6: + set bit 6 of the PSG port A + snd7: + set bit 6 of the PSG port A + +It doesn't make sense to mention a switch more than once (no +difference to only once), but you can give as many switches as you +want to enable different features. The switch lines are set as early +as possible during kernel initialization (even before determining the +present hardware.) + +All of the items can also be prefixed with `ov_`, i.e. `ov_ikbd`, +`ov_midi`, ... These options are meant for switching on an OverScan +video extension. The difference to the bare option is that the +switch-on is done after video initialization, and somehow synchronized +to the HBLANK. A speciality is that ov_ikbd and ov_midi are switched +off before rebooting, so that OverScan is disabled and TOS boots +correctly. + +If you give an option both, with and without the `ov_` prefix, the +earlier initialization (`ov_`-less) takes precedence. But the +switching-off on reset still happens in this case. + +5) Options for Amiga Only: +========================== + +5.1) video= +----------- + +:Syntax: video=<fbname>:<sub-options...> + +The <fbname> parameter specifies the name of the frame buffer, valid +options are `amifb`, `cyber`, 'virge', `retz3` and `clgen`, provided +that the respective frame buffer devices have been compiled into the +kernel (or compiled as loadable modules). The behavior of the <fbname> +option was changed in 2.1.57 so it is now recommended to specify this +option. + +The <sub-options> is a comma-separated list of the sub-options listed +below. This option is organized similar to the Atari version of the +"video"-option (4.1), but knows fewer sub-options. + +5.1.1) video mode +----------------- + +Again, similar to the video mode for the Atari (see 4.1.1). Predefined +modes depend on the used frame buffer device. + +OCS, ECS and AGA machines all use the color frame buffer. The following +predefined video modes are available: + +NTSC modes: + - ntsc : 640x200, 15 kHz, 60 Hz + - ntsc-lace : 640x400, 15 kHz, 60 Hz interlaced + +PAL modes: + - pal : 640x256, 15 kHz, 50 Hz + - pal-lace : 640x512, 15 kHz, 50 Hz interlaced + +ECS modes: + - multiscan : 640x480, 29 kHz, 57 Hz + - multiscan-lace : 640x960, 29 kHz, 57 Hz interlaced + - euro36 : 640x200, 15 kHz, 72 Hz + - euro36-lace : 640x400, 15 kHz, 72 Hz interlaced + - euro72 : 640x400, 29 kHz, 68 Hz + - euro72-lace : 640x800, 29 kHz, 68 Hz interlaced + - super72 : 800x300, 23 kHz, 70 Hz + - super72-lace : 800x600, 23 kHz, 70 Hz interlaced + - dblntsc-ff : 640x400, 27 kHz, 57 Hz + - dblntsc-lace : 640x800, 27 kHz, 57 Hz interlaced + - dblpal-ff : 640x512, 27 kHz, 47 Hz + - dblpal-lace : 640x1024, 27 kHz, 47 Hz interlaced + - dblntsc : 640x200, 27 kHz, 57 Hz doublescan + - dblpal : 640x256, 27 kHz, 47 Hz doublescan + +VGA modes: + - vga : 640x480, 31 kHz, 60 Hz + - vga70 : 640x400, 31 kHz, 70 Hz + +Please notice that the ECS and VGA modes require either an ECS or AGA +chipset, and that these modes are limited to 2-bit color for the ECS +chipset and 8-bit color for the AGA chipset. + +5.1.2) depth +------------ + +:Syntax: depth:<nr. of bit-planes> + +Specify the number of bit-planes for the selected video-mode. + +5.1.3) inverse +-------------- + +Use inverted display (black on white). Functionally the same as the +"inverse" sub-option for the Atari. + +5.1.4) font +----------- + +:Syntax: font:<fontname> + +Specify the font to use in text modes. Functionally the same as the +"font" sub-option for the Atari, except that `PEARL8x8` is used instead +of `VGA8x8` if the vertical size of the display is less than 400 pixel +rows. + +5.1.5) monitorcap: +------------------- + +:Syntax: monitorcap:<vmin>;<vmax>;<hmin>;<hmax> + +This describes the capabilities of a multisync monitor. For now, only +the color frame buffer uses the settings of "monitorcap:". + +<vmin> and <vmax> are the minimum and maximum, resp., vertical frequencies +your monitor can work with, in Hz. <hmin> and <hmax> are the same for +the horizontal frequency, in kHz. + +The defaults are 50;90;15;38 (Generic Amiga multisync monitor). + + +5.2) fd_def_df0= +---------------- + +:Syntax: fd_def_df0=<value> + +Sets the df0 value for "silent" floppy drives. The value should be in +hexadecimal with "0x" prefix. + + +5.3) wd33c93= +------------- + +:Syntax: wd33c93=<sub-options...