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[PATCH v10 05/12] target/riscv: Implement mcountinhibit CSR

Atish Patra posted 12 patches 3 years, 7 months ago
Maintainers: Palmer Dabbelt <palmer@dabbelt.com>, Alistair Francis <alistair.francis@wdc.com>, Bin Meng <bin.meng@windriver.com>
There is a newer version of this series
[PATCH v10 05/12] target/riscv: Implement mcountinhibit CSR
Posted by Atish Patra 3 years, 7 months ago 
From: Atish Patra <atish.patra@wdc.com>

As per the privilege specification v1.11, mcountinhibit allows to start/stop
a pmu counter selectively.

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
---
 target/riscv/cpu.h      |  2 ++
 target/riscv/cpu_bits.h |  4 ++++
 target/riscv/csr.c      | 25 +++++++++++++++++++++++++
 target/riscv/machine.c  |  1 +
 4 files changed, 32 insertions(+)

diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
index ffee54ea5c27..0a916db9f614 100644
--- a/target/riscv/cpu.h
+++ b/target/riscv/cpu.h
@@ -275,6 +275,8 @@ struct CPUArchState {
     target_ulong scounteren;
     target_ulong mcounteren;
 
+    target_ulong mcountinhibit;
+
     target_ulong sscratch;
     target_ulong mscratch;
 
diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
index 4d04b20d064e..b3f7fa713000 100644
--- a/target/riscv/cpu_bits.h
+++ b/target/riscv/cpu_bits.h
@@ -367,6 +367,10 @@
 #define CSR_MHPMCOUNTER29   0xb1d
 #define CSR_MHPMCOUNTER30   0xb1e
 #define CSR_MHPMCOUNTER31   0xb1f
+
+/* Machine counter-inhibit register */
+#define CSR_MCOUNTINHIBIT   0x320
+
 #define CSR_MHPMEVENT3      0x323
 #define CSR_MHPMEVENT4      0x324
 #define CSR_MHPMEVENT5      0x325
diff --git a/target/riscv/csr.c b/target/riscv/csr.c
index b4a8e15f498f..94d39a4ce1c5 100644
--- a/target/riscv/csr.c
+++ b/target/riscv/csr.c
@@ -1475,6 +1475,28 @@ static RISCVException write_mtvec(CPURISCVState *env, int csrno,
     return RISCV_EXCP_NONE;
 }
 
+static RISCVException read_mcountinhibit(CPURISCVState *env, int csrno,
+                                         target_ulong *val)
+{
+    if (env->priv_ver < PRIV_VERSION_1_11_0) {
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
+    *val = env->mcountinhibit;
+    return RISCV_EXCP_NONE;
+}
+
+static RISCVException write_mcountinhibit(CPURISCVState *env, int csrno,
+                                          target_ulong val)
+{
+    if (env->priv_ver < PRIV_VERSION_1_11_0) {
+        return RISCV_EXCP_ILLEGAL_INST;
+    }
+
+    env->mcountinhibit = val;
+    return RISCV_EXCP_NONE;
+}
+
 static RISCVException read_mcounteren(CPURISCVState *env, int csrno,
                                       target_ulong *val)
 {
@@ -3745,6 +3767,9 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
     [CSR_MHPMCOUNTER30]  = { "mhpmcounter30",  mctr,   read_zero },
     [CSR_MHPMCOUNTER31]  = { "mhpmcounter31",  mctr,   read_zero },
 
