1 2 3 Command Line Options for Linux/m68k 4 =================================== 5 6Last Update: 2 May 1999 7Linux/m68k version: 2.2.6 8Author: Roman.Hodek@informatik.uni-erlangen.de (Roman Hodek) 9Update: jds@kom.auc.dk (Jes Sorensen) and faq@linux-m68k.org (Chris Lawrence) 10 110) Introduction 12=============== 13 14 Often I've been asked which command line options the Linux/m68k 15kernel understands, or how the exact syntax for the ... option is, or 16... about the option ... . I hope, this document supplies all the 17answers... 18 19 Note that some options might be outdated, their descriptions being 20incomplete or missing. Please update the information and send in the 21patches. 22 23 241) Overview of the Kernel's Option Processing 25============================================= 26 27The kernel knows three kinds of options on its command line: 28 29 1) kernel options 30 2) environment settings 31 3) arguments for init 32 33To which of these classes an argument belongs is determined as 34follows: 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 36is known to the kernel, it belongs to class 1. Otherwise, if the 37argument contains an '=', it is of class 2, and the definition is put 38into init's environment. All other arguments are passed to init as 39command line options. 40 41 This document describes the valid kernel options for Linux/m68k in 42the version mentioned at the start of this file. Later revisions may 43add new such options, and some may be missing in older versions. 44 45 In general, the value (the part after the '=') of an option is a 46list of values separated by commas. The interpretation of these values 47is up to the driver that "owns" the option. This association of 48options with drivers is also the reason that some are further 49subdivided. 50 51 522) General Kernel Options 53========================= 54 552.1) root= 56---------- 57 58Syntax: root=/dev/<device> 59 or: root=<hex_number> 60 61This tells the kernel which device it should mount as the root 62filesystem. The device must be a block device with a valid filesystem 63on it. 64 65 The first syntax gives the device by name. These names are converted 66into a major/minor number internally in the kernel in an unusual way. 67Normally, this "conversion" is done by the device files in /dev, but 68this isn't possible here, because the root filesystem (with /dev) 69isn't mounted yet... So the kernel parses the name itself, with some 70hardcoded name to number mappings. The name must always be a 71combination of two or three letters, followed by a decimal number. 72Valid names are: 73 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) 85 /dev/ada: -> 0x1c00 (first ACSI device) 86 /dev/adb: -> 0x1c10 (second ACSI device) 87 /dev/adc: -> 0x1c20 (third ACSI device) 88 /dev/add: -> 0x1c30 (forth ACSI device) 89 90The last four names are available only if the kernel has been compiled 91with Atari and ACSI support. 92 93 The name must be followed by a decimal number, that stands for the 94partition number. Internally, the value of the number is just 95added to the device number mentioned in the table above. The 96exceptions are /dev/ram and /dev/fd, where /dev/ram refers to an 97initial ramdisk loaded by your bootstrap program (please consult the 98instructions for your bootstrap program to find out how to load an 99initial ramdisk). As of kernel version 2.0.18 you must specify 100/dev/ram as the root device if you want to boot from an initial 101ramdisk. For the floppy devices, /dev/fd, the number stands for the 102floppy drive number (there are no partitions on floppy disks). I.e., 103/dev/fd0 stands for the first drive, /dev/fd1 for the second, and so 104on. Since the number is just added, you can also force the disk format 105by adding a number greater than 3. If you look into your /dev 106directory, use can see the /dev/fd0D720 has major 2 and minor 16. You 107can specify this device for the root FS by writing "root=/dev/fd16" on 108the kernel command line. 109 110[Strange and maybe uninteresting stuff ON] 111 112 This unusual translation of device names has some strange 113consequences: If, for example, you have a symbolic link from /dev/fd 114to /dev/fd0D720 as an abbreviation for floppy driver #0 in DD format, 115you cannot use this name for specifying the root device, because the 116kernel cannot see this symlink before mounting the root FS and it 117isn't in the table above. If you use it, the root device will not be 118set at all, without an error message. Another example: You cannot use a 119partition on e.g. the sixth SCSI disk as the root filesystem, if you 120want to specify it by name. This is, because only the devices up to 121/dev/sde are in the table above, but not /dev/sdf. Although, you can 122use the sixth SCSI disk for the root FS, but you have to specify the 123device by number... (see below). Or, even more strange, you can use the 124fact that there is no range checking of the partition number, and your 125knowledge that each disk uses 16 minors, and write "root=/dev/sde17" 126(for /dev/sdf1). 