reboot-mode: Add NVMEM reboot mode

This adds an NVMEM reboot mode driver, similar to Linux's
implementation. This allows using the same device tree binding for Linux
and U-Boot in most cases.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/MAINTAINERS b/MAINTAINERS
index 237f3940b435e3a6f9aefa1c1c05d5cdce6a23d0..b2de50ccfc882e2b082fb3b62e9563cb3aa9431c 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1198,6 +1198,7 @@ M:        Sean Anderson <seanga2@gmail.com>
 S:     Maintained
 F:     doc/api/nvmem.rst
 F:     drivers/misc/nvmem.c
+F:     drivers/reboot-mode/reboot-mode-nvmem.c
 F:     include/nvmem.h
 
 NXP C45 TJA11XX PHY DRIVER

diff --git a/drivers/reboot-mode/Kconfig b/drivers/reboot-mode/Kconfig
index 63ea18cdf095774e898de11e913ea1f1fb977171..d57baacc93d1203ece50abc44c7c774a7d3f89fe 100644 (file)
--- a/drivers/reboot-mode/Kconfig
+++ b/drivers/reboot-mode/Kconfig
@@ -30,4 +30,11 @@ config DM_REBOOT_MODE_RTC
                a device in a specific mode by using a register(s) that can be controlled
                outside U-Boot (e.g. Kernel).
 
+config REBOOT_MODE_NVMEM
+       bool "Use NVMEM reboot mode"
+       depends on DM_REBOOT_MODE && NVMEM
+       help
+         Use any kind of non-volatile memory (EEPROM, RTC, etc) to control the
+         reboot mode.
+
 endmenu

diff --git a/drivers/reboot-mode/Makefile b/drivers/reboot-mode/Makefile
index 2c13780ced478527002b56b46b73760d5fad8baa..48c8ab7fe71267f7a88a0ceceb017d4f4b7f984c 100644 (file)
--- a/drivers/reboot-mode/Makefile
+++ b/drivers/reboot-mode/Makefile
@@ -7,3 +7,4 @@
 obj-$(CONFIG_DM_REBOOT_MODE) += reboot-mode-uclass.o
 obj-$(CONFIG_DM_REBOOT_MODE_GPIO) += reboot-mode-gpio.o
 obj-$(CONFIG_DM_REBOOT_MODE_RTC) += reboot-mode-rtc.o
+obj-$(CONFIG_REBOOT_MODE_NVMEM) += reboot-mode-nvmem.o

diff --git a/drivers/reboot-mode/reboot-mode-nvmem.c b/drivers/reboot-mode/reboot-mode-nvmem.c
new file mode 100644 (file)
index 0000000..da41ca4
--- /dev/null
+++ b/drivers/reboot-mode/reboot-mode-nvmem.c
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2022 Sean Anderson <sean.anderson@seco.com>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <nvmem.h>
+#include <reboot-mode/reboot-mode.h>
+
+/**
+ * struct nvmem_reboot_mode_priv - Private data for the nvmem reboot mode device
+ * @cell: The nvmem cell to store the mode in
+ */
+struct nvmem_reboot_mode_priv {
+       struct nvmem_cell cell;
+};
+
+static int reboot_mode_get(struct udevice *dev, u32 *mode)
+{
+       struct nvmem_reboot_mode_priv *priv = dev_get_priv(dev);
+
+       return nvmem_cell_read(&priv->cell, mode, sizeof(*mode));
+}
+
+static int reboot_mode_set(struct udevice *dev, u32 mode)
+{
+       struct nvmem_reboot_mode_priv *priv = dev_get_priv(dev);
+
+       return nvmem_cell_write(&priv->cell, &mode, sizeof(mode));
+}
+
+static const struct reboot_mode_ops nvmem_reboot_mode_ops = {
+       .get = reboot_mode_get,
+       .set = reboot_mode_set,
+};
+
+static int reboot_mode_probe(struct udevice *dev)
+{
+       struct nvmem_reboot_mode_priv *priv = dev_get_priv(dev);
+
+       return nvmem_cell_get_by_name(dev, "reboot-mode", &priv->cell);
+}
+
+static const struct udevice_id nvmem_reboot_mode_ids[] = {
+       { .compatible = "nvmem-reboot-mode" },
+       { }
+};
+
+U_BOOT_DRIVER(nvmem_reboot_mode) = {
+       .name = "nvmem-reboot-mode",
+       .id = UCLASS_REBOOT_MODE,
+       .of_match = nvmem_reboot_mode_ids,
+       .probe = reboot_mode_probe,
+       .priv_auto = sizeof(struct nvmem_reboot_mode_priv),
+       .ops = &nvmem_reboot_mode_ops,
+};