On Wed, May 01, 2024 at 11:46:07AM +0100, Conor Dooley wrote: > On Fri, Apr 26, 2024 at 02:29:19PM -0700, Charlie Jenkins wrote: > > Separate vendor extensions out into one struct per vendor > > instead of adding vendor extensions onto riscv_isa_ext. > > > > Add a hidden config RISCV_ISA_VENDOR_EXT to conditionally include this > > code. > > > > The xtheadvector vendor extension is added using these changes. > > This mostly looks good to me, thanks for the updates. There's one thing > that I think is wrong, but I need to test and will get back to you on... > > > Signed-off-by: Charlie Jenkins <charlie@xxxxxxxxxxxx> > > --- > > arch/riscv/Kconfig | 2 + > > arch/riscv/Kconfig.vendor | 19 ++++++ > > arch/riscv/include/asm/cpufeature.h | 18 ++++++ > > arch/riscv/include/asm/vendor_extensions.h | 26 ++++++++ > > arch/riscv/include/asm/vendor_extensions/thead.h | 19 ++++++ > > arch/riscv/kernel/Makefile | 2 + > > arch/riscv/kernel/cpufeature.c | 77 ++++++++++++++++++------ > > arch/riscv/kernel/vendor_extensions.c | 18 ++++++ > > arch/riscv/kernel/vendor_extensions/Makefile | 3 + > > arch/riscv/kernel/vendor_extensions/thead.c | 36 +++++++++++ > > 10 files changed, 200 insertions(+), 20 deletions(-) > > > > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > > index be09c8836d56..fec86fba3acd 100644 > > --- a/arch/riscv/Kconfig > > +++ b/arch/riscv/Kconfig > > @@ -759,6 +759,8 @@ config RISCV_EFFICIENT_UNALIGNED_ACCESS > > > > endchoice > > > > +source "arch/riscv/Kconfig.vendor" > > + > > endmenu # "Platform type" > > > > menu "Kernel features" > > diff --git a/arch/riscv/Kconfig.vendor b/arch/riscv/Kconfig.vendor > > new file mode 100644 > > index 000000000000..4fc86810af1d > > --- /dev/null > > +++ b/arch/riscv/Kconfig.vendor > > @@ -0,0 +1,19 @@ > > +menu "Vendor extensions" > > + > > +config RISCV_ISA_VENDOR_EXT > > + bool > > + > > +menu "T-Head" > > +config RISCV_ISA_VENDOR_EXT_THEAD > > + bool "T-Head vendor extension support" > > + select RISCV_ISA_VENDOR_EXT > > + default y > > + help > > + Say N here if you want to disable all T-Head vendor extension > > + support. This will cause any T-Head vendor extensions that are > > + requested to be ignored. > > What does "requested to be ignored" mean to a punter configuring a > kernel? I'd expect this to be something like: > > "Say N here to disable detection of and support for all T-Head vendor > extensions. Without this option enabled, T-Head vendor extensions will > not be detected at boot and their presence not reported to userspace." Sounds great I will change to that. - Charlie > > In general, I'd expect something that needs some support in the kernel > (like vector) to function to have a dedicated option, but the likes of > their Zba variant could be detected and reported via hwprobe et al > once RISCV_ISA_VENDOR_EXT_THEAD is enabled. > > Cheers, > Conor.