127 128[Strange and maybe uninteresting stuff OFF] 129 130 If the device containing your root partition isn't in the table 131above, you can also specify it by major and minor numbers. These are 132written in hex, with no prefix and no separator between. E.g., if you 133have a CD with contents appropriate as a root filesystem in the first 134SCSI CD-ROM drive, you boot from it by "root=0b00". Here, hex "0b" = 135decimal 11 is the major of SCSI CD-ROMs, and the minor 0 stands for 136the first of these. You can find out all valid major numbers by 137looking into include/linux/major.h. 138 139 1402.2) ro, rw 141----------- 142 143Syntax: ro 144 or: rw 145 146These two options tell the kernel whether it should mount the root 147filesystem read-only or read-write. The default is read-only, except 148for ramdisks, which default to read-write. 149 150 1512.3) debug 152---------- 153 154Syntax: debug 155 156This raises the kernel log level to 10 (the default is 7). This is the 157same level as set by the "dmesg" command, just that the maximum level 158selectable by dmesg is 8. 159 160 1612.4) debug= 162----------- 163 164Syntax: debug=<device> 165 166This option causes certain kernel messages be printed to the selected 167debugging device. This can aid debugging the kernel, since the 168messages can be captured and analyzed on some other machine. Which 169devices are possible depends on the machine type. There are no checks 170for the validity of the device name. If the device isn't implemented, 171nothing happens. 172 173 Messages logged this way are in general stack dumps after kernel 174memory faults or bad kernel traps, and kernel panics. To be exact: all 175messages of level 0 (panic messages) and all messages printed while 176the log level is 8 or more (their level doesn't matter). Before stack 177dumps, the kernel sets the log level to 10 automatically. A level of 178at least 8 can also be set by the "debug" command line option (see 1792.3) and at run time with "dmesg -n 8". 180 181Devices possible for Amiga: 182 183 - "ser": built-in serial port; parameters: 9600bps, 8N1 184 - "mem": Save the messages to a reserved area in chip mem. After 185 rebooting, they can be read under AmigaOS with the tool 186 'dmesg'. 187 188Devices possible for Atari: 189 190 - "ser1": ST-MFP serial port ("Modem1"); parameters: 9600bps, 8N1 191 - "ser2": SCC channel B serial port ("Modem2"); parameters: 9600bps, 8N1 192 - "ser" : default serial port 193 This is "ser2" for a Falcon, and "ser1" for any other machine 194 - "midi": The MIDI port; parameters: 31250bps, 8N1 195 - "par" : parallel port 196 The printing routine for this implements a timeout for the 197 case there's no printer connected (else the kernel would 198 lock up). The timeout is not exact, but usually a few 199 seconds. 200 201 2022.6) ramdisk= 203------------- 204 205Syntax: ramdisk=<size> 206 207 This option instructs the kernel to set up a ramdisk of the given 208size in KBytes. Do not use this option if the ramdisk contents are 209passed by bootstrap! In this case, the size is selected automatically 210and should not be overwritten. 211 212 The only application is for root filesystems on floppy disks, that 213should be loaded into memory. To do that, select the corresponding 214size of the disk as ramdisk size, and set the root device to the disk 215drive (with "root="). 216 217 2182.7) swap= 2192.8) buff= 220----------- 221 222 I can't find any sign of these options in 2.2.6. 223 224 2253) General Device Options (Amiga and Atari) 226=========================================== 227 2283.1) ether= 229----------- 230 231Syntax: ether=[<irq>[,<base_addr>[,<mem_start>[,<mem_end>]]]],<dev-name> 232 233 <dev-name> is the name of a net driver, as specified in 234drivers/net/Space.c in the Linux source. Most prominent are eth0, ... 