From 1f3d8699be82583c713e2a1099c597a740ebaf4d Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Thu, 8 Sep 2016 13:55:37 +0100 Subject: [PATCH] arm64/kvm: use {read,write}_sysreg() A while back we added {read,write}_sysreg accessors to handle accesses to system registers, without the usual boilerplate asm volatile, temporary variable, etc. This patch makes use of these in the arm64 KVM code to make the code shorter and clearer. At the same time, a comment style violation next to a system register access is fixed up in reset_pmcr, and comments describing whether operations are reads or writes are removed as this is now painfully obvious. Cc: Catalin Marinas Cc: Marc Zyngier Cc: Will Deacon Acked-by: Christoffer Dall Signed-off-by: Mark Rutland Signed-off-by: Will Deacon --- arch/arm64/include/asm/virt.h | 6 ++---- arch/arm64/kvm/sys_regs.c | 31 ++++++++++------------------ arch/arm64/kvm/sys_regs_generic_v8.c | 6 ++---- 3 files changed, 15 insertions(+), 28 deletions(-) diff --git a/arch/arm64/include/asm/virt.h b/arch/arm64/include/asm/virt.h index db5739413677..fea10736b11f 100644 --- a/arch/arm64/include/asm/virt.h +++ b/arch/arm64/include/asm/virt.h @@ -46,6 +46,7 @@ #include #include +#include /* * __boot_cpu_mode records what mode CPUs were booted in. @@ -76,10 +77,7 @@ static inline bool is_hyp_mode_mismatched(void) static inline bool is_kernel_in_hyp_mode(void) { - u64 el; - - asm("mrs %0, CurrentEL" : "=r" (el)); - return el == CurrentEL_EL2; + return read_sysreg(CurrentEL) == CurrentEL_EL2; } #ifdef CONFIG_ARM64_VHE diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index b0b225ceca18..295a3e536a75 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -36,6 +36,7 @@ #include #include #include +#include #include @@ -67,11 +68,9 @@ static u32 get_ccsidr(u32 csselr) /* Make sure noone else changes CSSELR during this! */ local_irq_disable(); - /* Put value into CSSELR */ - asm volatile("msr csselr_el1, %x0" : : "r" (csselr)); + write_sysreg(csselr, csselr_el1); isb(); - /* Read result out of CCSIDR */ - asm volatile("mrs %0, ccsidr_el1" : "=r" (ccsidr)); + ccsidr = read_sysreg(ccsidr_el1); local_irq_enable(); return ccsidr; @@ -174,9 +173,7 @@ static bool trap_dbgauthstatus_el1(struct kvm_vcpu *vcpu, if (p->is_write) { return ignore_write(vcpu, p); } else { - u32 val; - asm volatile("mrs %0, dbgauthstatus_el1" : "=r" (val)); - p->regval = val; + p->regval = read_sysreg(dbgauthstatus_el1); return true; } } @@ -429,10 +426,7 @@ static void reset_wcr(struct kvm_vcpu *vcpu, static void reset_amair_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { - u64 amair; - - asm volatile("mrs %0, amair_el1\n" : "=r" (amair)); - vcpu_sys_reg(vcpu, AMAIR_EL1) = amair; + vcpu_sys_reg(vcpu, AMAIR_EL1) = read_sysreg(amair_el1); } static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) @@ -456,8 +450,9 @@ static void reset_pmcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { u64 pmcr, val; - asm volatile("mrs %0, pmcr_el0\n" : "=r" (pmcr)); - /* Writable bits of PMCR_EL0 (ARMV8_PMU_PMCR_MASK) is reset to UNKNOWN + pmcr = read_sysreg(pmcr_el0); + /* + * Writable bits of PMCR_EL0 (ARMV8_PMU_PMCR_MASK) are reset to UNKNOWN * except PMCR.E resetting to zero. */ val = ((pmcr & ~ARMV8_PMU_PMCR_MASK) @@ -557,9 +552,9 @@ static bool access_pmceid(struct kvm_vcpu *vcpu, struct sys_reg_params *p, return false; if (!(p->Op2 & 1)) - asm volatile("mrs %0, pmceid0_el0\n" : "=r" (pmceid)); + pmceid = read_sysreg(pmceid0_el0); else - asm volatile("mrs %0, pmceid1_el0\n" : "=r" (pmceid)); + pmceid = read_sysreg(pmceid1_el0); p->regval = pmceid; @@ -1841,11 +1836,7 @@ static const struct sys_reg_desc *index_to_sys_reg_desc(struct kvm_vcpu *vcpu, static void get_##reg(struct kvm_vcpu *v, \ const struct sys_reg_desc *r) \ { \ - u64 val; \ - \ - asm volatile("mrs %0, " __stringify(reg) "\n" \ - : "=r" (val)); \ - ((struct sys_reg_desc *)r)->val = val; \ + ((struct sys_reg_desc *)r)->val = read_sysreg(reg); \ } FUNCTION_INVARIANT(midr_el1) diff --git a/arch/arm64/kvm/sys_regs_generic_v8.c b/arch/arm64/kvm/sys_regs_generic_v8.c index ed90578fa120..46af7186bca6 100644 --- a/arch/arm64/kvm/sys_regs_generic_v8.c +++ b/arch/arm64/kvm/sys_regs_generic_v8.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include "sys_regs.h" @@ -43,10 +44,7 @@ static bool access_actlr(struct kvm_vcpu *vcpu, static void reset_actlr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { - u64 actlr; - - asm volatile("mrs %0, actlr_el1\n" : "=r" (actlr)); - vcpu_sys_reg(vcpu, ACTLR_EL1) = actlr; + vcpu_sys_reg(vcpu, ACTLR_EL1) = read_sysreg(actlr_el1); } /*