ARM: msm: platsmp: determine number of CPU cores at boot time
Previously we just assumed there were CONFIG_NR_CPUS cpus present in
the system. Instead, figure out the number of cpus from the MIDR
register.
Signed-off-by: Jeff Ohlstein <johlstei@codeaurora.org>
Signed-off-by: David Brown <davidb@codeaurora.org>
[arnd: clarified patch title]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/arm/mach-msm/platsmp.c b/arch/arm/mach-msm/platsmp.c
index 2034098..5ba77d0 100644
--- a/arch/arm/mach-msm/platsmp.c
+++ b/arch/arm/mach-msm/platsmp.c
@@ -18,6 +18,7 @@
#include <asm/hardware/gic.h>
#include <asm/cacheflush.h>
+#include <asm/cputype.h>
#include <asm/mach-types.h>
#include <mach/msm_iomap.h>
@@ -40,6 +41,12 @@
static DEFINE_SPINLOCK(boot_lock);
+static inline int get_core_count(void)
+{
+ /* 1 + the PART[1:0] field of MIDR */
+ return ((read_cpuid_id() >> 4) & 3) + 1;
+}
+
void __cpuinit platform_secondary_init(unsigned int cpu)
{
/* Configure edge-triggered PPIs */
@@ -147,9 +154,9 @@
*/
void __init smp_init_cpus(void)
{
- unsigned int i;
+ unsigned int i, ncores = get_core_count();
- for (i = 0; i < NR_CPUS; i++)
+ for (i = 0; i < ncores; i++)
set_cpu_possible(i, true);
set_smp_cross_call(gic_raise_softirq);