Mdoc(7) janitor cleanup.
Reviewed and improved by: ru OK'ed by: phk Approved by: re (rwatson)
This commit is contained in:
simon
parent
43cff8ce43
commit
ff15145473
@ -1,4 +1,4 @@
|
||||
.\" Copyright (c) 2003 Poul-Henning Kamp <phk@FreeBSD.org>
|
||||
.\" Copyright (c) 2003 Poul-Henning Kamp <phk@FreeBSD.org>
|
||||
.\" All rights reserved.
|
||||
.\"
|
||||
.\" Redistribution and use in source and binary forms, with or without
|
||||
@ -25,87 +25,134 @@
|
||||
.\" $FreeBSD$
|
||||
.\"
|
||||
.Dd November 23, 2003
|
||||
.Dt CPU_ELAN 4
|
||||
.Dt CPU_ELAN 4 i386
|
||||
.Os
|
||||
.Sh NAME
|
||||
.Nm CPU_ELAN
|
||||
.Nd AMD Elan 520 CPU support
|
||||
.Sh SYNOPSIS
|
||||
.Cd options CPU_ELAN
|
||||
.Cd options CPU_ELAN_PPS
|
||||
.Cd options CPU_ELAN_XTAL
|
||||
.Cd sysctl machdep.elan_gpio_config
|
||||
.Cd sysctl machdep.elan_freq
|
||||
.Cd options CPU_SOEKRIS
|
||||
.Cd "options CPU_ELAN"
|
||||
.Cd "options CPU_ELAN_PPS"
|
||||
.Cd "options CPU_ELAN_XTAL"
|
||||
.Bl -item -compact
|
||||
.It
|
||||
.Va machdep.elan_gpio_config
|
||||
.It
|
||||
.Va machdep.elan_freq
|
||||
.El
|
||||
.Cd "options CPU_SOEKRIS"
|
||||
.Sh DESCRIPTION
|
||||
.Cd options CPU_ELAN
|
||||
Enables support for the AMD Elan 520 CPU.
|
||||
The
|
||||
.Cd "options CPU_ELAN"
|
||||
enables support for the AMD Elan 520 CPU.
|
||||
.Pp
|
||||
A device "/dev/elan-mmcr" exports the MMCR register bank to userland
|
||||
A device
|
||||
.Pa /dev/elan-mmcr
|
||||
exports the MMCR register bank to userland
|
||||
using
|
||||
.Xr mmap 2 .
|
||||
.Pp
|
||||
The "i8254" timer will be adjusted to the slightly unorthodox
|
||||
frequency 1189161Hz (32768 * 45 * 25 / 31) employed by the Elan.
|
||||
The
|
||||
.Tn i8254
|
||||
timer will be adjusted to the slightly unorthodox
|
||||
frequency 1189161 Hz (32768 * 45 * 25 / 31) employed by the Elan.
|
||||
.Pp
|
||||
A timecounter named "ELAN" is implemented using the general purpose timer 2,
|
||||
A timecounter named
|
||||
.Dq Li ELAN
|
||||
is implemented using the general purpose timer 2,
|
||||
but it will not be usable unless HZ is configured at 150 or higher.
|
||||
This timecounter is much better than the "i8254" timecounter and should be
|
||||
This timecounter is much better than the
|
||||
.Dq Li i8254
|
||||
timecounter and should be
|
||||
used at all times.
|
||||
.Pp
|
||||
The
|
||||
.Cd sysctl machdep.elan_gpio_config
|
||||
.Va machdep.elan_gpio_config
|
||||
.Xr sysctl 8
|
||||
variable
|
||||
enables configuration of the GPIO pins of the CPU.
|
||||
The string must be exactly 32 characters long.
|
||||
A '-' means the GPIO is unavailable.
|
||||
A 'l' (lower-case L) configures a
|
||||
A
|
||||
.Ql -
|
||||
means the GPIO is unavailable.
|
||||
A
|
||||
.Ql l
|
||||
(lower-case ell) configures a
|
||||
.Xr led 4
|
||||
device (active low).
