Guo Ren <[email protected]> 於 2020年5月31日 週日 上午9:56寫道： > > Hi Greentime, > > Why remove vxrm and xstat ? > > > Appendix B: Calling Convention > > In the RISC-V psABI, the vector registers v0-v31 are all caller-saved. The > > vstart, vl, and vtype CSRs are also caller-saved. > > The vxrm and vxsat fields have thread storage duration. > Hi Guo,
https://github.com/riscv/riscv-v-spec/blob/master/v-spec.adoc#vector-control-and-status-register-vcsr "The vxrm and vxsat separate CSRs can also be accessed via fields in the vector control and status CSR, vcsr." Since vcsr will save all these information, I think it should be ok to save vcsr only. > As spec 0.9 mentioned above, vxrm and vxsat are thread storage duration. > > When timer 's interrupt coming, we still need to save them in context_switch. > > On Tue, May 26, 2020 at 3:03 PM Greentime Hu <[email protected]> wrote: > > > > From: Guo Ren <[email protected]> > > > > Follow the riscv vector spec to add new csr number. > > > > [[email protected]: update the defined value based on new spec and > > remove unused ones] > > Signed-off-by: Greentime Hu <[email protected]> > > Signed-off-by: Guo Ren <[email protected]> > > --- > > arch/riscv/include/asm/csr.h | 16 ++++++++++++++-- > > 1 file changed, 14 insertions(+), 2 deletions(-) > > > > diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h > > index 8e18d2c64399..cc13626c4bbe 100644 > > --- a/arch/riscv/include/asm/csr.h > > +++ b/arch/riscv/include/asm/csr.h > > @@ -24,6 +24,12 @@ > > #define SR_FS_CLEAN _AC(0x00004000, UL) > > #define SR_FS_DIRTY _AC(0x00006000, UL) > > > > +#define SR_VS _AC(0x00000600, UL) /* Vector Status */ > > +#define SR_VS_OFF _AC(0x00000000, UL) > > +#define SR_VS_INITIAL _AC(0x00000200, UL) > > +#define SR_VS_CLEAN _AC(0x00000400, UL) > > +#define SR_VS_DIRTY _AC(0x00000600, UL) > > + > > #define SR_XS _AC(0x00018000, UL) /* Extension Status */ > > #define SR_XS_OFF _AC(0x00000000, UL) > > #define SR_XS_INITIAL _AC(0x00008000, UL) > > @@ -31,9 +37,9 @@ > > #define SR_XS_DIRTY _AC(0x00018000, UL) > > > > #ifndef CONFIG_64BIT > > -#define SR_SD _AC(0x80000000, UL) /* FS/XS dirty */ > > +#define SR_SD _AC(0x80000000, UL) /* FS/VS/XS dirty */ > > #else > > -#define SR_SD _AC(0x8000000000000000, UL) /* FS/XS dirty */ > > +#define SR_SD _AC(0x8000000000000000, UL) /* FS/VS/XS dirty */ > > #endif > > > > /* SATP flags */ > > @@ -114,6 +120,12 @@ > > #define CSR_PMPADDR0 0x3b0 > > #define CSR_MHARTID 0xf14 > > > > +#define CSR_VSTART 0x8 > > +#define CSR_VCSR 0xf > > +#define CSR_VL 0xc20 > > +#define CSR_VTYPE 0xc21 > > +#define CSR_VLENB 0xc22 > > + > > #ifdef CONFIG_RISCV_M_MODE > > # define CSR_STATUS CSR_MSTATUS > > # define CSR_IE CSR_MIE > > -- > > 2.26.2 > > > > > > > -- > Best Regards > Guo Ren > > ML: https://lore.kernel.org/linux-csky/
