diff mbox series

[v4,02/10] riscv: Add ISA extension parsing for pointer masking

Message ID 20240829010151.2813377-3-samuel.holland@sifive.com (mailing list archive)
State Superseded
Headers show
Series riscv: Userspace pointer masking and tagged address ABI | expand

Checks

Context Check Description
conchuod/vmtest-fixes-PR fail merge-conflict

Commit Message

Samuel Holland Aug. 29, 2024, 1:01 a.m. UTC
The RISC-V Pointer Masking specification defines three extensions:
Smmpm, Smnpm, and Ssnpm. Add support for parsing each of them. The
specific extension which provides pointer masking support to userspace
(Supm) depends on the kernel's privilege mode, so provide a macro to
abstract this selection.

Smmpm implies the existence of the mseccfg CSR. As it is the only user
of this CSR so far, there is no need for an Xlinuxmseccfg extension.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
---

(no changes since v3)

Changes in v3:
 - Rebase on riscv/for-next (ISA extension list conflicts)
 - Remove RISCV_ISA_EXT_SxPM, which was not used anywhere

Changes in v2:
 - Provide macros for the extension affecting the kernel and userspace

 arch/riscv/include/asm/hwcap.h | 5 +++++
 arch/riscv/kernel/cpufeature.c | 3 +++
 2 files changed, 8 insertions(+)

Comments

Charlie Jenkins Sept. 13, 2024, 1:09 a.m. UTC | #1
On Wed, Aug 28, 2024 at 06:01:24PM -0700, Samuel Holland wrote:
> The RISC-V Pointer Masking specification defines three extensions:
> Smmpm, Smnpm, and Ssnpm. Add support for parsing each of them. The
> specific extension which provides pointer masking support to userspace
> (Supm) depends on the kernel's privilege mode, so provide a macro to
> abstract this selection.
> 
> Smmpm implies the existence of the mseccfg CSR. As it is the only user
> of this CSR so far, there is no need for an Xlinuxmseccfg extension.
> 
> Signed-off-by: Samuel Holland <samuel.holland@sifive.com>

Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>

> ---
> 
> (no changes since v3)
> 
> Changes in v3:
>  - Rebase on riscv/for-next (ISA extension list conflicts)
>  - Remove RISCV_ISA_EXT_SxPM, which was not used anywhere
> 
> Changes in v2:
>  - Provide macros for the extension affecting the kernel and userspace
> 
>  arch/riscv/include/asm/hwcap.h | 5 +++++
>  arch/riscv/kernel/cpufeature.c | 3 +++
>  2 files changed, 8 insertions(+)
> 
> diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
> index 5a0bd27fd11a..aff21c6fc9b6 100644
> --- a/arch/riscv/include/asm/hwcap.h
> +++ b/arch/riscv/include/asm/hwcap.h
> @@ -92,6 +92,9 @@
>  #define RISCV_ISA_EXT_ZCF		83
>  #define RISCV_ISA_EXT_ZCMOP		84
>  #define RISCV_ISA_EXT_ZAWRS		85
> +#define RISCV_ISA_EXT_SMMPM		86
> +#define RISCV_ISA_EXT_SMNPM		87
> +#define RISCV_ISA_EXT_SSNPM		88
>  
>  #define RISCV_ISA_EXT_XLINUXENVCFG	127
>  
> @@ -100,8 +103,10 @@
>  
>  #ifdef CONFIG_RISCV_M_MODE
>  #define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SMAIA
> +#define RISCV_ISA_EXT_SUPM		RISCV_ISA_EXT_SMNPM
>  #else
>  #define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SSAIA
> +#define RISCV_ISA_EXT_SUPM		RISCV_ISA_EXT_SSNPM
>  #endif
>  
>  #endif /* _ASM_RISCV_HWCAP_H */
> diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> index b3b9735cb19a..ba3dc16e14dc 100644
> --- a/arch/riscv/kernel/cpufeature.c
> +++ b/arch/riscv/kernel/cpufeature.c
> @@ -377,9 +377,12 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
>  	__RISCV_ISA_EXT_BUNDLE(zvksg, riscv_zvksg_bundled_exts),
>  	__RISCV_ISA_EXT_DATA(zvkt, RISCV_ISA_EXT_ZVKT),
>  	__RISCV_ISA_EXT_DATA(smaia, RISCV_ISA_EXT_SMAIA),
> +	__RISCV_ISA_EXT_DATA(smmpm, RISCV_ISA_EXT_SMMPM),
> +	__RISCV_ISA_EXT_SUPERSET(smnpm, RISCV_ISA_EXT_SMNPM, riscv_xlinuxenvcfg_exts),
>  	__RISCV_ISA_EXT_DATA(smstateen, RISCV_ISA_EXT_SMSTATEEN),
>  	__RISCV_ISA_EXT_DATA(ssaia, RISCV_ISA_EXT_SSAIA),
>  	__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),
> +	__RISCV_ISA_EXT_SUPERSET(ssnpm, RISCV_ISA_EXT_SSNPM, riscv_xlinuxenvcfg_exts),
>  	__RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC),
>  	__RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL),
>  	__RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT),
> -- 
> 2.45.1
> 
> 
> _______________________________________________
> linux-riscv mailing list
> linux-riscv@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-riscv
diff mbox series

Patch

diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index 5a0bd27fd11a..aff21c6fc9b6 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -92,6 +92,9 @@ 
 #define RISCV_ISA_EXT_ZCF		83
 #define RISCV_ISA_EXT_ZCMOP		84
 #define RISCV_ISA_EXT_ZAWRS		85
+#define RISCV_ISA_EXT_SMMPM		86
+#define RISCV_ISA_EXT_SMNPM		87
+#define RISCV_ISA_EXT_SSNPM		88
 
 #define RISCV_ISA_EXT_XLINUXENVCFG	127
 
@@ -100,8 +103,10 @@ 
 
 #ifdef CONFIG_RISCV_M_MODE
 #define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SMAIA
+#define RISCV_ISA_EXT_SUPM		RISCV_ISA_EXT_SMNPM
 #else
 #define RISCV_ISA_EXT_SxAIA		RISCV_ISA_EXT_SSAIA
+#define RISCV_ISA_EXT_SUPM		RISCV_ISA_EXT_SSNPM
 #endif
 
 #endif /* _ASM_RISCV_HWCAP_H */
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index b3b9735cb19a..ba3dc16e14dc 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -377,9 +377,12 @@  const struct riscv_isa_ext_data riscv_isa_ext[] = {
 	__RISCV_ISA_EXT_BUNDLE(zvksg, riscv_zvksg_bundled_exts),
 	__RISCV_ISA_EXT_DATA(zvkt, RISCV_ISA_EXT_ZVKT),
 	__RISCV_ISA_EXT_DATA(smaia, RISCV_ISA_EXT_SMAIA),
+	__RISCV_ISA_EXT_DATA(smmpm, RISCV_ISA_EXT_SMMPM),
+	__RISCV_ISA_EXT_SUPERSET(smnpm, RISCV_ISA_EXT_SMNPM, riscv_xlinuxenvcfg_exts),
 	__RISCV_ISA_EXT_DATA(smstateen, RISCV_ISA_EXT_SMSTATEEN),
 	__RISCV_ISA_EXT_DATA(ssaia, RISCV_ISA_EXT_SSAIA),
 	__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),
+	__RISCV_ISA_EXT_SUPERSET(ssnpm, RISCV_ISA_EXT_SSNPM, riscv_xlinuxenvcfg_exts),
 	__RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC),
 	__RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL),
 	__RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT),