[PATCH 08/13] riscv: Add xtheadvector instruction definitions
From: Charlie Jenkins <hidden>
Date: 2024-06-10 04:45:52
Also in:
linux-doc, linux-kselftest, linux-riscv, linux-sunxi, lkml
Subsystem:
risc-v architecture, the rest · Maintainers:
Paul Walmsley, Palmer Dabbelt, Albert Ou, Linus Torvalds
xtheadvector uses different encodings than standard vector for vsetvli and vector loads/stores. Write the instruction formats to be used in assembly code. Co-developed-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Charlie Jenkins <redacted> --- arch/riscv/include/asm/vendor_extensions/thead.h | 26 ++++++++++++++++++++++++ 1 file changed, 26 insertions(+)
diff --git a/arch/riscv/include/asm/vendor_extensions/thead.h b/arch/riscv/include/asm/vendor_extensions/thead.h
index 48421d1553ad..27a253a20ab8 100644
--- a/arch/riscv/include/asm/vendor_extensions/thead.h
+++ b/arch/riscv/include/asm/vendor_extensions/thead.h@@ -13,4 +13,30 @@ extern struct riscv_isa_vendor_ext_data_list riscv_isa_vendor_ext_list_thead; +/* Extension specific helpers */ + +/* + * Vector 0.7.1 as used for example on T-Head Xuantie cores, uses an older + * encoding for vsetvli (ta, ma vs. d1), so provide an instruction for + * vsetvli t4, x0, e8, m8, d1 + */ +#define THEAD_VSETVLI_T4X0E8M8D1 ".long 0x00307ed7\n\t" +#define THEAD_VSETVLI_X0X0E8M8D1 ".long 0x00307057\n\t" + +/* + * While in theory, the vector-0.7.1 vsb.v and vlb.v result in the same + * encoding as the standard vse8.v and vle8.v, compilers seem to optimize + * the call resulting in a different encoding and then using a value for + * the "mop" field that is not part of vector-0.7.1 + * So encode specific variants for vstate_save and _restore. + */ +#define THEAD_VSB_V_V0T0 ".long 0x02028027\n\t" +#define THEAD_VSB_V_V8T0 ".long 0x02028427\n\t" +#define THEAD_VSB_V_V16T0 ".long 0x02028827\n\t" +#define THEAD_VSB_V_V24T0 ".long 0x02028c27\n\t" +#define THEAD_VLB_V_V0T0 ".long 0x012028007\n\t" +#define THEAD_VLB_V_V8T0 ".long 0x012028407\n\t" +#define THEAD_VLB_V_V16T0 ".long 0x012028807\n\t" +#define THEAD_VLB_V_V24T0 ".long 0x012028c07\n\t" + #endif
--
2.44.0