lkml.org 
[lkml]   [2020]   [May]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [RFC PATCH v4 05/13] riscv: Add new csr defines related to vector extension
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.

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 <greentime.hu@sifive.com> wrote:
>
> From: Guo Ren <guoren@linux.alibaba.com>
>
> Follow the riscv vector spec to add new csr number.
>
> [greentime.hu@sifive.com: update the defined value based on new spec and
> remove unused ones]
> Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
> Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
> ---
> 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/

\
 
 \ /
  Last update: 2020-05-31 03:57    [W:0.225 / U:4.680 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site