diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst
index 9386cffba2..ac31a2bce4 100644
--- a/docs/about/deprecated.rst
+++ b/docs/about/deprecated.rst
@@ -308,13 +308,24 @@ I2C devices connected to the board can be defined via the QEMU command
 line.
 
 Arm ``fp5280g2-bmc`` machine (since 10.2)
-'''''''''''''''''''''''''''''''''''''''''''
+'''''''''''''''''''''''''''''''''''''''''
 
 The ``fp5280g2-bmc`` machine does not rely on any specific device
 models, it can be replaced by the ``ast2500-evb`` machine using the
 ``fmc-model`` option to specify the flash type. The I2C devices
 connected to the board can be defined via the QEMU command line.
 
+Arm ``fby35`` machine (since 10.2)
+''''''''''''''''''''''''''''''''''
+
+The ``fby35`` machine was originally added as an example of a
+multi-SoC system, with the expectation the models would evolve over
+time in an heterogeneous system. This hasn't happened and no public
+firmware is available to boot it. It can be replaced by the
+``ast2700fc``, another multi-SoC machine based on the newer AST2700
+SoCs which are excepted to receive better support in the future.
+
+
 RISC-V default machine option (since 10.0)
 ''''''''''''''''''''''''''''''''''''''''''
 
diff --git a/hw/arm/fby35.c b/hw/arm/fby35.c
index 70d3a99d79..e61a6438fe 100644
--- a/hw/arm/fby35.c
+++ b/hw/arm/fby35.c
@@ -175,6 +175,7 @@ static void fby35_class_init(ObjectClass *oc, const void *data)
     MachineClass *mc = MACHINE_CLASS(oc);
 
     mc->desc = "Meta Platforms fby35";
+    mc->deprecation_reason = "For a multi-soc machine, use 'ast2700fc' instead";
     mc->init = fby35_init;
     mc->no_floppy = 1;
     mc->no_cdrom = 1;