On 13:00-20250416, Anshul Dalal wrote:
> 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
How about u-boot documentation?
>
> 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
>
--
Regards,
Nishanth Menon
Key (0xDDB5849D1736249D) / Fingerprint: F8A2 8693 54EB 8232 17A3 1A34 DDB5
849D 1736 249D
