diff options
Diffstat (limited to 'c/src/lib/libcpu/powerpc/mpc8260/clock/clock.c')
-rw-r--r-- | c/src/lib/libcpu/powerpc/mpc8260/clock/clock.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/c/src/lib/libcpu/powerpc/mpc8260/clock/clock.c b/c/src/lib/libcpu/powerpc/mpc8260/clock/clock.c new file mode 100644 index 0000000000..672ecf29da --- /dev/null +++ b/c/src/lib/libcpu/powerpc/mpc8260/clock/clock.c @@ -0,0 +1,228 @@ +/* clock.c + * + * This routine initializes the PIT on the MPC8xx. + * 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 <rtems.h> +#include <clockdrv.h> +#include <rtems/libio.h> + +#include <stdlib.h> /* for atexit() */ +#include <mpc8260.h> +#include <bsp/irq.h> + +volatile rtems_unsigned32 Clock_driver_ticks; +extern int BSP_get_clock_irq_level(); +extern int BSP_connect_clock_handler(rtems_isr_entry); +extern int BSP_disconnect_clock_handler(); + +void Clock_exit( void ); + +rtems_unsigned32 decrementer_value; + +volatile int ClockInitialised = 0; + + +/* + * 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) +{ + int clicks; + + if( ClockInitialised ) { + PPC_Get_decrementer( clicks ); + do { + clicks += decrementer_value; + PPC_Set_decrementer( clicks ); + + Clock_driver_ticks++; + rtems_clock_tick(); + } while( clicks < 100 ); + } +#if 0 + m8260.piscr |= M8260_PISCR_PS; + Clock_driver_ticks++; + rtems_clock_tick(); +#endif + + +} + +void clockOn(void* unused) +{ + + decrementer_value = rtems_configuration_get_microseconds_per_tick() * + rtems_cpu_configuration_get_clicks_per_usec() - 1; + + PPC_Set_decrementer( decrementer_value ); + Clock_driver_ticks = 0; + + ClockInitialised = 1; + + +#if 0 + unsigned desiredLevel; + rtems_unsigned32 pit_value; + + pit_value = (rtems_configuration_get_microseconds_per_tick() * + rtems_cpu_configuration_get_clicks_per_usec()) - 1 ; + + if (pit_value > 0xffff) { /* pit is only 16 bits long */ + rtems_fatal_error_occurred(-1); + } + m8260.sccr &= ~(1<<24); + m8260.pitc = pit_value; + + desiredLevel = BSP_get_clock_irq_level(); + /* set PIT irq level, enable PIT, PIT interrupts */ + /* and clear int. status */ + m8260.piscr = /*M8260_PISCR_PIRQ(desiredLevel) |*/ + M8260_PISCR_PTE | M8260_PISCR_PS | M8260_PISCR_PIE; +#endif +} +/* + * Called via atexit() + * Remove the clock interrupt handler by setting handler to NULL + */ +void +clockOff(void* unused) +{ +#if 0 + /* disable PIT and PIT interrupts */ + m8260.piscr &= ~(M8260_PISCR_PTE | M8260_PISCR_PIE); +#endif + ClockInitialised = 0; +} + +int clockIsOn(void* unused) +{ + return ClockInitialised; +#if 0 + if (m8260.piscr & M8260_PISCR_PIE) return 1; + return 0; +#endif + +} + +/* + * Called via atexit() + * Remove the clock interrupt handler by setting handler to NULL + */ +void +Clock_exit(void) +{ + (void) BSP_disconnect_clock_handler (); +} + +void Install_clock(rtems_isr_entry clock_isr) +{ + Clock_driver_ticks = 0; + + + decrementer_value = rtems_configuration_get_microseconds_per_tick() * + rtems_cpu_configuration_get_clicks_per_usec() - 1; + + PPC_Set_decrementer( decrementer_value ); + + BSP_connect_clock_handler (clock_isr); + + + ClockInitialised = 1; + + atexit(Clock_exit); + +} + +void +ReInstall_clock(rtems_isr_entry new_clock_isr) +{ + BSP_connect_clock_handler (new_clock_isr); +} + + +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(BSP_PERIODIC_TIMER); + } + else if (args->command == rtems_build_name('N', 'E', 'W', ' ')) { + ReInstall_clock(args->buffer); + } + + done: + return RTEMS_SUCCESSFUL; +} + |