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[CELL] cbe_cpufreq: fix latency measurement

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This patch fixes the debug code that calculates the transition time when
changing the slow modes on a Cell BE cpu.

Signed-off-by: Christian Krafft <krafft@de.ibm.com>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
This commit is contained in:
Christian Krafft
2007-07-20 21:39:19 +02:00
committed by Arnd Bergmann
parent 813f90728e
commit a964b9be3e
1 changed files with 17 additions and 8 deletions
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25
arch/powerpc/platforms/cell/cbe_cpufreq.c
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@@ -81,7 +81,7 @@ static int set_pmode_pmi(int cpu, unsigned int pmode)
int ret; int ret;
pmi_message_t pmi_msg; pmi_message_t pmi_msg;
#ifdef DEBUG #ifdef DEBUG
u64 time; long time;
#endif #endif
pmi_msg.type = PMI_TYPE_FREQ_CHANGE; pmi_msg.type = PMI_TYPE_FREQ_CHANGE;
@@ -89,7 +89,7 @@ static int set_pmode_pmi(int cpu, unsigned int pmode)
pmi_msg.data2 = pmode; pmi_msg.data2 = pmode;
#ifdef DEBUG #ifdef DEBUG
time = (u64) get_cycles(); time = jiffies;
#endif #endif
pmi_send_message(pmi_msg); pmi_send_message(pmi_msg);
@@ -98,9 +98,9 @@ static int set_pmode_pmi(int cpu, unsigned int pmode)
pr_debug("PMI returned slow mode %d\n", ret); pr_debug("PMI returned slow mode %d\n", ret);
#ifdef DEBUG #ifdef DEBUG
time = (u64) get_cycles() - time; /* actual cycles (not cpu cycles!) */ time = jiffies - time; /* actual cycles (not cpu cycles!) */
time = 1000000000 * time / CLOCK_TICK_RATE; /* time in ns (10^-9) */ time = jiffies_to_msecs(time);
pr_debug("had to wait %lu ns for a transition\n", time); pr_debug("had to wait %lu ms for a transition using PMI.\n", time);
#endif #endif
return ret; return ret;
} }
@@ -123,15 +123,18 @@ static int set_pmode_reg(int cpu, unsigned int pmode)
struct cbe_mic_tm_regs __iomem *mic_tm_regs; struct cbe_mic_tm_regs __iomem *mic_tm_regs;
u64 flags; u64 flags;
u64 value; u64 value;
#ifdef DEBUG
long time;
#endif
local_irq_save(flags); local_irq_save(flags);
mic_tm_regs = cbe_get_cpu_mic_tm_regs(cpu); mic_tm_regs = cbe_get_cpu_mic_tm_regs(cpu);
pmd_regs = cbe_get_cpu_pmd_regs(cpu); pmd_regs = cbe_get_cpu_pmd_regs(cpu);
pr_debug("pm register is mapped at %p\n", &pmd_regs->pmcr); #ifdef DEBUG
pr_debug("mic register is mapped at %p\n", &mic_tm_regs->slow_fast_timer_0); time = jiffies;
#endif
out_be64(&mic_tm_regs->slow_fast_timer_0, MIC_Slow_Fast_Timer_table[pmode]); out_be64(&mic_tm_regs->slow_fast_timer_0, MIC_Slow_Fast_Timer_table[pmode]);
out_be64(&mic_tm_regs->slow_fast_timer_1, MIC_Slow_Fast_Timer_table[pmode]); out_be64(&mic_tm_regs->slow_fast_timer_1, MIC_Slow_Fast_Timer_table[pmode]);
@@ -146,6 +149,7 @@ static int set_pmode_reg(int cpu, unsigned int pmode)
out_be64(&pmd_regs->pmcr, value); out_be64(&pmd_regs->pmcr, value);
#ifdef DEBUG
/* wait until new pmode appears in status register */ /* wait until new pmode appears in status register */
value = in_be64(&pmd_regs->pmsr) & 0x07; value = in_be64(&pmd_regs->pmsr) & 0x07;
while(value != pmode) { while(value != pmode) {
@@ -153,6 +157,11 @@ static int set_pmode_reg(int cpu, unsigned int pmode)
value = in_be64(&pmd_regs->pmsr) & 0x07; value = in_be64(&pmd_regs->pmsr) & 0x07;
} }
time = jiffies - time;
time = jiffies_to_msecs(time);
pr_debug("had to wait %lu ms for a transition using " \
"the pervasive unit.\n", time);
#endif
local_irq_restore(flags); local_irq_restore(flags);
return 0; return 0;