235eth3, sl0, ... sl3, ppp0, ..., ppp3, dummy, and lo. 236 237 The non-ethernet drivers (sl, ppp, dummy, lo) obviously ignore the 238settings by this options. Also, the existing ethernet drivers for 239Linux/m68k (ariadne, a2065, hydra) don't use them because Zorro boards 240are really Plug-'n-Play, so the "ether=" option is useless altogether 241for Linux/m68k. 242 243 2443.2) hd= 245-------- 246 247Syntax: hd=<cylinders>,<heads>,<sectors> 248 249 This option sets the disk geometry of an IDE disk. The first hd= 250option is for the first IDE disk, the second for the second one. 251(I.e., you can give this option twice.) In most cases, you won't have 252to use this option, since the kernel can obtain the geometry data 253itself. It exists just for the case that this fails for one of your 254disks. 255 256 2573.3) max_scsi_luns= 258------------------- 259 260Syntax: max_scsi_luns=<n> 261 262 Sets the maximum number of LUNs (logical units) of SCSI devices to 263be scanned. Valid values for <n> are between 1 and 8. Default is 8 if 264"Probe all LUNs on each SCSI device" was selected during the kernel 265configuration, else 1. 266 267 2683.4) st= 269-------- 270 271Syntax: st=<buffer_size>,[<write_thres>,[<max_buffers>]] 272 273 Sets several parameters of the SCSI tape driver. <buffer_size> is 274the number of 512-byte buffers reserved for tape operations for each 275device. <write_thres> sets the number of blocks which must be filled 276to start an actual write operation to the tape. Maximum value is the 277total number of buffers. <max_buffer> limits the total number of 278buffers allocated for all tape devices. 279 280 2813.5) dmasound= 282-------------- 283 284Syntax: dmasound=[<buffers>,<buffer-size>[,<catch-radius>]] 285 286 This option controls some configurations of the Linux/m68k DMA sound 287driver (Amiga and Atari): <buffers> is the number of buffers you want 288to use (minimum 4, default 4), <buffer-size> is the size of each 289buffer in kilobytes (minimum 4, default 32) and <catch-radius> says 290how much percent of error will be tolerated when setting a frequency 291(maximum 10, default 0). For example with 3% you can play 8000Hz 292AU-Files on the Falcon with its hardware frequency of 8195Hz and thus 293don't need to expand the sound. 294 295 296 2974) Options for Atari Only 298========================= 299 3004.1) video= 301----------- 302 303Syntax: video=<fbname>:<sub-options...> 304 305The <fbname> parameter specifies the name of the frame buffer, 306eg. most atari users will want to specify `atafb' here. The 307<sub-options> is a comma-separated list of the sub-options listed 308below. 309 310NB: Please notice that this option was renamed from `atavideo' to 311 `video' during the development of the 1.3.x kernels, thus you 312 might need to update your boot-scripts if upgrading to 2.x from 313 an 1.2.x kernel. 314 315NBB: The behavior of video= was changed in 2.1.57 so the recommended 316option is to specify the name of the frame buffer. 317 3184.1.1) Video Mode 319----------------- 320 321This sub-option may be any of the predefined video modes, as listed 322in atari/atafb.c in the Linux/m68k source tree. The kernel will 323activate the given video mode at boot time and make it the default 324mode, if the hardware allows. Currently defined names are: 325 326 - stlow : 320x200x4 327 - stmid, default5 : 640x200x2 328 - sthigh, default4: 640x400x1 329 - ttlow : 320x480x8, TT only 330 - ttmid, default1 : 640x480x4, TT only 331 - tthigh, default2: 1280x960x1, TT only 332 - vga2 : 640x480x1, Falcon only 333 - vga4 : 640x480x2, Falcon only 334 - vga16, default3 : 640x480x4, Falcon only 335 - vga256 : 640x480x8, Falcon only 336 - falh2 : 896x608x1, Falcon only 337 - falh16 : 896x608x4, Falcon only 338 339 If no video mode is given on the command line, the kernel tries the 340modes names "default<n>" in turn, until one is possible with the 341hardware in use. 342 343 A video mode setting doesn't make sense, if the external driver is 344activated by a "external:" sub-option. 345 3464.1.2) inverse 347-------------- 348 349Invert the display. This affects both, text (consoles) and graphics 350(X) display. Usually, the background is chosen to be black. With this 351option, you can make the background white. 352 3534.1.3) font 354----------- 355 356Syntax: font:<fontname> 357 358Specify the font to use in text modes. Currently you can choose only 359between `VGA8x8', `VGA8x16' and `PEARL8x8'. `VGA8x8' is default, if the 360vertical size of the display is less than 400 pixel rows. Otherwise, the 361`VGA8x16' font is the default. 