+    [CSR_MCOUNTINHIBIT]  = { "mcountinhibit",   any,    read_mcountinhibit,
+                                                       write_mcountinhibit },
+
     [CSR_MHPMEVENT3]     = { "mhpmevent3",     any,    read_zero },
     [CSR_MHPMEVENT4]     = { "mhpmevent4",     any,    read_zero },
     [CSR_MHPMEVENT5]     = { "mhpmevent5",     any,    read_zero },
diff --git a/target/riscv/machine.c b/target/riscv/machine.c
index 2a437b29a1ce..87cd55bfd3a7 100644
--- a/target/riscv/machine.c
+++ b/target/riscv/machine.c
@@ -330,6 +330,7 @@ const VMStateDescription vmstate_riscv_cpu = {
         VMSTATE_UINTTL(env.siselect, RISCVCPU),
         VMSTATE_UINTTL(env.scounteren, RISCVCPU),
         VMSTATE_UINTTL(env.mcounteren, RISCVCPU),
+        VMSTATE_UINTTL(env.mcountinhibit, RISCVCPU),
         VMSTATE_UINTTL(env.sscratch, RISCVCPU),
         VMSTATE_UINTTL(env.mscratch, RISCVCPU),
         VMSTATE_UINT64(env.mfromhost, RISCVCPU),
-- 
2.25.1
Re: [PATCH v10 05/12] target/riscv: Implement mcountinhibit CSR
Posted by Weiwei Li 3 years, 7 months ago 
在 2022/6/21 上午7:15, Atish Patra 写道:
> From: Atish Patra <atish.patra@wdc.com>
>
> As per the privilege specification v1.11, mcountinhibit allows to start/stop
> a pmu counter selectively.
>
> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
> Signed-off-by: Atish Patra <atish.patra@wdc.com>
> Signed-off-by: Atish Patra <atishp@rivosinc.com>
> ---
>   target/riscv/cpu.h      |  2 ++
>   target/riscv/cpu_bits.h |  4 ++++
>   target/riscv/csr.c      | 25 +++++++++++++++++++++++++
>   target/riscv/machine.c  |  1 +
>   4 files changed, 32 insertions(+)
>
> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> index ffee54ea5c27..0a916db9f614 100644
> --- a/target/riscv/cpu.h
> +++ b/target/riscv/cpu.h
> @@ -275,6 +275,8 @@ struct CPUArchState {
>       target_ulong scounteren;
>       target_ulong mcounteren;
>   
> +    target_ulong mcountinhibit;
> +
>       target_ulong sscratch;
>       target_ulong mscratch;
>   
> diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> index 4d04b20d064e..b3f7fa713000 100644
> --- a/target/riscv/cpu_bits.h
> +++ b/target/riscv/cpu_bits.h
> @@ -367,6 +367,10 @@
>   #define CSR_MHPMCOUNTER29   0xb1d
>   #define CSR_MHPMCOUNTER30   0xb1e
>   #define CSR_MHPMCOUNTER31   0xb1f
> +
> +/* Machine counter-inhibit register */
> +#define CSR_MCOUNTINHIBIT   0x320
> +
>   #define CSR_MHPMEVENT3      0x323
>   #define CSR_MHPMEVENT4      0x324
>   #define CSR_MHPMEVENT5      0x325
> diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> index b4a8e15f498f..94d39a4ce1c5 100644
> --- a/target/riscv/csr.c
> +++ b/target/riscv/csr.c
> @@ -1475,6 +1475,28 @@ static RISCVException write_mtvec(CPURISCVState *env, int csrno,
>       return RISCV_EXCP_NONE;
>   }
>   
> +static RISCVException read_mcountinhibit(CPURISCVState *env, int csrno,
> +                                         target_ulong *val)
> +{
> +    if (env->priv_ver < PRIV_VERSION_1_11_0) {
> +        return RISCV_EXCP_ILLEGAL_INST;
> +    }
> +

This seems can be done by add  .min_priv_ver=PRIV_VERSION_1_11_0 in 
csr_ops table.

Regards,

Weiwei Li

> +    *val = env->mcountinhibit;
> +    return RISCV_EXCP_NONE;
> +}
> +
> +static RISCVException write_mcountinhibit(CPURISCVState *env, int csrno,
> +                                          target_ulong val)
> +{
> +    if (env->priv_ver < PRIV_VERSION_1_11_0) {
> +        return RISCV_EXCP_ILLEGAL_INST;
> +    }
> +
> +    env->mcountinhibit = val;
> +    return RISCV_EXCP_NONE;
> +}
> +
>   static RISCVException read_mcounteren(CPURISCVState *env, int csrno,
>                                         target_ulong *val)
>   {
> @@ -3745,6 +3767,9 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
>       [CSR_MHPMCOUNTER30]  = { "mhpmcounter30",  mctr,   read_zero },
>       [CSR_MHPMCOUNTER31]  = { "mhpmcounter31",  mctr,   read_zero },
>   
> +    [CSR_MCOUNTINHIBIT]  = { "mcountinhibit",   any,    read_mcountinhibit,
> +                                                       write_mcountinhibit },
> +
>       [CSR_MHPMEVENT3]     = { "mhpmevent3",     any,    read_zero },
>       [CSR_MHPMEVENT4]     = { "mhpmevent4",     any,    read_zero },
>       [CSR_MHPMEVENT5]     = { "mhpmevent5",     any,    read_zero },
> diff --git a/target/riscv/machine.c b/target/riscv/machine.c
> index 2a437b29a1ce..87cd55bfd3a7 100644
> --- a/target/riscv/machine.c
> +++ b/target/riscv/machine.c
> @@ -330,6 +330,7 @@ const VMStateDescription vmstate_riscv_cpu = {
>           VMSTATE_UINTTL(env.siselect, RISCVCPU),
>           VMSTATE_UINTTL(env.scounteren, RISCVCPU),
>           VMSTATE_UINTTL(env.mcounteren, RISCVCPU),
> +        VMSTATE_UINTTL(env.mcountinhibit, RISCVCPU),
>           VMSTATE_UINTTL(env.sscratch, RISCVCPU),
>           VMSTATE_UINTTL(env.mscratch, RISCVCPU),
>           VMSTATE_UINT64(env.mfromhost, RISCVCPU),
Re: [PATCH v10 05/12] target/riscv: Implement mcountinhibit CSR
Posted by Atish Kumar Patra 3 years, 7 months ago 
On Mon, Jul 4, 2022 at 8:31 AM Weiwei Li <liweiwei@iscas.ac.cn> wrote:
>
>
> 在 2022/6/21 上午7:15, Atish Patra 写道:
> > From: Atish Patra <atish.patra@wdc.com>
> >
> > As per the privilege specification v1.11, mcountinhibit allows to start/stop
> > a pmu counter selectively.
> >
> > Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
> > Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
> > Signed-off-by: Atish Patra <atish.patra@wdc.com>
> > Signed-off-by: Atish Patra <atishp@rivosinc.com>
> > ---
> >   target/riscv/cpu.h      |  2 ++
> >   target/riscv/cpu_bits.h |  4 ++++
> >   target/riscv/csr.c      | 25 +++++++++++++++++++++++++
> >   target/riscv/machine.c  |  1 +
> >   4 files changed, 32 insertions(+)
> >
> > diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> > index ffee54ea5c27..0a916db9f614 100644
> > --- a/target/riscv/cpu.h
> > +++ b/target/riscv/cpu.h
> > @@ -275,6 +275,8 @@ struct CPUArchState {
> >       target_ulong scounteren;
> >       target_ulong mcounteren;
> >
> > +    target_ulong mcountinhibit;
> > +
> >       target_ulong sscratch;
> >       target_ulong mscratch;
> >
> > diff --git a/target/riscv/cpu_bits.h b/target/riscv/cpu_bits.h
> > index 4d04b20d064e..b3f7fa713000 100644
> > --- a/target/riscv/cpu_bits.h
> > +++ b/target/riscv/cpu_bits.h
> > @@ -367,6 +367,10 @@
> >   #define CSR_MHPMCOUNTER29   0xb1d
> >   #define CSR_MHPMCOUNTER30   0xb1e
> >   #define CSR_MHPMCOUNTER31   0xb1f
> > +
> > +/* Machine counter-inhibit register */
> > +#define CSR_MCOUNTINHIBIT   0x320
> > +
> >   #define CSR_MHPMEVENT3      0x323
> >   #define CSR_MHPMEVENT4      0x324
> >   #define CSR_MHPMEVENT5      0x325
> > diff --git a/target/riscv/csr.c b/target/riscv/csr.c
> > index b4a8e15f498f..94d39a4ce1c5 100644
> > --- a/target/riscv/csr.c
> > +++ b/target/riscv/csr.c
> > @@ -1475,6 +1475,28 @@ static RISCVException write_mtvec(CPURISCVState *env, int csrno,
> >       return RISCV_EXCP_NONE;
> >   }
> >
> > +static RISCVException read_mcountinhibit(CPURISCVState *env, int csrno,
> > +                                         target_ulong *val)
> > +{
> > +    if (env->priv_ver < PRIV_VERSION_1_11_0) {
> > +        return RISCV_EXCP_ILLEGAL_INST;
> > +    }
> > +
>
> This seems can be done by add  .min_priv_ver=PRIV_VERSION_1_11_0 in
> csr_ops table.
>

