Hi Peter, On Wed, 11 Dec 2024 at 10:26, Simon Glass <s...@chromium.org> wrote: > > Hi Peter, > > On Wed, 11 Dec 2024 at 09:27, Peter Robinson <pbrobin...@gmail.com> wrote: > > > > > > > > On Mon, 9 Dec 2024 at 19:55, Simon Glass <s...@chromium.org> wrote: > >> > >> Set this option so that all boot images stay within the bottom 512MB of > >> memory. This should allow us to drop the fdt_high and initrd_high > >> options. > > > > > > How does this work for a device with < 256Mb of RAM? There's a number of > > the original RPi series that have 256Mb of RAM and that equates to less > > than that due to reservations for the vendor firmware. > > Looking at boot_relocate_fdt(), this is just a maximum, and lmb is > used to allocate the FDT / cmdline. So this patch shouldn't affect > that. > > But the later patch to move the ramdisk up will cause problems. Based > on the comment, a 256MB (I assume you mean) device can have as little > as 64MB of RAM available to the ARM core, which is not enough to load > a ramdisk from the new start-address of about 90MB. > > I found an old rpi1 which I could hook up to my lab, perhaps. Could > you point me to a distro-image that boots OK on that, ideally with > only 64MB available?
Well I set it up with Raspbian. It seems to boot OK into the kernel. But unfortunately I only have a 512MB device. "When I were a lad, we had hard drives of 20MB and were grateful for it!" > > > > >> > >> Signed-off-by: Simon Glass <s...@chromium.org> > >> Reviewed-by: Tom Rini <tr...@konsulko.com> > >> Suggested-by: Tom Rini <tr...@konsulko.com> > >> --- > >> > >> Changes in v3: > >> - Add to the existing comment block > >> > >> Changes in v2: > >> - Add new patch to set bootm_size > >> > >> board/raspberrypi/rpi/rpi.env | 5 +++++ > >> 1 file changed, 5 insertions(+) > >> > >> diff --git a/board/raspberrypi/rpi/rpi.env b/board/raspberrypi/rpi/rpi.env > >> index 30228285edd..a327fccc77f 100644 > >> --- a/board/raspberrypi/rpi/rpi.env > >> +++ b/board/raspberrypi/rpi/rpi.env > >> @@ -60,7 +60,12 @@ dfu_alt_info+=zImage fat 0 1 > >> * Even with the smallest possible CPU-GPU memory split of the CPU getting > >> * only 64M, the remaining 25M starting at 0x02700000 should allow quite > >> * large initrds before they start colliding with U-Boot. > >> + * > >> + * Limit bootm_size to 512MB so that all boot images stay within the > >> bottom > >> + * 512MB of memory > >> */ > >> +bootm_size=0x20000000 > >> + > >> #ifdef CONFIG_ARM64 > >> fdt_high=ffffffffffffffff > >> initrd_high=ffffffffffffffff > >> -- > >> 2.34.1 > >> Regards, Simon
