[ac7d5ef0] | 1 | /* Clock_init() |
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| 2 | * |
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| 3 | * |
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| 4 | * This is modified by Doug McBride to get it to work for the MC68EC040 |
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| 5 | * IDP board. The below comments are kept to show that some prior work |
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| 6 | * was done in the area and the modifications performed was application |
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| 7 | * specific for the IDP board to port it to. |
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| 8 | * |
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| 9 | * This routine initializes the mc68230 on the MC68EC040 board. |
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| 10 | * The tick frequency is 40 milliseconds. |
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| 11 | * |
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| 12 | * Input parameters: NONE |
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| 13 | * |
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| 14 | * Output parameters: NONE |
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| 15 | * |
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| 16 | * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994. |
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| 17 | * On-Line Applications Research Corporation (OAR). |
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| 18 | * All rights assigned to U.S. Government, 1994. |
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| 19 | * |
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| 20 | * This material may be reproduced by or for the U.S. Government pursuant |
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| 21 | * to the copyright license under the clause at DFARS 252.227-7013. This |
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| 22 | * notice must appear in all copies of this file and its derivatives. |
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| 23 | * |
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| 24 | * $Id$ |
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| 25 | */ |
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| 26 | |
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| 27 | #include <stdlib.h> |
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| 28 | |
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[88d594a] | 29 | #include <rtems.h> |
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| 30 | #include <clockdrv.h> |
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| 31 | #include <bsp.h> |
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[ac7d5ef0] | 32 | |
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| 33 | rtems_unsigned32 Clock_isrs; /* ISRs until next tick */ |
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| 34 | volatile rtems_unsigned32 Clock_driver_ticks; |
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| 35 | /* ticks since initialization */ |
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| 36 | rtems_isr_entry Old_ticker; |
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| 37 | |
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| 38 | extern rtems_configuration_table Configuration; |
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| 39 | extern void led_putnum(); |
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| 40 | void Disable_clock(); |
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| 41 | |
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| 42 | #define TIMER_VECTOR 0x4D |
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| 43 | |
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| 44 | rtems_device_driver Clock_initialize( |
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| 45 | rtems_device_major_number major, |
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| 46 | rtems_device_minor_number minor, |
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| 47 | void *pargp, |
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| 48 | rtems_id tid, |
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| 49 | rtems_unsigned32 *rval |
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| 50 | ) |
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| 51 | { |
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| 52 | Install_clock( Clock_isr ); |
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| 53 | } |
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| 54 | |
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| 55 | void ReInstall_clock( clock_isr ) |
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| 56 | rtems_isr_entry clock_isr; |
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| 57 | { |
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| 58 | rtems_unsigned32 isrlevel = 0 ; |
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| 59 | |
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| 60 | rtems_interrupt_disable( isrlevel ); |
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| 61 | (void) set_vector( clock_isr, TIMER_VECTOR, 1 ); |
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| 62 | rtems_interrupt_enable( isrlevel ); |
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| 63 | } |
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| 64 | |
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| 65 | /* The following was added for debugging purposes */ |
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| 66 | void Disable_clock() |
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| 67 | { |
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| 68 | /* Disable timer */ |
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| 69 | MC68230_WRITE (TCR, 0x00); |
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| 70 | } |
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| 71 | |
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| 72 | void Install_clock( clock_isr ) |
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| 73 | rtems_isr_entry clock_isr; |
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| 74 | { |
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| 75 | Clock_driver_ticks = 0; |
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| 76 | Clock_isrs = (int)(Configuration.microseconds_per_tick / 1000); |
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| 77 | |
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| 78 | if ( Configuration.ticks_per_timeslice ) { |
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| 79 | /* led_putnum('c'); * for debugging purposes */ |
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| 80 | Old_ticker = (rtems_isr_entry) set_vector( clock_isr, TIMER_VECTOR, 1 ); |
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| 81 | |
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| 82 | /* Disable timer for initialization */ |
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| 83 | MC68230_WRITE (TCR, 0x00); |
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| 84 | |
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| 85 | /* some PI/T initialization stuff here -- see comment in the ckisr.c |
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| 86 | file in this directory to understand why I use the values that I do */ |
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| 87 | /* Set up the interrupt vector on the MC68230 chip: |
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| 88 | TIVR = TIMER_VECTOR; */ |
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| 89 | MC68230_WRITE (TIVR, TIMER_VECTOR); |
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| 90 | |
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| 91 | /* Set CPRH through CPRL to 193 (not 203) decimal for countdown--see ckisr.c |
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| 92 | CPRH = 0x00; |
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| 93 | CPRM = 0x00; |
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| 94 | CPRL = 0xC1; */ |
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| 95 | MC68230_WRITE (CPRH, 0x00); |
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| 96 | MC68230_WRITE (CPRM, 0x00); |
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| 97 | MC68230_WRITE (CPRL, 0xC1); |
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| 98 | |
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| 99 | /* Enable timer and use it as an external periodic interrupt generator |
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| 100 | TCR = 0xA1; */ |
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| 101 | /* led_putnum('a'); * for debugging purposes */ |
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| 102 | MC68230_WRITE (TCR, 0xA1); |
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| 103 | |
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| 104 | /* |
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| 105 | * Schedule the clock cleanup routine to execute if the application exits. |
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| 106 | */ |
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| 107 | atexit( Clock_exit ); |
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| 108 | } |
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| 109 | } |
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| 110 | |
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| 111 | void Clock_exit( void ) |
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| 112 | { |
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| 113 | rtems_unsigned8 data; |
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| 114 | |
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| 115 | if ( Configuration.ticks_per_timeslice ) { |
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| 116 | |
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| 117 | /* disable timer |
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| 118 | data = TCR; |
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| 119 | TCR = (data & 0xFE); */ |
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| 120 | MC68230_READ (TCR, data); |
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| 121 | MC68230_WRITE (TCR, (data & 0xFE)); |
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| 122 | |
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| 123 | /* do not restore old vector */ |
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| 124 | } |
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| 125 | } |
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