Ulf Hansson <ulf.hansson@xxxxxxxxxx> writes: > On Sun, 26 Jan 2020 at 12:53, Michael Ellerman <mpe@xxxxxxxxxxxxxx> wrote: >> There's an OF helper called of_dma_is_coherent(), which checks if a >> device has a "dma-coherent" property to see if the device is coherent >> for DMA. >> >> But on some platforms devices are coherent by default, and on some >> platforms it's not possible to update existing device trees to add the >> "dma-coherent" property. >> >> So add a Kconfig symbol to allow arch code to tell >> of_dma_is_coherent() that devices are coherent by default, regardless >> of the presence of the property. >> >> Select that symbol on powerpc when NOT_COHERENT_CACHE is not set, ie. >> when the system has a coherent cache. >> >> Fixes: 92ea637edea3 ("of: introduce of_dma_is_coherent() helper") >> Cc: stable@xxxxxxxxxxxxxxx # v3.16+ >> Reported-by: Christian Zigotzky <chzigotzky@xxxxxxxxxxx> >> Tested-by: Christian Zigotzky <chzigotzky@xxxxxxxxxxx> >> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> > > Thanks Michael for helping out fixing and this! The patch looks good to me. > > Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx> Thanks for the review. cheers