openkylin
/
qemu
mirror of https://gitee.com/openkylin/qemu.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

Optimize MIPS timer read/write functions 

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4190 c046a42c-6fe2-441c-8c8c-71466251a162
This commit is contained in:
aurel32 2008-04-11 04:55:31 +00:00
parent 1570de2df1
commit ea86e4e600
1 changed files with 31 additions and 37 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

68
hw/mips_timer.c
View File

@ -2,6 +2,8 @@
#include "mips.h"
#include "qemu-timer.h"
#define TIMER_FREQ 100 * 1000 * 1000
void cpu_mips_irqctrl_init (void)
{
}
@ -24,49 +26,41 @@ uint32_t cpu_mips_get_count (CPUState *env)
else
return env->CP0_Count +
(uint32_t)muldiv64(qemu_get_clock(vm_clock),
100 * 1000 * 1000, ticks_per_sec);
TIMER_FREQ, ticks_per_sec);
}
static void cpu_mips_timer_update(CPUState *env)
{
uint64_t now, next;
uint32_t wait;
now = qemu_get_clock(vm_clock);
wait = env->CP0_Compare - env->CP0_Count -
(uint32_t)muldiv64(now, TIMER_FREQ, ticks_per_sec);
next = now + muldiv64(wait, ticks_per_sec, TIMER_FREQ);
qemu_mod_timer(env->timer, next);
}
void cpu_mips_store_count (CPUState *env, uint32_t count)
{
uint64_t now, next;
uint32_t tmp;
uint32_t compare = env->CP0_Compare;
tmp = count;
if (count == compare)
tmp++;
now = qemu_get_clock(vm_clock);
next = now + muldiv64(compare - tmp, ticks_per_sec, 100 * 1000 * 1000);
if (next == now)
next++;
#if 0
if (logfile) {
fprintf(logfile, "%s: 0x%08" PRIx64 " %08x %08x => 0x%08" PRIx64 "\n",
__func__, now, count, compare, next - now);
}
#endif
/* Store new count and compare registers */
env->CP0_Compare = compare;
env->CP0_Count =
count - (uint32_t)muldiv64(now, 100 * 1000 * 1000, ticks_per_sec);
/* Adjust timer */
qemu_mod_timer(env->timer, next);
}
static void cpu_mips_update_count (CPUState *env, uint32_t count)
{
if (env->CP0_Cause & (1 << CP0Ca_DC))
return;
cpu_mips_store_count(env, count);
env->CP0_Count = count;
else {
/* Store new count register */
env->CP0_Count =
count - (uint32_t)muldiv64(qemu_get_clock(vm_clock),
TIMER_FREQ, ticks_per_sec);
/* Update timer timer */
cpu_mips_timer_update(env);
}
}
void cpu_mips_store_compare (CPUState *env, uint32_t value)
{
env->CP0_Compare = value;
cpu_mips_update_count(env, cpu_mips_get_count(env));
if ((env->CP0_Config0 & (0x7 << CP0C0_AR)) == (1 << CP0C0_AR))
if (!(env->CP0_Cause & (1 << CP0Ca_DC)))
cpu_mips_timer_update(env);
if (env->insn_flags & ISA_MIPS32R2)
env->CP0_Cause &= ~(1 << CP0Ca_TI);
qemu_irq_lower(env->irq[(env->CP0_IntCtl >> CP0IntCtl_IPTI) & 0x7]);
}
@ -80,7 +74,7 @@ void cpu_mips_stop_count(CPUState *env)
{
/* Store the current value */
env->CP0_Count += (uint32_t)muldiv64(qemu_get_clock(vm_clock),
100 * 1000 * 1000, ticks_per_sec);
TIMER_FREQ, ticks_per_sec);
}
static void mips_timer_cb (void *opaque)
@ -97,8 +91,8 @@ static void mips_timer_cb (void *opaque)
if (env->CP0_Cause & (1 << CP0Ca_DC))
return;
cpu_mips_update_count(env, cpu_mips_get_count(env));
if ((env->CP0_Config0 & (0x7 << CP0C0_AR)) == (1 << CP0C0_AR))
cpu_mips_timer_update(env);
if (env->insn_flags & ISA_MIPS32R2)
env->CP0_Cause |= 1 << CP0Ca_TI;
qemu_irq_raise(env->irq[(env->CP0_IntCtl >> CP0IntCtl_IPTI) & 0x7]);
}
@ -107,5 +101,5 @@ void cpu_mips_clock_init (CPUState *env)
{
env->timer = qemu_new_timer(vm_clock, &mips_timer_cb, env);
env->CP0_Compare = 0;
cpu_mips_update_count(env, 1);
cpu_mips_store_count(env, 1);
}