362 3634.1.4) hwscroll_ 364---------------- 365 366Syntax: hwscroll_<n> 367 368The number of additional lines of video memory to reserve for 369speeding up the scrolling ("hardware scrolling"). Hardware scrolling 370is possible only if the kernel can set the video base address in steps 371fine enough. This is true for STE, MegaSTE, TT, and Falcon. It is not 372possible with plain STs and graphics cards (The former because the 373base address must be on a 256 byte boundary there, the latter because 374the kernel doesn't know how to set the base address at all.) 375 376 By default, <n> is set to the number of visible text lines on the 377display. Thus, the amount of video memory is doubled, compared to no 378hardware scrolling. You can turn off the hardware scrolling altogether 379by setting <n> to 0. 380 3814.1.5) internal: 382---------------- 383 384Syntax: internal:<xres>;<yres>[;<xres_max>;<yres_max>;<offset>] 385 386This option specifies the capabilities of some extended internal video 387hardware, like e.g. OverScan. <xres> and <yres> give the (extended) 388dimensions of the screen. 389 390 If your OverScan needs a black border, you have to write the last 391three arguments of the "internal:". <xres_max> is the maximum line 392length the hardware allows, <yres_max> the maximum number of lines. 393<offset> is the offset of the visible part of the screen memory to its 394physical start, in bytes. 395 396 Often, extended interval video hardware has to be activated somehow. 397For this, see the "sw_*" options below. 398 3994.1.6) external: 400---------------- 401 402Syntax: 403 external:<xres>;<yres>;<depth>;<org>;<scrmem>[;<scrlen>[;<vgabase>\ 404 [;<colw>[;<coltype>[;<xres_virtual>]]]]] 405 406[I had to break this line...] 407 408 This is probably the most complicated parameter... It specifies that 409you have some external video hardware (a graphics board), and how to 410use it under Linux/m68k. The kernel cannot know more about the hardware 411than you tell it here! The kernel also is unable to set or change any 412video modes, since it doesn't know about any board internal. So, you 413have to switch to that video mode before you start Linux, and cannot 414switch to another mode once Linux has started. 415 416 The first 3 parameters of this sub-option should be obvious: <xres>, 417<yres> and <depth> give the dimensions of the screen and the number of 418planes (depth). The depth is is the logarithm to base 2 of the number 419of colors possible. (Or, the other way round: The number of colors is 4202^depth). 421 422 You have to tell the kernel furthermore how the video memory is 423organized. This is done by a letter as <org> parameter: 424 425 'n': "normal planes", i.e. one whole plane after another 426 'i': "interleaved planes", i.e. 16 bit of the first plane, than 16 bit 427 of the next, and so on... This mode is used only with the 428 built-in Atari video modes, I think there is no card that 429 supports this mode. 430 'p': "packed pixels", i.e. <depth> consecutive bits stand for all 431 planes of one pixel; this is the most common mode for 8 planes 432 (256 colors) on graphic cards 433 't': "true color" (more or less packed pixels, but without a color 434 lookup table); usually depth is 24 435 436For monochrome modes (i.e., <depth> is 1), the <org> letter has a 437different meaning: 438 439 'n': normal colors, i.e. 0=white, 1=black 440 'i': inverted colors, i.e. 0=black, 1=white 441 442 The next important information about the video hardware is the base 443address of the video memory. That is given in the <scrmem> parameter, 444as a hexadecimal number with a "0x" prefix. You have to find out this 445address in the documentation of your hardware. 446 447 The next parameter, <scrlen>, tells the kernel about the size of the 448video memory. If it's missing, the size is calculated from <xres>, 449<yres>, and <depth>. For now, it is not useful to write a value here. 450It would be used only for hardware scrolling (which isn't possible 451with the external driver, because the kernel cannot set the video base 452address), or for virtual resolutions under X (which the X server 453doesn't support yet). So, it's currently best to leave this field 454empty, either by ending the "external:" after the video address or by 455writing two consecutive semicolons, if you want to give a <vgabase> 456(it is allowed to leave this parameter empty). 457 458 The <vgabase> parameter is optional. If it is not given, the kernel 459cannot read or write any color registers of the video hardware, and 460thus you have to set appropriate colors before you start Linux. But if 461your card is somehow VGA compatible, you can tell the kernel the base 462address of the VGA register set, so it can change the color lookup 463table. You have to look up this address in your board's documentation. 