include: Add hard FP access macros and defines

This patch adds hardware floating-point (hard FP) access
macros and defines.

Signed-off-by: Anup Patel <anup.patel@wdc.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/include/sbi/riscv_fp.h b/include/sbi/riscv_fp.h
new file mode 100644
index 0000000..0deb8e4
--- /dev/null
+++ b/include/sbi/riscv_fp.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (c) 2019 Western Digital Corporation or its affiliates.
+ *
+ * Authors:
+ *   Anup Patel <anup.patel@wdc.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#ifndef __RISCV_FP_H__
+#define __RISCV_FP_H__
+
+#include <sbi/riscv_asm.h>
+#include <sbi/riscv_encoding.h>
+#include <sbi/sbi_types.h>
+
+#define GET_PRECISION(insn) (((insn) >> 25) & 3)
+#define GET_RM(insn) (((insn) >> 12) & 7)
+#define PRECISION_S 0
+#define PRECISION_D 1
+
+#ifdef __riscv_flen
+
+#define GET_F32_REG(insn, pos, regs) ({ \
+  register s32 value asm("a0") = SHIFT_RIGHT(insn, (pos)-3) & 0xf8; \
+  ulong tmp; \
+  asm ("1: auipc %0, %%pcrel_hi(get_f32_reg); add %0, %0, %1; jalr t0, %0, %%pcrel_lo(1b)" : "=&r"(tmp), "+&r"(value) :: "t0"); \
+  value; })
+#define SET_F32_REG(insn, pos, regs, val) ({ \
+  register u32 value asm("a0") = (val); \
+  ulong offset = SHIFT_RIGHT(insn, (pos)-3) & 0xf8; \
+  ulong tmp; \
+  asm volatile ("1: auipc %0, %%pcrel_hi(put_f32_reg); add %0, %0, %2; jalr t0, %0, %%pcrel_lo(1b)" : "=&r"(tmp) : "r"(value), "r"(offset) : "t0"); })
+#define init_fp_reg(i) SET_F32_REG((i) << 3, 3, 0, 0)
+#define GET_F64_REG(insn, pos, regs) ({ \
+  register ulong value asm("a0") = SHIFT_RIGHT(insn, (pos)-3) & 0xf8; \
+  ulong tmp; \
+  asm ("1: auipc %0, %%pcrel_hi(get_f64_reg); add %0, %0, %1; jalr t0, %0, %%pcrel_lo(1b)" : "=&r"(tmp), "+&r"(value) :: "t0"); \
+  sizeof(ulong) == 4 ? *(int64_t*)value : (int64_t)value; })
+#define SET_F64_REG(insn, pos, regs, val) ({ \
+  uint64_t __val = (val); \
+  register ulong value asm("a0") = sizeof(ulong) == 4 ? (ulong)&__val : (ulong)__val; \
+  ulong offset = SHIFT_RIGHT(insn, (pos)-3) & 0xf8; \
+  ulong tmp; \
+  asm volatile ("1: auipc %0, %%pcrel_hi(put_f64_reg); add %0, %0, %2; jalr t0, %0, %%pcrel_lo(1b)" : "=&r"(tmp) : "r"(value), "r"(offset) : "t0"); })
+#define GET_FCSR() csr_read(fcsr)
+#define SET_FCSR(value) csr_write(fcsr, (value))
+#define GET_FRM() csr_read(frm)
+#define SET_FRM(value) csr_write(frm, (value))
+#define GET_FFLAGS() csr_read(fflags)
+#define SET_FFLAGS(value) csr_write(fflags, (value))
+
+#define SET_FS_DIRTY() ((void) 0)
+
+#else
+#error "Floating point emulation not supported.\n"
+#endif
+
+#define GET_F32_RS1(insn, regs) (GET_F32_REG(insn, 15, regs))
+#define GET_F32_RS2(insn, regs) (GET_F32_REG(insn, 20, regs))
+#define GET_F32_RS3(insn, regs) (GET_F32_REG(insn, 27, regs))
+#define GET_F64_RS1(insn, regs) (GET_F64_REG(insn, 15, regs))
+#define GET_F64_RS2(insn, regs) (GET_F64_REG(insn, 20, regs))
+#define GET_F64_RS3(insn, regs) (GET_F64_REG(insn, 27, regs))
+#define SET_F32_RD(insn, regs, val) (SET_F32_REG(insn, 7, regs, val), SET_FS_DIRTY())
+#define SET_F64_RD(insn, regs, val) (SET_F64_REG(insn, 7, regs, val), SET_FS_DIRTY())
+
+#define GET_F32_RS2C(insn, regs) (GET_F32_REG(insn, 2, regs))
+#define GET_F32_RS2S(insn, regs) (GET_F32_REG(RVC_RS2S(insn), 0, regs))
+#define GET_F64_RS2C(insn, regs) (GET_F64_REG(insn, 2, regs))
+#define GET_F64_RS2S(insn, regs) (GET_F64_REG(RVC_RS2S(insn), 0, regs))
+
+#endif