Re: [PATCH v3 1/6] target/riscv: Introduce extension implied rules definition

[Alistair Francis]

On Tue, Jun 25, 2024 at 9:47 PM <frank.chang@sifive.com> wrote:
>
> From: Frank Chang <frank.chang@sifive.com>
>
> RISCVCPUImpliedExtsRule is created to store the implied rules.
> 'is_misa' flag is used to distinguish whether the rule is derived
> from the MISA or other extensions.
> 'ext' stores the MISA bit if 'is_misa' is true. Otherwise, it stores
> the offset of the extension defined in RISCVCPUConfig. 'ext' will also
> serve as the key of the hash tables to look up the rule in the following
> commit.
>
> Signed-off-by: Frank Chang <frank.chang@sifive.com>
> Reviewed-by: Jerry Zhang Jian <jerry.zhangjian@sifive.com>
> Tested-by: Max Chou <max.chou@sifive.com>
> Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>

Reviewed-by: Alistair Francis <alistair.francis@wdc.com>

Alistair

> ---
>  target/riscv/cpu.c |  8 ++++++++
>  target/riscv/cpu.h | 23 +++++++++++++++++++++++
>  2 files changed, 31 insertions(+)
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 4760cb2cc1..7b071ade04 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -2250,6 +2250,14 @@ RISCVCPUProfile *riscv_profiles[] = {
>      NULL,
>  };
>
> +RISCVCPUImpliedExtsRule *riscv_misa_ext_implied_rules[] = {
> +    NULL
> +};
> +
> +RISCVCPUImpliedExtsRule *riscv_multi_ext_implied_rules[] = {
> +    NULL
> +};
> +
>  static Property riscv_cpu_properties[] = {
>      DEFINE_PROP_BOOL("debug", RISCVCPU, cfg.debug, true),
>
> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> index 90b8f1b08f..87742047ce 100644
> --- a/target/riscv/cpu.h
> +++ b/target/riscv/cpu.h
> @@ -124,6 +124,29 @@ typedef enum {
>      EXT_STATUS_DIRTY,
>  } RISCVExtStatus;
>
> +typedef struct riscv_cpu_implied_exts_rule {
> +#ifndef CONFIG_USER_ONLY
> +    /*
> +     * Bitmask indicates the rule enabled status for the harts.
> +     * This enhancement is only available in system-mode QEMU,
> +     * as we don't have a good way (e.g. mhartid) to distinguish
> +     * the SMP cores in user-mode QEMU.
> +     */
> +    unsigned long *enabled;
> +#endif
> +    /* True if this is a MISA implied rule. */
> +    bool is_misa;
> +    /* ext is MISA bit if is_misa flag is true, else multi extension offset. 
> */
> +    const uint32_t ext;
> +    const uint32_t implied_misa_exts;
> +    const uint32_t implied_multi_exts[];
> +} RISCVCPUImpliedExtsRule;
> +
> +extern RISCVCPUImpliedExtsRule *riscv_misa_ext_implied_rules[];
> +extern RISCVCPUImpliedExtsRule *riscv_multi_ext_implied_rules[];
> +
> +#define RISCV_IMPLIED_EXTS_RULE_END -1
> +
>  #define MMU_USER_IDX 3
>
>  #define MAX_RISCV_PMPS (16)
> --
> 2.43.2
>
>