Commit Graph

2 Commits

Author SHA1 Message Date
Rafał Miłecki
28d641be43 bcm53xx: update copy of ASM entry flushing whole D-cache
Previous version was based on code from kernel 2.6.22 with Broadcom two
trivial modifications. This updates the copy to the version from current
kernel and refreshes the patch.

This was tested for regressions on Netgear R6250 (BCM4708A0), D-Link
DIR-885L (BCM4709C0) and Tenda AC9 (BCM47189B0).

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2016-08-19 12:47:58 +02:00
Rafał Miłecki
5e885c09c6 bcm53xx: switch back to standalone ASM entry flushing cache
Over a year ago in a commit ac96a1665a ("bcm53xx: update Disable MMU
and Dcache during decompression") we switched to Florian's patch for
workarounding CFE bug. The main difference was using a part of existing
__armv7_mmu_cache_flush instead of implementing flushing separately.

This worked well for Northstar devices but doesn't work for BCM53573 as
these devices simply don't start booting with Florian's patch. It's
because of the ldmfd ASM instruction in the __armv7_mmu_cache_flush.

So this commit switches back to using standalone implementation. This
time instead of copying Broadcom's copy of cache-v7.S, we just make a
copy of the original file on our own. Unfortunately we can't cross-dir
compile cache-v7.S from ../../mm/ as that one also adds __INITDATA with
define_cache_functions v7 which would just trigger
> Error: unrecognized/unsupported machine ID (r1 = 0x0000007f).

The only real change Broadcom did in copied .S file was modifying mcr
instruction to use c6 instead of c14. It isn't clear to me if we really
need it, but let's use it for now.

By the way we also update commit message of the
[PATCH] ARM: BCM5301X: Disable MMU and Dcache during decompression

This makes kernel booting on BCM53573 successfully.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2016-08-19 11:38:44 +02:00