[7d33199] | 1 | /* |
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| 2 | * LPC22XX clock specific using the System Timer |
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| 3 | * set the Time0 |
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| 4 | * This is hardware specific part of the clock driver. At the end of this |
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| 5 | * file, the generic part of the driver is #included. |
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| 6 | * |
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| 7 | * The license and distribution terms for this file may be |
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| 8 | * found in the file LICENSE in this distribution or at |
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| 9 | * |
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[61e293b6] | 10 | * http://www.rtems.com/license/LICENSE. |
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[7d33199] | 11 | * |
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| 12 | * |
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[6edbd66] | 13 | * $Id$ |
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[7d33199] | 14 | */ |
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| 15 | #include <rtems.h> |
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| 16 | #include <bsp.h> |
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| 17 | #include <irq.h> |
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| 18 | #include <lpc22xx.h> |
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| 19 | #include <rtems/bspIo.h> /* for printk */ |
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| 20 | |
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| 21 | /* this is defined in ../../../shared/clockdrv_shell.c */ |
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| 22 | rtems_isr Clock_isr(rtems_vector_number vector); |
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| 23 | static void clock_isr_on(const rtems_irq_connect_data *unused); |
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| 24 | static void clock_isr_off(const rtems_irq_connect_data *unused); |
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| 25 | static int clock_isr_is_on(const rtems_irq_connect_data *irq); |
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| 26 | |
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| 27 | /* Replace the first value with the clock's interrupt name. */ |
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| 28 | rtems_irq_connect_data clock_isr_data = {LPC22xx_INTERRUPT_TIMER0, |
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| 29 | (rtems_irq_hdl)Clock_isr, |
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| 30 | clock_isr_on, |
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| 31 | clock_isr_off, |
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| 32 | clock_isr_is_on, |
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| 33 | 3, /* unused for ARM cpus */ |
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| 34 | 0 }; /* unused for ARM cpus */ |
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| 35 | |
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| 36 | /* If you follow the code, this is never used, so any value |
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| 37 | * should work |
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| 38 | */ |
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| 39 | #define CLOCK_VECTOR 0 |
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| 40 | |
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| 41 | |
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| 42 | |
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| 43 | /*use the /shared/clockdrv_shell.c code template */ |
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| 44 | |
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| 45 | /** |
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| 46 | * When we get the clock interrupt |
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| 47 | * - clear the interrupt bit? |
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| 48 | * - restart the timer? |
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| 49 | */ |
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| 50 | #define Clock_driver_support_at_tick() \ |
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| 51 | do { \ |
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| 52 | if (!(T0IR & 0x01)) return; \ |
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| 53 | T0IR = 0x01; \ |
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| 54 | VICVectAddr = 0x00;\ |
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| 55 | } while(0) |
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| 56 | |
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| 57 | /** |
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| 58 | * Installs the clock ISR. You shouldn't need to change this. |
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| 59 | */ |
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| 60 | #define Clock_driver_support_install_isr( _new, _old ) \ |
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| 61 | do { \ |
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| 62 | (_old) = NULL; \ |
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| 63 | BSP_install_rtems_irq_handler(&clock_isr_data); \ |
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| 64 | } while(0) |
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| 65 | |
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| 66 | |
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| 67 | /** |
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| 68 | * Initialize the hardware for the clock |
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| 69 | * - Set the frequency |
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| 70 | * - enable it |
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| 71 | * - clear any pending interrupts |
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| 72 | * |
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| 73 | * Since you may want the clock always running, you can |
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| 74 | * enable interrupts here. If you do so, the clock_isr_on(), |
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| 75 | * clock_isr_off(), and clock_isr_is_on() functions can be |
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| 76 | * NOPs. |
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| 77 | */ |
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| 78 | |
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| 79 | /* set timer to generate interrupt every BSP_Configuration.microseconds_per_tick */ |
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| 80 | /* MR0/(LPC22xx_Fpclk/(PR0+1)) = 10/1000 = 0.01s */ |
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| 81 | |
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| 82 | |
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| 83 | #define Clock_driver_support_initialize_hardware() \ |
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| 84 | do { \ |
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| 85 | T0TCR &= 0; /* disable and clear timer 0, set to */ \ |
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| 86 | T0PC = 0; /* TC is incrementet on every pclk.*/ \ |
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| 87 | T0MR0 = ((LPC22xx_Fpclk/1000* BSP_Configuration.microseconds_per_tick) / 1000); /* initialize the timer period and prescaler */ \ |
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| 88 | /*T0PR = (((LPC22xx_Fpclk / 1000) * BSP_Configuration.microseconds_per_tick) / 1000-1); \ */ \ |
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| 89 | T0MCR |= 0x03; /* generate interrupt when T0MR0 match T0TC and Reset Timer Count*/ \ |
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| 90 | T0EMR = 0; /*No external match*/ \ |
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| 91 | T0TCR = 1; /*enable timer0*/ \ |
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| 92 | } while (0) |
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| 93 | |
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| 94 | /** |
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| 95 | * Do whatever you need to shut the clock down and remove the |
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| 96 | * interrupt handler. Since this normally only gets called on |
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| 97 | * RTEMS shutdown, you may not need to do anything other than |
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| 98 | * remove the ISR. |
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| 99 | */ |
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| 100 | #define Clock_driver_support_shutdown_hardware() \ |
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| 101 | do { \ |
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| 102 | /* Disable timer */ \ |
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| 103 | T0TCR&=~0x02; \ |
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| 104 | BSP_remove_rtems_irq_handler(&clock_isr_data); \ |
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| 105 | } while (0) |
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| 106 | |
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| 107 | /** |
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| 108 | * Enables clock interrupt. |
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| 109 | * |
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| 110 | * If the interrupt is always on, this can be a NOP. |
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| 111 | */ |
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| 112 | static void clock_isr_on(const rtems_irq_connect_data *unused) |
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| 113 | { |
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| 114 | T0IR&=0x01; |
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| 115 | //return; |
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| 116 | } |
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| 117 | |
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| 118 | /** |
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| 119 | * Disables clock interrupts |
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| 120 | * |
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| 121 | * If the interrupt is always on, this can be a NOP. |
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| 122 | */ |
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| 123 | static void clock_isr_off(const rtems_irq_connect_data *unused) |
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| 124 | { |
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| 125 | T0IR=0x00; |
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| 126 | //return; |
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| 127 | } |
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| 128 | |
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| 129 | /** |
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| 130 | * Tests to see if clock interrupt is enabled, and returns 1 if so. |
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| 131 | * If interrupt is not enabled, returns 0. |
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| 132 | * |
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| 133 | * If the interrupt is always on, this always returns 1. |
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| 134 | */ |
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| 135 | static int clock_isr_is_on(const rtems_irq_connect_data *irq) |
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| 136 | { |
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| 137 | return T0IR & 0x01; /*MR0 mask*/ |
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| 138 | } |
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| 139 | |
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| 140 | |
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| 141 | /* Make sure to include this, and only at the end of the file */ |
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| 142 | #include "../../../../libbsp/shared/clockdrv_shell.c" |
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| 143 | |
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