Re: [PATCH] target/riscv: csr: Implement mconfigptr CSR

[Bin Meng]

On Sun, Oct 3, 2021 at 7:29 PM Rahul Pathak <rpathak@ventanamicro.com> wrote:
>
> mconfigptr is an mandatory CSR as per the priv spec.

%s/an/a

as per the priv spec v1.12

> This csr holds the physical address of the configuration
> data structure if this data structure is implemented
> Its an readonly csr set to zero making configuration
> data structure not supported.
>
> Signed-off-by: Rahul Pathak <rpathak@ventanamicro.com>
> ---
>  target/riscv/cpu_bits.h | 1 +
>  target/riscv/csr.c      | 1 +
>  2 files changed, 2 insertions(+)
>
> diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> index 999187a9ee..5dc4729ed5 100644
> --- a/target/riscv/cpu_bits.h
> +++ b/target/riscv/cpu_bits.h
> @@ -140,6 +140,7 @@
>  #define CSR_MARCHID         0xf12
>  #define CSR_MIMPID          0xf13
>  #define CSR_MHARTID         0xf14
> +#define CSR_MCONFIGPTR      0xf15
>
>  /* Machine Trap Setup */
>  #define CSR_MSTATUS         0x300
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index 23fbbd3216..2182943f54 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -1549,6 +1549,7 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
>      [CSR_MARCHID]   = { "marchid",   any,   read_zero    },
>      [CSR_MIMPID]    = { "mimpid",    any,   read_zero    },
>      [CSR_MHARTID]   = { "mhartid",   any,   read_mhartid },
> +    [CSR_MCONFIGPTR] = {"mconfigptr", any,  read_zero    },

Not any, as we need to check the priv version >= 1.12

>
>      /* Machine Trap Setup */
>      [CSR_MSTATUS]     = { "mstatus",    any,   read_mstatus,     
> write_mstatus     },
> --

Regards,
Bin