From ebb73de1687cfd6449f492b54cc2f32b4b0ce9c5 Mon Sep 17 00:00:00 2001 From: Philipp Tomsich Date: Tue, 27 Nov 2018 23:00:18 +0100 Subject: 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 Tested-by: Klaus Goger --- doc/device-tree-bindings/chosen.txt | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'doc/device-tree-bindings') diff --git a/doc/device-tree-bindings/chosen.txt b/doc/device-tree-bindings/chosen.txt index 86c533ad6d3..395c9501e3b 100644 --- a/doc/device-tree-bindings/chosen.txt +++ b/doc/device-tree-bindings/chosen.txt @@ -42,6 +42,36 @@ Example }; }; +u-boot,bootcount-device property +-------------------------------- + +In a DM-based system, the bootcount may be stored in a device known to +the DM framework (e.g. in a battery-backed SRAM area within a RTC +device) managed by a device conforming to UCLASS_BOOTCOUNT. If +multiple such devices are present in a system concurrently, then the +u-boot,bootcount-device property can select the preferred target. + +Example +------- +/ { + chosen { + u-boot,bootcount-device = &bootcount-rv3029; + }; + + bootcount-rv3029: bootcount@0 { + compatible = "u-boot,bootcount-rtc"; + rtc = &rv3029; + offset = <0x38>; + }; + + i2c2 { + rv3029: rtc@56 { + compatible = "mc,rv3029"; + reg = <0x56>; + }; + }; +}; + u-boot,spl-boot-order property ------------------------------ -- cgit v1.2.3