arm: mvebu: Add initial support for power managmement service unit

The Armada 370 and Armada XP SOCs have a power management service unit
which is responsible for powering down and waking up CPUs and other
SOC units. This patch adds support for this unit.

Signed-off-by: Yehuda Yitschak <yehuday@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

1 files changed, 75 insertions, 0 deletions

diff --git a/arch/arm/mach-mvebu/pmsu.c b/arch/arm/mach-mvebu/pmsu.c
new file mode 100644
index 00000000000..3cc4bef6401
--- /dev/null
+++ b/arch/arm/mach-mvebu/pmsu.c
@@ -0,0 +1,75 @@
+/*
+ * Power Management Service Unit(PMSU) support for Armada 370/XP platforms.
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Yehuda Yitschak <yehuday@marvell.com>
+ * Gregory Clement <gregory.clement@free-electrons.com>
+ * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * The Armada 370 and Armada XP SOCs have a power management service
+ * unit which is responsible for powering down and waking up CPUs and
+ * other SOC units
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+#include <linux/smp.h>
+#include <asm/smp_plat.h>
+
+static void __iomem *pmsu_mp_base;
+static void __iomem *pmsu_reset_base;
+
+#define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu)	((cpu * 0x100) + 0x24)
+#define PMSU_RESET_CTL_OFFSET(cpu)		(cpu * 0x8)
+
+static struct of_device_id of_pmsu_table[] = {
+	{.compatible = "marvell,armada-370-xp-pmsu"},
+	{ /* end of list */ },
+};
+
+#ifdef CONFIG_SMP
+int armada_xp_boot_cpu(unsigned int cpu_id, void *boot_addr)
+{
+	int reg, hw_cpu;
+
+	if (!pmsu_mp_base || !pmsu_reset_base) {
+		pr_warn("Can't boot CPU. PMSU is uninitialized\n");
+		return 1;
+	}
+
+	hw_cpu = cpu_logical_map(cpu_id);
+
+	writel(virt_to_phys(boot_addr), pmsu_mp_base +
+			PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
+
+	/* Release CPU from reset by clearing reset bit*/
+	reg = readl(pmsu_reset_base + PMSU_RESET_CTL_OFFSET(hw_cpu));
+	reg &= (~0x1);
+	writel(reg, pmsu_reset_base + PMSU_RESET_CTL_OFFSET(hw_cpu));
+
+	return 0;
+}
+#endif
+
+int __init armada_370_xp_pmsu_init(void)
+{
+	struct device_node *np;
+
+	np = of_find_matching_node(NULL, of_pmsu_table);
+	if (np) {
+		pr_info("Initializing Power Management Service Unit\n");
+		pmsu_mp_base = of_iomap(np, 0);
+		pmsu_reset_base = of_iomap(np, 1);
+	}
+
+	return 0;
+}
+
+early_initcall(armada_370_xp_pmsu_init);