[PATCH v2 09/17] riscv: uaccess: Add alternative for xtheadvector uaccess

Charlie Jenkins charlie at rivosinc.com
Mon Apr 15 21:12:06 PDT 2024


At this time, use the fallback uaccess routines rather than customizing
the vectorized uaccess routines to be compatible with xtheadvector.

Signed-off-by: Charlie Jenkins <charlie at rivosinc.com>
---
 arch/riscv/lib/uaccess.S | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/riscv/lib/uaccess.S b/arch/riscv/lib/uaccess.S
index bc22c078aba8..1fe798666aee 100644
--- a/arch/riscv/lib/uaccess.S
+++ b/arch/riscv/lib/uaccess.S
@@ -5,6 +5,7 @@
 #include <asm/csr.h>
 #include <asm/hwcap.h>
 #include <asm/alternative-macros.h>
+#include <asm/vendorid_list.h>
 
 	.macro fixup op reg addr lbl
 100:
@@ -15,6 +16,7 @@
 SYM_FUNC_START(__asm_copy_to_user)
 #ifdef CONFIG_RISCV_ISA_V
 	ALTERNATIVE("j fallback_scalar_usercopy", "nop", 0, RISCV_ISA_EXT_v, CONFIG_RISCV_ISA_V)
+	ALTERNATIVE("nop", "j fallback_scalar_usercopy", THEAD_VENDOR_ID, RISCV_ISA_VENDOR_EXT_XTHEADVECTOR, CONFIG_RISCV_ISA_XTHEADVECTOR)
 	REG_L	t0, riscv_v_usercopy_threshold
 	bltu	a2, t0, fallback_scalar_usercopy
 	tail enter_vector_usercopy

-- 
2.44.0




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