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/* ckinit.c
*
* This file provides a template for the clock device driver initialization.
*
* COPYRIGHT (c) 1989-1999.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*
* $Id$
*/
#include <stdlib.h>
#include <rtems.h>
#include <rtems/libio.h>
#include <bsp.h>
static void (*old_handler)(unsigned int,unsigned int,unsigned int,unsigned int);
void Clock_exit( void );
void Clock_isr( rtems_vector_number vector,unsigned int pc,
unsigned int address, unsigned int sr);
/*
* The interrupt vector number associated with the clock tick device
* driver.
*/
#define CLOCK_VECTOR 8
/*
* Clock_driver_ticks is a monotonically increasing counter of the
* number of clock ticks since the driver was initialized.
*/
volatile uint32_t Clock_driver_ticks;
/*
* Clock_isrs is the number of clock ISRs until the next invocation of
* the RTEMS clock tick routine. The clock tick device driver
* gets an interrupt once a millisecond and counts down until the
* length of time between the user configured microseconds per tick
* has passed.
*/
uint32_t Clock_isrs; /* ISRs until next tick */
/*
* These are set by clock driver during its init
*/
rtems_device_major_number rtems_clock_major = ~0;
rtems_device_minor_number rtems_clock_minor;
void Clock_exit( void );
/* Write this to restart the Timer. Sets mode = 01,
interrupts enabled, interrupt not pending, report
at 200,000 (1 msec on 200 MHz CPU) */
static const unsigned int TTMR_RESET = 0x60030D40;
/*
* Isr Handler
*/
void Clock_isr(uint32_t vector,
uint32_t pc,
uint32_t ear,
uint32_t sr)
{
register int pending;
register int value = 0x60002710;
/* Was it us? */
asm volatile ("l.mfspr %0,r0,0x4802 \n\t" /* Read the PIC status */
"l.andi %0,%0,0x8 \n\t" : "=r" (pending));
if(pending)
{
rtems_clock_tick();
asm ("l.mtspr r0,%0,0x5000 \n\t" :: "r" (value));
}
if(old_handler)
(*old_handler)(vector,pc,ear,sr);
}
/*
* Install_clock
*
* Install a clock tick handler and reprograms the chip. This
* is used to initially establish the clock tick.
*/
void Install_clock()
{
uint32_t tmp,sr,ttmr,ttcr;
extern uint32_t Or1k_Interrupt_Vectors[16];
ttmr = TTMR_RESET; /* Reset value */
ttcr = 0; /* Start at 0 */
/*
* Initialize the clock tick device driver variables
*/
/* Make sure the Timer (interrupt 3) is enabled and
reports a high prority interrupt */
asm volatile ("l.mfspr %0,r0,0x4800 \n\t" /* Get the PIC mask */
"l.ori %0,%0,0x8 \n\t" /* Enable int 3 */
"l.mtspr r0,%0,0x4800 \n\t" /* Write back mask */
"l.mfspr %0,r0,0x4801 \n\t" /* Get priority mask */
"l.ori %0,%0,0x8 \n\t" /* Set us to high */
"l.mtspr r0,%0,0x4801 \n\t" /* Write back to PICPR */
: "=r" (tmp));
/* Generate a 1 kHz interrupt */
asm volatile ("l.mfspr %0,r0,0x11 \n\t" /* Get the current setting */
"l.addi %1,r0,-5 \n\t"
"l.and %1,%1,%0 \n\t" /* Turn off interrupts */
"l.mtspr r0,%1,0x11 \n\t" /* Set it in SR */
"l.mtspr r0,%2,0x5000\n\t" /* Set TTMR */
"l.mtspr r0,%3,0x5100\n\t" /* Set TTCR */
: "=&r" (sr), "=&r" (tmp) : "r" (ttmr), "r" (ttcr));
old_handler = (void(*)(unsigned int,unsigned int,unsigned int,unsigned int))
Or1k_Interrupt_Vectors[8];
Or1k_Interrupt_Vectors[8] = (uint32_t)Clock_isr;
asm volatile ("l.mtspr r0,%0,0x11\n\t":: "r" (sr));
Clock_driver_ticks = 0;
/*
* Schedule the clock cleanup routine to execute if the application exits.
*/
atexit( Clock_exit );
}
/*
* Clean up before the application exits
*/
void Clock_exit( void )
{
register int temp1;
register int temp2;
/* In the case of a fatal error, we should shut down
all the interrupts so we don't get woken up again. */
/* First, turn off the clock in the PIC */
asm volatile ("l.mfspr %0,r0,0x4800 \n\t" /* Get the PIC mask */
"l.addi %1,%1,-9 \n\t" /* Create a mask to disable */
"l.and %0,%1,%0 \n\t" /* Mask us out */
"l.mtspr r0,%0,0x4800 \n\t" /* Write back mask */
"l.mfspr %0,r0,0x4801 \n\t" /* Get priority mask */
"l.and %0,%1,%0 \n\t" /* Set us to low */
"l.mtspr r0,%0,0x4801 \n\t" /* Write back to PICPR */
: "=r" (temp1), "=r" (temp2));
/* Now turn off the clock at the timer */
asm volatile ("l.mtspr r0,r0,0x5000\n\t" /* Clear TTMR */
"l.mtspr r0,r0,0x5100\n\t"); /* Clear TTCR */
}
/*
* Clock_initialize
*
* Device driver entry point for clock tick driver initialization.
*/
rtems_device_driver Clock_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
Install_clock();
/*
* 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
)
{
uint32_t isrlevel;
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(CLOCK_VECTOR,0,0,0);
}
else if (args->command == rtems_build_name('N', 'E', 'W', ' '))
{
rtems_interrupt_disable( isrlevel );
(void) set_vector( args->buffer, CLOCK_VECTOR, 1 );
rtems_interrupt_enable( isrlevel );
}
done:
return RTEMS_SUCCESSFUL;
}
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