1 | /* |
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2 | * Use the last periodic interval timer (PIT2) as the system clock. |
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3 | */ |
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4 | |
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5 | #include <rtems.h> |
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6 | #include <rtems/timecounter.h> |
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7 | #include <bsp.h> |
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8 | |
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9 | /* |
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10 | * Use INTC1 base |
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11 | */ |
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12 | #define CLOCK_VECTOR (128+46) |
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13 | |
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14 | static rtems_timecounter_simple mcf5329_tc; |
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15 | |
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16 | static uint32_t mcf5329_tc_get(rtems_timecounter_simple *tc) |
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17 | { |
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18 | return MCF_PIT3_PCNTR; |
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19 | } |
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20 | |
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21 | static bool mcf5329_tc_is_pending(rtems_timecounter_simple *tc) |
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22 | { |
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23 | return (MCF_PIT3_PCSR & MCF_PIT_PCSR_PIF) != 0; |
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24 | } |
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25 | |
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26 | static uint32_t mcf5329_tc_get_timecount(struct timecounter *tc) |
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27 | { |
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28 | return rtems_timecounter_simple_downcounter_get( |
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29 | tc, |
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30 | mcf5329_tc_get, |
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31 | mcf5329_tc_is_pending |
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32 | ); |
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33 | } |
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34 | |
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35 | static void mcf5329_tc_at_tick(rtems_timecounter_simple *tc) |
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36 | { |
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37 | MCF_PIT3_PCSR |= MCF_PIT_PCSR_PIF; |
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38 | } |
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39 | |
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40 | static void mcf5329_tc_tick(void) |
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41 | { |
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42 | rtems_timecounter_simple_downcounter_tick( |
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43 | &mcf5329_tc, |
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44 | mcf5329_tc_get, |
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45 | mcf5329_tc_at_tick |
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46 | ); |
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47 | } |
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48 | |
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49 | /* |
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50 | * Attach clock interrupt handler |
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51 | */ |
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52 | #define Clock_driver_support_install_isr( _new ) \ |
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53 | set_vector(_new, CLOCK_VECTOR, 1) |
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54 | |
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55 | /* |
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56 | * Turn off the clock |
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57 | */ |
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58 | #define Clock_driver_support_shutdown_hardware() \ |
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59 | do { \ |
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60 | MCF_PIT3_PCSR &= ~MCF_PIT_PCSR_EN; \ |
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61 | } while (0) |
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62 | |
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63 | /* |
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64 | * Set up the clock hardware |
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65 | * |
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66 | * We need to have 1 interrupt every rtems_configuration_get_microseconds_per_tick() |
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67 | */ |
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68 | static void Clock_driver_support_initialize_hardware(void) |
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69 | { |
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70 | int level; |
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71 | uint32_t pmr; |
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72 | uint32_t preScaleCode = 0; |
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73 | uint32_t clk = bsp_get_BUS_clock_speed(); |
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74 | uint32_t tps = 1000000 / rtems_configuration_get_microseconds_per_tick(); |
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75 | |
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76 | while (preScaleCode < 15) { |
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77 | pmr = (clk >> preScaleCode) / tps; |
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78 | if (pmr < (1 << 15)) |
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79 | break; |
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80 | preScaleCode++; |
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81 | } |
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82 | MCF_INTC1_ICR46 = MCF_INTC_ICR_IL(PIT3_IRQ_LEVEL); |
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83 | |
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84 | rtems_interrupt_disable(level); |
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85 | MCF_INTC1_IMRH &= ~MCF_INTC_IMRH_INT_MASK46; |
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86 | MCF_PIT3_PCSR &= ~MCF_PIT_PCSR_EN; |
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87 | rtems_interrupt_enable(level); |
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88 | |
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89 | MCF_PIT3_PCSR = MCF_PIT_PCSR_PRE(preScaleCode) | |
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90 | MCF_PIT_PCSR_OVW | MCF_PIT_PCSR_PIE | MCF_PIT_PCSR_RLD; |
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91 | MCF_PIT3_PMR = pmr; |
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92 | MCF_PIT3_PCSR = MCF_PIT_PCSR_PRE(preScaleCode) | |
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93 | MCF_PIT_PCSR_PIE | MCF_PIT_PCSR_RLD | MCF_PIT_PCSR_EN; |
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94 | |
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95 | rtems_timecounter_simple_install( |
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96 | &mcf5329_tc, |
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97 | clk >> preScaleCode, |
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98 | pmr, |
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99 | mcf5329_tc_get_timecount |
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100 | ); |
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101 | } |
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102 | |
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103 | #define Clock_driver_timecounter_tick() mcf5329_tc_tick() |
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104 | |
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105 | #include "../../../shared/dev/clock/clockimpl.h" |
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