Unverified Commit 0a13a5b8 authored by Alistair Francis's avatar Alistair Francis Committed by Palmer Dabbelt
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target/riscv: Add support for disabling/enabling Counters 



Add support for disabling/enabling the "Counters" extension.

Signed-off-by: default avatarAlistair Francis <alistair.francis@wdc.com>
Reviewed-by: default avatarPalmer Dabbelt <palmer@sifive.com>
Signed-off-by: default avatarPalmer Dabbelt <palmer@sifive.com>
parent c9a73910

target/riscv/cpu.c

+1 −0
Original line number Diff line number Diff line
@@ -440,6 +440,7 @@ static Property riscv_cpu_properties[] = { 
    DEFINE_PROP_BOOL("c", RISCVCPU, cfg.ext_c, true),

    DEFINE_PROP_BOOL("s", RISCVCPU, cfg.ext_s, true),

    DEFINE_PROP_BOOL("u", RISCVCPU, cfg.ext_u, true),

    DEFINE_PROP_BOOL("Counters", RISCVCPU, cfg.ext_counters, true),

    DEFINE_PROP_STRING("priv_spec", RISCVCPU, cfg.priv_spec),

    DEFINE_PROP_BOOL("mmu", RISCVCPU, cfg.mmu, true),

    DEFINE_PROP_BOOL("pmp", RISCVCPU, cfg.pmp, true),

target/riscv/cpu.h

+1 −0
Original line number Diff line number Diff line
@@ -222,6 +222,7 @@ typedef struct RISCVCPU { 
        bool ext_c;

        bool ext_s;

        bool ext_u;

        bool ext_counters;



        char *priv_spec;

        char *user_spec;

target/riscv/csr.c

+12 −5
Original line number Diff line number Diff line
@@ -56,17 +56,24 @@ static int fs(CPURISCVState *env, int csrno) 
static int ctr(CPURISCVState *env, int csrno)

{

#if !defined(CONFIG_USER_ONLY)

    CPUState *cs = env_cpu(env);

    RISCVCPU *cpu = RISCV_CPU(cs);

    uint32_t ctr_en = ~0u;



    if (!cpu->cfg.ext_counters) {

        /* The Counters extensions is not enabled */

        return -1;

    }



    /*

     * The counters are always enabled on newer priv specs, as the CSR has

     * changed from controlling that the counters can be read to controlling

     * that the counters increment.

     * The counters are always enabled at run time on newer priv specs, as the

     * CSR has changed from controlling that the counters can be read to

     * controlling that the counters increment.

     */

    if (env->priv_ver > PRIV_VERSION_1_09_1) {

        return 0;

    }



    uint32_t ctr_en = ~0u;



    if (env->priv < PRV_M) {

        ctr_en &= env->mcounteren;

    }