> +config PPC_DAWR
> + bool
> + default n
"default n" is the default default. No need to write this line.
> +++ b/arch/powerpc/kernel/dawr.c
> @@ -0,0 +1,100 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +//
> +// DAWR infrastructure
> +//
> +// Copyright 2019, Michael Neuling, IBM Corporation.
Normal top of file header should be /* */, //-style comments are only
for the actual SPDX heder line.
> + /* Send error to user if they hypervisor won't allow us to write DAWR */
> + if ((!dawr_force_enable) &&
> + (firmware_has_feature(FW_FEATURE_LPAR)) &&
> + (set_dawr(&null_brk) != H_SUCCESS))
None of the three inner brace sets here are required, and the code
becomes much easier to read without them.
> + return -1;
What about returning a proper error code?
> +static int __init dawr_force_setup(void)
> +{
> + dawr_force_enable = false;
This variable already is initialized to alse by default, so this line
is not required.
> + if (PVR_VER(mfspr(SPRN_PVR)) == PVR_POWER9) {
> + /* Turn DAWR off by default, but allow admin to turn it on */
> + dawr_force_enable = false;
.. and neither is this one.
