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: Charlie Jenkins charlie@rivosinc.com --- arch/riscv/include/asm/hwprobe.h | 4 +-- .../include/asm/vendor_extensions/thead_hwprobe.h | 11 ++++++ arch/riscv/include/uapi/asm/hwprobe.h | 3 +- arch/riscv/include/uapi/asm/vendor/thead.h | 3 ++ arch/riscv/kernel/sys_hwprobe.c | 9 +++++ arch/riscv/kernel/vendor_extensions/Makefile | 1 + .../riscv/kernel/vendor_extensions/thead_hwprobe.c | 42 ++++++++++++++++++++++ 7 files changed, 70 insertions(+), 3 deletions(-)
diff --git a/arch/riscv/include/asm/hwprobe.h b/arch/riscv/include/asm/hwprobe.h index 630507dff5ea..e68496b4f8de 100644 --- a/arch/riscv/include/asm/hwprobe.h +++ b/arch/riscv/include/asm/hwprobe.h @@ -1,6 +1,6 @@ /* 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 6 +#define RISCV_HWPROBE_MAX_KEY 7
static inline bool riscv_hwprobe_key_is_valid(__s64 key) { diff --git a/arch/riscv/include/asm/vendor_extensions/thead_hwprobe.h b/arch/riscv/include/asm/vendor_extensions/thead_hwprobe.h new file mode 100644 index 000000000000..907cfc4eb4dc --- /dev/null +++ b/arch/riscv/include/asm/vendor_extensions/thead_hwprobe.h @@ -0,0 +1,11 @@ +/* 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> + +void hwprobe_isa_vendor_ext_thead_0(struct riscv_hwprobe *pair, const struct cpumask *cpus); + +#endif diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h index 9f2a8e3ff204..21e96a63f9ea 100644 --- a/arch/riscv/include/uapi/asm/hwprobe.h +++ b/arch/riscv/include/uapi/asm/hwprobe.h @@ -1,6 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ /* - * Copyright 2023 Rivos, Inc + * Copyright 2023-2024 Rivos, Inc */
#ifndef _UAPI_ASM_HWPROBE_H @@ -67,6 +67,7 @@ struct riscv_hwprobe { #define RISCV_HWPROBE_MISALIGNED_UNSUPPORTED (4 << 0) #define RISCV_HWPROBE_MISALIGNED_MASK (7 << 0) #define RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE 6 +#define RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0 7 /* Increase RISCV_HWPROBE_MAX_KEY when adding items. */
/* Flags */ diff --git a/arch/riscv/include/uapi/asm/vendor/thead.h b/arch/riscv/include/uapi/asm/vendor/thead.h new file mode 100644 index 000000000000..43790ebe5faf --- /dev/null +++ b/arch/riscv/include/uapi/asm/vendor/thead.h @@ -0,0 +1,3 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ + +#define RISCV_HWPROBE_VENDOR_EXT_XTHEADVECTOR (1 << 0) diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c index 8cae41a502dd..e59cac545df5 100644 --- a/arch/riscv/kernel/sys_hwprobe.c +++ b/arch/riscv/kernel/sys_hwprobe.c @@ -13,6 +13,7 @@ #include <asm/uaccess.h> #include <asm/unistd.h> #include <asm/vector.h> +#include <asm/vendor_extensions/thead_hwprobe.h> #include <vdso/vsyscall.h>
@@ -216,6 +217,14 @@ static void hwprobe_one_pair(struct riscv_hwprobe *pair, pair->value = riscv_cboz_block_size; break;
+ case RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0: +#ifdef CONFIG_RISCV_ISA_VENDOR_EXT_THEAD + hwprobe_isa_vendor_ext_thead_0(pair, cpus); +#else + pair->value = 0; +#endif + break; + /* * For forward compatibility, unknown keys don't fail the whole * call, but get their element key set to -1 and value set to 0 diff --git a/arch/riscv/kernel/vendor_extensions/Makefile b/arch/riscv/kernel/vendor_extensions/Makefile index 8f1c5a4dc38f..f511fd269e8a 100644 --- a/arch/riscv/kernel/vendor_extensions/Makefile +++ b/arch/riscv/kernel/vendor_extensions/Makefile @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0-only
obj-$(CONFIG_RISCV_ISA_VENDOR_EXT_THEAD) += thead.o +obj-$(CONFIG_RISCV_ISA_VENDOR_EXT_THEAD) += thead_hwprobe.o obj-$(CONFIG_RISCV_ISA_VENDOR_EXT_ANDES) += andes.o diff --git a/arch/riscv/kernel/vendor_extensions/thead_hwprobe.c b/arch/riscv/kernel/vendor_extensions/thead_hwprobe.c new file mode 100644 index 000000000000..e8e2de292032 --- /dev/null +++ b/arch/riscv/kernel/vendor_extensions/thead_hwprobe.c @@ -0,0 +1,42 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <asm/vector.h> +#include <asm/vendor_extensions/thead.h> +#include <asm/vendor_extensions/thead_hwprobe.h> + +#include <linux/cpumask.h> +#include <linux/types.h> + +#include <uapi/asm/hwprobe.h> +#include <uapi/asm/vendor/thead.h> + +void hwprobe_isa_vendor_ext_thead_0(struct riscv_hwprobe *pair, const struct cpumask *cpus) +{ + /* + * Loop through and record extensions that 1) anyone has, and 2) anyone + * doesn't have. + */ + + struct riscv_isainfo *per_hart_thead_bitmap = riscv_isa_vendor_ext_list_thead.per_hart_vendor_bitmap; + int cpu; + u64 missing; + + for_each_cpu(cpu, cpus) { + struct riscv_isainfo *isainfo = &per_hart_thead_bitmap[cpu]; + +#define 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) + + EXT_KEY(XTHEADVECTOR); + +#undef EXT_KEY + } + + /* Now turn off reporting features if any CPU is missing it. */ + pair->value &= ~missing; +}