alpha: Allow HZ to be configured

With the 1024Hz default, we spend 50% of QEMU emulation
processing timer interrupts.

Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 8 insertions, 2 deletions

diff --git a/arch/alpha/kernel/setup.c b/arch/alpha/kernel/setup.c
index c38d6a1b9066..b20af76f12c1 100644
--- a/arch/alpha/kernel/setup.c
+++ b/arch/alpha/kernel/setup.c
@@ -1218,6 +1218,7 @@ show_cpuinfo(struct seq_file *f, void *slot)
         char *systype_name;
         char *sysvariation_name;
         int nr_processors;
+        unsigned long timer_freq;
 
         cpu_index = (unsigned) (cpu->type - 1);
         cpu_name = "Unknown";
@@ -1229,6 +1230,12 @@ show_cpuinfo(struct seq_file *f, void *slot)
 
         nr_processors = get_nr_processors(cpu, hwrpb->nr_processors);
 
+#if CONFIG_HZ == 1024 || CONFIG_HZ == 1200
+        timer_freq = (100UL * hwrpb->intr_freq) / 4096;
+#else
+        timer_freq = 100UL * CONFIG_HZ;
+#endif
+
         seq_printf(f, "cpu\t\t\t: Alpha\n"
                       "cpu model\t\t: %s\n"
                       "cpu variation\t\t: %ld\n"
@@ -1254,8 +1261,7 @@ show_cpuinfo(struct seq_file *f, void *slot)
                        (char*)hwrpb->ssn,
                        est_cycle_freq ? : hwrpb->cycle_freq,
                        est_cycle_freq ? "est." : "",
-                       hwrpb->intr_freq / 4096,
-                       (100 * hwrpb->intr_freq / 4096) % 100,
+                       timer_freq / 100, timer_freq % 100,
                        hwrpb->pagesize,
                        hwrpb->pa_bits,
                        hwrpb->max_asn,