Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Acked-by: Peter Pearse <peter.pearse@arm.com>master
parent
86baa085c5
commit
2bcef0723e
@ -0,0 +1,171 @@ |
|||||||
|
/*
|
||||||
|
* (C) Copyright 2002 |
||||||
|
* Sysgo Real-Time Solutions, GmbH <www.elinos.com> |
||||||
|
* Marius Groeger <mgroeger@sysgo.de> |
||||||
|
* |
||||||
|
* (C) Copyright 2002 |
||||||
|
* David Mueller, ELSOFT AG, <d.mueller@elsoft.ch> |
||||||
|
* |
||||||
|
* (C) Copyright 2003 |
||||||
|
* Texas Instruments, <www.ti.com> |
||||||
|
* Kshitij Gupta <Kshitij@ti.com> |
||||||
|
* |
||||||
|
* (C) Copyright 2004 |
||||||
|
* ARM Ltd. |
||||||
|
* Philippe Robin, <philippe.robin@arm.com> |
||||||
|
* |
||||||
|
* See file CREDITS for list of people who contributed to this |
||||||
|
* project. |
||||||
|
* |
||||||
|
* 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; either version 2 of |
||||||
|
* the License, or (at your option) any later version. |
||||||
|
* |
||||||
|
* 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, write to the Free Software |
||||||
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
||||||
|
* MA 02111-1307 USA |
||||||
|
*/ |
||||||
|
|
||||||
|
#include <common.h> |
||||||
|
|
||||||
|
/* The Integrator/AP timer1 is clocked at 24MHz
|
||||||
|
* can be divided by 16 or 256 |
||||||
|
* and is a 16-bit counter |
||||||
|
*/ |
||||||
|
/* U-Boot expects a 32 bit timer running at CONFIG_SYS_HZ*/ |
||||||
|
static ulong timestamp; /* U-Boot ticks since startup */ |
||||||
|
static ulong total_count = 0; /* Total timer count */ |
||||||
|
static ulong lastdec; /* Timer reading at last call */ |
||||||
|
static ulong div_clock = 256; /* Divisor applied to the timer clock */ |
||||||
|
static ulong div_timer = 1; /* Divisor to convert timer reading
|
||||||
|
* change to U-Boot ticks |
||||||
|
*/ |
||||||
|
/* CONFIG_SYS_HZ = CONFIG_SYS_HZ_CLOCK/(div_clock * div_timer) */ |
||||||
|
|
||||||
|
#define TIMER_LOAD_VAL 0x0000FFFFL |
||||||
|
#define READ_TIMER ((*(volatile ulong *)(CONFIG_SYS_TIMERBASE+4)) & 0x0000FFFFL) |
||||||
|
|
||||||
|
/* all function return values in U-Boot ticks i.e. (1/CONFIG_SYS_HZ) sec
|
||||||
|
* - unless otherwise stated |
||||||
|
*/ |
||||||
|
|
||||||
|
/* starts a counter
|
||||||
|
* - the Integrator/AP timer issues an interrupt |
||||||
|
* each time it reaches zero |
||||||
|
*/ |
||||||
|
int timer_init (void) |
||||||
|
{ |
||||||
|
/* Load timer with initial value */ |
||||||
|
*(volatile ulong *)(CONFIG_SYS_TIMERBASE + 0) = TIMER_LOAD_VAL; |
||||||
|
/* Set timer to be
|
||||||
|
* enabled 1 |
||||||
|
* free-running 0 |
||||||
|
* XX 00 |
||||||
|
* divider 256 10 |
||||||
|
* XX 00 |
||||||
|
*/ |
||||||
|
*(volatile ulong *)(CONFIG_SYS_TIMERBASE + 8) = 0x00000088; |
||||||
|
total_count = 0; |
||||||
|
/* init the timestamp and lastdec value */ |
||||||
|
