On 14/02/23, Ying-Chun Liu (PaulLiu) wrote:
From: Marc Zyngier maz@kernel.org
In the add_map() function, for each level it populates, it iterates from the root of the PT tree, making it ineficient if a mapping needs to occur past level 1.
Instead, replace it with a recursive (and much simpler) algorithm that keeps the complexity as low as possible. With this, mapping 512GB at level 2 goes from several seconds down to not measurable on an A55 machine.
We keep the block mappings at level 1 for now though.
Signed-off-by: Marc Zyngier maz@kernel.org Signed-off-by: Pierre-Clément Tosi ptosi@google.com [ Paul: pick from the Android tree. Fixup Pierre's commit. Rebase to the upstream ] Signed-off-by: Ying-Chun Liu (PaulLiu) paul.liu@linaro.org Cc: Tom Rini trini@konsulko.com Link: https://android.googlesource.com/platform/external/u-boot/+/96ad729cf4cab53b... Link: https://android.googlesource.com/platform/external/u-boot/+/6be9330601d81545...
Hello Marc,
this patch somehow broke the boot of my imx8qm board. I run into this issue:
U-Boot 2023.07-rc6-00004-g5527698481 (Aug 01 2023 - 10:10:52 +0200)
Model: Advantech iMX8QM DMSSE20 Board: DMS-SE20A1 8GB Build: SCFW 549b1e18, SECO-FW c9de51c0, ATF 5782363 Boot: USB DRAM: 8 GiB "Error" handler, esr 0xbf000000 elr: 0000000080020938 lr : 00000000800209c8 (reloc) elr: 00000000ffecf938 lr : 00000000ffecf9c8 x0 : 0000000000000001 x1 : 0000000060000000 x2 : 0000000010000000 x3 : 0000000000000002 x4 : 0000000040000000 x5 : 0060000000000401 x6 : 0000000000000800 x7 : 00000000fff44a60 x8 : 0068000000000481 x9 : 0000000000000008 x10: 000000000a200023 x11: 0000000000000002 x12: 0000000000000002 x13: 0000000080095a00 x14: 00000000ffffffff x15: 00000000ffecfd2c x16: 000000008005454c x17: 0000000000000000 x18: 00000000fd6afd50 x19: 000000000fe00000 x20: 0000000000000000 x21: 0060000000000401 x22: 0000000060200000 x23: 0000000000200000 x24: 0000000040000808 x25: 00000000001fffff x26: 0000000000000003 x27: 0000000060200000 x28: 0000000000000002 x29: 00000000fd6ab110
Code: a94573fb a8c67bfd d65f03c0 b9418a40 (8a160334) Resetting CPU ...
resetting ... SCI reboot request............................................................................................................................................................................................................................
After some bisecting this patch poped up:
41e2787f5ec4249cb2e77a3ebd3c49035e3c6535 is the first bad commit arm64: Reduce add_map() complexity
After I reverted everything on top of this patch its booting again with v2023.07
commit c1da6fdb5c239b432440721772d993e63cfdeb20 armv8: enable HAFDBS for other ELx when FEAT_HAFDBS is present
commit 836b8d4b205d2175b57cb9ef271e638b0c116e89 arm64: Use level-2 for largest block mappings when FEAT_HAFDBS is present
commit 6cdf6b7a340db4ddd008516181de7e08e3f8c213 arm64: Use FEAT_HAFDBS to track dirty pages when available
Do you have any idea whats going on here?
Best Regards,
Oliver