[PATCH 01/05] ARM: shmobile: Add CPU notifier based SCU boot vector code

Magnus Damm magnus.damm at gmail.com
Sat Sep 14 09:46:25 EDT 2013


From: Magnus Damm <damm at opensource.se>

Add CPU notifiers for the shared mach-shmobile SCU code
to allow removal of the shared SCU boot_secondary code.

Regarding notifiers, at CPU_UP_PREPARE time the SMP boot
vector is initialized so secondary CPU cores can boot.

Signed-off-by: Magnus Damm <damm at opensource.se>
---

 arch/arm/mach-shmobile/platsmp-scu.c |   24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

--- 0001/arch/arm/mach-shmobile/platsmp-scu.c
+++ work/arch/arm/mach-shmobile/platsmp-scu.c	2013-09-14 22:15:07.000000000 +0900
@@ -7,6 +7,7 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
+#include <linux/cpu.h>
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/io.h>
@@ -16,6 +17,26 @@
 #include <asm/smp_scu.h>
 #include <mach/common.h>
 
+static int shmobile_smp_scu_notifier_call(struct notifier_block *nfb,
+					  unsigned long action, void *hcpu)
+{
+	unsigned int cpu = (long)hcpu;
+
+	switch (action) {
+	case CPU_UP_PREPARE:
+		/* For this particular CPU register SCU SMP boot vector */
+		shmobile_smp_hook(cpu, virt_to_phys(shmobile_boot_scu),
+				  (unsigned long)shmobile_scu_base);
+		break;
+	};
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block shmobile_smp_scu_notifier = {
+	.notifier_call = shmobile_smp_scu_notifier_call,
+};
+
 void __init shmobile_smp_scu_prepare_cpus(unsigned int max_cpus)
 {
 	/* install boot code shared by all CPUs */
@@ -25,6 +46,9 @@ void __init shmobile_smp_scu_prepare_cpu
 	/* enable SCU and cache coherency on booting CPU */
 	scu_enable(shmobile_scu_base);
 	scu_power_mode(shmobile_scu_base, SCU_PM_NORMAL);
+
+	/* Use CPU notifier for reset vector control */
+	register_cpu_notifier(&shmobile_smp_scu_notifier);
 }
 
 int shmobile_smp_scu_boot_secondary(unsigned int cpu, struct task_struct *idle)



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