reset_timer_masked(); |
||||||
|
|
||||||
|
div_timer = CONFIG_SYS_HZ_CLOCK / CONFIG_SYS_HZ; |
||||||
|
div_timer /= div_clock; |
||||||
|
|
||||||
|
return (0); |
||||||
|
} |
||||||
|
|
||||||
|
/*
|
||||||
|
* timer without interrupts |
||||||
|
*/ |
||||||
|
void reset_timer (void) |
||||||
|
{ |
||||||
|
reset_timer_masked (); |
||||||
|
} |
||||||
|
|
||||||
|
ulong get_timer (ulong base_ticks) |
||||||
|
{ |
||||||
|
return get_timer_masked () - base_ticks; |
||||||
|
} |
||||||
|
|
||||||
|
void set_timer (ulong ticks) |
||||||
|
{ |
||||||
|
timestamp = ticks; |
||||||
|
total_count = ticks * div_timer; |
||||||
|
reset_timer_masked(); |
||||||
|
} |
||||||
|
|
||||||
|
/* delay x useconds */ |
||||||
|
void udelay (unsigned long usec) |
||||||
|
{ |
||||||
|
ulong tmo, tmp; |
||||||
|
|
||||||
|
/* Convert to U-Boot ticks */ |
||||||
|
tmo = usec * CONFIG_SYS_HZ; |
||||||
|
tmo /= (1000000L); |
||||||
|
|
||||||
|
tmp = get_timer_masked(); /* get current timestamp */ |
||||||
|
tmo += tmp; /* wake up timestamp */ |
||||||
|
|
||||||
|
while (get_timer_masked () < tmo) { /* loop till event */ |
||||||
|
/*NOP*/; |
||||||
|
} |
||||||
|
} |
||||||
|
|
||||||
|
void reset_timer_masked (void) |
||||||
|
{ |
||||||
|
/* reset time */ |
||||||
|
lastdec = READ_TIMER; /* capture current decrementer value */ |
||||||
|
timestamp = 0; /* start "advancing" time stamp from 0 */ |
||||||
|
} |
||||||
|
|
||||||
|
/* converts the timer reading to U-Boot ticks */ |
||||||
|
/* the timestamp is the number of ticks since reset */ |
||||||
|
/* This routine does not detect wraps unless called regularly
|
||||||
|
ASSUMES a call at least every 16 seconds to detect every reload */ |
||||||
|
ulong get_timer_masked (void) |
||||||
|
{ |
||||||
|
ulong now = READ_TIMER; /* current count */ |
||||||
|
|
||||||
|
if (now > lastdec) { |
||||||
|
/* Must have wrapped */ |
||||||
|
total_count += lastdec + TIMER_LOAD_VAL + 1 - now; |
||||||
|
} else { |
||||||
|
total_count += lastdec - now; |
||||||
|
} |
||||||
|
lastdec = now; |
||||||
|
timestamp = total_count/div_timer; |
||||||
|
|
||||||
|
return timestamp; |
||||||
|
} |
||||||
|
|
||||||
|
/* waits specified delay value and resets timestamp */ |
||||||
|
void udelay_masked (unsigned long usec) |
||||||
|
{ |
||||||
|
udelay(usec); |
||||||
|
} |
||||||
|
|
||||||
|
/*
|
||||||
|
* This function is derived from PowerPC code (read timebase as long long). |
||||||
|
* On ARM it just returns the timer value. |
||||||
|
*/ |
||||||
|
unsigned long long get_ticks(void) |
||||||
|
{ |
||||||
|
return get_timer(0); |
||||||
|
} |
||||||
|
|
||||||
|
/*
|
||||||
|
* Return the timebase clock frequency |
||||||
|
* i.e. how often the timer decrements |
||||||
|
*/ |
||||||
|
ulong get_tbclk (void) |
||||||
|
{ |
||||||
|
return CONFIG_SYS_HZ_CLOCK/div_clock; |
||||||
|
} |
Loading…
Reference in new issue