Add an encoder for the EXTR instruction, which also implements the ROR
variant (where Rn == Rm).

Reviewed-by: Christoffer Dall <christoffer.d...@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
---
 arch/arm64/include/asm/insn.h |  6 ++++++
 arch/arm64/kernel/insn.c      | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)

diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h
index 815b35bc53ed..f62c56b1793f 100644
--- a/arch/arm64/include/asm/insn.h
+++ b/arch/arm64/include/asm/insn.h
@@ -319,6 +319,7 @@ __AARCH64_INSN_FUNCS(and_imm,       0x7F800000, 0x12000000)
 __AARCH64_INSN_FUNCS(orr_imm,  0x7F800000, 0x32000000)
 __AARCH64_INSN_FUNCS(eor_imm,  0x7F800000, 0x52000000)
 __AARCH64_INSN_FUNCS(ands_imm, 0x7F800000, 0x72000000)
+__AARCH64_INSN_FUNCS(extr,     0x7FA00000, 0x13800000)
 __AARCH64_INSN_FUNCS(b,                0xFC000000, 0x14000000)
 __AARCH64_INSN_FUNCS(bl,       0xFC000000, 0x94000000)
 __AARCH64_INSN_FUNCS(cbz,      0x7F000000, 0x34000000)
@@ -433,6 +434,11 @@ u32 aarch64_insn_gen_logical_immediate(enum 
aarch64_insn_logic_type type,
                                       enum aarch64_insn_register Rn,
                                       enum aarch64_insn_register Rd,
                                       u64 imm);
+u32 aarch64_insn_gen_extr(enum aarch64_insn_variant variant,
+                         enum aarch64_insn_register Rm,
+                         enum aarch64_insn_register Rn,
+                         enum aarch64_insn_register Rd,
+                         u8 lsb);
 u32 aarch64_insn_gen_prefetch(enum aarch64_insn_register base,
                              enum aarch64_insn_prfm_type type,
                              enum aarch64_insn_prfm_target target,
diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c
index 72cb1721c63f..59669d7d4383 100644
--- a/arch/arm64/kernel/insn.c
+++ b/arch/arm64/kernel/insn.c
@@ -1621,3 +1621,35 @@ u32 aarch64_insn_gen_logical_immediate(enum 
aarch64_insn_logic_type type,
        insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, Rn);
        return aarch64_encode_immediate(imm, variant, insn);
 }
+
+u32 aarch64_insn_gen_extr(enum aarch64_insn_variant variant,
+                         enum aarch64_insn_register Rm,
+                         enum aarch64_insn_register Rn,
+                         enum aarch64_insn_register Rd,
+                         u8 lsb)
+{
+       u32 insn;
+
+       insn = aarch64_insn_get_extr_value();
+
+       switch (variant) {
+       case AARCH64_INSN_VARIANT_32BIT:
+               if (lsb > 31)
+                       return AARCH64_BREAK_FAULT;
+               break;
+       case AARCH64_INSN_VARIANT_64BIT:
+               if (lsb > 63)
+                       return AARCH64_BREAK_FAULT;
+               insn |= AARCH64_INSN_SF_BIT;
+               insn = aarch64_insn_encode_immediate(AARCH64_INSN_IMM_N, insn, 
1);
+               break;
+       default:
+               pr_err("%s: unknown variant encoding %d\n", __func__, variant);
+               return AARCH64_BREAK_FAULT;
+       }
+
+       insn = aarch64_insn_encode_immediate(AARCH64_INSN_IMM_S, insn, lsb);
+       insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RD, insn, Rd);
+       insn = aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RN, insn, Rn);
+       return aarch64_insn_encode_register(AARCH64_INSN_REGTYPE_RM, insn, Rm);
+}
-- 
2.14.2

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