[PATCH 3.14 62/77] Revert "ARM: 7830/1: delay: dont bother reporting bogomips in /proc/cpuinfo"

Greg Kroah-Hartman
2015-01-14T07:56:47Z

From: Pavel Machek <pavel@ucw.cz>

commit 4bf9636c39ac70da091d5a2e28d3448eaa7f115c upstream.

Commit 9fc2105aeaaf ("ARM: 7830/1: delay: don't bother reporting
bogomips in /proc/cpuinfo") breaks audio in python, and probably
elsewhere, with message

FATAL: cannot locate cpu MHz in /proc/cpuinfo

I'm not the first one to hit it, see for example

https://theredblacktree.wordpress.com/2014/08/10/fatal-cannot-locate-cpu-mhz-in-proccpuinfo/
https://devtalk.nvidia.com/default/topic/765800/workaround-for-fatal-cannot-locate-cpu-mhz-in-proc-cpuinf/?offset=1

Reading original changelog, I have to say "Stop breaking working setups.
You know who you are!".

Signed-off-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/arm/kernel/setup.c | 9 +++++++++
arch/arm/kernel/smp.c | 13 +++++++++++--
2 files changed, 20 insertions(+), 2 deletions(-)

--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -1021,6 +1021,15 @@ static int c_show(struct seq_file *m, vo
seq_printf(m, "model name\t: %s rev %d (%s)\n",
cpu_name, cpuid & 15, elf_platform);

+#if defined(CONFIG_SMP)
+ seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
+ per_cpu(cpu_data, i).loops_per_jiffy / (500000UL/HZ),
+ (per_cpu(cpu_data, i).loops_per_jiffy / (5000UL/HZ)) % 100);
+#else
+ seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
+ loops_per_jiffy / (500000/HZ),
+ (loops_per_jiffy / (5000/HZ)) % 100);
+#endif
/* dump out the processor features */
seq_puts(m, "Features\t: ");

--- a/arch/arm/kernel/smp.c
+++ b/arch/arm/kernel/smp.c
@@ -388,8 +388,17 @@ asmlinkage void secondary_start_kernel(v

void __init smp_cpus_done(unsigned int max_cpus)
{
- printk(KERN_INFO "SMP: Total of %d processors activated.\n",
- num_online_cpus());
+ int cpu;
+ unsigned long bogosum = 0;
+
+ for_each_online_cpu(cpu)
+ bogosum += per_cpu(cpu_data, cpu).loops_per_jiffy;
+
+ printk(KERN_INFO "SMP: Total of %d processors activated "
+ "(%lu.%02lu BogoMIPS).\n",
+ num_online_cpus(),
+ bogosum / (500000/HZ),
+ (bogosum / (5000/HZ)) % 100);

hyp_mode_check();
}