doc/icE1usb: gateware is stored in flash and can be upgraded
Change-Id: I319ff4e75ba76543e562822b6b6d5968bccef237
diff --git a/doc/manuals/chapters/gateware.adoc b/doc/manuals/chapters/gateware.adoc
index 03487e1..a515cb1 100644
--- a/doc/manuals/chapters/gateware.adoc
+++ b/doc/manuals/chapters/gateware.adoc
@@ -6,6 +6,9 @@
picoRISCV soft-core running the [[firmware]] as well as the USB
device peripheral talking to the host PC.
+The gateware is stored in binary form on the device-internal
+non-volatile memory (SPI flash). It is field-upgradeable via USB.
+
As an OSHW project, all of it is available in source code format
at https://git.osmocom.org/osmo-e1-hardware/tree/gateware/icE1usb