Yes. This can be dropped from both read/write_mcountihibit with min_priv_ver.
Thanks.

> Regards,
>
> Weiwei Li
>
> > +    *val = env->mcountinhibit;
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> > +static RISCVException write_mcountinhibit(CPURISCVState *env, int csrno,
> > +                                          target_ulong val)
> > +{
> > +    if (env->priv_ver < PRIV_VERSION_1_11_0) {
> > +        return RISCV_EXCP_ILLEGAL_INST;
> > +    }
> > +
> > +    env->mcountinhibit = val;
> > +    return RISCV_EXCP_NONE;
> > +}
> > +
> >   static RISCVException read_mcounteren(CPURISCVState *env, int csrno,
> >                                         target_ulong *val)
> >   {
> > @@ -3745,6 +3767,9 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = {
> >       [CSR_MHPMCOUNTER30]  = { "mhpmcounter30",  mctr,   read_zero },
> >       [CSR_MHPMCOUNTER31]  = { "mhpmcounter31",  mctr,   read_zero },
> >
> > +    [CSR_MCOUNTINHIBIT]  = { "mcountinhibit",   any,    read_mcountinhibit,
> > +                                                       write_mcountinhibit },
> > +
> >       [CSR_MHPMEVENT3]     = { "mhpmevent3",     any,    read_zero },
> >       [CSR_MHPMEVENT4]     = { "mhpmevent4",     any,    read_zero },
> >       [CSR_MHPMEVENT5]     = { "mhpmevent5",     any,    read_zero },
> > diff --git a/target/riscv/machine.c b/target/riscv/machine.c
> > index 2a437b29a1ce..87cd55bfd3a7 100644
> > --- a/target/riscv/machine.c
> > +++ b/target/riscv/machine.c
> > @@ -330,6 +330,7 @@ const VMStateDescription vmstate_riscv_cpu = {
> >           VMSTATE_UINTTL(env.siselect, RISCVCPU),
> >           VMSTATE_UINTTL(env.scounteren, RISCVCPU),
> >           VMSTATE_UINTTL(env.mcounteren, RISCVCPU),
> > +        VMSTATE_UINTTL(env.mcountinhibit, RISCVCPU),
> >           VMSTATE_UINTTL(env.sscratch, RISCVCPU),
> >           VMSTATE_UINTTL(env.mscratch, RISCVCPU),
> >           VMSTATE_UINT64(env.mfromhost, RISCVCPU),
>

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