[PATCH 02/02] ARM: shmobile: Per-CPU SMP boot / sleep code for SCU SoCs

Magnus Damm magnus.damm at gmail.com
Wed Jul 31 14:38:27 EDT 2013


From: Magnus Damm <damm at opensource.se>

Hook in the per-CPU boot and sleep code in the shared
mach-shmobile SCU code. CPUs may be kept in the asm
routine until ->boot_secondary() when the per-CPU
boot vector is installed. At the end of ->die() the
asm sleep routine is invoked.

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

 arch/arm/mach-shmobile/platsmp-scu.c |   17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

--- 0006/arch/arm/mach-shmobile/platsmp-scu.c
+++ work/arch/arm/mach-shmobile/platsmp-scu.c	2013-07-31 12:18:32.000000000 +0900
@@ -18,8 +18,9 @@
 
 void __init shmobile_smp_scu_prepare_cpus(unsigned int max_cpus)
 {
-	shmobile_boot_fn = virt_to_phys(shmobile_boot_scu);
-	shmobile_boot_arg = (unsigned long)shmobile_scu_base;
+	/* install boot code shared by all CPUs */
+	shmobile_boot_fn = virt_to_phys(shmobile_smp_boot);
+	shmobile_boot_arg = MPIDR_HWID_BITMASK;
 
 	/* enable SCU and cache coherency on booting CPU */
 	scu_enable(shmobile_scu_base);
@@ -28,22 +29,26 @@ void __init shmobile_smp_scu_prepare_cpu
 
 int shmobile_smp_scu_boot_secondary(unsigned int cpu, struct task_struct *idle)
 {
-	/* do nothing for now */
+	/* For this particular CPU register SCU boot vector */
+	shmobile_smp_hook(cpu, virt_to_phys(shmobile_boot_scu),
+			  (unsigned long)shmobile_scu_base);
 	return 0;
 }
 
 #ifdef CONFIG_HOTPLUG_CPU
 void shmobile_smp_scu_cpu_die(unsigned int cpu)
 {
+	/* For this particular CPU deregister boot vector */
+	shmobile_smp_hook(cpu, 0, 0);
+
 	dsb();
 	flush_cache_all();
 
 	/* disable cache coherency */
 	scu_power_mode(shmobile_scu_base, SCU_PM_POWEROFF);
 
-	/* Endless loop until reset */
-	while (1)
-		cpu_do_idle();
+	/* jump to shared mach-shmobile sleep / reset code */
+	shmobile_smp_sleep();
 }
 
 static int shmobile_smp_scu_psr_core_disabled(int cpu)



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