dm: core: Add an option to support SPL in read-only memory
Some systems (e.g. x86 APL) run SPL from read-only memory. The device
instances created by dtoc are therefore not writeable. To make things work
we would need to copy the devices to read/write memory.
To avoid this, add an option to use a separate runtime struct for devices,
just as is done for drivers. This can be used to hold information that
changes at runtime, avoiding the need for a copy.
Also add a Kconfig option for read-only SPL, which selects this feature.
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/dts/Kconfig b/dts/Kconfig
index d289752..e6bbdc5 100644
--- a/dts/Kconfig
+++ b/dts/Kconfig
@@ -380,6 +380,17 @@
some code space in U-Boot. This can be disabled if binding is needed,
at the code of some code size increase.
+config SPL_OF_PLATDATA_RT
+ bool "Use a separate struct for device runtime data"
+ depends on SPL_OF_PLATDATA_INST
+ default y
+ help
+ For systems running SPL from read-only memory it is convenient to
+ separate out the runtime information, so that the devices don't need
+ to be copied before being used. This moves the read-write parts of
+ struct udevice (at present just the flags) into a separate struct,
+ which is allocated at runtime.
+
endif
config TPL_OF_PLATDATA
@@ -429,6 +440,17 @@
some code space in U-Boot. This can be disabled if binding is needed,
at the code of some code size increase.
+config TPL_OF_PLATDATA_RT
+ bool "Use a separate struct for device runtime data"
+ depends on TPL_OF_PLATDATA_INST
+ default y
+ help
+ For systems running TPL from read-only memory it is convenient to
+ separate out the runtime information, so that the devices don't need
+ to be copied before being used. This moves the read-write parts of
+ struct udevice (at present just the flags) into a separate struct,
+ which is allocated at runtime.
+
endif
endmenu