[PATCH 04/21] arm64: bpf: Add support for generating reads of TPIDRRO_EL0

[Will Deacon]

In preparation for storing 'current' in TPIDRRO_EL0, add support for the
instruction encoding of "MRS Rt, TPIDRRO_EL0" to the BPF JIT.

Cc: Mark Rutland <mark.rutland at arm.com>
Signed-off-by: Will Deacon <will at kernel.org>
---
 arch/arm64/include/asm/insn.h | 1 +
 arch/arm64/net/bpf_jit.h      | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h
index 1ce75a442638..0e739740513d 100644
--- a/arch/arm64/include/asm/insn.h
+++ b/arch/arm64/include/asm/insn.h
@@ -136,6 +136,7 @@ enum aarch64_insn_special_register {
 };
 
 enum aarch64_insn_system_register {
+	AARCH64_INSN_SYSREG_TPIDRRO_EL0	= 0x5e83,
 	AARCH64_INSN_SYSREG_TPIDR_EL1	= 0x4684,
 	AARCH64_INSN_SYSREG_TPIDR_EL2	= 0x6682,
 	AARCH64_INSN_SYSREG_SP_EL0	= 0x4208,
diff --git a/arch/arm64/net/bpf_jit.h b/arch/arm64/net/bpf_jit.h
index b2fe6e6dcf44..df469a005373 100644
--- a/arch/arm64/net/bpf_jit.h
+++ b/arch/arm64/net/bpf_jit.h
@@ -331,6 +331,8 @@
 	aarch64_insn_gen_adr(0, offset, Rd, AARCH64_INSN_ADR_TYPE_ADR)
 
 /* MRS */
+#define A64_MRS_TPIDRRO_EL0(Rt) \
+	aarch64_insn_gen_mrs(Rt, AARCH64_INSN_SYSREG_TPIDRRO_EL0)
 #define A64_MRS_TPIDR_EL1(Rt) \
 	aarch64_insn_gen_mrs(Rt, AARCH64_INSN_SYSREG_TPIDR_EL1)
 #define A64_MRS_TPIDR_EL2(Rt) \
-- 
2.55.0.979.g7e5102b832-goog