[PATCH] msm: platsmp: actually read core count in get_core_count

From: Jeff Ohlstein
Date: Thu Apr 07 2011 - 20:41:36 EST


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@xxxxxxxxxxxxxx>
---
arch/arm/mach-msm/platsmp.c | 11 +++++++++--
1 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-msm/platsmp.c b/arch/arm/mach-msm/platsmp.c
index 0f427bc..58c1d7b 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 @@ volatile int pen_release = -1;

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 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
*/
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);
}

--
Sent by an employee of the Qualcomm Innovation Center, Inc.
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum.

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