MLK-13733-2 ARM: imx: add pm rpmsg for i.mx7ulp

Add PM RPMSG for i.MX7ULP power management, currently
it handles heart beat function which will notify M4
that linux is alive every 30 seconds, and when system
enters/exit VLLS mode, it will notify M4 for proper
power management.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>

4 files changed, 176 insertions, 1 deletions

diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index 91d08689a2e1..e6eb59c7aefd 100644
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -107,7 +107,7 @@ obj-$(CONFIG_SOC_IMX6SX) += mach-imx6sx.o ddr3_freq_imx6sx.o \
 obj-$(CONFIG_SOC_IMX6UL) += mach-imx6ul.o ddr3_freq_imx6sx.o \
 			    lpddr2_freq_imx6sx.o
 obj-$(CONFIG_SOC_IMX7D) += mach-imx7d.o
-obj-$(CONFIG_SOC_IMX7ULP) += mach-imx7ulp.o pm-imx7ulp.o
+obj-$(CONFIG_SOC_IMX7ULP) += mach-imx7ulp.o pm-imx7ulp.o pm-rpmsg.o
 
 ifeq ($(CONFIG_SUSPEND),y)
 AFLAGS_suspend-imx6.o :=-Wa,-march=armv7-a
diff --git a/arch/arm/mach-imx/common.h b/arch/arm/mach-imx/common.h
index 154cd0b286e8..c6cd31386231 100644
--- a/arch/arm/mach-imx/common.h
+++ b/arch/arm/mach-imx/common.h
@@ -1,5 +1,6 @@
 /*
  * Copyright 2004-2016 Freescale Semiconductor, Inc. All Rights Reserved.
+ * Copyright 2017 NXP
  */
 
 /*
@@ -200,6 +201,7 @@ void imx7ulp_cpu_resume(void);
 void imx6_suspend(void __iomem *ocram_vbase);
 void imx7_suspend(void __iomem *ocram_vbase);
 void imx7ulp_suspend(void __iomem *ocram_vbase);
+void pm_vlls_notify_m4(bool enter);
 #else
 static inline void v7_cpu_resume(void) {}
 static inline void ca7_cpu_resume(void) {}
@@ -209,6 +211,7 @@ static inline void imx7ulp_cpu_resume(void) {}
 static inline void imx6_suspend(void __iomem *ocram_vbase) {}
 static inline void imx7_suspend(void __iomem *ocram_vbase) {}
 static inline void imx7ulp_suspend(void __iomem *ocram_vbase) {}
+void pm_vlls_notify_m4(bool enter) {}
 #endif
 
