diff mbox series

[v3] target: riscv: Add Svvptc extension support

Message ID 20240828083651.203861-1-alexghiti@rivosinc.com (mailing list archive)
State New, archived
Headers show
Series [v3] target: riscv: Add Svvptc extension support | expand

Commit Message

Alexandre Ghiti Aug. 28, 2024, 8:36 a.m. UTC 
The Svvptc extension describes a uarch that does not cache invalid TLB
entries: that's the case for qemu so there is nothing particular to
implement other than the introduction of this extension.

Since qemu already exposes Svvptc behaviour, let's enable it by default
since it allows to drastically reduce the number of sfence.vma emitted
by S-mode.

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
---

Changes in v3:
- Rebase on top of master
- Change 1.12 to 1.13 spec version (drew)

Changes in v2:
- Rebase on top of master
- Enable Svvptc by default

 target/riscv/cpu.c     | 2 ++
 target/riscv/cpu_cfg.h | 1 +
 2 files changed, 3 insertions(+)

Comments

Alistair Francis Sept. 9, 2024, 3:33 a.m. UTC | #1 
On Wed, Aug 28, 2024 at 6:37 PM Alexandre Ghiti <alexghiti@rivosinc.com> wrote:
>
> The Svvptc extension describes a uarch that does not cache invalid TLB
> entries: that's the case for qemu so there is nothing particular to
> implement other than the introduction of this extension.
>
> Since qemu already exposes Svvptc behaviour, let's enable it by default
> since it allows to drastically reduce the number of sfence.vma emitted
> by S-mode.
>
> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>

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

Alistair

> ---
>
> Changes in v3:
> - Rebase on top of master
> - Change 1.12 to 1.13 spec version (drew)
>
> Changes in v2:
> - Rebase on top of master
> - Enable Svvptc by default
>
>  target/riscv/cpu.c     | 2 ++
>  target/riscv/cpu_cfg.h | 1 +
>  2 files changed, 3 insertions(+)
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index a90808a3ba..cabe698f2f 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -197,6 +197,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
>      ISA_EXT_DATA_ENTRY(svinval, PRIV_VERSION_1_12_0, ext_svinval),
>      ISA_EXT_DATA_ENTRY(svnapot, PRIV_VERSION_1_12_0, ext_svnapot),
>      ISA_EXT_DATA_ENTRY(svpbmt, PRIV_VERSION_1_12_0, ext_svpbmt),
> +    ISA_EXT_DATA_ENTRY(svvptc, PRIV_VERSION_1_13_0, ext_svvptc),
>      ISA_EXT_DATA_ENTRY(xtheadba, PRIV_VERSION_1_11_0, ext_xtheadba),
>      ISA_EXT_DATA_ENTRY(xtheadbb, PRIV_VERSION_1_11_0, ext_xtheadbb),
>      ISA_EXT_DATA_ENTRY(xtheadbs, PRIV_VERSION_1_11_0, ext_xtheadbs),
> @@ -1509,6 +1510,7 @@ const RISCVCPUMultiExtConfig riscv_cpu_extensions[] = {
>      MULTI_EXT_CFG_BOOL("svinval", ext_svinval, false),
>      MULTI_EXT_CFG_BOOL("svnapot", ext_svnapot, false),
>      MULTI_EXT_CFG_BOOL("svpbmt", ext_svpbmt, false),
> +    MULTI_EXT_CFG_BOOL("svvptc", ext_svvptc, true),
>
>      MULTI_EXT_CFG_BOOL("zicntr", ext_zicntr, true),
>      MULTI_EXT_CFG_BOOL("zihpm", ext_zihpm, true),
> diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
> index 8b272fb826..7d16048a76 100644
> --- a/target/riscv/cpu_cfg.h
> +++ b/target/riscv/cpu_cfg.h
> @@ -81,6 +81,7 @@ struct RISCVCPUConfig {
>      bool ext_svinval;
>      bool ext_svnapot;
>      bool ext_svpbmt;
> +    bool ext_svvptc;
>      bool ext_zdinx;
>      bool ext_zaamo;
>      bool ext_zacas;
> --
> 2.39.2
>
>
Alistair Francis Sept. 9, 2024, 3:37 a.m. UTC | #2 
On Wed, Aug 28, 2024 at 6:37 PM Alexandre Ghiti <alexghiti@rivosinc.com> wrote:
>
> The Svvptc extension describes a uarch that does not cache invalid TLB
> entries: that's the case for qemu so there is nothing particular to
> implement other than the introduction of this extension.
>
> Since qemu already exposes Svvptc behaviour, let's enable it by default
> since it allows to drastically reduce the number of sfence.vma emitted
> by S-mode.
>
> Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>

Thanks!

