Hi,
I don't believe there is a way to "disable" NS EL2 if HW implements it. Although you can instruct TF-A to hand over (exception return) from BL31 to BL33 at NS EL1 (rather than NS EL2 by default). For Arm platforms you may override arm_get_spsr_for_bl33_entry: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/plat/arm/co...
This is called from two different sites (arm_bl2_handle_post_image_load, arm_bl31_early_platform_setup). I assume you may also tweak the bl2 load parameters like below (but that may be overridden by arm_get_spsr_for_bl33_entry) https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/plat/arm/co...
/* Fill BL33 related information */ { .image_id = BL33_IMAGE_ID, [...] .ep_info.pc = PLAT_ARM_NS_IMAGE_BASE, .ep_info.spsr = SPSR_64(MODE_EL1, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS),
Regards, Olivier.
________________________________________ From: TF-A tf-a-bounces@lists.trustedfirmware.org on behalf of IS20 Boaz Baron via TF-A tf-a@lists.trustedfirmware.org Sent: 14 September 2021 09:28 To: tf-a@lists.trustedfirmware.org Subject: [TF-A] Disable the EL2 hypervisor mode
Hi all, I have a little question, how can I disable the hypervisor mode so EL2 will be just bridge to EL1 ns? (I mean without touching common ARM code only the platform-oriented code)
Thanks, Boaz.
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