 void imx6_pm_ccm_init(const char *ccm_compat);
diff --git a/arch/arm/mach-imx/pm-imx7ulp.c b/arch/arm/mach-imx/pm-imx7ulp.c
index eb58f5f40985..bef6d938d945 100644
--- a/arch/arm/mach-imx/pm-imx7ulp.c
+++ b/arch/arm/mach-imx/pm-imx7ulp.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Copyright 2017 NXP
  *
  * The code contained herein is licensed under the GNU General Public
  * License. You may obtain a copy of the GNU General Public License
@@ -450,6 +451,7 @@ static int imx7ulp_pm_enter(suspend_state_t state)
 		imx7ulp_set_lpm(RUN);
 		break;
 	case PM_SUSPEND_MEM:
+		pm_vlls_notify_m4(true);
 		imx7ulp_gpio_save();
 		imx7ulp_scg1_save();
 		imx7ulp_pcc2_save();
@@ -470,6 +472,7 @@ static int imx7ulp_pm_enter(suspend_state_t state)
 		imx7ulp_tpm_restore();
 		imx7ulp_iomuxc_restore();
 		imx7ulp_set_lpm(RUN);
+		pm_vlls_notify_m4(false);
 		break;
 	default:
 		return -EINVAL;
diff --git a/arch/arm/mach-imx/pm-rpmsg.c b/arch/arm/mach-imx/pm-rpmsg.c
new file mode 100644
index 000000000000..680f2132d3f6
--- /dev/null
+++ b/arch/arm/mach-imx/pm-rpmsg.c
@@ -0,0 +1,169 @@
+/*
+ * Copyright 2017 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.
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_qos.h>
+#include <linux/rpmsg.h>
+#include <linux/uaccess.h>
+#include <linux/virtio.h>
+
+#define RPMSG_TIMEOUT 1000
+
+#define PM_RPMSG_LIFE_CYCLE	1
+#define PM_RPMSG_VERSION	1
+#define PM_RPMSG_TYPE		2
+
+enum pm_rpmsg_cmd {
+	PM_RPMSG_MODE,
+	PM_RPMSG_HEART_BEAT,
+};
+
+enum pm_rpmsg_power_mode {
+	PM_RPMSG_HSRUN,
+	PM_RPMSG_RUN,
+	PM_RPMSG_VLPR,
+	PM_RPMSG_WAIT,
+	PM_RPMSG_VLPS,
+	PM_RPMSG_VLLS,
+};
+
+struct pm_rpmsg_info {
+	struct rpmsg_device *rpdev;
+	struct device *dev;
+	struct pm_rpmsg_data *msg;
+	struct pm_qos_request pm_qos_req;
+};
+
+static struct pm_rpmsg_info pm_rpmsg;
+
+static struct delayed_work heart_beat_work;
+
+struct pm_rpmsg_data {
+	u8 cmd;
+	u8 type;
+	u8 version;
+	u8 cat;
+	u32 data;
+};
+
+static int pm_send_message(struct pm_rpmsg_data *msg,
+			struct pm_rpmsg_info *info)
+{
+	int err;
+
+	if (!info->rpdev) {
+		dev_dbg(info->dev,
+			"rpmsg channel not ready, m4 image ready?\n");
+		return -EINVAL;
+	}
+
+	pm_qos_add_request(&info->pm_qos_req,
+		PM_QOS_CPU_DMA_LATENCY, 0);
+
+	err = rpmsg_send(info->rpdev->ept, (void *)msg,
+			    sizeof(struct pm_rpmsg_data));
+
+	pm_qos_remove_request(&info->pm_qos_req);
+
+	return err;
+}
+
+void pm_vlls_notify_m4(bool enter)
+{
+	struct pm_rpmsg_data msg;
+
+	msg.cat = PM_RPMSG_LIFE_CYCLE;
+	msg.version = PM_RPMSG_VERSION;
+	msg.type = PM_RPMSG_TYPE;
+	msg.cmd = PM_RPMSG_MODE;
+	msg.data = enter ? PM_RPMSG_VLLS : PM_RPMSG_RUN;
+
+	pm_send_message(&msg, &pm_rpmsg);
+}
+
+static void pm_heart_beat_work_handler(struct work_struct *work)
+{
+	struct pm_rpmsg_data msg;
+
+	msg.cat = PM_RPMSG_LIFE_CYCLE;
+	msg.version = PM_RPMSG_VERSION;
+	msg.type = PM_RPMSG_TYPE;
+	msg.cmd = PM_RPMSG_HEART_BEAT;
+	msg.data = 0;
+
+	pm_send_message(&msg, &pm_rpmsg);
+
+	schedule_delayed_work(&heart_beat_work,
+		msecs_to_jiffies(30000));
+}
+
+static int pm_rpmsg_probe(struct rpmsg_device *rpdev)
+{
+	pm_rpmsg.rpdev = rpdev;
+
+	dev_info(&rpdev->dev, "new channel: 0x%x -> 0x%x!\n",
+			rpdev->src, rpdev->dst);
+
+	INIT_DELAYED_WORK(&heart_beat_work,
+		pm_heart_beat_work_handler);
+
+	schedule_delayed_work(&heart_beat_work,
+		msecs_to_jiffies(10000));
+
+	pm_vlls_notify_m4(false);
+
+	return 0;
+}
+
+static int pm_rpmsg_cb(struct rpmsg_device *rpdev, void *data, int len,
+			void *priv, u32 src)
+{
+	return 0;
+}
+
+static void pm_rpmsg_remove(struct rpmsg_device *rpdev)
+{
+	dev_info(&rpdev->dev, "pm rpmsg driver is removed\n");
+}
+
+static struct rpmsg_device_id pm_rpmsg_id_table[] = {
+	{ .name	= "rpmsg-life-cycle-channel" },
+	{ },
+};
+
+static struct rpmsg_driver pm_rpmsg_driver = {
+	.drv.name	= "pm_rpmsg",
+	.drv.owner	= THIS_MODULE,
+	.id_table	= pm_rpmsg_id_table,
+	.probe		= pm_rpmsg_probe,
+	.callback	= pm_rpmsg_cb,
+	.remove		= pm_rpmsg_remove,
+};
+
+static int __init pm_rpmsg_init(void)
+{
+	return register_rpmsg_driver(&pm_rpmsg_driver);
+}
+
+module_init(pm_rpmsg_init);
+
+MODULE_DESCRIPTION("Freescale PM rpmsg driver");
+MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
+MODULE_LICENSE("GPL");