plan.ini(8): document new kernel options

sys/man/8/plan9.ini

@@ -55,7 +55,7 @@ are used by the kernel and are not converted into environment variables.
 .PP
 The following sections describe how variables are used.
 .SS ETHERNET
-.SS \fLetherX=value\fP
+.SS \fLether\fIX\fL=\fIvalue\fP
 This defines an Ethernet interface.
 .IR X ,
 a unique monotonically increasing number beginning at 0,
@@ -384,8 +384,10 @@ Intersil Prism 2.5 chipset.
 .SS DISKS, TAPES
 (S)ATA controllers are autodetected.
 .SS \fL*nodma=\fP
-disable DMA on ata devices.
-.SS \fLscsiX=value\fP
+disables dma on ata devices.
+.SS \fL*sd\fIXX\fLdma=on\fP
+explicitly enables dma on a specific ata device.
+.SS \fLscsi\fIX\fL=value\fP
 This defines a SCSI interface which cannot be automatically detected
 by the kernel.
 .PP
@@ -432,7 +434,7 @@ and
 .I slot
 to use as a root device for bootstrapping.
 .SS AUDIO
-.SS \fLaudioX=value\fP
+.SS \fLaudio\fIX\fL=\fIvalue\fP
 This defines a sound interface.
 .PP
 Known types are
@@ -481,7 +483,7 @@ and need no configuration lines.
 The line
 .B serial=type=com
 can be used to specify settings for a PCMCIA modem.
-.SS \fLmouseport=value\fP
+.SS \fLmouseport=\fIvalue\fP
 This specifies where the mouse is attached.
 .I Value
 can be
@@ -498,16 +500,17 @@ for COM1
 .TP
 .B 1
 for COM2
-.SS \fLmodemport=value\fP
+.SS \fLmodemport=\fIvalue\fP
 Picks the UART line to call out on.
 This is used when connecting to a file server over
 an async line.
 .I Value
 is the number of the port.
-.SS \fLconsole=value params\fP
+.SS \fLconsole=\fIvalue params\fP
 This is used to specify the console device.
 The default
-value is
+.I value
+is
 .BR cga ;
 a number
 .B 0
@@ -547,7 +550,7 @@ with odd parity.
 .SS "PC CARD"
 .SS \fLpccard0=disabled\fP
 Disable probing for and automatic configuration of PC card controllers.
-.SS \fLpcmciaX=type=XXX irq=value\fP
+.SS \fLpcmcia\fIX\fL=type=XXX irq=\fIvalue\fP
 If the default IRQ for the
 PCMCIA
 is correct, this entry can be omitted.  The value of
@@ -556,34 +559,37 @@ is ignored.
 .SS \fLpcmcia0=disabled\fP
 Disable probing for and automatic configuration of PCMCIA controllers.
 .SS BOOTING
-.SS \fLbootfile=value\fP
+.SS \fLbootfile=\fIvalue\fP
 This is used to direct the actions of
 .IR 9boot (8)
 by naming the file from which to load the kernel in
 the current BIOS boot device.
-.SS \fLbootargs=value\fP
-The value of this variable is passed to
+.SS \fLbootargs=\fIvalue\fP
+The
+.I value
+of this variable is passed to
 .IR boot (8)
-by the kernel as the name of the root file system.
+by the kernel as the name of the root file system to
+automatically mount and boot into.
 It is typically used to specify additional arguments to
 pass to
-.IR kfs (4)
+.IR cwfs (4)
 or
 .IR ipconfig (8).
 For example, if the system is to run from a local
-.IR kfs (4)
+.IR cwfs (4)
 partition, the definition might read
-.BR bootargs=local!#S/sdC0/fs .
+.BR bootargs=local!/dev/sdC0/fscache .
 See
 .IR boot (8)
 for more.
-.SS \fLnobootprompt=value\fP
+.SS \fLnobootprompt=\fIvalue\fP
 Suppress the
 .L "root from"
 prompt and use
 .I value
 as the answer instead.
-.SS \fLuser=value\fP
+.SS \fLuser=\fIvalue\fP
 Suppress the
 .L "user"
 prompt and use
@@ -597,7 +603,7 @@ to start
 with the
 .B -p
 option, so that it can be debugged.
-.SS \fLfactotumopts=options\fP
+.SS \fLfactotumopts=\fIoptions\fP
 Causes
 .IR boot (8)
 to start
@@ -605,15 +611,7 @@ to start
 with the given
 .IR options ,
 which must be a single word (i.e., contain no whitespace).
-.SS \fLventi=value\fP
-When booting from a local server backed by a local
-or remote venti server,
-this variable specifies how to establish the connection to the
-venti server.
-See
-.IR boot (8)
-for more.
-.SS \fLcfs=value\fP
+.SS \fLcfs=\fIvalue\fP
 This gives the name of the file holding the disk partition
 for the cache file system,
 .IR cfs (4).
@@ -621,19 +619,29 @@ Extending the
 .B bootargs
 example, one would write
 .BR cfs=#S/sdC0/cache .
-.SS \fLbootdisk=value\fP
+.SS \fLbootdisk=\fIvalue\fP
 This deprecated variable was used to specify the disk used by
 the cache file system and other disk-resident services.
 It is superseded by
 .B bootargs
 and
 .BR cfs .
-.SS \fLfs=a.b.c.d\fP
-.SS \fLauth=a.b.c.d\fP
+.SS \fLfs=\fIa.b.c.d\fP
+.SS \fLauth=\fIa.b.c.d\fP
 These specify the IP address of the file and authentication server
 to use when mounting a network-provided root file system.
 They are used only if the addresses cannot be determined via DHCP.
