The Renesas RZ/N1 Family (Part #R9A06G0xx) needs a small driver
to reboot the Cortex-A7 cores. This driver is a sub driver of
the sysctrl MFD.
Signed-off-by: Michel Pollet <michel.pollet@xxxxxxxxxxxxxx>
---
drivers/power/reset/Kconfig | 7 +++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/rzn1-reboot.c | 105 ++++++++++++++++++++++++++++++++++++++
3 files changed, 113 insertions(+)
create mode 100644 drivers/power/reset/rzn1-reboot.c
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index df58fc8..1416d88 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -144,6 +144,13 @@ config POWER_RESET_RESTART
Instead they restart, and u-boot holds the SoC until the
user presses a key. u-boot then boots into Linux.
+config POWER_RESET_RZN1
+ bool "Renesas RZ/N1 reboot driver"
+ depends on ARCH_RZN1
+ help
+ This driver allows rebooting the CA7 cores of the
+ Renesas RZ/N1 Family of SoC (Part # R9A06G0xx).
+
config POWER_RESET_ST
bool "ST restart driver"
depends on ARCH_STI
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 7778c74..bad9702 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_POWER_RESET_PIIX4_POWEROFF) += piix4-poweroff.o
obj-$(CONFIG_POWER_RESET_LTC2952) += ltc2952-poweroff.o
obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
obj-$(CONFIG_POWER_RESET_RESTART) += restart-poweroff.o
+obj-$(CONFIG_POWER_RESET_RZN1) += rzn1-reboot.o
obj-$(CONFIG_POWER_RESET_ST) += st-poweroff.o
obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o
obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o
diff --git a/drivers/power/reset/rzn1-reboot.c b/drivers/power/reset/rzn1-reboot.c
new file mode 100644
index 0000000..54fdd81
--- /dev/null
+++ b/drivers/power/reset/rzn1-reboot.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RZ/N1 reboot driver
+ *
+ * Copyright (C) 2018 Renesas Electronics Europe Limited
+ *
+ * Michel Pollet <michel.pollet@xxxxxxxxxxxxxx>, <buserror@xxxxxxxxx>
+ * Derived from zx-reboot.c
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
+
+/* Definitions from the SDK rzn1-sysctrl.h autogenerated file */
+#define RZN1_SYSCTRL_REG_RSTEN 0x120
+#define RZN1_SYSCTRL_REG_RSTEN_MRESET_EN 0
+#define RZN1_SYSCTRL_REG_RSTEN_WDA7RST_EN 1
+#define RZN1_SYSCTRL_REG_RSTEN_WDA7RST_EN_MASK 0x6
+#define RZN1_SYSCTRL_REG_RSTEN_WDM3RST_EN 3
+#define RZN1_SYSCTRL_REG_RSTEN_CM3LOCKUPRST_EN 4
+#define RZN1_SYSCTRL_REG_RSTEN_CM3SYSRESET_EN 5
+#define RZN1_SYSCTRL_REG_RSTEN_SWRST_EN 6
+#define RZN1_SYSCTRL_REG_RSTCTRL 0x198
+#define RZN1_SYSCTRL_REG_RSTCTRL_WDA7RST_REQ 1
+#define RZN1_SYSCTRL_REG_RSTCTRL_WDA7RST_REQ_MASK 0x6
+#define RZN1_SYSCTRL_REG_RSTCTRL_WDM3RST_REQ 3
+#define RZN1_SYSCTRL_REG_RSTCTRL_CM3LOCKUPRST_REQ 4
+#define RZN1_SYSCTRL_REG_RSTCTRL_CM3SYSRESET_REQ 5
+#define RZN1_SYSCTRL_REG_RSTCTRL_SWRST_REQ 6
+
+static struct regmap *sysctrl;
+
+static int rzn1_reboot_handler(struct notifier_block *this,
+ unsigned long mode, void *cmd)
+{
+ regmap_write_bits(sysctrl,
+ RZN1_SYSCTRL_REG_RSTEN,
+ BIT(RZN1_SYSCTRL_REG_RSTEN_SWRST_EN) |
+ BIT(RZN1_SYSCTRL_REG_RSTEN_MRESET_EN),
+ BIT(RZN1_SYSCTRL_REG_RSTEN_SWRST_EN) |
+ BIT(RZN1_SYSCTRL_REG_RSTEN_MRESET_EN));
+ regmap_write_bits(sysctrl,
+ RZN1_SYSCTRL_REG_RSTCTRL,
+ BIT(RZN1_SYSCTRL_REG_RSTCTRL_SWRST_REQ),
+ BIT(RZN1_SYSCTRL_REG_RSTCTRL_SWRST_REQ));
+
+ mdelay(50);
+ pr_emerg("Unable to restart system\n");
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block rzn1_reboot_nb = {
+ .notifier_call = rzn1_reboot_handler,
+ .priority = 128,
+};
+
+static int rzn1_reboot_probe(struct platform_device *pdev)
+{
+ int err;
+ struct device *parent;
+
+ parent = pdev->dev.parent;
+ if (!parent || !parent->of_node)
+ dev_err(&pdev->dev, "couldn't find sysctrl node\n");
+ return -ENODEV;
+ }
+ sysctrl = syscon_node_to_regmap(parent->of_node);
+ if (IS_ERR(sysctrl)) {
+ dev_err(&pdev->dev, "couldn't find find regmap\n");
+ return PTR_ERR(sysctrl);
+ }
+ err = register_restart_handler(&rzn1_reboot_nb);
+ if (err) {
+ dev_err(&pdev->dev, "register restart handler failed(err=%d)\n",
+ err);
+ }
+
+ return err;
+}
+
+static const struct of_device_id rzn1_reboot_of_match[] = {
+ { .compatible = "renesas,rzn1-reboot" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, rzn1_reboot_of_match);
+
+static struct platform_driver rzn1_reboot_driver = {
+ .probe = rzn1_reboot_probe,
+ .driver = {
+ .name = "rzn1-reboot",
+ .of_match_table = rzn1_reboot_of_match,
+ },
+};
+module_platform_driver(rzn1_reboot_driver);
+
+MODULE_DESCRIPTION("RZ/N1 reboot driver");
+MODULE_AUTHOR("Michel Pollet <michel.pollet@xxxxxxxxxxxxxx>, <buserror@xxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
--
2.7.4
