1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
|
/**
* @file
*
* @ingroup bsp_clock
*
* @brief or1ksim clock support.
*/
/*
* or1ksim Clock driver
*
* COPYRIGHT (c) 2014 Hesham ALMatary <heshamelmatary@gmail.com>
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE
*/
#include <rtems.h>
#include <bsp.h>
#include <bsp/irq.h>
#include <bsp/or1ksim.h>
#include <rtems/score/cpu.h>
#include <rtems/score/or1k-utility.h>
/* The number of clock cycles before generating a tick timer interrupt. */
#define TTMR_NUM_OF_CLOCK_TICKS_INTERRUPT 0x09ED9
#define OR1KSIM_CLOCK_CYCLE_TIME_NANOSECONDS 10
/* CPU counter */
static CPU_Counter_ticks cpu_counter_ticks;
/* This prototype is added here to Avoid warnings */
void Clock_isr(void *arg);
static void or1ksim_clock_at_tick(void)
{
uint32_t TTMR;
/* For TTMR register,
* The least significant 28 bits are the number of clock cycles
* before generating a tick timer interrupt. While the most
* significant 4 bits are used for mode configuration, tick timer
* interrupt enable and pending interrupts status.
*/
TTMR = (CPU_OR1K_SPR_TTMR_MODE_RESTART | CPU_OR1K_SPR_TTMR_IE |
(TTMR_NUM_OF_CLOCK_TICKS_INTERRUPT & CPU_OR1K_SPR_TTMR_TP_MASK)
) & ~(CPU_OR1K_SPR_TTMR_IP);
_OR1K_mtspr(CPU_OR1K_SPR_TTMR, TTMR);
_OR1K_mtspr(CPU_OR1K_SPR_TTCR, 0);
cpu_counter_ticks += TTMR_NUM_OF_CLOCK_TICKS_INTERRUPT;
}
static void or1ksim_clock_handler_install(proc_ptr new_isr, proc_ptr old_isr)
{
rtems_status_code sc = RTEMS_SUCCESSFUL;
old_isr = NULL;
_CPU_ISR_install_vector(OR1K_EXCEPTION_TICK_TIMER,
new_isr,
old_isr);
if (sc != RTEMS_SUCCESSFUL) {
rtems_fatal_error_occurred(0xdeadbeef);
}
}
static void or1ksim_clock_initialize(void)
{
uint32_t TTMR;
/* For TTMR register,
* The least significant 28 bits are the number of clock cycles
* before generating a tick timer interrupt. While the most
* significant 4 bits are used for mode configuration, tick timer
* interrupt enable and pending interrupts status.
*/
/* FIXME: Long interval should pass since initializing the tick timer
* registers fires exceptions dispite interrupts has not been enabled yet.
*/
TTMR = (CPU_OR1K_SPR_TTMR_MODE_RESTART | CPU_OR1K_SPR_TTMR_IE |
(0xFFED9 & CPU_OR1K_SPR_TTMR_TP_MASK)
) & ~(CPU_OR1K_SPR_TTMR_IP);
_OR1K_mtspr(CPU_OR1K_SPR_TTMR, TTMR);
_OR1K_mtspr(CPU_OR1K_SPR_TTCR, 0);
/* Initialize CPU Counter */
cpu_counter_ticks = 0;
}
static void or1ksim_clock_cleanup(void)
{
uint32_t sr;
sr = _OR1K_mfspr(CPU_OR1K_SPR_SR);
/* Disable tick timer exceptions */
_OR1K_mtspr(CPU_OR1K_SPR_SR, (sr & ~CPU_OR1K_SPR_SR_IEE)
& ~CPU_OR1K_SPR_SR_TEE);
/* Invalidate tick timer config registers */
_OR1K_mtspr(CPU_OR1K_SPR_TTCR, 0);
_OR1K_mtspr(CPU_OR1K_SPR_TTMR, 0);
}
/*
* Return the nanoseconds since last tick
*/
static uint32_t or1ksim_clock_nanoseconds_since_last_tick(void)
{
return
TTMR_NUM_OF_CLOCK_TICKS_INTERRUPT * OR1KSIM_CLOCK_CYCLE_TIME_NANOSECONDS;
}
CPU_Counter_ticks _CPU_Counter_read(void)
{
uint32_t ticks_since_last_timer_interrupt;
ticks_since_last_timer_interrupt = _OR1K_mfspr(CPU_OR1K_SPR_TTCR);
return cpu_counter_ticks + ticks_since_last_timer_interrupt;
}
CPU_Counter_ticks _CPU_Counter_difference(
CPU_Counter_ticks second,
CPU_Counter_ticks first
)
{
return second - first;
}
#define Clock_driver_support_at_tick() or1ksim_clock_at_tick()
#define Clock_driver_support_initialize_hardware() or1ksim_clock_initialize()
#define Clock_driver_support_install_isr(isr, old_isr) \
do { \
old_isr = NULL; \
or1ksim_clock_handler_install(isr, old_isr); \
} while (0)
#define Clock_driver_support_shutdown_hardware() or1ksim_clock_cleanup()
#define Clock_driver_nanoseconds_since_last_tick \
or1ksim_clock_nanoseconds_since_last_tick
#include "../../../shared/clockdrv_shell.h"
|
