commit edc0378eee upstream.
There are some Loongson64 systems come with broken coherent DMA
support, firmware will set a bit in boot_param and pass nocoherentio
in cmdline.
However nonconherent support was missed out when spin off Loongson-2EF
form Loongson64, and that boot_param change never made itself into
upstream.
Support DMA noncoherent properly to get those systems working.
Cc: stable@vger.kernel.org
Fixes: 71e2f4dd5a ("MIPS: Fork loongson2ef from loongson64")
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
b4e440cf60