forked from Imagelibrary/rtems
Jay Monkman <jmonkman@frasca.com> submitted the eth_comm BSP for a PPC860
based board.
This commit is contained in:
186
c/src/lib/libcpu/powerpc/mpc860/clock/clock.c
Normal file
186
c/src/lib/libcpu/powerpc/mpc860/clock/clock.c
Normal file
@@ -0,0 +1,186 @@
|
||||
/* clock.c
|
||||
*
|
||||
* This routine initializes the PIT on the MPC860.
|
||||
* The tick frequency is specified by the bsp.
|
||||
*
|
||||
* Author: Jay Monkman (jmonkman@frasca.com)
|
||||
* Copyright (C) 1998 by Frasca International, Inc.
|
||||
*
|
||||
* Derived from c/src/lib/libcpu/ppc/ppc403/clock/clock.c:
|
||||
*
|
||||
* Author: Andrew Bray <andy@i-cubed.co.uk>
|
||||
*
|
||||
* COPYRIGHT (c) 1995 by i-cubed ltd.
|
||||
*
|
||||
* To anyone who acknowledges that this file is provided "AS IS"
|
||||
* without any express or implied warranty:
|
||||
* permission to use, copy, modify, and distribute this file
|
||||
* for any purpose is hereby granted without fee, provided that
|
||||
* the above copyright notice and this notice appears in all
|
||||
* copies, and that the name of i-cubed limited not be used in
|
||||
* advertising or publicity pertaining to distribution of the
|
||||
* software without specific, written prior permission.
|
||||
* i-cubed limited makes no representations about the suitability
|
||||
* of this software for any purpose.
|
||||
*
|
||||
* Derived from c/src/lib/libcpu/hppa1_1/clock/clock.c:
|
||||
*
|
||||
* COPYRIGHT (c) 1989-1998.
|
||||
* On-Line Applications Research Corporation (OAR).
|
||||
* Copyright assigned to U.S. Government, 1994.
|
||||
*
|
||||
* The license and distribution terms for this file may be
|
||||
* found in the file LICENSE in this distribution or at
|
||||
* http://www.OARcorp.com/rtems/license.html.
|
||||
*
|
||||
* $Id$
|
||||
*/
|
||||
|
||||
#include <bsp.h>
|
||||
#include <clockdrv.h>
|
||||
#include <rtems/libio.h>
|
||||
|
||||
#include <stdlib.h> /* for atexit() */
|
||||
#include <mpc860.h>
|
||||
|
||||
extern rtems_cpu_table Cpu_table; /* owned by BSP */
|
||||
|
||||
volatile rtems_unsigned32 Clock_driver_ticks;
|
||||
extern volatile m860_t m860;
|
||||
|
||||
void Clock_exit( void );
|
||||
|
||||
/*
|
||||
* These are set by clock driver during its init
|
||||
*/
|
||||
|
||||
rtems_device_major_number rtems_clock_major = ~0;
|
||||
rtems_device_minor_number rtems_clock_minor;
|
||||
|
||||
/*
|
||||
* ISR Handler
|
||||
*/
|
||||
rtems_isr Clock_isr(rtems_vector_number vector)
|
||||
{
|
||||
m860.piscr |= M860_PISCR_PS;
|
||||
Clock_driver_ticks++;
|
||||
rtems_clock_tick();
|
||||
}
|
||||
|
||||
void Install_clock(rtems_isr_entry clock_isr)
|
||||
{
|
||||
rtems_isr_entry previous_isr;
|
||||
rtems_unsigned32 pit_value;
|
||||
|
||||
Clock_driver_ticks = 0;
|
||||
|
||||
pit_value = BSP_Configuration.microseconds_per_tick *
|
||||
Cpu_table.clicks_per_usec;
|
||||
