Sannum/rpi3 fixups #93
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axel-h
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Jun 28, 2021
| @@ -133,7 +133,7 @@ void main(UNUSED void *arg) | |||
| #endif | |||
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| if (bootloader_dtb) { | |||
| printf(" dtb=%p\n", dtb); | |||
| printf(" dtb=%p\n", bootloader_dtb); | |||
It seems that the 'ldp x0, x1, [sp, #-16]!' syntax used to load the registers stored to the stack before calling the fixup_image_base function does not in fact load the registers as expected (at least on my Raspberry Pi 3B). This causes the dtb address supplied by the bootloader to be lost when elfloader loads the dtb image which is an issue if a dtb is not built into the kernel binary image. In the example usage from arm (https://developer.arm.com/documentation/ 102374/0101/Loads-and-stores---load-pair-and-store-pair) the 'ldp x0, x1, [sp], seL4#16' is used for poping the stack. This also seems to also work as expected on my Raspberry Pi 3B resulting in the dtb address to be loaded as expected in sys_boot.c. Signed-off-by: Viktor Sannum <[email protected]>
For arm builds, check if the bootloader has passed the dtb image address also for binary image builds, similarly to uimages. The Raspberry Pi bootloader for example, is able to both load binary images directly and passes the dtb address to the loaded image as expected. Signed-off-by: Viktor Sannum <[email protected]>
Minor fixup, the dtb variable is always 0 when printed in sys_boot.c as it refers to the the address the dtb is loaded to after load_images has finished loading it from either the bootloader_dtb or cpio archive. Print bootloader_dtb instead, since it contains the address to a valid dtb given by the bootloader or efi. Signed-off-by: Viktor Sannum <[email protected]>
The Raspberry Pi3 has its own definition for configuring the setting for binary images builds for aarch64 only, meaning it cannot be part of the more generic binary_list definition. The 32-bit aarch32 rpi3 builds can also boot from a binary image so there is no actual need for this sepcial handling. Remove it and move the bcm2837/rpi3 match to the binary_list definition instead. Signed-off-by: Viktor Sannum <[email protected]>
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A series of fixups for directly booting seL4 and seL4_test binary images on the Raspberry pi3 in both aarch32 and aarch64 modes as well as succesfully passing the dtb from the bootloader to the elfloader as this is currently not working.
The resulting sel4test-driver-image-arm-bcm2837 binary images should be directly bootable using the common bootloader.bin/start.elf and the following config.txt files:
and
for aarch32 and aarch64 builds respectively.
Currently it seems the kernel_address must be manually configured to match the shoehorn generated IMAGE_START_ADDR which can be found with
as described in elfloader-tool/README.md
This also means that u-boot is not required as per https://docs.sel4.systems/Hardware/Rpi3.html.