On Sun, Jun 9, 2024 at 9:45 PM Charlie Jenkins charlie@rivosinc.com wrote:
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 Reviewed-by: Evan Green evan@rivosinc.com
You can continue to keep my tag, but I came up with some nits to pick anyway.
arch/riscv/include/asm/hwprobe.h | 4 +-- .../include/asm/vendor_extensions/thead_hwprobe.h | 18 +++++++++++ .../include/asm/vendor_extensions/vendor_hwprobe.h | 37 ++++++++++++++++++++++ arch/riscv/include/uapi/asm/hwprobe.h | 3 +- arch/riscv/include/uapi/asm/vendor/thead.h | 3 ++ arch/riscv/kernel/sys_hwprobe.c | 5 +++ arch/riscv/kernel/vendor_extensions/Makefile | 1 + .../riscv/kernel/vendor_extensions/thead_hwprobe.c | 19 +++++++++++ 8 files changed, 87 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..925fef39a2c0 --- /dev/null +++ b/arch/riscv/include/asm/vendor_extensions/thead_hwprobe.h @@ -0,0 +1,18 @@ +/* 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 diff --git a/arch/riscv/include/asm/vendor_extensions/vendor_hwprobe.h b/arch/riscv/include/asm/vendor_extensions/vendor_hwprobe.h new file mode 100644 index 000000000000..b6222e7b519e --- /dev/null +++ b/arch/riscv/include/asm/vendor_extensions/vendor_hwprobe.h @@ -0,0 +1,37 @@ +/* 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 EXT_KEY(ext) \
Nit: Do you think it should be VENDOR_EXT_KEY? I had a slight ping of worry that the identifier sounds so generic it might conflict with something later, but meh maybe it's fine.
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 EXT_KEY expressions.
- */
+#define VENDOR_EXTENSION_SUPPORTED(pair, cpus, per_hart_thead_bitmap, _extension_checks) \
Nit: This macro was meant to be generic for all vendors, but you've named one of the parameters per_hart_thead_bitmap. :)
do { \int cpu; \u64 missing; \for_each_cpu(cpu, (cpus)) { \struct riscv_isavendorinfo *isainfo = &(per_hart_thead_bitmap)[cpu]; \_extension_checks \} \(pair)->value &= ~missing; \} while (false) \+#endif /* _ASM_RISCV_SYS_HWPROBE_H */ diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h index dda76a05420b..155a83dd1cdf 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 @@ -68,6 +68,7 @@ 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 969ef3d59dbe..e39fa70083d3 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>
@@ -217,6 +218,10 @@ static void hwprobe_one_pair(struct riscv_hwprobe *pair, pair->value = riscv_cboz_block_size; break;
case RISCV_HWPROBE_KEY_VENDOR_EXT_THEAD_0:hwprobe_isa_vendor_ext_thead_0(pair, cpus);break;/* * For forward compatibility, unknown keys don't fail the whole * call, but get their element key set to -1 and value set to 0diff --git a/arch/riscv/kernel/vendor_extensions/Makefile b/arch/riscv/kernel/vendor_extensions/Makefile index 353522cb3bf0..866414c81a9f 100644 --- a/arch/riscv/kernel/vendor_extensions/Makefile +++ b/arch/riscv/kernel/vendor_extensions/Makefile @@ -2,3 +2,4 @@
obj-$(CONFIG_RISCV_ISA_VENDOR_EXT_ANDES) += andes.o obj-$(CONFIG_RISCV_ISA_VENDOR_EXT_THEAD) += thead.o +obj-$(CONFIG_RISCV_ISA_VENDOR_EXT_THEAD) += thead_hwprobe.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..53f65942f7e8 --- /dev/null +++ b/arch/riscv/kernel/vendor_extensions/thead_hwprobe.c @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0-only
+#include <asm/vendor_extensions/thead.h> +#include <asm/vendor_extensions/thead_hwprobe.h> +#include <asm/vendor_extensions/vendor_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) +{
VENDOR_EXTENSION_SUPPORTED(pair, cpus,riscv_isa_vendor_ext_list_thead.per_hart_isa_bitmap, {EXT_KEY(XTHEADVECTOR);});+}
-- 2.44.0