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Coldfire: New timer handling on CPU frequency change, adjusting the prescaler on the fly, for both tick and user timer. Precondition is that the higher frequencies are integer multiples of the base: now NORMAL is 45 MHz and MAX is 124 MHz. Removes the need for applications with longer timer periods (>= 10 ms) to boost the CPU all the time, e.g. the grayscale lib. Timer counts are now always based on the base frequency (CPU_FREQ). * Adjusted the RAM refresh timers to the new frequencies (all frequencies for H100) * All: Fixed the tick timer count being off by one.

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7576 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jens Arnold 2005-10-03 09:24:36 +00:00
parent 7190cf2ed9
commit cfb073c452
10 changed files with 98 additions and 59 deletions
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26
firmware/kernel.c
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@ -156,11 +156,11 @@ int queue_broadcast(long id, void *data)
#if CONFIG_CPU == SH7034
void tick_start(unsigned int interval_in_ms)
{
unsigned int count;
unsigned long count;
count = FREQ * interval_in_ms / 1000 / 8;
count = CPU_FREQ * interval_in_ms / 1000 / 8;
if(count > 0xffff)
if(count > 0x10000)
{
panicf("Error! The tick interval is too long (%d ms)\n",
interval_in_ms);
@ -174,7 +174,7 @@ void tick_start(unsigned int interval_in_ms)
TMDR &= ~0x01; /* Operate normally */
TCNT0 = 0; /* Start counting at 0 */
GRA0 = count;
GRA0 = (unsigned short)(count - 1);
TCR0 = 0x23; /* Clear at GRA match, sysclock/8 */
/* Enable interrupt on level 1 */
@ -186,7 +186,7 @@ void tick_start(unsigned int interval_in_ms)
TSTR |= 0x01; /* Start timer 1 */
}
#pragma interrupt
void IMIA0(void) __attribute__ ((interrupt_handler));
void IMIA0(void)
{
int i;
@ -208,22 +208,28 @@ void IMIA0(void)
#elif defined(CPU_COLDFIRE)
void tick_start(unsigned int interval_in_ms)
{
unsigned int count;
unsigned long count;
int prescale;
count = FREQ/2 * interval_in_ms / 1000 / 16;
count = CPU_FREQ/2 * interval_in_ms / 1000 / 16;
if(count > 0xffff)
if(count > 0x10000)
{
panicf("Error! The tick interval is too long (%d ms)\n",
interval_in_ms);
return;
}
prescale = cpu_frequency / CPU_FREQ;
/* Note: The prescaler is later adjusted on-the-fly on CPU frequency
changes within timer.c */
/* We are using timer 0 */
TRR0 = count; /* The reference count */
TRR0 = (unsigned short)(count - 1); /* The reference count */
TCN0 = 0; /* reset the timer */
TMR0 = 0x001d; /* no prescaler, restart, CLK/16, enabled */
TMR0 = 0x001d | ((unsigned short)(prescale - 1) << 8);
/* restart, CLK/16, enabled, prescaler */
TER0 = 0xff; /* Clear all events */