> + +These options affect the A590/A2091, A3000 and GVP Series II SCSI +controllers. + +The <sub-options> is a comma-separated list of the sub-options listed +below. + +5.3.1) nosync +------------- + +:Syntax: nosync:bitmask + +bitmask is a byte where the 1st 7 bits correspond with the 7 +possible SCSI devices. Set a bit to prevent sync negotiation on that +device. To maintain backwards compatibility, a command-line such as +"wd33c93=255" will be automatically translated to +"wd33c93=nosync:0xff". The default is to disable sync negotiation for +all devices, eg. nosync:0xff. + +5.3.2) period +------------- + +:Syntax: period:ns + +`ns` is the minimum # of nanoseconds in a SCSI data transfer +period. Default is 500; acceptable values are 250 - 1000. + +5.3.3) disconnect +----------------- + +:Syntax: disconnect:x + +Specify x = 0 to never allow disconnects, 2 to always allow them. +x = 1 does 'adaptive' disconnects, which is the default and generally +the best choice. + +5.3.4) debug +------------ + +:Syntax: debug:x + +If `DEBUGGING_ON` is defined, x is a bit mask that causes various +types of debug output to printed - see the DB_xxx defines in +wd33c93.h. + +5.3.5) clock +------------ + +:Syntax: clock:x + +x = clock input in MHz for WD33c93 chip. Normal values would be from +8 through 20. The default value depends on your hostadapter(s), +default for the A3000 internal controller is 14, for the A2091 it's 8 +and for the GVP hostadapters it's either 8 or 14, depending on the +hostadapter and the SCSI-clock jumper present on some GVP +hostadapters. + +5.3.6) next +----------- + +No argument. Used to separate blocks of keywords when there's more +than one wd33c93-based host adapter in the system. + +5.3.7) nodma +------------ + +:Syntax: nodma:x + +If x is 1 (or if the option is just written as "nodma"), the WD33c93 +controller will not use DMA (= direct memory access) to access the +Amiga's memory. This is useful for some systems (like A3000's and +A4000's with the A3640 accelerator, revision 3.0) that have problems +using DMA to chip memory. The default is 0, i.e. to use DMA if +possible. + + +5.4) gvp11= +----------- + +:Syntax: gvp11=<addr-mask> + +The earlier versions of the GVP driver did not handle DMA +address-mask settings correctly which made it necessary for some +people to use this option, in order to get their GVP controller +running under Linux. These problems have hopefully been solved and the +use of this option is now highly unrecommended! + +Incorrect use can lead to unpredictable behavior, so please only use +this option if you *know* what you are doing and have a reason to do +so. In any case if you experience problems and need to use this +option, please inform us about it by mailing to the Linux/68k kernel +mailing list. + +The address mask set by this option specifies which addresses are +valid for DMA with the GVP Series II SCSI controller. An address is +valid, if no bits are set except the bits that are set in the mask, +too. + +Some versions of the GVP can only DMA into a 24 bit address range, +some can address a 25 bit address range while others can use the whole +32 bit address range for DMA. The correct setting depends on your +controller and should be autodetected by the driver. An example is the +24 bit region which is specified by a mask of 0x00fffffe. |