|
||||
A 'L' configures a
|
||||
A
|
||||
.Ql L
|
||||
configures a
|
||||
.Xr led 4
|
||||
device (active higH).
|
||||
A '.' means no configuration for this GPIO.
|
||||
device (active high).
|
||||
A
|
||||
.Ql \&.
|
||||
means no configuration for this GPIO.
|
||||
These
|
||||
.Xr led 4
|
||||
devices will be named "/dev/led/gpio%d".
|
||||
For meaning of 'P', 'e' and 'E', see under
|
||||
.Cd options CPU_ELAN_PPS .
|
||||
devices will be named
|
||||
.Pa /dev/led/gpio%d .
|
||||
For meaning of
|
||||
.Ql P ,
|
||||
.Ql e
|
||||
and
|
||||
.Ql E ,
|
||||
see under
|
||||
.Cd "options CPU_ELAN_PPS" .
|
||||
.Pp
|
||||
The
|
||||
.Cd options CPU_ELAN_XTAL
|
||||
and
|
||||
.Cd sysctl machdep.elan_freq
|
||||
.Cd "options CPU_ELAN_XTAL"
|
||||
and the
|
||||
.Va machdep.elan_freq
|
||||
.Xr sysctl 8
|
||||
variable
|
||||
can be used to set the CPU clock crystal frequency in Hz.
|
||||
The default is 33333333 Hz.
|
||||
.Pp
|
||||
The
|
||||
.Cd options CPU_ELAN_PPS
|
||||
.Cd "options CPU_ELAN_PPS"
|
||||
enables precision timestamping using the RFC2783 PPS-API via the
|
||||
"/dev/elan-mmcr" device.
|
||||
The resolution will be approx 125nsec and the precision \(+- 125nsec.
|
||||
(for 125 nsec read "4 / CPU clock crystal frequency")
|
||||
.Pa /dev/elan-mmcr
|
||||
device.
|
||||
The resolution will be approximately 125 nsec
|
||||
and the precision \(+- 125 nsec.
|
||||
(For 125 nsec read
|
||||
.Dq "4 / CPU clock crystal frequency" . )
|
||||
.Pp
|
||||
The input signal must be connected to the TMR1IN pin and
|
||||
a GPIO pin.
|
||||
The GPIO pin must be configured with a 'P' in
|
||||
.Cd sysctl machdep.elan_gpio_config .
|
||||
The GPIO pin must be configured with a
|
||||
.Ql P
|
||||
in
|
||||
.Va machdep.elan_gpio_config .
|
||||
.Pp
|
||||
In addition one GPIO pin can be configured with either 'e' (active low)
|
||||
or 'E' (active high) to become a "echo" output of the input signal.
|
||||
In addition, one GPIO pin can be configured with either
|
||||
.Ql e
|
||||
(active low)
|
||||
or
|
||||
.Ql E
|
||||
(active high) to become a
|
||||
.Dq echo
|
||||
output of the input signal.
|
||||
Please notice that this signal is not suitable for calibration.
|
||||
.Pp
|
||||
If the
|
||||
.Cd options CPU_SOEKRIS
|
||||
option is given, the support will additionally be tailored to the
|
||||
.Cd "options CPU_SOEKRIS"
|
||||
is given, the support will additionally be tailored to the
|
||||
Soekris Engineering 45xx series of embedded computers.
|
||||
The "error" led will be configured (as "/dev/led/error") and the GPIO pins which are not
|
||||
The
|
||||
.Dq error
|
||||
led will be configured (as
|
||||
.Pa /dev/led/error )
|
||||
and the GPIO pins which are not
|
||||
available will be disabled.
|
||||
.Sh SEE ALSO
|
||||
.Xr sysctl 8 ,
|
||||
.Xr led 4 ,
|
||||
.Xr sysctl 8
|
||||
.Sh HISTORY
|
||||
The
|
||||
.Nm
|
||||
code first appeared in
|
||||
.Fx 5.x .
|
||||
.Fx 4.7 .
|
||||
.Sh AUTHORS
|
||||
.An "Poul-Henning Kamp" Aq phk@FreeBSD.org
|
||||
|
||||
Loading…
Reference in New Issue
Block a user