Re: Booting the FreeBSD kernel as an zImage file needs a patch upgrade ?.

[Warner Losh <imp@xxxxxxxxxx>]

So kernel.bin is expected to be loaded, by u-boot, using the 'load' command at a specific address. On arm, this can be any 2MB boundary. Once it is loaded, you jump to the _start address woth the 'go' command. The kernel.bin file doesn't have symbols, so you'll need to see where _start winds up at.

So, let's say that the memory starts at 0x80000000 and _start is something like 0xc0000020 when you nm kernel | grep start you'd do something like:

u-boot> load kernel.bin 0x80000000

u-boot> go 0x80000020

Though I'm unsure what u-boot will read the kernel.bin from. Maybe xen can load it at a specific spot (and maybe your hunch is right that you can replace uboot with this binary... ive never xen booted like this so i don't know if you need the low level steps uboot preforms to be done or not). I suspect that it might and my info is just for raw hardware...

Warner

On Mon, Jan 1, 2024, 12:47 PM Mario Marietto <marietto2008@xxxxxxxxx> wrote:

Thanks Warner. But the kernel.bin file should be used instead of the u-boot file as bootloader ? and will it work as expected ? even if i have patched the elliott code with the wrong patch ? thats because I havent a working patch to use that can allow the frrebsd code to be threated as an zImage file ?

Il lun 1 gen 2024, 20:39 Warner Losh <imp@xxxxxxxxxx> ha scritto:

Julien said that I could try to revert the commiting removing the step
to create kernel.bin,but I don't know what it means,I don't know how
to do that and I haven't found anyone who wants to explain to  me how
to do it. And I'm not sure that it will be enough.

You need to add WITH_KERNEL_BIN for it to generate a kernel.bin file.

We turned that off by default since most people don't need/can't use that

file.

Warner