diff options
Diffstat (limited to 'c/src/lib/libbsp/no_cpu/no_bsp/clock/ckinit.c')
-rw-r--r-- | c/src/lib/libbsp/no_cpu/no_bsp/clock/ckinit.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/no_cpu/no_bsp/clock/ckinit.c b/c/src/lib/libbsp/no_cpu/no_bsp/clock/ckinit.c new file mode 100644 index 0000000000..1925ceb3f3 --- /dev/null +++ b/c/src/lib/libbsp/no_cpu/no_bsp/clock/ckinit.c @@ -0,0 +1,191 @@ +/* ckinit.c + * + * This file provides a template for the clock device driver initialization. + * + * COPYRIGHT (c) 1989-1997. + * On-Line Applications Research Corporation (OAR). + * Copyright assigned to U.S. Government, 1994. + * + * The license and distribution terms for this file may in + * the file LICENSE in this distribution or at + * http://www.OARcorp.com/rtems/license.html. + * + * $Id$ + */ + +#include <stdlib.h> + +#include <rtems.h> +#include <rtems/libio.h> +#include <bsp.h> + +void Clock_exit( void ); +rtems_isr Clock_isr( rtems_vector_number vector ); + + +/* + * The interrupt vector number associated with the clock tick device + * driver. + */ + +#define CLOCK_VECTOR 4 + +/* + * Clock_driver_ticks is a monotonically increasing counter of the + * number of clock ticks since the driver was initialized. + */ + +volatile rtems_unsigned32 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. + */ + +rtems_unsigned32 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; + +/* + * The previous ISR on this clock tick interrupt vector. + */ + +rtems_isr_entry Old_ticker; + +void Clock_exit( void ); + + +/* + * Isr Handler + */ + +rtems_isr Clock_isr( + rtems_vector_number vector +) +{ +/* + * bump the number of clock driver ticks since initialization + * + * determine if it is time to announce the passing of tick as configured + * to RTEMS through the rtems_clock_tick directive + * + * perform any timer dependent tasks + */ +} + +/* + * Install_clock + * + * Install a clock tick handler and reprograms the chip. This + * is used to initially establish the clock tick. + */ + +void Install_clock( + rtems_isr_entry clock_isr +) +{ + /* + * Initialize the clock tick device driver variables + */ + + Clock_driver_ticks = 0; + Clock_isrs = BSP_Configuration.microseconds_per_tick / 1000; + + /* + * If ticks_per_timeslice is configured as non-zero, then the user + * wants a clock tick. + */ + + if ( BSP_Configuration.ticks_per_timeslice ) { + Old_ticker = (rtems_isr_entry) set_vector( clock_isr, CLOCK_VECTOR, 1 ); + /* + * Hardware specific initialize goes here + */ + + /* XXX */ + } + + /* + * Schedule the clock cleanup routine to execute if the application exits. + */ + + atexit( Clock_exit ); +} + +/* + * Clean up before the application exits + */ + +void Clock_exit( void ) +{ + if ( BSP_Configuration.ticks_per_timeslice ) { + + /* XXX: turn off the timer interrupts */ + + /* XXX: If necessary, restore the old vector */ + } +} + +/* + * 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( 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_unsigned32 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); + } + 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; +} |