arch/x86: Init firmware pointer for EC SMSC KBC1098/KBC1126 at build time
According to util/kbc1126/README.md, for these ECs to work, the
address and size of their two firmware should be written to $s-0x100`
(`$s` means the image size, done with kbc1126_ec_insert), which means
that every existing section (especially those used to store code)
should not overlap this address, otherwise the bootblock will get
damaged when inserting firmwares of the EC.
In this commit, ecfw_ptr is a structure initialized at build time
according to CONFIG_KBC1126_FW1_OFFSET and CONFIG_KBC1126_FW2_OFFSET
(to do so, they should be redefined as hex), and linked to
CONFIG_ECFW_PTR_ADDR within bootblock, so kbc1126_ec_insert is not
needed at build time any more.
Test passed on Elitebook Folio 9470m.
Signed-off-by: Bill XIE <persmule@hardenedlinux.org>
Change-Id: I4f0de0c4d7283e630242fbe84a46e0547783c49e
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51671
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/src/arch/x86/Kconfig b/src/arch/x86/Kconfig
index 6af3fa8..207654d 100644
--- a/src/arch/x86/Kconfig
+++ b/src/arch/x86/Kconfig
@@ -340,4 +340,23 @@
string
default "src/arch/x86/memlayout.ld"
+# Some EC need an "EC firmware pointer" (a data structure hinting the address
+# of its firmware blobs) being put at a fixed position. Its space
+# (__section__(".ecfw_ptr")) should be reserved if it lies in the range of a
+# stage. Different EC may have different format and/or value for it. The actual
+# address of EC firmware pointer should be provided in the Kconfig of the EC
+# requiring it, and its value could be filled by linking a read-only global
+# data object to the section above.
+
+config ECFW_PTR_ADDR
+ hex
+ help
+ Address of reserved space for EC firmware pointer, which should not
+ overlap other data such as reset vector or FIT pointer if present.
+
+config ECFW_PTR_SIZE
+ int
+ help
+ Size of reserved space for EC firmware pointer
+
endif