armv8: pm: add rcpm module support

The Run Control and Power Management (RCPM) module communicates
with embedded cores, coherency modules, and other device platform
module to provide run control and power management functionality

Signed-off-by: Tang Yuantian <andy.tang@nxp.com>

2 files changed, 155 insertions, 0 deletions

diff --git a/drivers/soc/fsl/Makefile b/drivers/soc/fsl/Makefile
index 75e1f53..954405f 100644
--- a/drivers/soc/fsl/Makefile
+++ b/drivers/soc/fsl/Makefile
@@ -5,3 +5,4 @@
 obj-$(CONFIG_FSL_DPAA)                 += qbman/
 obj-$(CONFIG_QUICC_ENGINE)		+= qe/
 obj-$(CONFIG_CPM)			+= qe/
+obj-$(CONFIG_SUSPEND)			+= rcpm.o
diff --git a/drivers/soc/fsl/rcpm.c b/drivers/soc/fsl/rcpm.c
new file mode 100644
index 0000000..a6a31c8
--- /dev/null
+++ b/drivers/soc/fsl/rcpm.c
@@ -0,0 +1,154 @@
+/*
+ * Run Control and Power Management (RCPM) driver
+ *
+ * Copyright 2016 NXP
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#define pr_fmt(fmt) "RCPM: %s: " fmt, __func__
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/of_platform.h>
+#include <linux/of_address.h>
+#include <linux/suspend.h>
+
+/* RCPM register offset */
+#define RCPM_IPPDEXPCR0			0x140
+
+#define RCPM_WAKEUP_CELL_SIZE	2
+
+struct rcpm_config {
+	int ipp_num;
+	int ippdexpcr_offset;
+	u32 ippdexpcr[2];
+	void *rcpm_reg_base;
+};
+
+static struct rcpm_config *rcpm;
+
+static inline void rcpm_reg_write(u32 offset, u32 value)
+{
+	iowrite32be(value, rcpm->rcpm_reg_base + offset);
+}
+
+static inline u32 rcpm_reg_read(u32 offset)
+{
+	return ioread32be(rcpm->rcpm_reg_base + offset);
+}
+
+static void rcpm_wakeup_fixup(struct device *dev, void *data)
+{
+	struct device_node *node = dev ? dev->of_node : NULL;
+	u32 value[RCPM_WAKEUP_CELL_SIZE];
+	int ret, i;
+
+	if (!dev || !node || !device_may_wakeup(dev))
+		return;
+
+	/*
+	 * Get the values in the "rcpm-wakeup" property.
+	 * Three values are:
+	 * The first is a pointer to the RCPM node.
+	 * The second is the value of the ippdexpcr0 register.
+	 * The third is the value of the ippdexpcr1 register.
+	 */
+	ret = of_property_read_u32_array(node, "fsl,rcpm-wakeup",
+					 value, RCPM_WAKEUP_CELL_SIZE);
+	if (ret)
+		return;
+
+	pr_debug("wakeup source: the device %s\n", node->full_name);
+
+	for (i = 0; i < rcpm->ipp_num; i++)
+		rcpm->ippdexpcr[i] |= value[i + 1];
+}
+
+static int rcpm_suspend_prepare(void)
+{
+	int i;
+
+	BUG_ON(!rcpm);
+
+	for (i = 0; i < rcpm->ipp_num; i++)
+		rcpm->ippdexpcr[i] = 0;
+
+	dpm_for_each_dev(NULL, rcpm_wakeup_fixup);
+
+	for (i = 0; i < rcpm->ipp_num; i++) {
+		rcpm_reg_write(rcpm->ippdexpcr_offset + 4 * i,
+			       rcpm->ippdexpcr[i]);
+		pr_debug("ippdexpcr%d = 0x%x\n", i, rcpm->ippdexpcr[i]);
+	}
+
+	return 0;
+}
+
+static int rcpm_suspend_notifier_call(struct notifier_block *bl,
+				      unsigned long state,
+				      void *unused)
+{
+	switch (state) {
+	case PM_SUSPEND_PREPARE:
+		rcpm_suspend_prepare();
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static struct rcpm_config rcpm_default_config = {
+	.ipp_num = 1,
+	.ippdexpcr_offset = RCPM_IPPDEXPCR0,
+};
+
+static const struct of_device_id rcpm_matches[] = {
+	{
+		.compatible = "fsl,qoriq-rcpm-2.1",
+		.data = &rcpm_default_config,
+	},
+	{}
+};
+
+static struct notifier_block rcpm_suspend_notifier = {
+	.notifier_call = rcpm_suspend_notifier_call,
+};
+
+static int __init layerscape_rcpm_init(void)
+{
+	const struct of_device_id *match;
+	struct device_node *np;
+
+	np = of_find_matching_node_and_match(NULL, rcpm_matches, &match);
+	if (!np) {
+		pr_err("Can't find the RCPM node.\n");
+		return -EINVAL;
+	}
+
+	if (match->data)
+		rcpm = (struct rcpm_config *)match->data;
+	else
+		return -EINVAL;
+
+	rcpm->rcpm_reg_base = of_iomap(np, 0);
+	of_node_put(np);
+	if (!rcpm->rcpm_reg_base)
+		return -ENOMEM;
+
+	register_pm_notifier(&rcpm_suspend_notifier);
+
+	pr_info("The RCPM driver initialized.\n");
+
+	return 0;
+}
+
+subsys_initcall(layerscape_rcpm_init);