4c117f6c49
This patch adds support for booting EL3 payloads on CSS platforms, for example Juno. In this scenario, the Trusted Firmware follows its normal boot flow up to the point where it would normally pass control to the BL31 image. At this point, it jumps to the EL3 payload entry point address instead. Before handing over to the EL3 payload, the data SCP writes for AP at the beginning of the Trusted SRAM is restored, i.e. we zero the first 128 bytes and restore the SCP Boot configuration. The latter is saved before transferring the BL30 image to SCP and is restored just after the transfer (in BL2). The goal is to make it appear that the EL3 payload is the first piece of software to run on the target. The BL31 entrypoint info structure is updated to make the primary CPU jump to the EL3 payload instead of the BL31 image. The mailbox is populated with the EL3 payload entrypoint address, which releases the secondary CPUs out of their holding pen (if the SCP has powered them on). The arm_program_trusted_mailbox() function has been exported for this purpose. The TZC-400 configuration in BL2 is simplified: it grants secure access only to the whole DRAM. Other security initialization is unchanged. This alternative boot flow is disabled by default. A new build option EL3_PAYLOAD_BASE has been introduced to enable it and provide the EL3 payload's entry point address. The build system has been modified such that BL31 and BL33 are not compiled and/or not put in the FIP in this case, as those images are not used in this boot flow. Change-Id: Id2e26fa57988bbc32323a0effd022ab42f5b5077 |
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| .. | ||
| aarch64 | ||
| bl2.ld.S | ||
| bl2.mk | ||
| bl2_main.c | ||
| bl2_private.h | ||