[PATCH 03/10] ARM: shmobile: apmu: Add APMU DT support via Enable method


Biju Das <biju.das@...>
 

From: Magnus Damm <damm+renesas@...>

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@...>
[geert: Fix CONFIG_SMP=n build]
Signed-off-by: Geert Uytterhoeven <geert+renesas@...>
Signed-off-by: Simon Horman <horms+renesas@...>

(cherry picked from commit 5f3bca0db8ac01a73622361f6062939638bf4730)
(Backported APMU DT support via Enable method)
Signed-off-by: Biju Das <biju.das@...>
Reviewed-by: Chris Paterson <chris.paterson2@...>

Conflicts:
arch/arm/mach-shmobile/platsmp-apmu.c
---
arch/arm/mach-shmobile/platsmp-apmu.c | 90 ++++++++++++++++++++++++++++++++++-
1 file changed, 89 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-shmobile/platsmp-apmu.c b/arch/arm/mach-shmobile/platsmp-apmu.c
index cff623f..444765e 100644
--- a/arch/arm/mach-shmobile/platsmp-apmu.c
+++ b/arch/arm/mach-shmobile/platsmp-apmu.c
@@ -24,6 +24,7 @@
#include <asm/suspend.h>
#include "common.h"
#include "platsmp-apmu.h"
+#include "rcar-gen2.h"

static struct {
void __iomem *iomem;
@@ -118,12 +119,68 @@ static void apmu_parse_cfg(void (*fn)(struct resource *res, int cpu, int bit),
}
}

+static const struct of_device_id apmu_ids[] = {
+ { .compatible = "renesas,apmu" },
+ { /*sentinel*/ }
+};
+
+static void apmu_parse_dt(void (*fn)(struct resource *res, int cpu, int bit))
+{
+ struct device_node *np_apmu, *np_cpu;
+ struct resource res;
+ int bit, index;
+ u32 id;
+
+ for_each_matching_node(np_apmu, apmu_ids) {
+ /* only enable the cluster that includes the boot CPU */
+ bool is_allowed = false;
+
+ for (bit = 0; bit < CONFIG_NR_CPUS; bit++) {
+ np_cpu = of_parse_phandle(np_apmu, "cpus", bit);
+ if (np_cpu) {
+ if (!of_property_read_u32(np_cpu, "reg", &id)) {
+ if (id == cpu_logical_map(0)) {
+ is_allowed = true;
+ of_node_put(np_cpu);
+ break;
+ }
+
+ }
+ of_node_put(np_cpu);
+ }
+ }
+ if (!is_allowed)
+ continue;
+
+ for (bit = 0; bit < CONFIG_NR_CPUS; bit++) {
+ np_cpu = of_parse_phandle(np_apmu, "cpus", bit);
+ if (np_cpu) {
+ if (!of_property_read_u32(np_cpu, "reg", &id)) {
+ index = get_logical_index(id);
+ if ((index >= 0) &&
+ !of_address_to_resource(np_apmu,
+ 0, &res))
+ fn(&res, index, bit);
+ }
+ of_node_put(np_cpu);
+ }
+ }
+ }
+}
+
+static void __init shmobile_smp_apmu_setup_boot(void)
+{
+ /* install boot code shared by all CPUs */
+ shmobile_boot_fn = virt_to_phys(shmobile_smp_boot);
+ shmobile_boot_arg = MPIDR_HWID_BITMASK;
+}
+
void __init shmobile_smp_apmu_prepare_cpus(unsigned int max_cpus,
struct rcar_apmu_config *apmu_config,
int num)
{
/* install boot code shared by all CPUs */
- shmobile_boot_fn = virt_to_phys(shmobile_smp_boot);
+ shmobile_smp_apmu_setup_boot();
shmobile_boot_arg = MPIDR_HWID_BITMASK;

/* perform per-cpu setup */
@@ -137,7 +194,38 @@ int shmobile_smp_apmu_boot_secondary(unsigned int cpu, struct task_struct *idle)

return apmu_wrap(cpu, apmu_power_on);
}
+
+static void __init shmobile_smp_apmu_prepare_cpus_dt(unsigned int max_cpus)
+{
+ shmobile_smp_apmu_setup_boot();
+ apmu_parse_dt(apmu_init_cpu);
+ rcar_gen2_pm_init();
+}
+
+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
+};
+
+CPU_METHOD_OF_DECLARE(shmobile_smp_apmu, "renesas,apmu", &apmu_smp_ops);
+#endif /* CONFIG_SMP */

#if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_SUSPEND)
/* nicked from arch/arm/mach-exynos/hotplug.c */
--
2.7.4