The change to ATF's PRELOADED_BL33_BASE[1] requires respective changes to
SPL_TEXT_BASE on u-boot side. This is necessary to allow the ATF to jump
directly to linux kernel (like in falcon mode) which requires a 2MiB aligned
load address[2]. The current address ATF jumps to is 0x80080000 which is not
2MiB aligned.
Therefore in parallel to the ATF change, this patch set makes the corresponding
changes to u-boot. To maintain backwards compatibility with older ATF builds
(that still use older address of 0x80080000), the patch set also adds a
jump-stub which modifies the execution as follows:
Old ATF -> 0x80080000 -> 0x822000000 (Main domain SPL or kernel image)
jump stub SPL_TEXT_BASE
With the following instructions loaded by the jump-stub:
ADDR | Instruction
0x80080000 | mov x15, CONFIG_SPL_TEXT_BASE (0x822000000)
0x80080004 | br x15
Depends on:
* [PATCH v3] configs: set SPL_TEXT_BASE by default for k3 platforms
https://lore.kernel.org/u-boot/20250415095028.446254-1-ansh...@ti.com/
[1]:
https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/37447
[2]:
"The Image must be placed text_offset bytes from a 2MB aligned base
address anywhere in usable system RAM and called there."
- Documentation/arch/arm64/booting.rst (linux kernel)
Anshul Dalal (4):
spl: Kconfig: k3: set SPL_TEXT_BASE to 0x82200000
mach-k3: add a jump stub to support older ATF builds
binman: k3: add jump-stub to tispl.bin
binman: k3: add jump-stub as loadable
arch/arm/dts/k3-am625-beagleplay-u-boot.dtsi | 2 +-
arch/arm/dts/k3-am625-phycore-som-binman.dtsi | 4 +--
arch/arm/dts/k3-am625-sk-binman.dtsi | 4 +--
.../dts/k3-am625-verdin-wifi-dev-binman.dtsi | 4 +--
arch/arm/dts/k3-am62a-phycore-som-binman.dtsi | 4 +--
arch/arm/dts/k3-am62a-sk-binman.dtsi | 4 +--
arch/arm/dts/k3-am62p-sk-binman.dtsi | 2 +-
arch/arm/dts/k3-am642-phycore-som-binman.dtsi | 8 ++---
arch/arm/dts/k3-am64x-binman.dtsi | 8 ++---
arch/arm/dts/k3-am65-iot2050-boot-image.dtsi | 2 +-
arch/arm/dts/k3-am65x-binman.dtsi | 4 +--
arch/arm/dts/k3-am67a-beagley-ai-u-boot.dtsi | 2 +-
arch/arm/dts/k3-binman.dtsi | 31 +++++++++++++++++++
arch/arm/dts/k3-j7200-binman.dtsi | 4 +--
.../dts/k3-j721e-beagleboneai64-u-boot.dtsi | 2 +-
arch/arm/dts/k3-j721e-binman.dtsi | 4 +--
arch/arm/dts/k3-j721s2-binman.dtsi | 4 +--
arch/arm/dts/k3-j722s-binman.dtsi | 2 +-
arch/arm/dts/k3-j784s4-binman.dtsi | 4 +--
arch/arm/mach-k3/Makefile | 7 +++++
arch/arm/mach-k3/jump_stub.S | 16 ++++++++++
common/spl/Kconfig | 2 +-
22 files changed, 89 insertions(+), 35 deletions(-)
create mode 100644 arch/arm/mach-k3/jump_stub.S
--
2.49.0
