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 charlie@rivosinc.com --- 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 92eec729888d..6e3c85351f82 100644 --- a/arch/riscv/include/asm/vendor_extensions/thead.h +++ b/arch/riscv/include/asm/vendor_extensions/thead.h @@ -16,4 +16,30 @@
extern const 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
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