if (pit_value == 0) {
|
||||
pit_value = 0xffff;
|
||||
} else {
|
||||
pit_value--;
|
||||
}
|
||||
|
||||
if (pit_value > 0xffff) { /* pit is only 16 bits long */
|
||||
rtems_fatal_error_occurred(-1);
|
||||
}
|
||||
if (BSP_Configuration.ticks_per_timeslice) {
|
||||
|
||||
/*
|
||||
* initialize the interval here
|
||||
* First tick is set to right amount of time in the future
|
||||
* Future ticks will be incremented over last value set
|
||||
* in order to provide consistent clicks in the face of
|
||||
* interrupt overhead
|
||||
*/
|
||||
|
||||
rtems_interrupt_catch(clock_isr, PPC_IRQ_LVL0, &previous_isr);
|
||||
|
||||
m860.sccr &= ~(1<<24);
|
||||
m860.pitc = pit_value;
|
||||
|
||||
/* set PIT irq level, enable PIT, PIT interrupts */
|
||||
/* and clear int. status */
|
||||
m860.piscr = M860_PISCR_PIRQ(0) |
|
||||
M860_PISCR_PTE | M860_PISCR_PS | M860_PISCR_PIE;
|
||||
|
||||
m860.simask |= M860_SIMASK_LVM0;
|
||||
}
|
||||
atexit(Clock_exit);
|
||||
}
|
||||
|
||||
void
|
||||
ReInstall_clock(rtems_isr_entry new_clock_isr)
|
||||
{
|
||||
rtems_isr_entry previous_isr;
|
||||
rtems_unsigned32 isrlevel = 0;
|
||||
|
||||
rtems_interrupt_disable(isrlevel);
|
||||
|
||||
rtems_interrupt_catch(new_clock_isr, PPC_IRQ_LVL0, &previous_isr);
|
||||
|
||||
rtems_interrupt_enable(isrlevel);
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
* Called via atexit()
|
||||
* Remove the clock interrupt handler by setting handler to NULL
|
||||
*/
|
||||
void
|
||||
Clock_exit(void)
|
||||
{
|
||||
if ( BSP_Configuration.ticks_per_timeslice ) {
|
||||
/* disable PIT and PIT interrupts */
|
||||
m860.piscr &= ~(M860_PISCR_PTE | M860_PISCR_PIE);
|
||||
|
||||
(void) set_vector(0, PPC_IRQ_LVL0, 1);
|
||||
}
|
||||
}
|
||||
|
||||
rtems_device_driver Clock_initialize(
|
||||
rtems_device_major_number major,
|
||||
rtems_device_minor_number minor,
|
||||
void *pargp
|
||||
)
|
||||
{
|
||||
Install_clock( Clock_isr );
|
||||
|
||||
/*
|
||||
* make major/minor avail to others such as shared memory driver
|
||||
*/
|
||||
|
||||
rtems_clock_major = major;
|
||||
rtems_clock_minor = minor;
|
||||
|
||||
return RTEMS_SUCCESSFUL;
|
||||
}
|
||||
|
||||
rtems_device_driver Clock_control(
|
||||
rtems_device_major_number major,
|
||||
rtems_device_minor_number minor,
|
||||
void *pargp
|
||||
)
|
||||
{
|
||||
rtems_libio_ioctl_args_t *args = pargp;
|
||||
|
||||
if (args == 0)
|
||||
goto done;
|
||||
|
||||
/*
|
||||
* This is hokey, but until we get a defined interface
|
||||
* to do this, it will just be this simple...
|
||||
*/
|
||||
|
||||
if (args->command == rtems_build_name('I', 'S', 'R', ' ')) {
|
||||
Clock_isr(PPC_IRQ_LVL0);
|
||||
}
|
||||
else if (args->command == rtems_build_name('N', 'E', 'W', ' ')) {
|
||||
ReInstall_clock(args->buffer);
|
||||
}
|
||||
|
||||
done:
|
||||
return RTEMS_SUCCESSFUL;
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user