mirror of
https://github.com/riscv-software-src/opensbi.git
synced 2026-05-23 14:21:32 +01:00
Dave Patel
718e1d194f
Add support for saving and restoring RISC-V floating-point (F/D) extension state in OpenSBI. This introduces a floating-point context structure and helper routines to perform full context save and restore. The floating-point context includes storage for all 32 FPi registers (f0–f31) along with the fcsr control and status register. The register state is saved and restored using double-precision load/store instructions (fsd/fld), and single-precision load/store instructions (fsw/flw) on an RV64 system with F and D-extension support. The implementation follows an eager context switching model where the entire FP state is saved and restored on every context switch. This avoids the need for trap-based lazy management and keeps the design simple and deterministic. Signed-off-by: Dave Patel <dave.patel@riscstar.com> Signed-off-by: Anup Patel <anup.patel@oss.qualcomm.com> Link: https://lore.kernel.org/r/20260518083023.997323-3-anup.patel@oss.qualcomm.com Signed-off-by: Anup Patel <anup@brainfault.org>
36 lines
680 B
C
36 lines
680 B
C
/*
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* SPDX-License-Identifier: BSD-2-Clause
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*
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* Copyright (c) 2026 RISCstar Solutions.
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*
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* Authors:
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* Dave Patel <dave.patel@riscstar.com>
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*/
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#ifndef __SBI_FP_H__
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#define __SBI_FP_H__
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#include <sbi/sbi_types.h>
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struct sbi_fp_context {
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#if __riscv_d
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uint64_t f[32];
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#else
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uint32_t f[32];
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#endif
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unsigned long fcsr;
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};
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#if defined(__riscv_f) || defined(__riscv_d)
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void sbi_fp_save(struct sbi_fp_context *dst);
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void sbi_fp_restore(const struct sbi_fp_context *src);
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#else
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static inline void sbi_fp_save(struct sbi_fp_context *dst)
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{
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}
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static inline void sbi_fp_restore(const struct sbi_fp_context *src)
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{
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}
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#endif /* __riscv_f || __riscv_d */
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#endif /*__SBI_FP_H__ */
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