Unverified Commit a5ea53da authored by Charlie Jenkins's avatar Charlie Jenkins Committed by Palmer Dabbelt
Browse files

riscv: hwprobe: Add thead vendor extension probing 



Add a new hwprobe key "RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0" which
allows userspace to probe for the new RISCV_ISA_VENDOR_EXT_XTHEADVECTOR
vendor extension.

This new key will allow userspace code to probe for which thead vendor
extensions are supported. This API is modeled to be consistent with
RISCV_HWPROBE_KEY_IMA_EXT_0. The bitmask returned will have each bit
corresponding to a supported thead vendor extension of the cpumask set.
Just like RISCV_HWPROBE_KEY_IMA_EXT_0, this allows a userspace program
to determine all of the supported thead vendor extensions in one call.

Signed-off-by: default avatarCharlie Jenkins <charlie@rivosinc.com>
Reviewed-by: default avatarEvan Green <evan@rivosinc.com>
Tested-by: default avatarYangyu Chen <cyy@cyyself.name>
Link: https://lore.kernel.org/r/20241113-xtheadvector-v11-10-236c22791ef9@rivosinc.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent d863910e

arch/riscv/include/asm/hwprobe.h

+3 −2
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */

/*

 * Copyright 2023 Rivos, Inc

 * Copyright 2023-2024 Rivos, Inc

 */



#ifndef _ASM_HWPROBE_H
@@ -8,7 +8,7 @@ 


#include <uapi/asm/hwprobe.h>



#define RISCV_HWPROBE_MAX_KEY 10

#define RISCV_HWPROBE_MAX_KEY 11



static inline bool riscv_hwprobe_key_is_valid(__s64 key)

{
@@ -21,6 +21,7 @@ static inline bool hwprobe_key_is_bitmask(__s64 key) 
	case RISCV_HWPROBE_KEY_BASE_BEHAVIOR:

	case RISCV_HWPROBE_KEY_IMA_EXT_0:

	case RISCV_HWPROBE_KEY_CPUPERF_0:

	case RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0:

		return true;

	}

arch/riscv/include/asm/vendor_extensions/thead_hwprobe.h

0 → 100644
+19 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef _ASM_RISCV_VENDOR_EXTENSIONS_THEAD_HWPROBE_H

#define _ASM_RISCV_VENDOR_EXTENSIONS_THEAD_HWPROBE_H



#include <linux/cpumask.h>



#include <uapi/asm/hwprobe.h>



#ifdef CONFIG_RISCV_ISA_VENDOR_EXT_THEAD

void hwprobe_isa_vendor_ext_thead_0(struct riscv_hwprobe *pair, const struct cpumask *cpus);

#else

static inline void hwprobe_isa_vendor_ext_thead_0(struct riscv_hwprobe *pair,

						  const struct cpumask *cpus)

{

	pair->value = 0;

}

#endif



#endif

arch/riscv/include/asm/vendor_extensions/vendor_hwprobe.h

0 → 100644
+37 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

/*

 * Copyright 2024 Rivos, Inc

 */



#ifndef _ASM_RISCV_SYS_HWPROBE_H

#define _ASM_RISCV_SYS_HWPROBE_H



#include <asm/cpufeature.h>



#define VENDOR_EXT_KEY(ext)								\

	do {										\

		if (__riscv_isa_extension_available(isainfo->isa, RISCV_ISA_VENDOR_EXT_##ext)) \

			pair->value |= RISCV_HWPROBE_VENDOR_EXT_##ext;			\

		else									\

			missing |= RISCV_HWPROBE_VENDOR_EXT_##ext;			\

	} while (false)



/*

 * Loop through and record extensions that 1) anyone has, and 2) anyone

 * doesn't have.

 *

 * _extension_checks is an arbitrary C block to set the values of pair->value

 * and missing. It should be filled with VENDOR_EXT_KEY expressions.

 */

#define VENDOR_EXTENSION_SUPPORTED(pair, cpus, per_hart_vendor_bitmap, _extension_checks)	\

	do {											\

		int cpu;									\

		u64 missing = 0;								\

		for_each_cpu(cpu, (cpus)) {							\

			struct riscv_isavendorinfo *isainfo = &(per_hart_vendor_bitmap)[cpu];	\

			_extension_checks							\

		}										\

		(pair)->value &= ~missing;							\

	} while (false)										\



#endif /* _ASM_RISCV_SYS_HWPROBE_H */

arch/riscv/include/uapi/asm/hwprobe.h

+2 −1
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */

/*

 * Copyright 2023 Rivos, Inc

 * Copyright 2023-2024 Rivos, Inc

 */



#ifndef _UAPI_ASM_HWPROBE_H
@@ -94,6 +94,7 @@ struct riscv_hwprobe { 
#define		RISCV_HWPROBE_MISALIGNED_VECTOR_SLOW		2

#define		RISCV_HWPROBE_MISALIGNED_VECTOR_FAST		3

#define		RISCV_HWPROBE_MISALIGNED_VECTOR_UNSUPPORTED	4

#define RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0	11

/* Increase RISCV_HWPROBE_MAX_KEY when adding items. */



/* Flags */

arch/riscv/include/uapi/asm/vendor/thead.h

0 → 100644
+3 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */



#define		RISCV_HWPROBE_VENDOR_EXT_XTHEADVECTOR	(1 << 0)