mirror_ubuntu-kernels/arch/riscv/lib/uaccess_vector.S

54 lines
1.1 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-only */
#include <linux/linkage.h>
#include <asm-generic/export.h>
#include <asm/asm.h>
#include <asm/asm-extable.h>
#include <asm/csr.h>
#define pDst a0
#define pSrc a1
#define iNum a2
#define iVL a3
#define ELEM_LMUL_SETTING m8
#define vData v0
.macro fixup op reg addr lbl
100:
\op \reg, \addr
_asm_extable 100b, \lbl
.endm
SYM_FUNC_START(__asm_vector_usercopy)
/* Enable access to user memory */
li t6, SR_SUM
csrs CSR_STATUS, t6
loop:
vsetvli iVL, iNum, e8, ELEM_LMUL_SETTING, ta, ma
fixup vle8.v vData, (pSrc), 10f
sub iNum, iNum, iVL
add pSrc, pSrc, iVL
fixup vse8.v vData, (pDst), 11f
add pDst, pDst, iVL
bnez iNum, loop
/* Exception fixup for vector load is shared with normal exit */
10:
/* Disable access to user memory */
csrc CSR_STATUS, t6
mv a0, iNum
ret
/* Exception fixup code for vector store. */
11:
/* Undo the subtraction after vle8.v */
add iNum, iNum, iVL
/* Make sure the scalar fallback skip already processed bytes */
csrr t2, CSR_VSTART
sub iNum, iNum, t2
j 10b
SYM_FUNC_END(__asm_vector_usercopy)