powerpc: Export PIR data through sysfs

On Fri, Nov 11, 2011 at 10:17:55AM +0530, Ananth N Mavinakayanahalli wrote:
> >
> > At this rate we're going to end up with no bits left for CPU features
> > way too quickly... Especially for something we only care about once at
> > boot time.
> >
> > Wouldn't CPU_FTR_PPCAS_ARCH_V2 be a good enough test ?
>
> /me checks Cell manuals... yes, that test would be good enough. I will
> cook up a patch to use this.

Here it is...
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/kernel/sysfs.c

@@ -177,11 +177,13 @@ SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 SYSFS_PMCSETUP(purr, SPRN_PURR);
 SYSFS_PMCSETUP(spurr, SPRN_SPURR);
 SYSFS_PMCSETUP(dscr, SPRN_DSCR);
+SYSFS_PMCSETUP(pir, SPRN_PIR);
 
 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 static SYSDEV_ATTR(spurr, 0600, show_spurr, NULL);
 static SYSDEV_ATTR(dscr, 0600, show_dscr, store_dscr);
 static SYSDEV_ATTR(purr, 0600, show_purr, store_purr);
+static SYSDEV_ATTR(pir, 0400, show_pir, NULL);
 
 unsigned long dscr_default = 0;
 EXPORT_SYMBOL(dscr_default);
@@ -392,6 +394,9 @@ static void __cpuinit register_cpu_online(unsigned int cpu)
 
 	if (cpu_has_feature(CPU_FTR_DSCR))
 		sysdev_create_file(s, &attr_dscr);
+
+	if (cpu_has_feature(CPU_FTR_PPCAS_ARCH_V2))
+		sysdev_create_file(s, &attr_pir);
 #endif /* CONFIG_PPC64 */
 
 	cacheinfo_cpu_online(cpu);
@@ -462,6 +467,9 @@ static void unregister_cpu_online(unsigned int cpu)
 
 	if (cpu_has_feature(CPU_FTR_DSCR))
 		sysdev_remove_file(s, &attr_dscr);
+
+	if (cpu_has_feature(CPU_FTR_PPCAS_ARCH_V2))
+		sysdev_remove_file(s, &attr_pir);
 #endif /* CONFIG_PPC64 */
 
 	cacheinfo_cpu_offline(cpu);