From 9ded63aaf83eba76e1a54ac02581c2badc497f1a Mon Sep 17 00:00:00 2001 From: "Suzuki K. Poulose" <suzuki.poulose@arm.com> Date: Wed, 22 Jul 2015 11:38:14 +0100 Subject: [PATCH] arm64: Generalise msr_s/mrs_s operations The system register encoding generated by sys_reg() works only for MRS/MSR(Register) operations, as we hardcode Bit20 to 1 in mrs_s/msr_s mask. This makes it unusable for generating instructions accessing registers with Op0 < 2(e.g, PSTATE.x with Op0=0). As per ARMv8 ARM, (Ref: ARMv8 ARM, Section: "System instruction class encoding overview", C5.2, version:ARM DDI 0487A.f), the instruction encoding reserves bits [20-19] for Op0. This patch generalises the sys_reg, mrs_s and msr_s macros, so that we could use them to access any of the supported system register. Cc: James Morse <james.morse@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> --- arch/arm64/include/asm/sysreg.h | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 56391fbae1e11..5295bcbcb3746 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -23,8 +23,18 @@ #define SCTLR_EL1_CP15BEN (0x1 << 5) #define SCTLR_EL1_SED (0x1 << 8) +/* + * ARMv8 ARM reserves the following encoding for system registers: + * (Ref: ARMv8 ARM, Section: "System instruction class encoding overview", + * C5.2, version:ARM DDI 0487A.f) + * [20-19] : Op0 + * [18-16] : Op1 + * [15-12] : CRn + * [11-8] : CRm + * [7-5] : Op2 + */ #define sys_reg(op0, op1, crn, crm, op2) \ - ((((op0)-2)<<19)|((op1)<<16)|((crn)<<12)|((crm)<<8)|((op2)<<5)) + ((((op0)&3)<<19)|((op1)<<16)|((crn)<<12)|((crm)<<8)|((op2)<<5)) #ifdef __ASSEMBLY__ @@ -34,11 +44,11 @@ .equ __reg_num_xzr, 31 .macro mrs_s, rt, sreg - .inst 0xd5300000|(\sreg)|(__reg_num_\rt) + .inst 0xd5200000|(\sreg)|(__reg_num_\rt) .endm .macro msr_s, sreg, rt - .inst 0xd5100000|(\sreg)|(__reg_num_\rt) + .inst 0xd5000000|(\sreg)|(__reg_num_\rt) .endm #else @@ -50,11 +60,11 @@ asm( " .equ __reg_num_xzr, 31\n" "\n" " .macro mrs_s, rt, sreg\n" -" .inst 0xd5300000|(\\sreg)|(__reg_num_\\rt)\n" +" .inst 0xd5200000|(\\sreg)|(__reg_num_\\rt)\n" " .endm\n" "\n" " .macro msr_s, sreg, rt\n" -" .inst 0xd5100000|(\\sreg)|(__reg_num_\\rt)\n" +" .inst 0xd5000000|(\\sreg)|(__reg_num_\\rt)\n" " .endm\n" ); -- GitLab