464To avoid misunderstandings: <vgabase> is the _base_ address, i.e. a 4k 465aligned address. For read/writing the color registers, the kernel 466uses the addresses vgabase+0x3c7...vgabase+0x3c9. The <vgabase> 467parameter is written in hexadecimal with a "0x" prefix, just as 468<scrmem>. 469 470 <colw> is meaningful only if <vgabase> is specified. It tells the 471kernel how wide each of the color register is, i.e. the number of bits 472per single color (red/green/blue). Default is 6, another quite usual 473value is 8. 474 475 Also <coltype> is used together with <vgabase>. It tells the kernel 476about the color register model of your gfx board. Currently, the types 477"vga" (which is also the default) and "mv300" (SANG MV300) are 478implemented. 479 480 Parameter <xres_virtual> is required for ProMST or ET4000 cards where 481the physical linelength differs from the visible length. With ProMST, 482xres_virtual must be set to 2048. For ET4000, xres_virtual depends on the 483initialisation of the video-card. 484If you're missing a corresponding yres_virtual: the external part is legacy, 485therefore we don't support hardware-dependent functions like hardware-scroll, 486panning or blanking. 487 4884.1.7) eclock: 489-------------- 490 491The external pixel clock attached to the Falcon VIDEL shifter. This 492currently works only with the ScreenWonder! 493 4944.1.8) monitorcap: 495------------------- 496 497Syntax: monitorcap:<vmin>;<vmax>;<hmin>;<hmax> 498 499This describes the capabilities of a multisync monitor. Don't use it 500with a fixed-frequency monitor! For now, only the Falcon frame buffer 501uses the settings of "monitorcap:". 502 503 <vmin> and <vmax> are the minimum and maximum, resp., vertical frequencies 504your monitor can work with, in Hz. <hmin> and <hmax> are the same for 505the horizontal frequency, in kHz. 506 507 The defaults are 58;62;31;32 (VGA compatible). 508 509 The defaults for TV/SC1224/SC1435 cover both PAL and NTSC standards. 510 5114.1.9) keep 512------------ 513 514If this option is given, the framebuffer device doesn't do any video 515mode calculations and settings on its own. The only Atari fb device 516that does this currently is the Falcon. 517 518 What you reach with this: Settings for unknown video extensions 519aren't overridden by the driver, so you can still use the mode found 520when booting, when the driver doesn't know to set this mode itself. 521But this also means, that you can't switch video modes anymore... 522 523 An example where you may want to use "keep" is the ScreenBlaster for 524the Falcon. 525 526 5274.2) atamouse= 528-------------- 529 530Syntax: atamouse=<x-threshold>,[<y-threshold>] 531 532 With this option, you can set the mouse movement reporting threshold. 533This is the number of pixels of mouse movement that have to accumulate 534before the IKBD sends a new mouse packet to the kernel. Higher values 535reduce the mouse interrupt load and thus reduce the chance of keyboard 536overruns. Lower values give a slightly faster mouse responses and 537slightly better mouse tracking. 538 539 You can set the threshold in x and y separately, but usually this is 540of little practical use. If there's just one number in the option, it 541is used for both dimensions. The default value is 2 for both 542thresholds. 543 544 5454.3) ataflop= 546------------- 547 548Syntax: ataflop=<drive type>[,<trackbuffering>[,<steprateA>[,<steprateB>]]] 549 550 The drive type may be 0, 1, or 2, for DD, HD, and ED, resp. This 551 setting affects how many buffers are reserved and which formats are 552 probed (see also below). The default is 1 (HD). Only one drive type 553 can be selected. If you have two disk drives, select the "better" 554 type. 555 556 The second parameter <trackbuffer> tells the kernel whether to use 557 track buffering (1) or not (0). The default is machine-dependent: 558 no for the Medusa and yes for all others. 559 560 With the two following parameters, you can change the default 561 steprate used for drive A and B, resp. 562 563 5644.4) atascsi= 565------------- 566 567Syntax: atascsi=<can_queue>[,<cmd_per_lun>[,<scat-gat>[,<host-id>[,<tagged>]]]] 568 569 This option sets some parameters for the Atari native SCSI driver. 570Generally, any number of arguments can be omitted from the end. And 571for each of the numbers, a negative value means "use default". The 572defaults depend on whether TT-style or Falcon-style SCSI is used. 573Below, defaults are noted as n/m, where the first value refers to 574TT-SCSI and the latter to Falcon-SCSI. If an illegal value is given 575for one parameter, an error message is printed and that one setting is 576ignored (others aren't affected). 