1 files changed, 293 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..25aa8237d66
--- /dev/null
+++ b/arch/arm/mach-mvebu/pmsu.c
@@ -0,0 +1,293 @@
+/*
+ * 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
+ */
+
+#define pr_fmt(fmt) "mvebu-pmsu: " fmt
+
+#include <linux/cpu_pm.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/smp.h>
+#include <linux/resource.h>
+#include <asm/cacheflush.h>
+#include <asm/cp15.h>
+#include <asm/smp_plat.h>
+#include <asm/suspend.h>
+#include <asm/tlbflush.h>
+#include "common.h"
+
+static void __iomem *pmsu_mp_base;
+
+#define PMSU_BASE_OFFSET    0x100
+#define PMSU_REG_SIZE	    0x1000
+
+/* PMSU MP registers */
+#define PMSU_CONTROL_AND_CONFIG(cpu)	    ((cpu * 0x100) + 0x104)
+#define PMSU_CONTROL_AND_CONFIG_DFS_REQ		BIT(18)
+#define PMSU_CONTROL_AND_CONFIG_PWDDN_REQ	BIT(16)
+#define PMSU_CONTROL_AND_CONFIG_L2_PWDDN	BIT(20)
+
+#define PMSU_CPU_POWER_DOWN_CONTROL(cpu)    ((cpu * 0x100) + 0x108)
+
+#define PMSU_CPU_POWER_DOWN_DIS_SNP_Q_SKIP	BIT(0)
+
+#define PMSU_STATUS_AND_MASK(cpu)	    ((cpu * 0x100) + 0x10c)
+#define PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT	BIT(16)
+#define PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT	BIT(17)
+#define PMSU_STATUS_AND_MASK_IRQ_WAKEUP		BIT(20)
+#define PMSU_STATUS_AND_MASK_FIQ_WAKEUP		BIT(21)
+#define PMSU_STATUS_AND_MASK_DBG_WAKEUP		BIT(22)
+#define PMSU_STATUS_AND_MASK_IRQ_MASK		BIT(24)
+#define PMSU_STATUS_AND_MASK_FIQ_MASK		BIT(25)
+
+#define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x124)
+
+/* PMSU fabric registers */
+#define L2C_NFABRIC_PM_CTL		    0x4
+#define L2C_NFABRIC_PM_CTL_PWR_DOWN		BIT(20)
+
+extern void ll_disable_coherency(void);
+extern void ll_enable_coherency(void);
+
+extern void armada_370_xp_cpu_resume(void);
+
+static struct platform_device armada_xp_cpuidle_device = {
+	.name = "cpuidle-armada-370-xp",
+};
+
+static struct of_device_id of_pmsu_table[] = {
+	{ .compatible = "marvell,armada-370-pmsu", },
+	{ .compatible = "marvell,armada-370-xp-pmsu", },
+	{ .compatible = "marvell,armada-380-pmsu", },
+	{ /* end of list */ },
+};
+
+void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
+{
+	writel(virt_to_phys(boot_addr), pmsu_mp_base +
+		PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
+}
+
+static int __init armada_370_xp_pmsu_init(void)
+{
+	struct device_node *np;
+	struct resource res;
+	int ret = 0;
+
+	np = of_find_matching_node(NULL, of_pmsu_table);
+	if (!np)
+		return 0;
+
+	pr_info("Initializing Power Management Service Unit\n");
+
+	if (of_address_to_resource(np, 0, &res)) {
+		pr_err("unable to get resource\n");
+		ret = -ENOENT;
+		goto out;
+	}
+
+	if (of_device_is_compatible(np, "marvell,armada-370-xp-pmsu")) {
+		pr_warn(FW_WARN "deprecated pmsu binding\n");
+		res.start = res.start - PMSU_BASE_OFFSET;
+		res.end = res.start + PMSU_REG_SIZE - 1;
+	}
+
+	if (!request_mem_region(res.start, resource_size(&res),
+				np->full_name)) {
+		pr_err("unable to request region\n");
+		ret = -EBUSY;
+		goto out;
+	}
+
+	pmsu_mp_base = ioremap(res.start, resource_size(&res));
+	if (!pmsu_mp_base) {
+		pr_err("unable to map registers\n");
+		release_mem_region(res.start, resource_size(&res));
+		ret = -ENOMEM;
+		goto out;
+	}
+
+ out:
+	of_node_put(np);
+	return ret;
+}
+
+static void armada_370_xp_pmsu_enable_l2_powerdown_onidle(void)
+{
+	u32 reg;
+
+	if (pmsu_mp_base == NULL)
+		return;
+
+	/* Enable L2 & Fabric powerdown in Deep-Idle mode - Fabric */
+	reg = readl(pmsu_mp_base + L2C_NFABRIC_PM_CTL);
+	reg |= L2C_NFABRIC_PM_CTL_PWR_DOWN;
+	writel(reg, pmsu_mp_base + L2C_NFABRIC_PM_CTL);
+}
+
+/* No locking is needed because we only access per-CPU registers */
+void armada_370_xp_pmsu_idle_prepare(bool deepidle)
+{
+	unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
+	u32 reg;
+
+	if (pmsu_mp_base == NULL)
+		return;
+
+	/*
+	 * Adjust the PMSU configuration to wait for WFI signal, enable
+	 * IRQ and FIQ as wakeup events, set wait for snoop queue empty
+	 * indication and mask IRQ and FIQ from CPU
+	 */
+	reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
