On 06/16/2016 01:27 PM, Geert Uytterhoeven wrote:
From: Magnus Damm <[email protected]>
Allow DT configuration of the APMU hardware in the case when the APMU is
pointed out in the DTB via the enable-method. The ability to configure
the APMU via C code is still kept intact to prevent DTB breakage for older
SoCs that do not rely on the enable-method for SMP support.
Signed-off-by: Magnus Damm <[email protected]>
[geert: Fix CONFIG_SMP=n build]
Signed-off-by: Geert Uytterhoeven <[email protected]>
[...]
diff --git a/arch/arm/mach-shmobile/platsmp-apmu.c
b/arch/arm/mach-shmobile/platsmp-apmu.c
index c1558ef0c590dd3e..0c6bb458b7a45128 100644
--- a/arch/arm/mach-shmobile/platsmp-apmu.c
+++ b/arch/arm/mach-shmobile/platsmp-apmu.c
[...]
+static int shmobile_smp_apmu_boot_secondary_md21(unsigned int cpu,
+ struct task_struct *idle)
+{
+ /* Error out when hardware debug mode is enabled */
+ if (rcar_gen2_read_mode_pins() & BIT(21)) {
+ pr_warn("Unable to boot CPU%u when MD21 is set\n", cpu);
+ return -ENOTSUPP;
+ }
+
+ return shmobile_smp_apmu_boot_secondary(cpu, idle);
+}
+
+static struct smp_operations apmu_smp_ops __initdata = {
+ .smp_prepare_cpus = shmobile_smp_apmu_prepare_cpus_dt,
+ .smp_boot_secondary = shmobile_smp_apmu_boot_secondary_md21,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_can_disable = shmobile_smp_cpu_can_disable,
+ .cpu_die = shmobile_smp_apmu_cpu_die,
+ .cpu_kill = shmobile_smp_apmu_cpu_kill,
#endif
For the record: it turned out that I tested my non-DT SMP on
R8A7792/Blanche with MD21 bit set. And I've just made sure it still works with
this implementation (by commenting out the check above.
Also, I was going to try the workaround for MD21 I saw in the BSP tree --
perhaps it'll help get R8A7791 working w/MD21 set...
MBR, Sergei
