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Diffstat (limited to 'share/man/man4/man4.i386/CPU_ELAN.4')
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diff --git a/share/man/man4/man4.i386/CPU_ELAN.4 b/share/man/man4/man4.i386/CPU_ELAN.4 new file mode 100644 index 000000000000..7fe774170384 --- /dev/null +++ b/share/man/man4/man4.i386/CPU_ELAN.4 @@ -0,0 +1,158 @@ +.\" Copyright (c) 2003 Poul-Henning Kamp <phk@FreeBSD.org> +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd November 23, 2003 +.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" +.Bl -item -compact +.It +.Va machdep.elan_gpio_config +.It +.Va machdep.elan_freq +.El +.Cd "options CPU_SOEKRIS" +.Sh DESCRIPTION +The +.Cd "options CPU_ELAN" +enables support for the AMD Elan 520 CPU. +.Pp +A device +.Pa /dev/elan-mmcr +exports the MMCR register bank to userland +using +.Xr mmap 2 . +.Pp +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 +.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 +.Dq Li i8254 +timecounter and should be +used at all times. +.Pp +The +.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 +.Ql - +means the GPIO is unavailable. +A +.Ql l +(lower-case ell) configures a +.Xr led 4 +device (active low). +A +.Ql L +configures a +.Xr led 4 +device (active high). +A +.Ql \&. +means no configuration for this GPIO. +These +.Xr led 4 +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 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" +enables precision timestamping using the RFC2783 PPS-API via the +.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 +.Ql P +in +.Va machdep.elan_gpio_config . +.Pp +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" +is given, the support will additionally be tailored to the +Soekris Engineering 45xx series of embedded computers. +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 led 4 , +.Xr sysctl 8 +.Sh HISTORY +The +.Nm +code first appeared in +.Fx 4.7 . +.Sh AUTHORS +.An "Poul-Henning Kamp" Aq phk@FreeBSD.org |