+	reg |= PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT    |
+	       PMSU_STATUS_AND_MASK_IRQ_WAKEUP       |
+	       PMSU_STATUS_AND_MASK_FIQ_WAKEUP       |
+	       PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT |
+	       PMSU_STATUS_AND_MASK_IRQ_MASK         |
+	       PMSU_STATUS_AND_MASK_FIQ_MASK;
+	writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
+
+	reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
+	/* ask HW to power down the L2 Cache if needed */
+	if (deepidle)
+		reg |= PMSU_CONTROL_AND_CONFIG_L2_PWDDN;
+
+	/* request power down */
+	reg |= PMSU_CONTROL_AND_CONFIG_PWDDN_REQ;
+	writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
+
+	/* Disable snoop disable by HW - SW is taking care of it */
+	reg = readl(pmsu_mp_base + PMSU_CPU_POWER_DOWN_CONTROL(hw_cpu));
+	reg |= PMSU_CPU_POWER_DOWN_DIS_SNP_Q_SKIP;
+	writel(reg, pmsu_mp_base + PMSU_CPU_POWER_DOWN_CONTROL(hw_cpu));
+}
+
+static noinline int do_armada_370_xp_cpu_suspend(unsigned long deepidle)
+{
+	armada_370_xp_pmsu_idle_prepare(deepidle);
+
+	v7_exit_coherency_flush(all);
+
+	ll_disable_coherency();
+
+	dsb();
+
+	wfi();
+
+	/* If we are here, wfi failed. As processors run out of
+	 * coherency for some time, tlbs might be stale, so flush them
+	 */
+	local_flush_tlb_all();
+
+	ll_enable_coherency();
+
+	/* Test the CR_C bit and set it if it was cleared */
+	asm volatile(
+	"mrc	p15, 0, r0, c1, c0, 0 \n\t"
+	"tst	r0, #(1 << 2) \n\t"
+	"orreq	r0, r0, #(1 << 2) \n\t"
+	"mcreq	p15, 0, r0, c1, c0, 0 \n\t"
+	"isb	"
+	: : : "r0");
+
+	pr_warn("Failed to suspend the system\n");
+
+	return 0;
+}
+
+static int armada_370_xp_cpu_suspend(unsigned long deepidle)
+{
+	return cpu_suspend(deepidle, do_armada_370_xp_cpu_suspend);
+}
+
+/* No locking is needed because we only access per-CPU registers */
+static noinline void armada_370_xp_pmsu_idle_restore(void)
+{
+	unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
+	u32 reg;
+
+	if (pmsu_mp_base == NULL)
+		return;
+
+	/* cancel ask HW to power down the L2 Cache if possible */
+	reg = readl(pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
+	reg &= ~PMSU_CONTROL_AND_CONFIG_L2_PWDDN;
+	writel(reg, pmsu_mp_base + PMSU_CONTROL_AND_CONFIG(hw_cpu));
+
+	/* cancel Enable wakeup events and mask interrupts */
+	reg = readl(pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
+	reg &= ~(PMSU_STATUS_AND_MASK_IRQ_WAKEUP | PMSU_STATUS_AND_MASK_FIQ_WAKEUP);
+	reg &= ~PMSU_STATUS_AND_MASK_CPU_IDLE_WAIT;
+	reg &= ~PMSU_STATUS_AND_MASK_SNP_Q_EMPTY_WAIT;
+	reg &= ~(PMSU_STATUS_AND_MASK_IRQ_MASK | PMSU_STATUS_AND_MASK_FIQ_MASK);
+	writel(reg, pmsu_mp_base + PMSU_STATUS_AND_MASK(hw_cpu));
+}
+
+static int armada_370_xp_cpu_pm_notify(struct notifier_block *self,
+				    unsigned long action, void *hcpu)
+{
+	if (action == CPU_PM_ENTER) {
+		unsigned int hw_cpu = cpu_logical_map(smp_processor_id());
+		mvebu_pmsu_set_cpu_boot_addr(hw_cpu, armada_370_xp_cpu_resume);
+	} else if (action == CPU_PM_EXIT) {
+		armada_370_xp_pmsu_idle_restore();
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block armada_370_xp_cpu_pm_notifier = {
+	.notifier_call = armada_370_xp_cpu_pm_notify,
+};
+
+int __init armada_370_xp_cpu_pm_init(void)
+{
+	struct device_node *np;
+
+	/*
+	 * Check that all the requirements are available to enable
+	 * cpuidle. So far, it is only supported on Armada XP, cpuidle
+	 * needs the coherency fabric and the PMSU enabled
+	 */
+
+	if (!of_machine_is_compatible("marvell,armadaxp"))
+		return 0;
+
+	np = of_find_compatible_node(NULL, NULL, "marvell,coherency-fabric");
+	if (!np)
+		return 0;
+	of_node_put(np);
+
+	np = of_find_matching_node(NULL, of_pmsu_table);
+	if (!np)
+		return 0;
+	of_node_put(np);
+
+	armada_370_xp_pmsu_enable_l2_powerdown_onidle();
+	armada_xp_cpuidle_device.dev.platform_data = armada_370_xp_cpu_suspend;
+	platform_device_register(&armada_xp_cpuidle_device);
+	cpu_pm_register_notifier(&armada_370_xp_cpu_pm_notifier);
+
+	return 0;
+}
+
+arch_initcall(armada_370_xp_cpu_pm_init);
+early_initcall(armada_370_xp_pmsu_init);