On Fri, Jul 01, 2016 at 04:48:39PM +0200, Stefan Müller-Klieser wrote: > According to the kernel documentation it is recommended to place the > compressed image between 32 MiB and 128 MiB. The DTB and initrd should > be placed above 128 MiB. We will follow the recommendation as long as we > have enough RAM. If this is not the case, we fall back to the scheme. > This change is required because of the ARM default kernel config changes > regarding RODATA layout, which lead to an increased compression factor > of the kernel image. > This should be regarded as an intermediate solution until there is a > mechanism for the kernel image to report the decompressed layout > requirements to the bootloader. > > Signed-off-by: Stefan Müller-Klieser <s.mueller-klieser@xxxxxxxxx> > --- > arch/arm/lib/bootm.c | 18 +++++++++++++++--- > 1 file changed, 15 insertions(+), 3 deletions(-) Applied, thanks. Let's hope we don't have to revisit this too soon. Sascha > > diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c > index 803aa94..be1259b 100644 > --- a/arch/arm/lib/bootm.c > +++ b/arch/arm/lib/bootm.c > @@ -81,10 +81,15 @@ static int get_kernel_addresses(size_t image_size, > return ret; > > /* > - * We don't know the exact decompressed size so just use a conservative > - * default of 4 times the size of the compressed image. > + * The kernel documentation "Documentation/arm/Booting" advises > + * to place the compressed image outside of the lowest 32 MiB to > + * avoid relocation. We should do this if we have at least 64 MiB > + * of ram. If we have less space, we assume a maximum > + * compression factor of 5. > */ > - image_decomp_size = PAGE_ALIGN(image_size * 4); > + image_decomp_size = PAGE_ALIGN(image_size * 5); > + if (mem_size >= SZ_64M) > + image_decomp_size = max(image_decomp_size, SZ_32M); > > /* > * By default put oftree/initrd close behind compressed kernel image to > @@ -113,6 +118,13 @@ static int get_kernel_addresses(size_t image_size, > > *mem_free = PAGE_ALIGN(*load_address + image_size + spacing); > > + /* > + * Place oftree/initrd outside of the first 128 MiB, if we have space > + * for it. This avoids potential conflicts with the kernel decompressor. > + */ > + if (mem_size > SZ_256M) > + *mem_free = max(*mem_free, mem_start + SZ_128M); > + > return 0; > } > > -- > 1.9.1 > > > _______________________________________________ > barebox mailing list > barebox@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/barebox -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