577 578 <can_queue>: 579 This is the maximum number of SCSI commands queued internally to the 580 Atari SCSI driver. A value of 1 effectively turns off the driver 581 internal multitasking (if it causes problems). Legal values are >= 582 1. <can_queue> can be as high as you like, but values greater than 583 <cmd_per_lun> times the number of SCSI targets (LUNs) you have 584 don't make sense. Default: 16/8. 585 586 <cmd_per_lun>: 587 Maximum number of SCSI commands issued to the driver for one 588 logical unit (LUN, usually one SCSI target). Legal values start 589 from 1. If tagged queuing (see below) is not used, values greater 590 than 2 don't make sense, but waste memory. Otherwise, the maximum 591 is the number of command tags available to the driver (currently 592 32). Default: 8/1. (Note: Values > 1 seem to cause problems on a 593 Falcon, cause not yet known.) 594 595 The <cmd_per_lun> value at a great part determines the amount of 596 memory SCSI reserves for itself. The formula is rather 597 complicated, but I can give you some hints: 598 no scatter-gather : cmd_per_lun * 232 bytes 599 full scatter-gather: cmd_per_lun * approx. 17 Kbytes 600 601 <scat-gat>: 602 Size of the scatter-gather table, i.e. the number of requests 603 consecutive on the disk that can be merged into one SCSI command. 604 Legal values are between 0 and 255. Default: 255/0. Note: This 605 value is forced to 0 on a Falcon, since scatter-gather isn't 606 possible with the ST-DMA. Not using scatter-gather hurts 607 performance significantly. 608 609 <host-id>: 610 The SCSI ID to be used by the initiator (your Atari). This is 611 usually 7, the highest possible ID. Every ID on the SCSI bus must 612 be unique. Default: determined at run time: If the NV-RAM checksum 613 is valid, and bit 7 in byte 30 of the NV-RAM is set, the lower 3 614 bits of this byte are used as the host ID. (This method is defined 615 by Atari and also used by some TOS HD drivers.) If the above 616 isn't given, the default ID is 7. (both, TT and Falcon). 617 618 <tagged>: 619 0 means turn off tagged queuing support, all other values > 0 mean 620 use tagged queuing for targets that support it. Default: currently 621 off, but this may change when tagged queuing handling has been 622 proved to be reliable. 623 624 Tagged queuing means that more than one command can be issued to 625 one LUN, and the SCSI device itself orders the requests so they 626 can be performed in optimal order. Not all SCSI devices support 627 tagged queuing (:-(). 628 6294.6 switches= 630------------- 631 632Syntax: switches=<list of switches> 633 634 With this option you can switch some hardware lines that are often 635used to enable/disable certain hardware extensions. Examples are 636OverScan, overclocking, ... 637 638 The <list of switches> is a comma-separated list of the following 639items: 640 641 ikbd: set RTS of the keyboard ACIA high 642 midi: set RTS of the MIDI ACIA high 643 snd6: set bit 6 of the PSG port A 644 snd7: set bit 6 of the PSG port A 645 646It doesn't make sense to mention a switch more than once (no 647difference to only once), but you can give as many switches as you 648want to enable different features. The switch lines are set as early 649as possible during kernel initialization (even before determining the 650present hardware.) 651 652 All of the items can also be prefixed with "ov_", i.e. "ov_ikbd", 653"ov_midi", ... These options are meant for switching on an OverScan 654video extension. The difference to the bare option is that the 655switch-on is done after video initialization, and somehow synchronized 656to the HBLANK. A speciality is that ov_ikbd and ov_midi are switched 657off before rebooting, so that OverScan is disabled and TOS boots 658correctly. 659 660 If you give an option both, with and without the "ov_" prefix, the 661earlier initialization ("ov_"-less) takes precedence. But the 662switching-off on reset still happens in this case. 663 6644.5) stram_swap= 665---------------- 666 667Syntax: stram_swap=<do_swap>[,<max_swap>] 668 669 This option is available only if the kernel has been compiled with 670CONFIG_STRAM_SWAP enabled. Normally, the kernel then determines 671dynamically whether to actually use ST-RAM as swap space. (Currently, 672the fraction of ST-RAM must be less or equal 1/3 of total memory to 673enable this swapping.) You can override the kernel's decision by 674specifying this option. 1 for <do_swap> means always enable the swap, 675even if you have less alternate RAM. 0 stands for never swap to 676ST-RAM, even if it's small enough compared to the rest of memory. 