[PATCH v5 1/4] mm: modify pte format for Svnapot

[Conor Dooley]

On Tue, Oct 04, 2022 at 07:00:27PM +0200, Andrew Jones wrote:
> On Mon, Oct 03, 2022 at 09:47:18PM +0800, panqinglin2020 at iscas.ac.cn wrote:
> > From: Qinglin Pan <panqinglin2020 at iscas.ac.cn>
> > 
> > This commit adds two erratas to enable/disable svnapot support, patches
> > code dynamicly when "svnapot" is in the "riscv,isa" field of fdt and
> > SVNAPOT compile option is set. It will influence the behavior of
> > has_svnapot function and pte_pfn function. All code dependent on svnapot
> > should make sure that has_svnapot return true firstly.
> > 
> > Also, this commit modifies PTE definition for Svnapot, and creates some
> > functions in pgtable.h to mark a PTE as napot and check if it is a Svnapot
> > PTE. Until now, only 64KB napot size is supported in draft spec, so some
> > macros has only 64KB version.

> > diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> > index 0be8a2403212..d2a61122c595 100644
> > --- a/arch/riscv/kernel/cpu.c
> > +++ b/arch/riscv/kernel/cpu.c
> > @@ -96,6 +96,7 @@ static struct riscv_isa_ext_data isa_ext_arr[] = {
> >  	__RISCV_ISA_EXT_DATA(zicbom, RISCV_ISA_EXT_ZICBOM),
> >  	__RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE),
> >  	__RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC),
> > +	__RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT),
> 
> If we want to do a separate isa extension alphabetizing patch, then this
> array would be a good one to do since it's the output order.

Just quickly jumping in to say that Palmer's already sent one:
https://lore.kernel.org/all/20220920204518.10988-1-palmer@rivosinc.com/

Thanks,
Conor.