sysreset: Support reset via Renesas RAA215300 PMIC

This patch adds support for resetting a board via the RAA215300 PMIC.

Note that the RAA215300 documentation names the available reset types
differently to u-boot:

  * A "warm" reset via the RAA215300 PMIC will fully reset the SoC
    (CPU & GPIOs), so this corresponds to SYSRESET_COLD.

  * A "cold" reset via the RAA215300 PMIC will cycle all power supply
    rails, so this corresponds to SYSRESET_POWER.

Signed-off-by: Paul Barker <paul.barker.ct@bp.renesas.com>
Reviewed-by: Marek Vasut <marek.vasut+renesas@mailbox.org>

3 files changed, 65 insertions, 0 deletions

diff --git a/drivers/sysreset/Kconfig b/drivers/sysreset/Kconfig
index 0e52f99..49c0787 100644
--- a/drivers/sysreset/Kconfig
+++ b/drivers/sysreset/Kconfig
@@ -229,6 +229,12 @@ config SYSRESET_MPC83XX
 	help
 	  Reboot support for NXP MPC83xx SoCs.
 
+config SYSRESET_RAA215300
+	bool "Support sysreset via Renesas RAA215300 PMIC"
+	depends on PMIC_RAA215300
+	help
+	  Add support for the system reboot via the Renesas RAA215300 PMIC.
+
 endif
 
 endmenu
diff --git a/drivers/sysreset/Makefile b/drivers/sysreset/Makefile
index c9f1c62..e0e7322 100644
--- a/drivers/sysreset/Makefile
+++ b/drivers/sysreset/Makefile
@@ -27,4 +27,5 @@ obj-$(CONFIG_SYSRESET_WATCHDOG) += sysreset_watchdog.o
 obj-$(CONFIG_SYSRESET_RESETCTL) += sysreset_resetctl.o
 obj-$(CONFIG_$(SPL_TPL_)SYSRESET_AT91) += sysreset_at91.o
 obj-$(CONFIG_$(SPL_TPL_)SYSRESET_X86) += sysreset_x86.o
+obj-$(CONFIG_SYSRESET_RAA215300) += sysreset_raa215300.o
 obj-$(CONFIG_TARGET_XTFPGA) += sysreset_xtfpga.o
diff --git a/drivers/sysreset/sysreset_raa215300.c b/drivers/sysreset/sysreset_raa215300.c
new file mode 100644
index 0000000..32dfcb0
--- /dev/null
+++ b/drivers/sysreset/sysreset_raa215300.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2023 Renesas Electronics Corporation
+ */
+
+#include <dm.h>
+#include <power/pmic.h>
+#include <sysreset.h>
+
+#define RAA215300_REG_SWRESET	0x6D
+#define RAA215300_COLD_RESET	BIT(0)
+#define RAA215300_WARM_RESET	BIT(1)
+
+static int raa215300_sysreset_request(struct udevice *dev, enum sysreset_t type)
+{
+	struct udevice *pmic = dev_get_parent(dev);
+	int ret;
+	u8 val;
+
+	/*
+	 * The RAA215300 documentation names the available reset types
+	 * differently to u-boot:
+	 *
+	 *   - A "warm" reset via the RAA215300 PMIC will fully reset the SoC
+	 *     (CPU & GPIOs), so this corresponds to SYSRESET_COLD.
+	 *
+	 *   - A "cold" reset via the RAA215300 PMIC will cycle all power supply
+	 *     rails, so this corresponds to SYSRESET_POWER.
+	 */
+	switch (type) {
+	case SYSRESET_COLD:
+		val = RAA215300_WARM_RESET;
+		break;
+
+	case SYSRESET_POWER:
+		val = RAA215300_COLD_RESET;
+		break;
+
+	default:
+		return -EPROTONOSUPPORT;
+	}
+
+	ret = pmic_reg_write(pmic, RAA215300_REG_SWRESET, val);
+	if (ret)
+		return ret;
+
+	return -EINPROGRESS;
+}
+
+static struct sysreset_ops raa215300_sysreset_ops = {
+	.request = raa215300_sysreset_request,
+};
+
+U_BOOT_DRIVER(raa215300_sysreset) = {
+	.name = "raa215300_sysreset",
+	.id = UCLASS_SYSRESET,
+	.ops = &raa215300_sysreset_ops,
+};