677 678 If ST-RAM swapping is enabled, the kernel usually uses all free 679ST-RAM as swap "device". If the kernel resides in ST-RAM, the region 680allocated by it is obviously never used for swapping :-) You can also 681limit this amount by specifying the second parameter, <max_swap>, if 682you want to use parts of ST-RAM as normal system memory. <max_swap> is 683in kBytes and the number should be a multiple of 4 (otherwise: rounded 684down). 685 6865) Options for Amiga Only: 687========================== 688 6895.1) video= 690----------- 691 692Syntax: video=<fbname>:<sub-options...> 693 694The <fbname> parameter specifies the name of the frame buffer, valid 695options are `amifb', `cyber', 'virge', `retz3' and `clgen', provided 696that the respective frame buffer devices have been compiled into the 697kernel (or compiled as loadable modules). The behavior of the <fbname> 698option was changed in 2.1.57 so it is now recommended to specify this 699option. 700 701The <sub-options> is a comma-separated list of the sub-options listed 702below. This option is organized similar to the Atari version of the 703"video"-option (4.1), but knows fewer sub-options. 704 7055.1.1) video mode 706----------------- 707 708Again, similar to the video mode for the Atari (see 4.1.1). Predefined 709modes depend on the used frame buffer device. 710 711OCS, ECS and AGA machines all use the color frame buffer. The following 712predefined video modes are available: 713 714NTSC modes: 715 - ntsc : 640x200, 15 kHz, 60 Hz 716 - ntsc-lace : 640x400, 15 kHz, 60 Hz interlaced 717PAL modes: 718 - pal : 640x256, 15 kHz, 50 Hz 719 - pal-lace : 640x512, 15 kHz, 50 Hz interlaced 720ECS modes: 721 - multiscan : 640x480, 29 kHz, 57 Hz 722 - multiscan-lace : 640x960, 29 kHz, 57 Hz interlaced 723 - euro36 : 640x200, 15 kHz, 72 Hz 724 - euro36-lace : 640x400, 15 kHz, 72 Hz interlaced 725 - euro72 : 640x400, 29 kHz, 68 Hz 726 - euro72-lace : 640x800, 29 kHz, 68 Hz interlaced 727 - super72 : 800x300, 23 kHz, 70 Hz 728 - super72-lace : 800x600, 23 kHz, 70 Hz interlaced 729 - dblntsc-ff : 640x400, 27 kHz, 57 Hz 730 - dblntsc-lace : 640x800, 27 kHz, 57 Hz interlaced 731 - dblpal-ff : 640x512, 27 kHz, 47 Hz 732 - dblpal-lace : 640x1024, 27 kHz, 47 Hz interlaced 733 - dblntsc : 640x200, 27 kHz, 57 Hz doublescan 734 - dblpal : 640x256, 27 kHz, 47 Hz doublescan 735VGA modes: 736 - vga : 640x480, 31 kHz, 60 Hz 737 - vga70 : 640x400, 31 kHz, 70 Hz 738 739Please notice that the ECS and VGA modes require either an ECS or AGA 740chipset, and that these modes are limited to 2-bit color for the ECS 741chipset and 8-bit color for the AGA chipset. 742 7435.1.2) depth 744------------ 745 746Syntax: depth:<nr. of bit-planes> 747 748Specify the number of bit-planes for the selected video-mode. 749 7505.1.3) inverse 751-------------- 752 753Use inverted display (black on white). Functionally the same as the 754"inverse" sub-option for the Atari. 755 7565.1.4) font 757----------- 758 759Syntax: font:<fontname> 760 761Specify the font to use in text modes. Functionally the same as the 762"font" sub-option for the Atari, except that `PEARL8x8' is used instead 763of `VGA8x8' if the vertical size of the display is less than 400 pixel 764rows. 765 7665.1.5) monitorcap: 767------------------- 768 769Syntax: monitorcap:<vmin>;<vmax>;<hmin>;<hmax> 770 771This describes the capabilities of a multisync monitor. For now, only 772the color frame buffer uses the settings of "monitorcap:". 773 774 <vmin> and <vmax> are the minimum and maximum, resp., vertical frequencies 775your monitor can work with, in Hz. <hmin> and <hmax> are the same for 776the horizontal frequency, in kHz. 777 778 The defaults are 50;90;15;38 (Generic Amiga multisync monitor). 779 780 7815.2) fd_def_df0= 782---------------- 783 784Syntax: fd_def_df0=<value> 785 786Sets the df0 value for "silent" floppy drives. The value should be in 787hexadecimal with "0x" prefix. 788 789 7905.3) wd33c93= 791------------- 792 793Syntax: wd33c93=<sub-options...> 794 795These options affect the A590/A2091, A3000 and GVP Series II SCSI 796controllers. 797 798The <sub-options> is a comma-separated list of the sub-options listed 799below. 800 8015.3.1) nosync 802------------- 803 804Syntax: nosync:bitmask 805 806 bitmask is a byte where the 1st 7 bits correspond with the 7 807possible SCSI devices. Set a bit to prevent sync negotiation on that 808device. To maintain backwards compatibility, a command-line such as 809"wd33c93=255" will be automatically translated to 810"wd33c93=nosync:0xff". The default is to disable sync negotiation for 811all devices, eg. nosync:0xff. 812 8135.3.2) period 814------------- 815 816Syntax: period:ns 817 818 `ns' is the minimum # of nanoseconds in a SCSI data transfer 819period. Default is 500; acceptable values are 250 - 1000. 