Attempting to place device tree immediately after an image in memory can lead to mis-aligned data accesses if that image size is not divisible by the alignment requirements of the architecture.
Data aborts caused by this were observed on a custom Marvel A388 based system, where the image was a uboot FIT file. The total size varies depending on the uboot device tree size, which does not always lead to correct alignment. The minimum alignment specified for ARM [1] and ARM64 [2] linux booting has been used [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/arm/booting.rst#n126 [2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/arm64/booting.rst#n45 Signed-off-by: Reuben Dowle <reuben.do...@4rf.com> --- common/spl/spl_fit.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/common/spl/spl_fit.c b/common/spl/spl_fit.c index 365104f..a8bfd38 100644 --- a/common/spl/spl_fit.c +++ b/common/spl/spl_fit.c @@ -349,9 +349,12 @@ static int spl_fit_append_fdt(struct spl_image_info *spl_image, /* * Use the address following the image as target address for the - * device tree. + * device tree. Load address is aligned to 8 bytes to match the required + * alignment specified for linux arm [1] and arm 64 [2] booting + * [1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/arm/booting.rst#n126 + * [2]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/arm64/booting.rst#n45 */ - image_info.load_addr = spl_image->load_addr + spl_image->size; + image_info.load_addr = ALIGN(spl_image->load_addr + spl_image->size, 8); /* Figure out which device tree the board wants to use */ node = spl_fit_get_image_node(fit, images, FIT_FDT_PROP, index++); -- 2.7.4
