[CELL] cbe_cpufreq: fix latency measurement

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>

1 files changed, 17 insertions, 8 deletions

diff --git a/arch/powerpc/platforms/cell/cbe_cpufreq.c b/arch/powerpc/platforms/cell/cbe_cpufreq.c
index 3586f5290490..5820fb9a4521 100644
--- a/arch/powerpc/platforms/cell/cbe_cpufreq.c
+++ b/arch/powerpc/platforms/cell/cbe_cpufreq.c
@@ -81,7 +81,7 @@ static int set_pmode_pmi(int cpu, unsigned int pmode)
         int ret;
         pmi_message_t pmi_msg;
 #ifdef DEBUG
-        u64 time;
+        long time;
 #endif
 
         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;
 
 #ifdef DEBUG
-        time = (u64) get_cycles();
+        time = jiffies;
 #endif
 
         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);
 
 #ifdef DEBUG
-        time = (u64) get_cycles() - time; /* actual cycles (not cpu cycles!) */
-        time = 1000000000 * time / CLOCK_TICK_RATE; /* time in ns (10^-9) */
-        pr_debug("had to wait %lu ns for a transition\n", time);
+        time = jiffies - time; /* actual cycles (not cpu cycles!) */
+        time = jiffies_to_msecs(time);
+        pr_debug("had to wait %lu ms for a transition using PMI.\n", time);
 #endif
         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;
         u64 flags;
         u64 value;
+#ifdef DEBUG
+        long time;
+#endif
 
         local_irq_save(flags);
 
         mic_tm_regs = cbe_get_cpu_mic_tm_regs(cpu);
         pmd_regs = cbe_get_cpu_pmd_regs(cpu);
 
-        pr_debug("pm register is mapped at %p\n", &pmd_regs->pmcr);
-        pr_debug("mic register is mapped at %p\n", &mic_tm_regs->slow_fast_timer_0);
-
+#ifdef DEBUG
+        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_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);
 
+#ifdef DEBUG
         /* wait until new pmode appears in status register */
         value = in_be64(&pmd_regs->pmsr) & 0x07;
         while(value != pmode) {
@@ -153,6 +157,11 @@ static int set_pmode_reg(int cpu, unsigned int pmode)
                 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);
 
         return 0;