On Tue, 16 Oct 2018 01:19:35 +0000
Stewart Hildebrand <stewart.hildebr...@dornerworks.com> wrote:
Hi,
Stewart, thanks a lot for picking this up!
> On Monday, October 15, 2018 6:05 PM, Philippe Mathieu-Daudé wrote:
> > Hi Stewart,
> >
> > On 15/10/2018 23:26, Stewart Hildebrand wrote:
> > > + /* For the virt board, we write our startup
> > > "bootloader" at the very
> > > + * bottom of RAM, so that bit can't be used for the
> > > image. To avoid
> > > + * overlap in case the image requests to be loaded
> > > at an offset
> > > + * smaller than our bootloader, we increment the
> > > load offset to the
> > > + * next 2MB.
> > > + */
> > > + if (kernel_load_offset < FIXUP_MAX) {
> >
> > I don't understand how this is related to FIXUP_MAX...
>
> You're right, my apologies, it's not directly related.
> write_bootloader() calculates the size of the bootloader like so:
> len = 0;
> while (insns[len].fixup != FIXUP_TERMINATOR) {
> len++;
> }
>
> The size of the bootloader then would be len * sizeof(uint32_t)
>
> It would be nice not to have to repeat that logic in
> load_aarch64_image(). I'll send out a v2 after I take some time to
> wrap my head around it...
I wonder if this could be done much easier, since TEXT_OFFSET must
actually be page aligned. So all we would need is an *upper bound* for
the bootloader size, as long as that is below 4K we wouldn't even loose
anything.
Cheers,
Andre.
> >
> > > + kernel_load_offset += 2 << 20;
> >
> > You can use += 2 * MiB; which is easier to review.
>
> OK, I will include this in v2.
