[PATCHv5 2/5] arm: mvebu: support for SMP on 98DX3336 SoC

From: Chris Packham
Date: Thu Jan 26 2017 - 22:26:48 EST


Compared to the armada-xp the 98DX3336 uses different registers to set
the boot address for the secondary CPU so a new enable-method is needed.
This will only work if the machine definition doesn't define an overall
smp_ops because there is not currently a way of overriding this from the
device tree if it is set in the machine definition.

Signed-off-by: Chris Packham <chris.packham@xxxxxxxxxxxxxxxxxxx>
Acked-by: Rob Herring <robh@xxxxxxxxxx>
---

Notes:
Changes in v2:
- Document new enable-method value
- Correct some references from 98DX4521 to 98DX3236
Changes in v3:
- Simplify mv98dx3236_resume_init by using of_io_request_and_map()
Changes in v4:
- integrate changes into platsmp.c instead of new init call
- avoid duplicated code.
- fix error return
- Collect ack from Rob
Changes in v5:
- Remove useless casts (thanks to Stephen Boyd)

Documentation/devicetree/bindings/arm/cpus.txt | 1 +
.../bindings/arm/marvell/98dx3236-resume-ctrl.txt | 16 ++++
arch/arm/mach-mvebu/platsmp.c | 86 ++++++++++++++++++++++
3 files changed, 103 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/marvell/98dx3236-resume-ctrl.txt

diff --git a/Documentation/devicetree/bindings/arm/cpus.txt b/Documentation/devicetree/bindings/arm/cpus.txt
index a1bcfeed5f24..3c2fd72d0bf9 100644
--- a/Documentation/devicetree/bindings/arm/cpus.txt
+++ b/Documentation/devicetree/bindings/arm/cpus.txt
@@ -202,6 +202,7 @@ nodes to be present and contain the properties described below.
"marvell,armada-380-smp"
"marvell,armada-390-smp"
"marvell,armada-xp-smp"
+ "marvell,98dx3236-smp"
"mediatek,mt6589-smp"
"mediatek,mt81xx-tz-smp"
"qcom,gcc-msm8660"
diff --git a/Documentation/devicetree/bindings/arm/marvell/98dx3236-resume-ctrl.txt b/Documentation/devicetree/bindings/arm/marvell/98dx3236-resume-ctrl.txt
new file mode 100644
index 000000000000..26eb9d3aa630
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/marvell/98dx3236-resume-ctrl.txt
@@ -0,0 +1,16 @@
+Resume Control
+--------------
+Available on Marvell SOCs: 98DX3336 and 98DX4251
+
+Required properties:
+
+- compatible: must be "marvell,98dx3336-resume-ctrl"
+
+- reg: Should contain resume control registers location and length
+
+Example:
+
+resume@20980 {
+ compatible = "marvell,98dx3336-resume-ctrl";
+ reg = <0x20980 0x10>;
+};
diff --git a/arch/arm/mach-mvebu/platsmp.c b/arch/arm/mach-mvebu/platsmp.c
index 46c742d3bd41..a5b464497e1a 100644
--- a/arch/arm/mach-mvebu/platsmp.c
+++ b/arch/arm/mach-mvebu/platsmp.c
@@ -184,3 +184,89 @@ const struct smp_operations armada_xp_smp_ops __initconst = {

CPU_METHOD_OF_DECLARE(armada_xp_smp, "marvell,armada-xp-smp",
&armada_xp_smp_ops);
+
+struct resume_controller {
+ u32 resume_control;
+ u32 resume_boot_addr;
+};
+
+static const struct resume_controller mv98dx3336_resume_controller = {
+ .resume_control = 0x08,
+ .resume_boot_addr = 0x04,
+};
+
+static const struct of_device_id of_mv98dx3236_resume_table[] = {
+ {
+ .compatible = "marvell,98dx3336-resume-ctrl",
+ .data = &mv98dx3336_resume_controller,
+ },
+ { /* end of list */ },
+};
+
+static int mv98dx3236_resume_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
+{
+ const struct of_device_id *match;
+ struct device_node *np;
+ void __iomem *base;
+ const struct resume_controller *rc;
+
+ WARN_ON(hw_cpu != 1);
+
+ np = of_find_matching_node_and_match(NULL, of_mv98dx3236_resume_table,
+ &match);
+ if (!np)
+ return -ENODEV;
+
+ base = of_io_request_and_map(np, 0, of_node_full_name(np));
+ rc = match->data;
+ of_node_put(np);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ writel(0, base + rc->resume_control);
+ writel(virt_to_phys(boot_addr), base + rc->resume_boot_addr);
+
+ return 0;
+}
+
+static int mv98dx3236_boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ int ret, hw_cpu;
+
+ hw_cpu = cpu_logical_map(cpu);
+ set_secondary_cpu_clock(hw_cpu);
+ mv98dx3236_resume_set_cpu_boot_addr(hw_cpu,
+ armada_xp_secondary_startup);
+
+ /*
+ * This is needed to wake up CPUs in the offline state after
+ * using CPU hotplug.
+ */
+ arch_send_wakeup_ipi_mask(cpumask_of(cpu));
+
+ /*
+ * This is needed to take secondary CPUs out of reset on the
+ * initial boot.
+ */
+ ret = mvebu_cpu_reset_deassert(hw_cpu);
+ if (ret) {
+ pr_warn("unable to boot CPU: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct smp_operations mv98dx3236_smp_ops __initconst = {
+ .smp_init_cpus = armada_xp_smp_init_cpus,
+ .smp_prepare_cpus = armada_xp_smp_prepare_cpus,
+ .smp_boot_secondary = mv98dx3236_boot_secondary,
+ .smp_secondary_init = armada_xp_secondary_init,
+#ifdef CONFIG_HOTPLUG_CPU
+ .cpu_die = armada_xp_cpu_die,
+ .cpu_kill = armada_xp_cpu_kill,
+#endif
+};
+
+CPU_METHOD_OF_DECLARE(mv98dx3236_smp, "marvell,98dx3236-smp",
+ &mv98dx3236_smp_ops);
--
2.11.0.24.ge6920cf