bootcount: add uclass for bootcount
The original bootcount methods do not provide an interface to DM and
rely on a static configuration for I2C devices (e.g. bus, chip-addr,
etc. are configured through defines statically). On a modern system
that exposes multiple devices in a DTS-configurable way, this is less
than optimal and a interface to DM-based devices will be desirable.
This adds a simple driver that is DM-aware and configurable via DTS.
If ambiguous (i.e. multiple bootcount-devices are present) the
/chosen/u-boot,bootcount-device property can be used to select one
bootcount device.
Initially, this provides support for the following DM devices:
* RTC devices
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Tested-by: Klaus Goger <klaus.goger@theobroma-systems.com>
diff --git a/drivers/bootcount/Kconfig b/drivers/bootcount/Kconfig
index 6703363..46571eb 100644
--- a/drivers/bootcount/Kconfig
+++ b/drivers/bootcount/Kconfig
@@ -70,6 +70,14 @@
bool "Boot counter for Atmel AT91SAM9XE"
depends on AT91SAM9XE
+config DM_BOOTCOUNT
+ bool "Boot counter in a device-model device"
+ help
+ Enables reading/writing the bootcount in a device-model based
+ backing store. If an entry in /chosen/u-boot,bootcount-device
+ exists, this will be the preferred bootcount device; otherwise
+ the first available bootcount device will be used.
+
endchoice
config BOOTCOUNT_BOOTLIMIT
diff --git a/drivers/bootcount/Makefile b/drivers/bootcount/Makefile
index 68bc006..81980b3 100644
--- a/drivers/bootcount/Makefile
+++ b/drivers/bootcount/Makefile
@@ -7,3 +7,5 @@
obj-$(CONFIG_BOOTCOUNT_ENV) += bootcount_env.o
obj-$(CONFIG_BOOTCOUNT_I2C) += bootcount_i2c.o
obj-$(CONFIG_BOOTCOUNT_EXT) += bootcount_ext.o
+
+obj-$(CONFIG_DM_BOOTCOUNT) += bootcount-uclass.o
diff --git a/drivers/bootcount/bootcount-uclass.c b/drivers/bootcount/bootcount-uclass.c
new file mode 100644
index 0000000..0689db7
--- /dev/null
+++ b/drivers/bootcount/bootcount-uclass.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2018 Theobroma Systems Design und Consulting GmbH
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <bootcount.h>
+
+int dm_bootcount_get(struct udevice *dev, u32 *bootcount)
+{
+ struct bootcount_ops *ops = bootcount_get_ops(dev);
+
+ assert(ops);
+ if (!ops->get)
+ return -ENOSYS;
+ return ops->get(dev, bootcount);
+}
+
+int dm_bootcount_set(struct udevice *dev, const u32 bootcount)
+{
+ struct bootcount_ops *ops = bootcount_get_ops(dev);
+
+ assert(ops);
+ if (!ops->set)
+ return -ENOSYS;
+ return ops->set(dev, bootcount);
+}
+
+/* Now implement the generic default functions */
+void bootcount_store(ulong val)
+{
+ struct udevice *dev = NULL;
+ ofnode node;
+ const char *propname = "u-boot,bootcount-device";
+ int ret = -ENODEV;
+
+ /*
+ * If there's a preferred bootcount device selected by the user (by
+ * setting '/chosen/u-boot,bootcount-device' in the DTS), try to use
+ * it if available.
+ */
+ node = ofnode_get_chosen_node(propname);
+ if (ofnode_valid(node))
+ ret = uclass_get_device_by_ofnode(UCLASS_BOOTCOUNT, node, &dev);
+
+ /* If there was no user-selected device, use the first available one */
+ if (ret)
+ ret = uclass_get_device(UCLASS_BOOTCOUNT, 0, &dev);
+
+ if (dev)
+ ret = dm_bootcount_set(dev, val);
+
+ if (ret)
+ pr_debug("%s: failed to store 0x%lx\n", __func__, val);
+}
+
+ulong bootcount_load(void)
+{
+ struct udevice *dev = NULL;
+ ofnode node;
+ const char *propname = "u-boot,bootcount-device";
+ int ret = -ENODEV;
+ u32 val;
+
+ /*
+ * If there's a preferred bootcount device selected by the user (by
+ * setting '/chosen/u-boot,bootcount-device' in the DTS), try to use
+ * it if available.
+ */
+ node = ofnode_get_chosen_node(propname);
+ if (ofnode_valid(node))
+ ret = uclass_get_device_by_ofnode(UCLASS_BOOTCOUNT, node, &dev);
+
+ /* If there was no user-selected device, use the first available one */
+ if (ret)
+ ret = uclass_get_device(UCLASS_BOOTCOUNT, 0, &dev);
+
+ if (dev)
+ ret = dm_bootcount_get(dev, &val);
+
+ if (ret)
+ pr_debug("%s: failed to load bootcount\n", __func__);
+
+ /* Return the 0, if the call to dm_bootcount_get failed */
+ return ret ? 0 : val;
+}
+
+UCLASS_DRIVER(bootcount) = {
+ .name = "bootcount",
+ .id = UCLASS_BOOTCOUNT,
+};