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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 18:50:12 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 18:50:12 +0000 |
commit | 8665bd53f2f2e27e5511d90428cb3f60e6d0ce15 (patch) | |
tree | 8d58900dc0ebd4a3011f92c128d2fe45bc7c4bf2 /arch/riscv/include/asm/simd.h | |
parent | Adding debian version 6.7.12-1. (diff) | |
download | linux-8665bd53f2f2e27e5511d90428cb3f60e6d0ce15.tar.xz linux-8665bd53f2f2e27e5511d90428cb3f60e6d0ce15.zip |
Merging upstream version 6.8.9.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/riscv/include/asm/simd.h')
-rw-r--r-- | arch/riscv/include/asm/simd.h | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/riscv/include/asm/simd.h b/arch/riscv/include/asm/simd.h new file mode 100644 index 0000000000..54efbf523d --- /dev/null +++ b/arch/riscv/include/asm/simd.h @@ -0,0 +1,64 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2017 Linaro Ltd. <ard.biesheuvel@linaro.org> + * Copyright (C) 2023 SiFive + */ + +#ifndef __ASM_SIMD_H +#define __ASM_SIMD_H + +#include <linux/compiler.h> +#include <linux/irqflags.h> +#include <linux/percpu.h> +#include <linux/preempt.h> +#include <linux/types.h> +#include <linux/thread_info.h> + +#include <asm/vector.h> + +#ifdef CONFIG_RISCV_ISA_V +/* + * may_use_simd - whether it is allowable at this time to issue vector + * instructions or access the vector register file + * + * Callers must not assume that the result remains true beyond the next + * preempt_enable() or return from softirq context. + */ +static __must_check inline bool may_use_simd(void) +{ + /* + * RISCV_KERNEL_MODE_V is only set while preemption is disabled, + * and is clear whenever preemption is enabled. + */ + if (in_hardirq() || in_nmi()) + return false; + + /* + * Nesting is acheived in preempt_v by spreading the control for + * preemptible and non-preemptible kernel-mode Vector into two fields. + * Always try to match with prempt_v if kernel V-context exists. Then, + * fallback to check non preempt_v if nesting happens, or if the config + * is not set. + */ + if (IS_ENABLED(CONFIG_RISCV_ISA_V_PREEMPTIVE) && current->thread.kernel_vstate.datap) { + if (!riscv_preempt_v_started(current)) + return true; + } + /* + * Non-preemptible kernel-mode Vector temporarily disables bh. So we + * must not return true on irq_disabled(). Otherwise we would fail the + * lockdep check calling local_bh_enable() + */ + return !irqs_disabled() && !(riscv_v_flags() & RISCV_KERNEL_MODE_V); +} + +#else /* ! CONFIG_RISCV_ISA_V */ + +static __must_check inline bool may_use_simd(void) +{ + return false; +} + +#endif /* ! CONFIG_RISCV_ISA_V */ + +#endif |