Applied to riscv-to-apply.next

Alistair

> ---
>
> Changes in v3:
> - Rebase on top of master
> - Change 1.12 to 1.13 spec version (drew)
>
> Changes in v2:
> - Rebase on top of master
> - Enable Svvptc by default
>
>  target/riscv/cpu.c     | 2 ++
>  target/riscv/cpu_cfg.h | 1 +
>  2 files changed, 3 insertions(+)
>
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index a90808a3ba..cabe698f2f 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -197,6 +197,7 @@ const RISCVIsaExtData isa_edata_arr[] = {
>      ISA_EXT_DATA_ENTRY(svinval, PRIV_VERSION_1_12_0, ext_svinval),
>      ISA_EXT_DATA_ENTRY(svnapot, PRIV_VERSION_1_12_0, ext_svnapot),
>      ISA_EXT_DATA_ENTRY(svpbmt, PRIV_VERSION_1_12_0, ext_svpbmt),
> +    ISA_EXT_DATA_ENTRY(svvptc, PRIV_VERSION_1_13_0, ext_svvptc),
>      ISA_EXT_DATA_ENTRY(xtheadba, PRIV_VERSION_1_11_0, ext_xtheadba),
>      ISA_EXT_DATA_ENTRY(xtheadbb, PRIV_VERSION_1_11_0, ext_xtheadbb),
>      ISA_EXT_DATA_ENTRY(xtheadbs, PRIV_VERSION_1_11_0, ext_xtheadbs),
> @@ -1509,6 +1510,7 @@ const RISCVCPUMultiExtConfig riscv_cpu_extensions[] = {
>      MULTI_EXT_CFG_BOOL("svinval", ext_svinval, false),
>      MULTI_EXT_CFG_BOOL("svnapot", ext_svnapot, false),
>      MULTI_EXT_CFG_BOOL("svpbmt", ext_svpbmt, false),
> +    MULTI_EXT_CFG_BOOL("svvptc", ext_svvptc, true),
>
>      MULTI_EXT_CFG_BOOL("zicntr", ext_zicntr, true),
>      MULTI_EXT_CFG_BOOL("zihpm", ext_zihpm, true),
> diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
> index 8b272fb826..7d16048a76 100644
> --- a/target/riscv/cpu_cfg.h
> +++ b/target/riscv/cpu_cfg.h
> @@ -81,6 +81,7 @@ struct RISCVCPUConfig {
>      bool ext_svinval;
>      bool ext_svnapot;
>      bool ext_svpbmt;
> +    bool ext_svvptc;
>      bool ext_zdinx;
>      bool ext_zaamo;
>      bool ext_zacas;
> --
> 2.39.2
>
>
diff mbox series

Patch

diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
index a90808a3ba..cabe698f2f 100644
--- a/target/riscv/cpu.c
+++ b/target/riscv/cpu.c
@@ -197,6 +197,7 @@  const RISCVIsaExtData isa_edata_arr[] = {
     ISA_EXT_DATA_ENTRY(svinval, PRIV_VERSION_1_12_0, ext_svinval),
     ISA_EXT_DATA_ENTRY(svnapot, PRIV_VERSION_1_12_0, ext_svnapot),
     ISA_EXT_DATA_ENTRY(svpbmt, PRIV_VERSION_1_12_0, ext_svpbmt),
+    ISA_EXT_DATA_ENTRY(svvptc, PRIV_VERSION_1_13_0, ext_svvptc),
     ISA_EXT_DATA_ENTRY(xtheadba, PRIV_VERSION_1_11_0, ext_xtheadba),
     ISA_EXT_DATA_ENTRY(xtheadbb, PRIV_VERSION_1_11_0, ext_xtheadbb),
     ISA_EXT_DATA_ENTRY(xtheadbs, PRIV_VERSION_1_11_0, ext_xtheadbs),
@@ -1509,6 +1510,7 @@  const RISCVCPUMultiExtConfig riscv_cpu_extensions[] = {
     MULTI_EXT_CFG_BOOL("svinval", ext_svinval, false),
     MULTI_EXT_CFG_BOOL("svnapot", ext_svnapot, false),
     MULTI_EXT_CFG_BOOL("svpbmt", ext_svpbmt, false),
+    MULTI_EXT_CFG_BOOL("svvptc", ext_svvptc, true),
 
     MULTI_EXT_CFG_BOOL("zicntr", ext_zicntr, true),
     MULTI_EXT_CFG_BOOL("zihpm", ext_zihpm, true),
diff --git a/target/riscv/cpu_cfg.h b/target/riscv/cpu_cfg.h
index 8b272fb826..7d16048a76 100644
--- a/target/riscv/cpu_cfg.h
+++ b/target/riscv/cpu_cfg.h
@@ -81,6 +81,7 @@  struct RISCVCPUConfig {
     bool ext_svinval;
     bool ext_svnapot;
     bool ext_svpbmt;
+    bool ext_svvptc;
     bool ext_zdinx;
     bool ext_zaamo;
     bool ext_zacas;