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Diffstat (limited to 'docs/user-guide.md')
| -rw-r--r-- | docs/user-guide.md | 73 |
1 files changed, 64 insertions, 9 deletions
diff --git a/docs/user-guide.md b/docs/user-guide.md index 9c17e353..ea10a81e 100644 --- a/docs/user-guide.md +++ b/docs/user-guide.md @@ -10,10 +10,11 @@ Contents : 5. [Building the Trusted Firmware](#5--building-the-trusted-firmware) 6. [Building the rest of the software stack](#6--building-the-rest-of-the-software-stack) 7. [EL3 payloads alternative boot flow](#7--el3-payloads-alternative-boot-flow) -8. [Preparing the images to run on FVP](#8--preparing-the-images-to-run-on-fvp) -9. [Running the software on FVP](#9--running-the-software-on-fvp) -10. [Running the software on Juno](#10--running-the-software-on-juno) -11. [Changes required for booting Linux on FVP in GICv3 mode](#11--changes-required-for-booting-linux-on-fvp-in-gicv3-mode) +8. [Preloaded BL33 alternative boot flow](#8--preloaded-bl33-alternative-boot-flow) +9. [Preparing the images to run on FVP](#9--preparing-the-images-to-run-on-fvp) +10. [Running the software on FVP](#10--running-the-software-on-fvp) +11. [Running the software on Juno](#11--running-the-software-on-juno) +12. [Changes required for booting Linux on FVP in GICv3 mode](#12--changes-required-for-booting-linux-on-fvp-in-gicv3-mode) 1. Introduction @@ -407,6 +408,12 @@ performed. payload. Please refer to the "Booting an EL3 payload" section for more details. +* `BL33_BASE`: This option enables booting a preloaded BL33 image instead of + the normal boot flow. When defined, it must specify the entry point address + for the preloaded BL33 image. This option is incompatible with + `EL3_PAYLOAD_BASE`. If both are defined, `EL3_PAYLOAD_BASE` has priority + over `BL33_BASE`. + * `PL011_GENERIC_UART`: Boolean option to indicate the PL011 driver that the underlying hardware is not a full PL011 UART but a minimally compliant generic UART, which is a subset of the PL011. The driver will not access @@ -973,7 +980,55 @@ Alternatively, the same DS-5 command mentioned in the FVP section above can be used to load the EL3 payload's ELF file over JTAG on Juno. -8. Preparing the images to run on FVP +8. Preloaded BL33 alternative boot flow +---------------------------------------- + +Some platforms have the ability to preload BL33 into memory instead of relying +on Trusted Firmware to load it. This may simplify packaging of the normal world +code and improve performance in a development environment. When secure world +cold boot is complete, Trusted Firmware simply jumps to a BL33 base address +provided at build time. + +For this option to be used, the `BL33_BASE` build option has to be used when +compiling the Trusted Firmware. For example, the following command will create +a FIP without a BL33 and prepare to jump to a BL33 image loaded at address +0x80000000: + + CROSS_COMPILE=<path-to>/bin/aarch64-linux-gnu- \ + make BL33_BASE=0x80000000 PLAT=fvp all fip + +#### Boot of a preloaded bootwrapped kernel image on Base FVP + +The following example uses the AArch64 boot wrapper. This simplifies normal +world booting while also making use of TF features. It can be obtained from its +repository with: + + git clone git://git.kernel.org/pub/scm/linux/kernel/git/mark/boot-wrapper-aarch64.git + +After compiling it, an ELF file is generated. It can be loaded with the +following command: + + <path-to>/FVP_Base_AEMv8A-AEMv8A \ + -C bp.secureflashloader.fname=bl1.bin \ + -C bp.flashloader0.fname=fip.bin \ + -a cluster0.cpu0=<bootwrapped-kernel.elf> \ + --start cluster0.cpu0=0x0 + +The `-a cluster0.cpu0=<bootwrapped-kernel.elf>` option loads the ELF file. It +also sets the PC register to the ELF entry point address, which is not the +desired behaviour, so the `--start cluster0.cpu0=0x0` option forces the PC back +to 0x0 (the BL1 entry point address) on CPU #0. The `BL33_BASE` define used when +compiling the FIP must match the ELF entry point. + +#### Boot of a preloaded bootwrapped kernel image on Juno + +The procedure to obtain and compile the boot wrapper is very similar to the case +of the FVP. Once compiled, the `SPIN_ON_BL1_EXIT=1` loading method explained +above in the EL3 payload boot flow section may be used to load the ELF file over +JTAG on Juno. + + +9. Preparing the images to run on FVP -------------------------------------- Note: This section can be ignored when booting an EL3 payload, as no Flattened @@ -1026,8 +1081,8 @@ Copy the kernel image file `linux/arch/arm64/boot/Image` to the directory from which the FVP is launched. Alternatively a symbolic link may be used. -9. Running the software on FVP -------------------------------- +10. Running the software on FVP +-------------------------------- This version of the ARM Trusted Firmware has been tested on the following ARM FVPs (64-bit versions only). @@ -1326,7 +1381,7 @@ The `bp.variant` parameter corresponds to the build variant field of the detect the legacy VE memory map while configuring the GIC. -10. Running the software on Juno +11. Running the software on Juno --------------------------------- This version of the ARM Trusted Firmware has been tested on Juno r0 and Juno r1. @@ -1408,7 +1463,7 @@ The Juno board should suspend to RAM and then wakeup after 10 seconds due to wakeup interrupt from RTC. -11. Changes required for booting Linux on FVP in GICv3 mode +12. Changes required for booting Linux on FVP in GICv3 mode ------------------------------------------------------------ In case the TF FVP port is built with the build option |