1 | /* |
---|
2 | * AT91RM9200 clock specific using the System Timer |
---|
3 | * |
---|
4 | * Copyright (c) 2003 by Cogent Computer Systems |
---|
5 | * Written by Mike Kelly <mike@cogcomp.com> |
---|
6 | * and Jay Monkman <jtm@lopingdog.com> |
---|
7 | * |
---|
8 | * The license and distribution terms for this file may be |
---|
9 | * found in the file LICENSE in this distribution or at |
---|
10 | * |
---|
11 | * http://www.rtems.com/license/LICENSE. |
---|
12 | * |
---|
13 | * |
---|
14 | * $Id$ |
---|
15 | */ |
---|
16 | #include <rtems.h> |
---|
17 | #include <rtems/clockdrv.h> |
---|
18 | #include <rtems/libio.h> |
---|
19 | |
---|
20 | #include <stdlib.h> |
---|
21 | #include <bsp.h> |
---|
22 | #include <irq.h> |
---|
23 | #include <at91rm9200.h> |
---|
24 | #include <at91rm9200_pmc.h> |
---|
25 | |
---|
26 | |
---|
27 | static unsigned long st_pimr_reload; |
---|
28 | |
---|
29 | /** |
---|
30 | * Enables clock interrupt. |
---|
31 | * |
---|
32 | * If the interrupt is always on, this can be a NOP. |
---|
33 | */ |
---|
34 | static void clock_isr_on(const rtems_irq_connect_data *unused) |
---|
35 | { |
---|
36 | /* enable timer interrupt */ |
---|
37 | ST_REG(ST_IER) = ST_SR_PITS; |
---|
38 | } |
---|
39 | |
---|
40 | /** |
---|
41 | * Disables clock interrupts |
---|
42 | * |
---|
43 | * If the interrupt is always on, this can be a NOP. |
---|
44 | */ |
---|
45 | static void clock_isr_off(const rtems_irq_connect_data *unused) |
---|
46 | { |
---|
47 | /* disable timer interrupt */ |
---|
48 | ST_REG(ST_IDR) = ST_SR_PITS; |
---|
49 | return; |
---|
50 | } |
---|
51 | |
---|
52 | /** |
---|
53 | * Tests to see if clock interrupt is enabled, and returns 1 if so. |
---|
54 | * If interrupt is not enabled, returns 0. |
---|
55 | * |
---|
56 | * If the interrupt is always on, this always returns 1. |
---|
57 | */ |
---|
58 | static int clock_isr_is_on(const rtems_irq_connect_data *irq) |
---|
59 | { |
---|
60 | /* check timer interrupt */ |
---|
61 | return ST_REG(ST_IMR) & ST_SR_PITS; |
---|
62 | } |
---|
63 | |
---|
64 | rtems_isr Clock_isr(rtems_vector_number vector); |
---|
65 | |
---|
66 | /* Replace the first value with the clock's interrupt name. */ |
---|
67 | rtems_irq_connect_data clock_isr_data = {AT91RM9200_INT_SYSIRQ, |
---|
68 | (rtems_irq_hdl)Clock_isr, |
---|
69 | NULL, |
---|
70 | clock_isr_on, |
---|
71 | clock_isr_off, |
---|
72 | clock_isr_is_on}; |
---|
73 | |
---|
74 | |
---|
75 | #define Clock_driver_support_install_isr( _new, _old ) \ |
---|
76 | do { \ |
---|
77 | (_old) = NULL; \ |
---|
78 | BSP_install_rtems_irq_handler(&clock_isr_data); \ |
---|
79 | } while(0) |
---|
80 | |
---|
81 | uint16_t st_pimr_value; |
---|
82 | void Clock_driver_support_initialize_hardware(void) |
---|
83 | { |
---|
84 | uint32_t st_str; |
---|
85 | int slck; |
---|
86 | |
---|
87 | /* the system timer is driven from SLCK */ |
---|
88 | slck = at91rm9200_get_slck(); |
---|
89 | st_pimr_value = |
---|
90 | (((rtems_configuration_get_microseconds_per_tick() * slck) + (1000000/2))/ 1000000); |
---|
91 | st_pimr_reload = st_pimr_value; |
---|
92 | |
---|
93 | /* read the status to clear the int */ |
---|
94 | st_str = ST_REG(ST_SR); |
---|
95 | |
---|
96 | /* set priority */ |
---|
97 | AIC_SMR_REG(AIC_SMR_SYSIRQ) = AIC_SMR_PRIOR(0x7); |
---|
98 | |
---|
99 | /* set the timer value */ |
---|
100 | ST_REG(ST_PIMR) = st_pimr_reload; |
---|
101 | } |
---|
102 | |
---|
103 | uint32_t bsp_clock_nanoseconds_since_last_tick(void) |
---|
104 | { |
---|
105 | uint16_t slck_counts; |
---|
106 | |
---|
107 | slck_counts = st_pimr_value - st_pimr_reload; |
---|
108 | return (rtems_configuration_get_microseconds_per_tick() * slck_counts * 1000) |
---|
109 | / st_pimr_value; |
---|
110 | } |
---|
111 | |
---|
112 | #define Clock_driver_nanoseconds_since_last_tick \ |
---|
113 | bsp_clock_nanoseconds_since_last_tick |
---|
114 | |
---|
115 | #define CLOCK_VECTOR 0 |
---|
116 | |
---|
117 | #define Clock_driver_support_at_tick() \ |
---|
118 | do { \ |
---|
119 | uint32_t st_str; \ |
---|
120 | \ |
---|
121 | /* read the status to clear the int */ \ |
---|
122 | st_str = ST_REG(ST_SR); \ |
---|
123 | } while (0) |
---|
124 | |
---|
125 | void Clock_driver_support_shutdown_hardware( void ) |
---|
126 | { |
---|
127 | BSP_remove_rtems_irq_handler(&clock_isr_data); |
---|
128 | } |
---|
129 | |
---|
130 | #include "../../../../libbsp/shared/clockdrv_shell.h" |
---|