iot2050: Add support for configuring M.2 connector
The M.2 slots of the related IOT2050 variant need to be configured
according to the plugged cards. This tries to detect the card using the
M.2 configuration pins of the B-key slot. If that fails, a U-Boot
environment variable can be set to configure manually. This variable is
write-permitted also in secure boot mode as it is not able to undermine
the integrity of the booted system.
The configuration is then applied to mux the serdes and to fix up the
device tree passed to or loaded by the bootloader. The fix-ups are
coming from device tree overlays that are embedded into the firmware
image and there also integrity protected. The OS remains free to load
a device tree to which they do not apply: U-Boot will not fail to boot
in that case.
Based on original patch by Chao Zeng.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
diff --git a/arch/arm/dts/k3-am65-iot2050-boot-image.dtsi b/arch/arm/dts/k3-am65-iot2050-boot-image.dtsi
index a2fc8bb..03ccc54 100644
--- a/arch/arm/dts/k3-am65-iot2050-boot-image.dtsi
+++ b/arch/arm/dts/k3-am65-iot2050-boot-image.dtsi
@@ -61,6 +61,36 @@
};
};
+#ifdef CONFIG_TARGET_IOT2050_A53_PG2
+ bkey-usb3-overlay {
+ description = "M.2-bkey-usb3-overlay";
+ type = "blob";
+ load = <0x82100000>;
+ arch = "arm64";
+ compression = "none";
+ blob-ext {
+ filename = "k3-am6548-iot2050-advanced-m2-bkey-usb3-overlay.dtbo";
+ };
+ hash {
+ algo = "sha256";
+ };
+ };
+
+ bkey-ekey-pcie-overlay {
+ description = "M.2-bkey-ekey-pcie-overlay";
+ type = "blob";
+ load = <0x82110000>;
+ arch = "arm64";
+ compression = "none";
+ blob-ext {
+ filename = "k3-am6548-iot2050-advanced-m2-bkey-ekey-pcie-overlay.dtbo";
+ };
+ hash {
+ algo = "sha256";
+ };
+ };
+#endif
+
#ifdef CONFIG_WDT_K3_RTI_FW_FILE
k3-rti-wdt-firmware {
type = "firmware";
@@ -84,9 +114,15 @@
description = "NAME";
firmware = "u-boot";
fdt = "fdt-SEQ";
-#ifdef CONFIG_WDT_K3_RTI_FW_FILE
- loadables = "k3-rti-wdt-firmware";
+ loadables =
+#ifdef CONFIG_TARGET_IOT2050_A53_PG2
+ "bkey-usb3-overlay",
+ "bkey-ekey-pcie-overlay",
#endif
+#ifdef CONFIG_WDT_K3_RTI_FW_FILE
+ "k3-rti-wdt-firmware",
+#endif
+ <>;
signature {
sign-images = "firmware", "fdt", "loadables";
};