Subversion Repositories HelenOS

Rev

Rev 2927 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
2162 stepan 1 
/*
2245 stepan 2 
 * Copyright (c) 2007 Petr Stepan
2162 stepan 3 
 * All rights reserved.
4 
 *
5 
 * Redistribution and use in source and binary forms, with or without
6 
 * modification, are permitted provided that the following conditions
7 
 * are met:
8 
 *
9 
 * - Redistributions of source code must retain the above copyright
10 
 *   notice, this list of conditions and the following disclaimer.
11 
 * - Redistributions in binary form must reproduce the above copyright
12 
 *   notice, this list of conditions and the following disclaimer in the
13 
 *   documentation and/or other materials provided with the distribution.
14 
 * - The name of the author may not be used to endorse or promote products
15 
 *   derived from this software without specific prior written permission.
16 
 *
17 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 
 */
28 
 
29 
/** @addtogroup arm32
30 
 * @{
31 
 */
32 
/** @file
2410 stepan 33 
 *  @brief Interrupts controlling routines.
2162 stepan 34 
 */
35 
 
2214 kebrt 36 
#include <arch/asm.h>
37 
#include <arch/regutils.h>
4346 svoboda 38 
#include <arch/drivers/gxemul.h>
2245 stepan 39 
#include <ddi/irq.h>
4346 svoboda 40 
#include <ddi/device.h>
2214 kebrt 41 
#include <interrupt.h>
2162 stepan 42 
 
2407 stepan 43 
/** Initial size of a table holding interrupt handlers. */
2245 stepan 44 
#define IRQ_COUNT 8
2162 stepan 45 
 
4346 svoboda 46 
static irq_t gxemul_timer_irq;
47 
 
2162 stepan 48 
/** Disable interrupts.
49 
 *
50 
 * @return Old interrupt priority level.
51 
 */
52 
ipl_t interrupts_disable(void)
53 
{
2177 stepan 54 
    ipl_t ipl = current_status_reg_read();
4346 svoboda 55 
 
2312 stepan 56 
    current_status_reg_control_write(STATUS_REG_IRQ_DISABLED_BIT | ipl);
2162 stepan 57 
 
58 
    return ipl;
59 
}
60 
 
61 
/** Enable interrupts.
62 
 *
63 
 * @return Old interrupt priority level.
64 
 */
65 
ipl_t interrupts_enable(void)
66 
{
2177 stepan 67 
    ipl_t ipl = current_status_reg_read();
4346 svoboda 68 
 
2312 stepan 69 
    current_status_reg_control_write(ipl & ~STATUS_REG_IRQ_DISABLED_BIT);
4346 svoboda 70 
 
2162 stepan 71 
    return ipl;
72 
}
73 
 
74 
/** Restore interrupt priority level.
75 
 *
76 
 * @param ipl Saved interrupt priority level.
77 
 */
78 
void interrupts_restore(ipl_t ipl)
79 
{
2343 stepan 80 
    current_status_reg_control_write(
2464 jermar 81 
        (current_status_reg_read() & ~STATUS_REG_IRQ_DISABLED_BIT) |
82 
        (ipl & STATUS_REG_IRQ_DISABLED_BIT));
2162 stepan 83 
}
84 
 
85 
/** Read interrupt priority level.
86 
 *
87 
 * @return Current interrupt priority level.
88 
 */
89 
ipl_t interrupts_read(void)
90 
{
2177 stepan 91 
    return current_status_reg_read();
2162 stepan 92 
}
93 
 
4346 svoboda 94 
/** Starts gxemul Real Time Clock device, which asserts regular interrupts.
95 
 *
96 
 * @param frequency Interrupts frequency (0 disables RTC).
97 
 */
98 
static void gxemul_timer_start(uint32_t frequency)
99 
{
100 
    *((uint32_t *) (gxemul_rtc + GXEMUL_RTC_FREQ_OFFSET))
101 
        = frequency;
102 
}
103 
 
104 
static irq_ownership_t gxemul_timer_claim(irq_t *irq)
105 
{
106 
    return IRQ_ACCEPT;
107 
}
108 
 
109 
/** Timer interrupt handler.
110 
 *
111 
 * @param irq Interrupt information.
112 
 * @param arg Not used.
113 
 */
114 
static void gxemul_timer_irq_handler(irq_t *irq)
115 
{
116 
    /*
117 
    * We are holding a lock which prevents preemption.
118 
    * Release the lock, call clock() and reacquire the lock again.
119 
    */
120 
    spinlock_unlock(&irq->lock);
121 
    clock();
122 
    spinlock_lock(&irq->lock);
123 
 
124 
    /* acknowledge tick */
125 
    *((uint32_t *) (gxemul_rtc + GXEMUL_RTC_ACK_OFFSET))
126 
        = 0;
127 
}
128 
 
2245 stepan 129 
/** Initialize basic tables for exception dispatching
130 
 * and starts the timer.
131 
 */
132 
void interrupt_init(void)
133 
{
2214 kebrt 134 
    irq_init(IRQ_COUNT, IRQ_COUNT);
4346 svoboda 135 
 
136 
    irq_initialize(&gxemul_timer_irq);
137 
    gxemul_timer_irq.devno = device_assign_devno();
138 
    gxemul_timer_irq.inr = GXEMUL_TIMER_IRQ;
139 
    gxemul_timer_irq.claim = gxemul_timer_claim;
140 
    gxemul_timer_irq.handler = gxemul_timer_irq_handler;
141 
 
142 
    irq_register(&gxemul_timer_irq);
143 
 
144 
    gxemul_timer_start(GXEMUL_TIMER_FREQ);
2214 kebrt 145 
}
146 
 
2162 stepan 147 
/** @}
148 
 */