[PATCH v1] RISC-V: Add basic support for the vector extension

[PATCH v1] RISC-V: Add basic support for the vector extension

[Conor Dooley]

From: Conor Dooley <conor.dooley@microchip.com>

I've started hitting this in CI while testing Andy's vector enablement
series. I'm not entirely sure if there is more to do here, other than
squeezing in the duplicate of what has been done for other extensions.

Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
This is based on top of patches already on the sparse list, adding
support for some multi-letter extensions for RISC-V:
https://lore.kernel.org/linux-sparse/20220811033138.20676-1-palmer@rivosinc.com/
https://lore.kernel.org/linux-sparse/20220811052957.16634-1-palmer@rivosinc.com/

CC: luc.vanoostenryck@gmail.com
CC: palmer@dabbelt.com
CC: linux-sparse@vger.kernel.org
CC: linux-riscv@lists.infradead.org
---
 target-riscv.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/target-riscv.c b/target-riscv.c
index 8338d7a6..c8282814 100644
--- a/target-riscv.c
+++ b/target-riscv.c
@@ -21,6 +21,7 @@
 #define RISCV_ZIFENCEI		(1 << 11)
 #define RISCV_ZICBOM		(1 << 12)
 #define RISCV_ZIHINTPAUSE	(1 << 13)
+#define RISCV_VECTOR		(1 << 14)
 
 static unsigned int riscv_flags;
 
@@ -41,6 +42,7 @@ static void parse_march_riscv(const char *arg)
 		{ "f",			RISCV_FLOAT|RISCV_FDIV|RISCV_ZICSR },
 		{ "d",			RISCV_DOUBLE|RISCV_FDIV|RISCV_ZICSR },
 		{ "c",			RISCV_COMP },
+		{ "v",			RISCV_VECTOR },
 		{ "_zicsr",		RISCV_ZICSR },
 		{ "_zifencei",		RISCV_ZIFENCEI },
 		{ "_zicbom",		RISCV_ZICBOM },
@@ -147,6 +149,8 @@ static void predefine_riscv(const struct target *self)
 		predefine("__riscv_zicbom", 1, "1");
 	if (riscv_flags & RISCV_ZIHINTPAUSE)
 		predefine("__riscv_zihintpause", 1, "1");
+	if (riscv_flags & RISCV_VECTOR)
+		predefine("__riscv_vector", 1, "1");
 
 	if (cmodel)
 		predefine_strong("__riscv_cmodel_%s", cmodel);
-- 
2.39.2

Re: [PATCH v1] RISC-V: Add basic support for the vector extension

[Palmer Dabbelt]

On Mon, 06 Mar 2023 14:23:22 PST (-0800), Conor Dooley wrote:
> From: Conor Dooley <conor.dooley@microchip.com>
>
> I've started hitting this in CI while testing Andy's vector enablement
> series. I'm not entirely sure if there is more to do here, other than
> squeezing in the duplicate of what has been done for other extensions.
>
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---
> This is based on top of patches already on the sparse list, adding
> support for some multi-letter extensions for RISC-V:
> https://lore.kernel.org/linux-sparse/20220811033138.20676-1-palmer@rivosinc.com/
> https://lore.kernel.org/linux-sparse/20220811052957.16634-1-palmer@rivosinc.com/
>
> CC: luc.vanoostenryck@gmail.com
> CC: palmer@dabbelt.com
> CC: linux-sparse@vger.kernel.org
> CC: linux-riscv@lists.infradead.org
> ---
>  target-riscv.c | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/target-riscv.c b/target-riscv.c
> index 8338d7a6..c8282814 100644
> --- a/target-riscv.c
> +++ b/target-riscv.c
> @@ -21,6 +21,7 @@
>  #define RISCV_ZIFENCEI		(1 << 11)
>  #define RISCV_ZICBOM		(1 << 12)
>  #define RISCV_ZIHINTPAUSE	(1 << 13)
> +#define RISCV_VECTOR		(1 << 14)
>
>  static unsigned int riscv_flags;
>
> @@ -41,6 +42,7 @@ static void parse_march_riscv(const char *arg)
>  		{ "f",			RISCV_FLOAT|RISCV_FDIV|RISCV_ZICSR },
>  		{ "d",			RISCV_DOUBLE|RISCV_FDIV|RISCV_ZICSR },
>  		{ "c",			RISCV_COMP },
> +		{ "v",			RISCV_VECTOR },
>  		{ "_zicsr",		RISCV_ZICSR },
>  		{ "_zifencei",		RISCV_ZIFENCEI },
>  		{ "_zicbom",		RISCV_ZICBOM },
> @@ -147,6 +149,8 @@ static void predefine_riscv(const struct target *self)
>  		predefine("__riscv_zicbom", 1, "1");
>  	if (riscv_flags & RISCV_ZIHINTPAUSE)
>  		predefine("__riscv_zihintpause", 1, "1");
> +	if (riscv_flags & RISCV_VECTOR)
> +		predefine("__riscv_vector", 1, "1");

V adds a bunch of V-subset extensions.  I don't think we need to 
faithfully handle those, but we should at least set the right element 
type and length fields for V as code might depend on those.

>
>  	if (cmodel)
>  		predefine_strong("__riscv_cmodel_%s", cmodel);