 .SS PROCESSOR
+.SS \fLe820=\fIstart end ...\fP
+This variable is automatically generated by the boot loader (see
+.IR 9boot (8))
+by doing a BIOS E820 memory scan while still in realmode and
+passed to the kernel. The format is a unordered list of 
+hexadecimal 64-bit
+.I start
+and
+.I end
+addresses of the usable memory areas.
 .SS \fL*norealmode=\fP
 The PC kernel switches the processor to 16-bit real mode
 to run BIOS interrupts, for example to find the memory map or to enable VESA.
@@ -641,7 +649,7 @@ This variable disables such switches.
 .SS \fL*noe820scan=\fP
 When available, the PC kernel uses the BIOS E820 memory map
 to size memory.  This variable disables the scan.
-.SS \fL*maxmem=value\fP
+.SS \fL*maxmem=\fIvalue\fP
 This defines the maximum physical address that the system will scan when sizing memory.
 By default the PC operating system will scan up to 3.75 gigabytes
 (0xF0000000, the base of kernel virtual address space), but setting
@@ -650,7 +658,7 @@ will limit the scan.
 .B *maxmem
 must be less than 3.75 gigabytes.
 This variable is not consulted if using the E820 memory map.
-.SS \fL*kernelpercent=value\fP
+.SS \fL*kernelpercent=\fIvalue\fP
 This defines what percentage of available memory is reserved for the kernel allocation pool.
 The remainder is left for user processes.  The default
 .I value
@@ -666,7 +674,7 @@ Terminals use more kernel memory because
 .IR draw (3)
 maintains its graphic images in kernel memory.
 This deprecated option is rarely necessary in newer kernels.
-.SS \fL*nomce=value\fP
+.SS \fL*nomce=\fIvalue\fP
 If machine check exceptions are supported by the processor,
 then they are enabled by default.
 Setting this variable to
@@ -678,12 +686,18 @@ Setting
 .B *nomp
 restricts the kernel to starting only one processor and using the
 traditional interrupt controller.
-.SS \fL*ncpu=value\fP
+.SS \fL*ncpu=\fIvalue\fP
 Setting
 .B *ncpu
 restricts the kernel to starting at most
 .I value
 processors.
+.SS \fL*msi=\fP
+Enables message signaled interrupts on devices that support it (see
+.IR icanhasmsi (8)).
+It is mutually exclusive with the
+.B *nomp=
+option.
 .SS \fL*pcimaxbno=value\fP
 This puts a limit on the maximum bus number probed
 on a PCI bus (default 7).
@@ -693,7 +707,7 @@ of 1 should suffice on a 'standard' motherboard with an AGP slot.
 This, and
 .B *pcimaxdno
 below are rarely used and only on troublesome or suspect hardware.
-.SS \fL*pcimaxdno=value\fP
+.SS \fL*pcimaxdno=\fIvalue\fP
 This puts a limit on the maximum device number probed
 on a PCI bus (default 31).
 .SS \fL*nopcirouting=\fP
@@ -705,14 +719,14 @@ Useful if there is only a limited cga screen available,
 otherwise the textual information about the panic may scroll off.
 .\" .SS \fL*nobios=\fP
 .\" what does this do?  something with pci
-.SS \fLioexclude=value\fP
+.SS \fLioexclude=\fIvalue\fP
 Specifies a list of ranges of I/O ports to exclude from use by drivers.
 Ranges are inclusive on both ends and separated by commas.
 For example:
 .EX
     ioexclude=0x330-0x337,0x430-0x43F
 .EE
-.SS \fLumbexclude=value\fP
+.SS \fLumbexclude=\fIvalue\fP
 Specifies a list of ranges of UMB to exclude from use by drivers.
 Ranges are inclusive on both ends and separated by commas.
 For example:
@@ -730,15 +744,20 @@ battery life (see
 .IR stats (8)).
 It is not on by default because it causes problems on some laptops.
 .SS VIDEO
-.SS \fLmonitor=value\fP
-.SS \fLvgasize=value\fP
+.SS \fLmonitor=\fIvalue\fP
+.SS \fLvgasize=\fIvalue\fP
 These are used not by the kernel but by
 .I termrc
 (see
 .IR cpurc (8))
 when starting
 .IR vga (8).
-.SS \fL*dpms=value\fP
+If
+.I value
+is set to
+.B ask
+then the user is prompted for a choice on boot.
+.SS \fL*dpms=\fIvalue\fP
 This is used to specify the screen blanking behavior of the MGA4xx
 video driver.
 Values are
@@ -748,10 +767,14 @@ and
 .BR off .
 The first two specify differing levels of power saving;
 the third turns the monitor off completely.
+.SS \fL*vesashadow=\fP
+This enables the shadow framebuffer or softscreen of the VESA
+video driver. This is usefull on devices where access to
+the physical framebuffer is slow.
 .SS NVRAM
-.SS \fLnvram=file\fP
-.SS \fLnvrlen=length\fP
-.SS \fLnvroff=offset\fP
+.SS \fLnvram=\fIfile\fP
+.SS \fLnvrlen=\fIlength\fP
+.SS \fLnvroff=\fIoffset\fP
 This is used to specify an nvram device and optionally the length of the ram
 and read/write offset to use.
 These values are consulted by
@@ -762,7 +785,7 @@ The most common use of the nvram is to hold a
 .IR secstore (1)
 password for use by
 .IR factotum (4).
-.SS \fLnvr=value\fP
+.SS \fLnvr=\fIvalue\fP
 This is used by the WORM file server kernel to locate a file holding information
 to configure the file system.
 The file cannot live on a SCSI disk.