include/bitfield.h: Assure new bitfield value doesn't touch unwanted bits

[karo-tx-uboot.git] / README

diff --git a/README b/README
index 10e8f33f70ebb2d6043e9b1fdbbfe2b06a3aea0d..fe21bbf9824a72ace81215579f4028c5f91d1802 100644 (file)
--- a/README
+++ b/README
@@ -5202,6 +5202,18 @@ This firmware often needs to be loaded during U-Boot booting.
 - CONFIG_SYS_MEM_TOP_HIDE_MIN
        Define minimum DDR size to be hided from top of the DDR memory
 
+Reproducible builds
+-------------------
+
+In order to achieve reproducible builds, timestamps used in the U-Boot build
+process have to be set to a fixed value.
+
+This is done using the SOURCE_DATE_EPOCH environment variable.
+SOURCE_DATE_EPOCH is to be set on the build host's shell, not as a configuration
+option for U-Boot or an environment variable in U-Boot.
+
+SOURCE_DATE_EPOCH should be set to a number of seconds since the epoch, in UTC.
+
 Building the Software:
 ======================