820 8215.3.3) disconnect 822----------------- 823 824Syntax: disconnect:x 825 826 Specify x = 0 to never allow disconnects, 2 to always allow them. 827x = 1 does 'adaptive' disconnects, which is the default and generally 828the best choice. 829 8305.3.4) debug 831------------ 832 833Syntax: debug:x 834 835 If `DEBUGGING_ON' is defined, x is a bit mask that causes various 836types of debug output to printed - see the DB_xxx defines in 837wd33c93.h. 838 8395.3.5) clock 840------------ 841 842Syntax: clock:x 843 844 x = clock input in MHz for WD33c93 chip. Normal values would be from 8458 through 20. The default value depends on your hostadapter(s), 846default for the A3000 internal controller is 14, for the A2091 it's 8 847and for the GVP hostadapters it's either 8 or 14, depending on the 848hostadapter and the SCSI-clock jumper present on some GVP 849hostadapters. 850 8515.3.6) next 852----------- 853 854 No argument. Used to separate blocks of keywords when there's more 855than one wd33c93-based host adapter in the system. 856 8575.3.7) nodma 858------------ 859 860Syntax: nodma:x 861 862 If x is 1 (or if the option is just written as "nodma"), the WD33c93 863controller will not use DMA (= direct memory access) to access the 864Amiga's memory. This is useful for some systems (like A3000's and 865A4000's with the A3640 accelerator, revision 3.0) that have problems 866using DMA to chip memory. The default is 0, i.e. to use DMA if 867possible. 868 869 8705.4) gvp11= 871----------- 872 873Syntax: gvp11=<addr-mask> 874 875 The earlier versions of the GVP driver did not handle DMA 876address-mask settings correctly which made it necessary for some 877people to use this option, in order to get their GVP controller 878running under Linux. These problems have hopefully been solved and the 879use of this option is now highly unrecommended! 880 881 Incorrect use can lead to unpredictable behavior, so please only use 882this option if you *know* what you are doing and have a reason to do 883so. In any case if you experience problems and need to use this 884option, please inform us about it by mailing to the Linux/68k kernel 885mailing list. 886 887 The address mask set by this option specifies which addresses are 888valid for DMA with the GVP Series II SCSI controller. An address is 889valid, if no bits are set except the bits that are set in the mask, 890too. 891 892 Some versions of the GVP can only DMA into a 24 bit address range, 893some can address a 25 bit address range while others can use the whole 89432 bit address range for DMA. The correct setting depends on your 895controller and should be autodetected by the driver. An example is the 89624 bit region which is specified by a mask of 0x00fffffe. 897 898 8995.5) 53c7xx= 900------------ 901 902Syntax: 53c7xx=<sub-options...> 903 904These options affect the A4000T, A4091, WarpEngine, Blizzard 603e+, 905and GForce 040/060 SCSI controllers on the Amiga, as well as the 906builtin MVME 16x SCSI controller. 907 908The <sub-options> is a comma-separated list of the sub-options listed 909below. 910 9115.5.1) nosync 912------------- 913 914Syntax: nosync:0 915 916 Disables sync negotiation for all devices. Any value after the 917 colon is acceptable (and has the same effect). 918 9195.5.2) noasync 920-------------- 921 922Syntax: noasync:0 923 924 Disables async and sync negotiation for all devices. Any value 925 after the colon is acceptable (and has the same effect). 926 9275.5.3) nodisconnect 928------------------- 929 930Syntax: nodisconnect:0 931 932 Disables SCSI disconnects. Any value after the colon is acceptable 933 (and has the same effect). 934 9355.5.4) validids 936--------------- 937 938Syntax: validids:0xNN 939 940 Specify which SCSI ids the driver should pay attention to. This is 941 a bitmask (i.e. to only pay attention to ID#4, you'd use 0x10). 942 Default is 0x7f (devices 0-6). 943 9445.5.5) opthi 9455.5.6) optlo 946------------ 947 948Syntax: opthi:M,optlo:N 949 950 Specify options for "hostdata->options". The acceptable definitions 951 are listed in drivers/scsi/53c7xx.h; the 32 high bits should be in 952 opthi and the 32 low bits in optlo. They must be specified in the 953 order opthi=M,optlo=N. 954 9555.5.7) next 956----------- 957 958 No argument. Used to separate blocks of keywords when there's more 959 than one 53c7xx host adapter in the system. 960 961 962/* Local Variables: */ 963/* mode: text */ 964/* End: */ 965