Hello.
On 06/24/2016 10:44 AM, Geert Uytterhoeven wrote:
From: Magnus Damm <damm+renesas@xxxxxxxxxxxxx>
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 <damm+renesas@xxxxxxxxxxxxx>
[geert: Fix CONFIG_SMP=n build]
Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
[...]
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 --
Which workaround? I only saw the BSP removed the check, but it didn't mention
why (because E2 and V2H don't need it, or...?).
I'm looking at the <soc>_smp_prepare_cpus() in
arch/arm/mach-shmobile/setup-<soc>.c in the
'bsp/v3.10.31-ltsi/rcar-gen2-1.9.6' branch of Simon's renesas-backport.git.
The all have the code to handle MD21 bit set (by setting some bits in
CA{7,15}DBGRCR.
perhaps it'll help get R8A7791 working w/MD21 set...
Does your Porter work with the other MD21 setting (and the check commented
out, of coutse)?
Yes, I've made sure it works now.
Gr{oetje,eeting}s,
Geert
MBR, Sergei
