bios: timer support

This commit is contained in:
Sebastien Bourdeauducq 2012-05-21 22:56:21 +02:00
parent e33399de82
commit 275ed9cd9c
3 changed files with 135 additions and 0 deletions

63
software/bios/timer.c Normal file
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/*
* Milkymist SoC (Software)
* Copyright (C) 2012 Sebastien Bourdeauducq
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <hw/timer.h>
#include "timer.h"
unsigned int get_system_frequency(void)
{
return 83333333; /* TODO */
}
void timer_enable(int en)
{
CSR_TIMER0_EN = en;
}
unsigned int timer_get(void)
{
return (CSR_TIMER0_COUNT3 << 24)
|(CSR_TIMER0_COUNT2 << 16)
|(CSR_TIMER0_COUNT1 << 8)
|CSR_TIMER0_COUNT0;
}
void timer_set_counter(unsigned int value)
{
CSR_TIMER0_COUNT3 = (value & 0xff000000) >> 24;
CSR_TIMER0_COUNT2 = (value & 0x00ff0000) >> 16;
CSR_TIMER0_COUNT1 = (value & 0x0000ff00) >> 8;
CSR_TIMER0_COUNT0 = value & 0x000000ff;
}
void timer_set_reload(unsigned int value)
{
CSR_TIMER0_RELOAD3 = (value & 0xff000000) >> 24;
CSR_TIMER0_RELOAD2 = (value & 0x00ff0000) >> 16;
CSR_TIMER0_RELOAD1 = (value & 0x0000ff00) >> 8;
CSR_TIMER0_RELOAD0 = value & 0x000000ff;
}
void busy_wait(unsigned int ds)
{
timer_enable(0);
timer_set_reload(0);
timer_set_counter(get_system_frequency()/10*ds);
timer_enable(1);
while(timer_get());
}

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software/bios/timer.h Normal file
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/*
* Milkymist SoC (Software)
* Copyright (C) 2012 Sebastien Bourdeauducq
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __TIMER_H
#define __TIMER_H
unsigned int get_system_frequency(void);
void timer_enable(int en);
unsigned int timer_get(void);
void timer_set_counter(unsigned int value);
void timer_set_reload(unsigned int value);
void busy_wait(unsigned int ms);
#endif /* __TIMER_H */

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/*
* Milkymist SoC (Software)
* Copyright (C) 2007, 2008, 2009, 2010, 2012 Sebastien Bourdeauducq
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 3 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __HW_TIMER_H
#define __HW_TIMER_H
#include <hw/common.h>
#include <csrbase.h>
#define TIMER0_CSR(x) MMPTR(TIMER0_BASE+(x))
#define CSR_TIMER0_EN TIMER0_CSR(0x00)
#define CSR_TIMER0_COUNT3 TIMER0_CSR(0x04)
#define CSR_TIMER0_COUNT2 TIMER0_CSR(0x08)
#define CSR_TIMER0_COUNT1 TIMER0_CSR(0x0C)
#define CSR_TIMER0_COUNT0 TIMER0_CSR(0x10)
#define CSR_TIMER0_RELOAD3 TIMER0_CSR(0x14)
#define CSR_TIMER0_RELOAD2 TIMER0_CSR(0x18)
#define CSR_TIMER0_RELOAD1 TIMER0_CSR(0x1C)
#define CSR_TIMER0_RELOAD0 TIMER0_CSR(0x20)
#define CSR_TIMER0_EV_STAT TIMER0_CSR(0x24)
#define CSR_TIMER0_EV_PENDING TIMER0_CSR(0x28)
#define CSR_TIMER0_EV_ENABLE TIMER0_CSR(0x2C)
#define TIMER0_EV 0x1
#endif /* __HW_TIMER_H */