94 lines
3.2 KiB
C
94 lines
3.2 KiB
C
/*
|
|
(C) Copyright IBM Corp. 2008
|
|
|
|
All rights reserved.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions are met:
|
|
|
|
* Redistributions of source code must retain the above copyright notice,
|
|
this list of conditions and the following disclaimer.
|
|
* Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in the
|
|
documentation and/or other materials provided with the distribution.
|
|
* Neither the name of IBM nor the names of its contributors may be
|
|
used to endorse or promote products derived from this software without
|
|
specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
/* SPU clock start and read library services. */
|
|
#include <spu_timer.h>
|
|
#include "spu_timer_internal.h"
|
|
|
|
/* The software managed timebase value. */
|
|
volatile uint64_t __spu_tb_val __attribute__ ((aligned (16)));
|
|
|
|
/* Timeout value of the current interval. */
|
|
volatile int __spu_tb_timeout __attribute__ ((aligned (16)));
|
|
|
|
/* Clock start count (clock is running if >0). */
|
|
volatile unsigned __spu_clock_startcnt __attribute__ ((aligned (16)));
|
|
|
|
/* Saved interrupt state from clock_start. */
|
|
volatile unsigned __spu_clock_state_was_enabled;
|
|
|
|
/* Initializes the software managed timebase, enables the decrementer event,
|
|
starts the decrementer and enables interrupts. Must be called before
|
|
clock or timer services can be used. Should only be called by base app/lib
|
|
code (not from an interrupt/timer handler).
|
|
Returns with interrupts ENABLED. */
|
|
void
|
|
spu_clock_start (void)
|
|
{
|
|
/* Increment clock start and return if it was already running. */
|
|
if (++__spu_clock_startcnt > 1)
|
|
return;
|
|
|
|
__spu_clock_state_was_enabled = spu_readch (SPU_RdMachStat) & 0x1;
|
|
|
|
spu_idisable ();
|
|
__spu_tb_timeout = CLOCK_START_VALUE;
|
|
__spu_tb_val = 0;
|
|
|
|
/* Disable, write, enable the decrementer. */
|
|
__enable_spu_decr (__spu_tb_timeout, __disable_spu_decr ());
|
|
|
|
spu_ienable ();
|
|
|
|
return;
|
|
}
|
|
|
|
/* Returns a monotonically increasing, 64-bit counter, in timebase units,
|
|
relative to the last call to spu_clock_start(). */
|
|
uint64_t
|
|
spu_clock_read (void)
|
|
{
|
|
int64_t time;
|
|
unsigned was_enabled;
|
|
|
|
/* Return 0 if clock is off. */
|
|
if (__spu_clock_startcnt == 0)
|
|
return 0LL;
|
|
|
|
was_enabled = spu_readch (SPU_RdMachStat) & 0x1;
|
|
spu_idisable ();
|
|
|
|
time = __spu_tb_val + (__spu_tb_timeout - spu_readch (SPU_RdDec));
|
|
|
|
if (__likely (was_enabled))
|
|
spu_ienable ();
|
|
return time;
|
|
}
|